summaryrefslogtreecommitdiff
path: root/src/station_cmd.cpp
blob: 5fd865a0db874731388d3b286df1c45769202df3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
/* $Id$ */

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file station_cmd.cpp Handling of station tiles. */

#include "stdafx.h"
#include "aircraft.h"
#include "bridge_map.h"
#include "cmd_helper.h"
#include "viewport_func.h"
#include "command_func.h"
#include "town.h"
#include "news_func.h"
#include "train.h"
#include "ship.h"
#include "roadveh.h"
#include "industry.h"
#include "newgrf_cargo.h"
#include "newgrf_debug.h"
#include "newgrf_station.h"
#include "newgrf_canal.h" /* For the buoy */
#include "pathfinder/yapf/yapf_cache.h"
#include "road_internal.h" /* For drawing catenary/checking road removal */
#include "autoslope.h"
#include "water.h"
#include "strings_func.h"
#include "clear_func.h"
#include "date_func.h"
#include "vehicle_func.h"
#include "string_func.h"
#include "animated_tile_func.h"
#include "elrail_func.h"
#include "station_base.h"
#include "roadstop_base.h"
#include "newgrf_railtype.h"
#include "waypoint_base.h"
#include "waypoint_func.h"
#include "pbs.h"
#include "debug.h"
#include "core/random_func.hpp"
#include "company_base.h"
#include "table/airporttile_ids.h"
#include "newgrf_airporttiles.h"
#include "order_backup.h"
#include "newgrf_house.h"
#include "company_gui.h"
#include "linkgraph/linkgraph_base.h"
#include "linkgraph/refresh.h"
#include "widgets/station_widget.h"

#include "table/strings.h"

#include "safeguards.h"

/**
 * Static instance of FlowStat::SharesMap.
 * Note: This instance is created on task start.
 *       Lazy creation on first usage results in a data race between the CDist threads.
 */
/* static */ const FlowStat::SharesMap FlowStat::empty_sharesmap;

/**
 * Check whether the given tile is a hangar.
 * @param t the tile to of whether it is a hangar.
 * @pre IsTileType(t, MP_STATION)
 * @return true if and only if the tile is a hangar.
 */
bool IsHangar(TileIndex t)
{
	assert(IsTileType(t, MP_STATION));

	/* If the tile isn't an airport there's no chance it's a hangar. */
	if (!IsAirport(t)) return false;

	const Station *st = Station::GetByTile(t);
	const AirportSpec *as = st->airport.GetSpec();

	for (uint i = 0; i < as->nof_depots; i++) {
		if (st->airport.GetHangarTile(i) == t) return true;
	}

	return false;
}

/**
 * Look for a station around the given tile area.
 * @param ta the area to search over
 * @param closest_station the closest station found so far
 * @param st to 'return' the found station
 * @return Succeeded command (if zero or one station found) or failed command (for two or more stations found).
 */
template <class T>
CommandCost GetStationAround(TileArea ta, StationID closest_station, T **st)
{
	ta.tile -= TileDiffXY(1, 1);
	ta.w    += 2;
	ta.h    += 2;

	/* check around to see if there's any stations there */
	TILE_AREA_LOOP(tile_cur, ta) {
		if (IsTileType(tile_cur, MP_STATION)) {
			StationID t = GetStationIndex(tile_cur);
			if (!T::IsValidID(t)) continue;

			if (closest_station == INVALID_STATION) {
				closest_station = t;
			} else if (closest_station != t) {
				return_cmd_error(STR_ERROR_ADJOINS_MORE_THAN_ONE_EXISTING);
			}
		}
	}
	*st = (closest_station == INVALID_STATION) ? NULL : T::Get(closest_station);
	return CommandCost();
}

/**
 * Function to check whether the given tile matches some criterion.
 * @param tile the tile to check
 * @return true if it matches, false otherwise
 */
typedef bool (*CMSAMatcher)(TileIndex tile);

/**
 * Counts the numbers of tiles matching a specific type in the area around
 * @param tile the center tile of the 'count area'
 * @param cmp the comparator/matcher (@see CMSAMatcher)
 * @return the number of matching tiles around
 */
static int CountMapSquareAround(TileIndex tile, CMSAMatcher cmp)
{
	int num = 0;

	for (int dx = -3; dx <= 3; dx++) {
		for (int dy = -3; dy <= 3; dy++) {
			TileIndex t = TileAddWrap(tile, dx, dy);
			if (t != INVALID_TILE && cmp(t)) num++;
		}
	}

	return num;
}

/**
 * Check whether the tile is a mine.
 * @param tile the tile to investigate.
 * @return true if and only if the tile is a mine
 */
static bool CMSAMine(TileIndex tile)
{
	/* No industry */
	if (!IsTileType(tile, MP_INDUSTRY)) return false;

	const Industry *ind = Industry::GetByTile(tile);

	/* No extractive industry */
	if ((GetIndustrySpec(ind->type)->life_type & INDUSTRYLIFE_EXTRACTIVE) == 0) return false;

	for (uint i = 0; i < lengthof(ind->produced_cargo); i++) {
		/* The industry extracts something non-liquid, i.e. no oil or plastic, so it is a mine.
		 * Also the production of passengers and mail is ignored. */
		if (ind->produced_cargo[i] != CT_INVALID &&
				(CargoSpec::Get(ind->produced_cargo[i])->classes & (CC_LIQUID | CC_PASSENGERS | CC_MAIL)) == 0) {
			return true;
		}
	}

	return false;
}

/**
 * Check whether the tile is water.
 * @param tile the tile to investigate.
 * @return true if and only if the tile is a water tile
 */
static bool CMSAWater(TileIndex tile)
{
	return IsTileType(tile, MP_WATER) && IsWater(tile);
}

/**
 * Check whether the tile is a tree.
 * @param tile the tile to investigate.
 * @return true if and only if the tile is a tree tile
 */
static bool CMSATree(TileIndex tile)
{
	return IsTileType(tile, MP_TREES);
}

#define M(x) ((x) - STR_SV_STNAME)

enum StationNaming {
	STATIONNAMING_RAIL,
	STATIONNAMING_ROAD,
	STATIONNAMING_AIRPORT,
	STATIONNAMING_OILRIG,
	STATIONNAMING_DOCK,
	STATIONNAMING_HELIPORT,
};

/** Information to handle station action 0 property 24 correctly */
struct StationNameInformation {
	uint32 free_names; ///< Current bitset of free names (we can remove names).
	bool *indtypes;    ///< Array of bools telling whether an industry type has been found.
};

/**
 * Find a station action 0 property 24 station name, or reduce the
 * free_names if needed.
 * @param tile the tile to search
 * @param user_data the StationNameInformation to base the search on
 * @return true if the tile contains an industry that has not given
 *              its name to one of the other stations in town.
 */
static bool FindNearIndustryName(TileIndex tile, void *user_data)
{
	/* All already found industry types */
	StationNameInformation *sni = (StationNameInformation*)user_data;
	if (!IsTileType(tile, MP_INDUSTRY)) return false;

	/* If the station name is undefined it means that it doesn't name a station */
	IndustryType indtype = GetIndustryType(tile);
	if (GetIndustrySpec(indtype)->station_name == STR_UNDEFINED) return false;

	/* In all cases if an industry that provides a name is found two of
	 * the standard names will be disabled. */
	sni->free_names &= ~(1 << M(STR_SV_STNAME_OILFIELD) | 1 << M(STR_SV_STNAME_MINES));
	return !sni->indtypes[indtype];
}

static StringID GenerateStationName(Station *st, TileIndex tile, StationNaming name_class)
{
	static const uint32 _gen_station_name_bits[] = {
		0,                                       // STATIONNAMING_RAIL
		0,                                       // STATIONNAMING_ROAD
		1U << M(STR_SV_STNAME_AIRPORT),          // STATIONNAMING_AIRPORT
		1U << M(STR_SV_STNAME_OILFIELD),         // STATIONNAMING_OILRIG
		1U << M(STR_SV_STNAME_DOCKS),            // STATIONNAMING_DOCK
		1U << M(STR_SV_STNAME_HELIPORT),         // STATIONNAMING_HELIPORT
	};

	const Town *t = st->town;
	uint32 free_names = UINT32_MAX;

	bool indtypes[NUM_INDUSTRYTYPES];
	memset(indtypes, 0, sizeof(indtypes));

	const Station *s;
	FOR_ALL_STATIONS(s) {
		if (s != st && s->town == t) {
			if (s->indtype != IT_INVALID) {
				indtypes[s->indtype] = true;
				StringID name = GetIndustrySpec(s->indtype)->station_name;
				if (name != STR_UNDEFINED) {
					/* Filter for other industrytypes with the same name */
					for (IndustryType it = 0; it < NUM_INDUSTRYTYPES; it++) {
						const IndustrySpec *indsp = GetIndustrySpec(it);
						if (indsp->enabled && indsp->station_name == name) indtypes[it] = true;
					}
				}
				continue;
			}
			uint str = M(s->string_id);
			if (str <= 0x20) {
				if (str == M(STR_SV_STNAME_FOREST)) {
					str = M(STR_SV_STNAME_WOODS);
				}
				ClrBit(free_names, str);
			}
		}
	}

	TileIndex indtile = tile;
	StationNameInformation sni = { free_names, indtypes };
	if (CircularTileSearch(&indtile, 7, FindNearIndustryName, &sni)) {
		/* An industry has been found nearby */
		IndustryType indtype = GetIndustryType(indtile);
		const IndustrySpec *indsp = GetIndustrySpec(indtype);
		/* STR_NULL means it only disables oil rig/mines */
		if (indsp->station_name != STR_NULL) {
			st->indtype = indtype;
			return STR_SV_STNAME_FALLBACK;
		}
	}

	/* Oil rigs/mines name could be marked not free by looking for a near by industry. */
	free_names = sni.free_names;

	/* check default names */
	uint32 tmp = free_names & _gen_station_name_bits[name_class];
	if (tmp != 0) return STR_SV_STNAME + FindFirstBit(tmp);

	/* check mine? */
	if (HasBit(free_names, M(STR_SV_STNAME_MINES))) {
		if (CountMapSquareAround(tile, CMSAMine) >= 2) {
			return STR_SV_STNAME_MINES;
		}
	}

	/* check close enough to town to get central as name? */
	if (DistanceMax(tile, t->xy) < 8) {
		if (HasBit(free_names, M(STR_SV_STNAME))) return STR_SV_STNAME;

		if (HasBit(free_names, M(STR_SV_STNAME_CENTRAL))) return STR_SV_STNAME_CENTRAL;
	}

	/* Check lakeside */
	if (HasBit(free_names, M(STR_SV_STNAME_LAKESIDE)) &&
			DistanceFromEdge(tile) < 20 &&
			CountMapSquareAround(tile, CMSAWater) >= 5) {
		return STR_SV_STNAME_LAKESIDE;
	}

	/* Check woods */
	if (HasBit(free_names, M(STR_SV_STNAME_WOODS)) && (
				CountMapSquareAround(tile, CMSATree) >= 8 ||
				CountMapSquareAround(tile, IsTileForestIndustry) >= 2)
			) {
		return _settings_game.game_creation.landscape == LT_TROPIC ? STR_SV_STNAME_FOREST : STR_SV_STNAME_WOODS;
	}

	/* check elevation compared to town */
	int z = GetTileZ(tile);
	int z2 = GetTileZ(t->xy);
	if (z < z2) {
		if (HasBit(free_names, M(STR_SV_STNAME_VALLEY))) return STR_SV_STNAME_VALLEY;
	} else if (z > z2) {
		if (HasBit(free_names, M(STR_SV_STNAME_HEIGHTS))) return STR_SV_STNAME_HEIGHTS;
	}

	/* check direction compared to town */
	static const int8 _direction_and_table[] = {
		~( (1 << M(STR_SV_STNAME_WEST))  | (1 << M(STR_SV_STNAME_EAST)) | (1 << M(STR_SV_STNAME_NORTH)) ),
		~( (1 << M(STR_SV_STNAME_SOUTH)) | (1 << M(STR_SV_STNAME_WEST)) | (1 << M(STR_SV_STNAME_NORTH)) ),
		~( (1 << M(STR_SV_STNAME_SOUTH)) | (1 << M(STR_SV_STNAME_EAST)) | (1 << M(STR_SV_STNAME_NORTH)) ),
		~( (1 << M(STR_SV_STNAME_SOUTH)) | (1 << M(STR_SV_STNAME_WEST)) | (1 << M(STR_SV_STNAME_EAST)) ),
	};

	free_names &= _direction_and_table[
		(TileX(tile) < TileX(t->xy)) +
		(TileY(tile) < TileY(t->xy)) * 2];

	tmp = free_names & ((1 << 1) | (1 << 2) | (1 << 3) | (1 << 4) | (1 << 6) | (1 << 7) | (1 << 12) | (1 << 26) | (1 << 27) | (1 << 28) | (1 << 29) | (1 << 30));
	return (tmp == 0) ? STR_SV_STNAME_FALLBACK : (STR_SV_STNAME + FindFirstBit(tmp));
}
#undef M

/**
 * Find the closest deleted station of the current company
 * @param tile the tile to search from.
 * @return the closest station or NULL if too far.
 */
static Station *GetClosestDeletedStation(TileIndex tile)
{
	uint threshold = 8;
	Station *best_station = NULL;
	Station *st;

	FOR_ALL_STATIONS(st) {
		if (!st->IsInUse() && st->owner == _current_company) {
			uint cur_dist = DistanceManhattan(tile, st->xy);

			if (cur_dist < threshold) {
				threshold = cur_dist;
				best_station = st;
			}
		}
	}

	return best_station;
}


void Station::GetTileArea(TileArea *ta, StationType type) const
{
	switch (type) {
		case STATION_RAIL:
			*ta = this->train_station;
			return;

		case STATION_AIRPORT:
			*ta = this->airport;
			return;

		case STATION_TRUCK:
			*ta = this->truck_station;
			return;

		case STATION_BUS:
			*ta = this->bus_station;
			return;

		case STATION_DOCK:
		case STATION_OILRIG:
			ta->tile = this->dock_tile;
			break;

		default: NOT_REACHED();
	}

	ta->w = 1;
	ta->h = 1;
}

/**
 * Update the virtual coords needed to draw the station sign.
 */
void Station::UpdateVirtCoord()
{
	Point pt = RemapCoords2(TileX(this->xy) * TILE_SIZE, TileY(this->xy) * TILE_SIZE);

	pt.y -= 32 * ZOOM_LVL_BASE;
	if ((this->facilities & FACIL_AIRPORT) && this->airport.type == AT_OILRIG) pt.y -= 16 * ZOOM_LVL_BASE;

	SetDParam(0, this->index);
	SetDParam(1, this->facilities);
	this->sign.UpdatePosition(pt.x, pt.y, STR_VIEWPORT_STATION);

	SetWindowDirty(WC_STATION_VIEW, this->index);
}

/** Update the virtual coords needed to draw the station sign for all stations. */
void UpdateAllStationVirtCoords()
{
	BaseStation *st;

	FOR_ALL_BASE_STATIONS(st) {
		st->UpdateVirtCoord();
	}
}

/**
 * Get a mask of the cargo types that the station accepts.
 * @param st Station to query
 * @return the expected mask
 */
static uint GetAcceptanceMask(const Station *st)
{
	uint mask = 0;

	for (CargoID i = 0; i < NUM_CARGO; i++) {
		if (HasBit(st->goods[i].status, GoodsEntry::GES_ACCEPTANCE)) mask |= 1 << i;
	}
	return mask;
}

/**
 * Items contains the two cargo names that are to be accepted or rejected.
 * msg is the string id of the message to display.
 */
static void ShowRejectOrAcceptNews(const Station *st, uint num_items, CargoID *cargo, StringID msg)
{
	for (uint i = 0; i < num_items; i++) {
		SetDParam(i + 1, CargoSpec::Get(cargo[i])->name);
	}

	SetDParam(0, st->index);
	AddNewsItem(msg, NT_ACCEPTANCE, NF_INCOLOUR | NF_SMALL, NR_STATION, st->index);
}

/**
 * Get the cargo types being produced around the tile (in a rectangle).
 * @param tile Northtile of area
 * @param w X extent of the area
 * @param h Y extent of the area
 * @param rad Search radius in addition to the given area
 */
CargoArray GetProductionAroundTiles(TileIndex tile, int w, int h, int rad)
{
	CargoArray produced;

	int x = TileX(tile);
	int y = TileY(tile);

	/* expand the region by rad tiles on each side
	 * while making sure that we remain inside the board. */
	int x2 = min(x + w + rad, MapSizeX());
	int x1 = max(x - rad, 0);

	int y2 = min(y + h + rad, MapSizeY());
	int y1 = max(y - rad, 0);

	assert(x1 < x2);
	assert(y1 < y2);
	assert(w > 0);
	assert(h > 0);

	TileArea ta(TileXY(x1, y1), TileXY(x2 - 1, y2 - 1));

	/* Loop over all tiles to get the produced cargo of
	 * everything except industries */
	TILE_AREA_LOOP(tile, ta) AddProducedCargo(tile, produced);

	/* Loop over the industries. They produce cargo for
	 * anything that is within 'rad' from their bounding
	 * box. As such if you have e.g. a oil well the tile
	 * area loop might not hit an industry tile while
	 * the industry would produce cargo for the station.
	 */
	const Industry *i;
	FOR_ALL_INDUSTRIES(i) {
		if (!ta.Intersects(i->location)) continue;

		for (uint j = 0; j < lengthof(i->produced_cargo); j++) {
			CargoID cargo = i->produced_cargo[j];
			if (cargo != CT_INVALID) produced[cargo]++;
		}
	}

	return produced;
}

/**
 * Get the acceptance of cargoes around the tile in 1/8.
 * @param tile Center of the search area
 * @param w X extent of area
 * @param h Y extent of area
 * @param rad Search radius in addition to given area
 * @param always_accepted bitmask of cargo accepted by houses and headquarters; can be NULL
 */
CargoArray GetAcceptanceAroundTiles(TileIndex tile, int w, int h, int rad, uint32 *always_accepted)
{
	CargoArray acceptance;
	if (always_accepted != NULL) *always_accepted = 0;

	int x = TileX(tile);
	int y = TileY(tile);

	/* expand the region by rad tiles on each side
	 * while making sure that we remain inside the board. */
	int x2 = min(x + w + rad, MapSizeX());
	int y2 = min(y + h + rad, MapSizeY());
	int x1 = max(x - rad, 0);
	int y1 = max(y - rad, 0);

	assert(x1 < x2);
	assert(y1 < y2);
	assert(w > 0);
	assert(h > 0);

	for (int yc = y1; yc != y2; yc++) {
		for (int xc = x1; xc != x2; xc++) {
			TileIndex tile = TileXY(xc, yc);
			AddAcceptedCargo(tile, acceptance, always_accepted);
		}
	}

	return acceptance;
}

/**
 * Update the acceptance for a station.
 * @param st Station to update
 * @param show_msg controls whether to display a message that acceptance was changed.
 */
void UpdateStationAcceptance(Station *st, bool show_msg)
{
	/* old accepted goods types */
	uint old_acc = GetAcceptanceMask(st);

	/* And retrieve the acceptance. */
	CargoArray acceptance;
	if (!st->rect.IsEmpty()) {
		acceptance = GetAcceptanceAroundTiles(
			TileXY(st->rect.left, st->rect.top),
			st->rect.right  - st->rect.left + 1,
			st->rect.bottom - st->rect.top  + 1,
			st->GetCatchmentRadius(),
			&st->always_accepted
		);
	}

	/* Adjust in case our station only accepts fewer kinds of goods */
	for (CargoID i = 0; i < NUM_CARGO; i++) {
		uint amt = acceptance[i];

		/* Make sure the station can accept the goods type. */
		bool is_passengers = IsCargoInClass(i, CC_PASSENGERS);
		if ((!is_passengers && !(st->facilities & ~FACIL_BUS_STOP)) ||
				(is_passengers && !(st->facilities & ~FACIL_TRUCK_STOP))) {
			amt = 0;
		}

		GoodsEntry &ge = st->goods[i];
		SB(ge.status, GoodsEntry::GES_ACCEPTANCE, 1, amt >= 8);
		if (LinkGraph::IsValidID(ge.link_graph)) {
			(*LinkGraph::Get(ge.link_graph))[ge.node].SetDemand(amt / 8);
		}
	}

	/* Only show a message in case the acceptance was actually changed. */
	uint new_acc = GetAcceptanceMask(st);
	if (old_acc == new_acc) return;

	/* show a message to report that the acceptance was changed? */
	if (show_msg && st->owner == _local_company && st->IsInUse()) {
		/* List of accept and reject strings for different number of
		 * cargo types */
		static const StringID accept_msg[] = {
			STR_NEWS_STATION_NOW_ACCEPTS_CARGO,
			STR_NEWS_STATION_NOW_ACCEPTS_CARGO_AND_CARGO,
		};
		static const StringID reject_msg[] = {
			STR_NEWS_STATION_NO_LONGER_ACCEPTS_CARGO,
			STR_NEWS_STATION_NO_LONGER_ACCEPTS_CARGO_OR_CARGO,
		};

		/* Array of accepted and rejected cargo types */
		CargoID accepts[2] = { CT_INVALID, CT_INVALID };
		CargoID rejects[2] = { CT_INVALID, CT_INVALID };
		uint num_acc = 0;
		uint num_rej = 0;

		/* Test each cargo type to see if its acceptance has changed */
		for (CargoID i = 0; i < NUM_CARGO; i++) {
			if (HasBit(new_acc, i)) {
				if (!HasBit(old_acc, i) && num_acc < lengthof(accepts)) {
					/* New cargo is accepted */
					accepts[num_acc++] = i;
				}
			} else {
				if (HasBit(old_acc, i) && num_rej < lengthof(rejects)) {
					/* Old cargo is no longer accepted */
					rejects[num_rej++] = i;
				}
			}
		}

		/* Show news message if there are any changes */
		if (num_acc > 0) ShowRejectOrAcceptNews(st, num_acc, accepts, accept_msg[num_acc - 1]);
		if (num_rej > 0) ShowRejectOrAcceptNews(st, num_rej, rejects, reject_msg[num_rej - 1]);
	}

	/* redraw the station view since acceptance changed */
	SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_ACCEPT_RATING_LIST);
}

static void UpdateStationSignCoord(BaseStation *st)
{
	const StationRect *r = &st->rect;

	if (r->IsEmpty()) return; // no tiles belong to this station

	/* clamp sign coord to be inside the station rect */
	st->xy = TileXY(ClampU(TileX(st->xy), r->left, r->right), ClampU(TileY(st->xy), r->top, r->bottom));
	st->UpdateVirtCoord();

	if (!Station::IsExpected(st)) return;
	Station *full_station = Station::From(st);
	for (CargoID c = 0; c < NUM_CARGO; ++c) {
		LinkGraphID lg = full_station->goods[c].link_graph;
		if (!LinkGraph::IsValidID(lg)) continue;
		(*LinkGraph::Get(lg))[full_station->goods[c].node].UpdateLocation(st->xy);
	}
}

/**
 * Common part of building various station parts and possibly attaching them to an existing one.
 * @param [in,out] st Station to attach to
 * @param flags Command flags
 * @param reuse Whether to try to reuse a deleted station (gray sign) if possible
 * @param area Area occupied by the new part
 * @param name_class Station naming class to use to generate the new station's name
 * @return Command error that occurred, if any
 */
static CommandCost BuildStationPart(Station **st, DoCommandFlag flags, bool reuse, TileArea area, StationNaming name_class)
{
	/* Find a deleted station close to us */
	if (*st == NULL && reuse) *st = GetClosestDeletedStation(area.tile);

	if (*st != NULL) {
		if ((*st)->owner != _current_company) {
			return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_STATION);
		}

		CommandCost ret = (*st)->rect.BeforeAddRect(area.tile, area.w, area.h, StationRect::ADD_TEST);
		if (ret.Failed()) return ret;
	} else {
		/* allocate and initialize new station */
		if (!Station::CanAllocateItem()) return_cmd_error(STR_ERROR_TOO_MANY_STATIONS_LOADING);

		if (flags & DC_EXEC) {
			*st = new Station(area.tile);

			(*st)->town = ClosestTownFromTile(area.tile, UINT_MAX);
			(*st)->string_id = GenerateStationName(*st, area.tile, name_class);

			if (Company::IsValidID(_current_company)) {
				SetBit((*st)->town->have_ratings, _current_company);
			}
		}
	}
	return CommandCost();
}

/**
 * This is called right after a station was deleted.
 * It checks if the whole station is free of substations, and if so, the station will be
 * deleted after a little while.
 * @param st Station
 */
static void DeleteStationIfEmpty(BaseStation *st)
{
	if (!st->IsInUse()) {
		st->delete_ctr = 0;
		InvalidateWindowData(WC_STATION_LIST, st->owner, 0);
	}
	/* station remains but it probably lost some parts - station sign should stay in the station boundaries */
	UpdateStationSignCoord(st);
}

CommandCost ClearTile_Station(TileIndex tile, DoCommandFlag flags);

/**
 * Checks if the given tile is buildable, flat and has a certain height.
 * @param tile TileIndex to check.
 * @param invalid_dirs Prohibited directions for slopes (set of #DiagDirection).
 * @param allowed_z Height allowed for the tile. If allowed_z is negative, it will be set to the height of this tile.
 * @param allow_steep Whether steep slopes are allowed.
 * @param check_bridge Check for the existence of a bridge.
 * @return The cost in case of success, or an error code if it failed.
 */
CommandCost CheckBuildableTile(TileIndex tile, uint invalid_dirs, int &allowed_z, bool allow_steep, bool check_bridge = true)
{
	if (check_bridge && IsBridgeAbove(tile)) {
		return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
	}

	CommandCost ret = EnsureNoVehicleOnGround(tile);
	if (ret.Failed()) return ret;

	int z;
	Slope tileh = GetTileSlope(tile, &z);

	/* Prohibit building if
	 *   1) The tile is "steep" (i.e. stretches two height levels).
	 *   2) The tile is non-flat and the build_on_slopes switch is disabled.
	 */
	if ((!allow_steep && IsSteepSlope(tileh)) ||
			((!_settings_game.construction.build_on_slopes) && tileh != SLOPE_FLAT)) {
		return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
	}

	CommandCost cost(EXPENSES_CONSTRUCTION);
	int flat_z = z + GetSlopeMaxZ(tileh);
	if (tileh != SLOPE_FLAT) {
		/* Forbid building if the tile faces a slope in a invalid direction. */
		for (DiagDirection dir = DIAGDIR_BEGIN; dir != DIAGDIR_END; dir++) {
			if (HasBit(invalid_dirs, dir) && !CanBuildDepotByTileh(dir, tileh)) {
				return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
			}
		}
		cost.AddCost(_price[PR_BUILD_FOUNDATION]);
	}

	/* The level of this tile must be equal to allowed_z. */
	if (allowed_z < 0) {
		/* First tile. */
		allowed_z = flat_z;
	} else if (allowed_z != flat_z) {
		return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
	}

	return cost;
}

/**
 * Tries to clear the given area.
 * @param tile_area Area to check.
 * @param flags Operation to perform.
 * @return The cost in case of success, or an error code if it failed.
 */
CommandCost CheckFlatLand(TileArea tile_area, DoCommandFlag flags)
{
	CommandCost cost(EXPENSES_CONSTRUCTION);
	int allowed_z = -1;

	TILE_AREA_LOOP(tile_cur, tile_area) {
		CommandCost ret = CheckBuildableTile(tile_cur, 0, allowed_z, true);
		if (ret.Failed()) return ret;
		cost.AddCost(ret);

		ret = DoCommand(tile_cur, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
		if (ret.Failed()) return ret;
		cost.AddCost(ret);
	}

	return cost;
}

/**
 * Checks if a rail station can be built at the given area.
 * @param tile_area Area to check.
 * @param flags Operation to perform.
 * @param axis Rail station axis.
 * @param station StationID to be queried and returned if available.
 * @param rt The rail type to check for (overbuilding rail stations over rail).
 * @param affected_vehicles List of trains with PBS reservations on the tiles
 * @param spec_class Station class.
 * @param spec_index Index into the station class.
 * @param plat_len Platform length.
 * @param numtracks Number of platforms.
 * @return The cost in case of success, or an error code if it failed.
 */
static CommandCost CheckFlatLandRailStation(TileArea tile_area, DoCommandFlag flags, Axis axis, StationID *station, RailType rt, SmallVector<Train *, 4> &affected_vehicles, StationClassID spec_class, byte spec_index, byte plat_len, byte numtracks)
{
	CommandCost cost(EXPENSES_CONSTRUCTION);
	int allowed_z = -1;
	uint invalid_dirs = 5 << axis;

	const StationSpec *statspec = StationClass::Get(spec_class)->GetSpec(spec_index);
	bool slope_cb = statspec != NULL && HasBit(statspec->callback_mask, CBM_STATION_SLOPE_CHECK);

	TILE_AREA_LOOP(tile_cur, tile_area) {
		CommandCost ret = CheckBuildableTile(tile_cur, invalid_dirs, allowed_z, false);
		if (ret.Failed()) return ret;
		cost.AddCost(ret);

		if (slope_cb) {
			/* Do slope check if requested. */
			ret = PerformStationTileSlopeCheck(tile_area.tile, tile_cur, statspec, axis, plat_len, numtracks);
			if (ret.Failed()) return ret;
		}

		/* if station is set, then we have special handling to allow building on top of already existing stations.
		 * so station points to INVALID_STATION if we can build on any station.
		 * Or it points to a station if we're only allowed to build on exactly that station. */
		if (station != NULL && IsTileType(tile_cur, MP_STATION)) {
			if (!IsRailStation(tile_cur)) {
				return ClearTile_Station(tile_cur, DC_AUTO); // get error message
			} else {
				StationID st = GetStationIndex(tile_cur);
				if (*station == INVALID_STATION) {
					*station = st;
				} else if (*station != st) {
					return_cmd_error(STR_ERROR_ADJOINS_MORE_THAN_ONE_EXISTING);
				}
			}
		} else {
			/* Rail type is only valid when building a railway station; if station to
			 * build isn't a rail station it's INVALID_RAILTYPE. */
			if (rt != INVALID_RAILTYPE &&
					IsPlainRailTile(tile_cur) && !HasSignals(tile_cur) &&
					HasPowerOnRail(GetRailType(tile_cur), rt)) {
				/* Allow overbuilding if the tile:
				 *  - has rail, but no signals
				 *  - it has exactly one track
				 *  - the track is in line with the station
				 *  - the current rail type has power on the to-be-built type (e.g. convert normal rail to el rail)
				 */
				TrackBits tracks = GetTrackBits(tile_cur);
				Track track = RemoveFirstTrack(&tracks);
				Track expected_track = HasBit(invalid_dirs, DIAGDIR_NE) ? TRACK_X : TRACK_Y;

				if (tracks == TRACK_BIT_NONE && track == expected_track) {
					/* Check for trains having a reservation for this tile. */
					if (HasBit(GetRailReservationTrackBits(tile_cur), track)) {
						Train *v = GetTrainForReservation(tile_cur, track);
						if (v != NULL) {
							*affected_vehicles.Append() = v;
						}
					}
					CommandCost ret = DoCommand(tile_cur, 0, track, flags, CMD_REMOVE_SINGLE_RAIL);
					if (ret.Failed()) return ret;
					cost.AddCost(ret);
					/* With flags & ~DC_EXEC CmdLandscapeClear would fail since the rail still exists */
					continue;
				}
			}
			ret = DoCommand(tile_cur, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
			if (ret.Failed()) return ret;
			cost.AddCost(ret);
		}
	}

	return cost;
}

/**
 * Checks if a road stop can be built at the given tile.
 * @param tile_area Area to check.
 * @param flags Operation to perform.
 * @param invalid_dirs Prohibited directions (set of DiagDirections).
 * @param is_drive_through True if trying to build a drive-through station.
 * @param is_truck_stop True when building a truck stop, false otherwise.
 * @param axis Axis of a drive-through road stop.
 * @param station StationID to be queried and returned if available.
 * @param rts Road types to build.
 * @return The cost in case of success, or an error code if it failed.
 */
static CommandCost CheckFlatLandRoadStop(TileArea tile_area, DoCommandFlag flags, uint invalid_dirs, bool is_drive_through, bool is_truck_stop, Axis axis, StationID *station, RoadTypes rts)
{
	CommandCost cost(EXPENSES_CONSTRUCTION);
	int allowed_z = -1;

	TILE_AREA_LOOP(cur_tile, tile_area) {
		CommandCost ret = CheckBuildableTile(cur_tile, invalid_dirs, allowed_z, !is_drive_through);
		if (ret.Failed()) return ret;
		cost.AddCost(ret);

		/* If station is set, then we have special handling to allow building on top of already existing stations.
		 * Station points to INVALID_STATION if we can build on any station.
		 * Or it points to a station if we're only allowed to build on exactly that station. */
		if (station != NULL && IsTileType(cur_tile, MP_STATION)) {
			if (!IsRoadStop(cur_tile)) {
				return ClearTile_Station(cur_tile, DC_AUTO); // Get error message.
			} else {
				if (is_truck_stop != IsTruckStop(cur_tile) ||
						is_drive_through != IsDriveThroughStopTile(cur_tile)) {
					return ClearTile_Station(cur_tile, DC_AUTO); // Get error message.
				}
				/* Drive-through station in the wrong direction. */
				if (is_drive_through && IsDriveThroughStopTile(cur_tile) && DiagDirToAxis(GetRoadStopDir(cur_tile)) != axis){
					return_cmd_error(STR_ERROR_DRIVE_THROUGH_DIRECTION);
				}
				StationID st = GetStationIndex(cur_tile);
				if (*station == INVALID_STATION) {
					*station = st;
				} else if (*station != st) {
					return_cmd_error(STR_ERROR_ADJOINS_MORE_THAN_ONE_EXISTING);
				}
			}
		} else {
			bool build_over_road = is_drive_through && IsNormalRoadTile(cur_tile);
			/* Road bits in the wrong direction. */
			RoadBits rb = IsNormalRoadTile(cur_tile) ? GetAllRoadBits(cur_tile) : ROAD_NONE;
			if (build_over_road && (rb & (axis == AXIS_X ? ROAD_Y : ROAD_X)) != 0) {
				/* Someone was pedantic and *NEEDED* three fracking different error messages. */
				switch (CountBits(rb)) {
					case 1:
						return_cmd_error(STR_ERROR_DRIVE_THROUGH_DIRECTION);

					case 2:
						if (rb == ROAD_X || rb == ROAD_Y) return_cmd_error(STR_ERROR_DRIVE_THROUGH_DIRECTION);
						return_cmd_error(STR_ERROR_DRIVE_THROUGH_CORNER);

					default: // 3 or 4
						return_cmd_error(STR_ERROR_DRIVE_THROUGH_JUNCTION);
				}
			}

			RoadTypes cur_rts = IsNormalRoadTile(cur_tile) ? GetRoadTypes(cur_tile) : ROADTYPES_NONE;
			uint num_roadbits = 0;
			if (build_over_road) {
				/* There is a road, check if we can build road+tram stop over it. */
				if (HasBit(cur_rts, ROADTYPE_ROAD)) {
					Owner road_owner = GetRoadOwner(cur_tile, ROADTYPE_ROAD);
					if (road_owner == OWNER_TOWN) {
						if (!_settings_game.construction.road_stop_on_town_road) return_cmd_error(STR_ERROR_DRIVE_THROUGH_ON_TOWN_ROAD);
					} else if (!_settings_game.construction.road_stop_on_competitor_road && road_owner != OWNER_NONE) {
						CommandCost ret = CheckOwnership(road_owner);
						if (ret.Failed()) return ret;
					}
					num_roadbits += CountBits(GetRoadBits(cur_tile, ROADTYPE_ROAD));
				}

				/* There is a tram, check if we can build road+tram stop over it. */
				if (HasBit(cur_rts, ROADTYPE_TRAM)) {
					Owner tram_owner = GetRoadOwner(cur_tile, ROADTYPE_TRAM);
					if (Company::IsValidID(tram_owner) &&
							(!_settings_game.construction.road_stop_on_competitor_road ||
							/* Disallow breaking end-of-line of someone else
							 * so trams can still reverse on this tile. */
							HasExactlyOneBit(GetRoadBits(cur_tile, ROADTYPE_TRAM)))) {
						CommandCost ret = CheckOwnership(tram_owner);
						if (ret.Failed()) return ret;
					}
					num_roadbits += CountBits(GetRoadBits(cur_tile, ROADTYPE_TRAM));
				}

				/* Take into account existing roadbits. */
				rts |= cur_rts;
			} else {
				ret = DoCommand(cur_tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
				if (ret.Failed()) return ret;
				cost.AddCost(ret);
			}

			uint roadbits_to_build = CountBits(rts) * 2 - num_roadbits;
			cost.AddCost(_price[PR_BUILD_ROAD] * roadbits_to_build);
		}
	}

	return cost;
}

/**
 * Check whether we can expand the rail part of the given station.
 * @param st the station to expand
 * @param new_ta the current (and if all is fine new) tile area of the rail part of the station
 * @param axis the axis of the newly build rail
 * @return Succeeded or failed command.
 */
CommandCost CanExpandRailStation(const BaseStation *st, TileArea &new_ta, Axis axis)
{
	TileArea cur_ta = st->train_station;

	/* determine new size of train station region.. */
	int x = min(TileX(cur_ta.tile), TileX(new_ta.tile));
	int y = min(TileY(cur_ta.tile), TileY(new_ta.tile));
	new_ta.w = max(TileX(cur_ta.tile) + cur_ta.w, TileX(new_ta.tile) + new_ta.w) - x;
	new_ta.h = max(TileY(cur_ta.tile) + cur_ta.h, TileY(new_ta.tile) + new_ta.h) - y;
	new_ta.tile = TileXY(x, y);

	/* make sure the final size is not too big. */
	if (new_ta.w > _settings_game.station.station_spread || new_ta.h > _settings_game.station.station_spread) {
		return_cmd_error(STR_ERROR_STATION_TOO_SPREAD_OUT);
	}

	return CommandCost();
}

static inline byte *CreateSingle(byte *layout, int n)
{
	int i = n;
	do *layout++ = 0; while (--i);
	layout[((n - 1) >> 1) - n] = 2;
	return layout;
}

static inline byte *CreateMulti(byte *layout, int n, byte b)
{
	int i = n;
	do *layout++ = b; while (--i);
	if (n > 4) {
		layout[0 - n] = 0;
		layout[n - 1 - n] = 0;
	}
	return layout;
}

/**
 * Create the station layout for the given number of tracks and platform length.
 * @param layout    The layout to write to.
 * @param numtracks The number of tracks to write.
 * @param plat_len  The length of the platforms.
 * @param statspec  The specification of the station to (possibly) get the layout from.
 */
void GetStationLayout(byte *layout, int numtracks, int plat_len, const StationSpec *statspec)
{
	if (statspec != NULL && statspec->lengths >= plat_len &&
			statspec->platforms[plat_len - 1] >= numtracks &&
			statspec->layouts[plat_len - 1][numtracks - 1]) {
		/* Custom layout defined, follow it. */
		memcpy(layout, statspec->layouts[plat_len - 1][numtracks - 1],
			plat_len * numtracks);
		return;
	}

	if (plat_len == 1) {
		CreateSingle(layout, numtracks);
	} else {
		if (numtracks & 1) layout = CreateSingle(layout, plat_len);
		numtracks >>= 1;

		while (--numtracks >= 0) {
			layout = CreateMulti(layout, plat_len, 4);
			layout = CreateMulti(layout, plat_len, 6);
		}
	}
}

/**
 * Find a nearby station that joins this station.
 * @tparam T the class to find a station for
 * @tparam error_message the error message when building a station on top of others
 * @param existing_station an existing station we build over
 * @param station_to_join the station to join to
 * @param adjacent whether adjacent stations are allowed
 * @param ta the area of the newly build station
 * @param st 'return' pointer for the found station
 * @return command cost with the error or 'okay'
 */
template <class T, StringID error_message>
CommandCost FindJoiningBaseStation(StationID existing_station, StationID station_to_join, bool adjacent, TileArea ta, T **st)
{
	assert(*st == NULL);
	bool check_surrounding = true;

	if (_settings_game.station.adjacent_stations) {
		if (existing_station != INVALID_STATION) {
			if (adjacent && existing_station != station_to_join) {
				/* You can't build an adjacent station over the top of one that
				 * already exists. */
				return_cmd_error(error_message);
			} else {
				/* Extend the current station, and don't check whether it will
				 * be near any other stations. */
				*st = T::GetIfValid(existing_station);
				check_surrounding = (*st == NULL);
			}
		} else {
			/* There's no station here. Don't check the tiles surrounding this
			 * one if the company wanted to build an adjacent station. */
			if (adjacent) check_surrounding = false;
		}
	}

	if (check_surrounding) {
		/* Make sure there are no similar stations around us. */
		CommandCost ret = GetStationAround(ta, existing_station, st);
		if (ret.Failed()) return ret;
	}

	/* Distant join */
	if (*st == NULL && station_to_join != INVALID_STATION) *st = T::GetIfValid(station_to_join);

	return CommandCost();
}

/**
 * Find a nearby station that joins this station.
 * @param existing_station an existing station we build over
 * @param station_to_join the station to join to
 * @param adjacent whether adjacent stations are allowed
 * @param ta the area of the newly build station
 * @param st 'return' pointer for the found station
 * @return command cost with the error or 'okay'
 */
static CommandCost FindJoiningStation(StationID existing_station, StationID station_to_join, bool adjacent, TileArea ta, Station **st)
{
	return FindJoiningBaseStation<Station, STR_ERROR_MUST_REMOVE_RAILWAY_STATION_FIRST>(existing_station, station_to_join, adjacent, ta, st);
}

/**
 * Find a nearby waypoint that joins this waypoint.
 * @param existing_waypoint an existing waypoint we build over
 * @param waypoint_to_join the waypoint to join to
 * @param adjacent whether adjacent waypoints are allowed
 * @param ta the area of the newly build waypoint
 * @param wp 'return' pointer for the found waypoint
 * @return command cost with the error or 'okay'
 */
CommandCost FindJoiningWaypoint(StationID existing_waypoint, StationID waypoint_to_join, bool adjacent, TileArea ta, Waypoint **wp)
{
	return FindJoiningBaseStation<Waypoint, STR_ERROR_MUST_REMOVE_RAILWAYPOINT_FIRST>(existing_waypoint, waypoint_to_join, adjacent, ta, wp);
}

/**
 * Clear platform reservation during station building/removing.
 * @param v vehicle which holds reservation
 */
static void FreeTrainReservation(Train *v)
{
	FreeTrainTrackReservation(v);
	if (IsRailStationTile(v->tile)) SetRailStationPlatformReservation(v->tile, TrackdirToExitdir(v->GetVehicleTrackdir()), false);
	v = v->Last();
	if (IsRailStationTile(v->tile)) SetRailStationPlatformReservation(v->tile, TrackdirToExitdir(ReverseTrackdir(v->GetVehicleTrackdir())), false);
}

/**
 * Restore platform reservation during station building/removing.
 * @param v vehicle which held reservation
 */
static void RestoreTrainReservation(Train *v)
{
	if (IsRailStationTile(v->tile)) SetRailStationPlatformReservation(v->tile, TrackdirToExitdir(v->GetVehicleTrackdir()), true);
	TryPathReserve(v, true, true);
	v = v->Last();
	if (IsRailStationTile(v->tile)) SetRailStationPlatformReservation(v->tile, TrackdirToExitdir(ReverseTrackdir(v->GetVehicleTrackdir())), true);
}

/**
 * Build rail station
 * @param tile_org northern most position of station dragging/placement
 * @param flags operation to perform
 * @param p1 various bitstuffed elements
 * - p1 = (bit  0- 3) - railtype
 * - p1 = (bit  4)    - orientation (Axis)
 * - p1 = (bit  8-15) - number of tracks
 * - p1 = (bit 16-23) - platform length
 * - p1 = (bit 24)    - allow stations directly adjacent to other stations.
 * @param p2 various bitstuffed elements
 * - p2 = (bit  0- 7) - custom station class
 * - p2 = (bit  8-15) - custom station id
 * - p2 = (bit 16-31) - station ID to join (NEW_STATION if build new one)
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdBuildRailStation(TileIndex tile_org, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	/* Unpack parameters */
	RailType rt    = Extract<RailType, 0, 4>(p1);
	Axis axis      = Extract<Axis, 4, 1>(p1);
	byte numtracks = GB(p1,  8, 8);
	byte plat_len  = GB(p1, 16, 8);
	bool adjacent  = HasBit(p1, 24);

	StationClassID spec_class = Extract<StationClassID, 0, 8>(p2);
	byte spec_index           = GB(p2, 8, 8);
	StationID station_to_join = GB(p2, 16, 16);

	/* Does the authority allow this? */
	CommandCost ret = CheckIfAuthorityAllowsNewStation(tile_org, flags);
	if (ret.Failed()) return ret;

	if (!ValParamRailtype(rt)) return CMD_ERROR;

	/* Check if the given station class is valid */
	if ((uint)spec_class >= StationClass::GetClassCount() || spec_class == STAT_CLASS_WAYP) return CMD_ERROR;
	if (spec_index >= StationClass::Get(spec_class)->GetSpecCount()) return CMD_ERROR;
	if (plat_len == 0 || numtracks == 0) return CMD_ERROR;

	int w_org, h_org;
	if (axis == AXIS_X) {
		w_org = plat_len;
		h_org = numtracks;
	} else {
		h_org = plat_len;
		w_org = numtracks;
	}

	bool reuse = (station_to_join != NEW_STATION);
	if (!reuse) station_to_join = INVALID_STATION;
	bool distant_join = (station_to_join != INVALID_STATION);

	if (distant_join && (!_settings_game.station.distant_join_stations || !Station::IsValidID(station_to_join))) return CMD_ERROR;

	if (h_org > _settings_game.station.station_spread || w_org > _settings_game.station.station_spread) return CMD_ERROR;

	/* these values are those that will be stored in train_tile and station_platforms */
	TileArea new_location(tile_org, w_org, h_org);

	/* Make sure the area below consists of clear tiles. (OR tiles belonging to a certain rail station) */
	StationID est = INVALID_STATION;
	SmallVector<Train *, 4> affected_vehicles;
	/* Clear the land below the station. */
	CommandCost cost = CheckFlatLandRailStation(new_location, flags, axis, &est, rt, affected_vehicles, spec_class, spec_index, plat_len, numtracks);
	if (cost.Failed()) return cost;
	/* Add construction expenses. */
	cost.AddCost((numtracks * _price[PR_BUILD_STATION_RAIL] + _price[PR_BUILD_STATION_RAIL_LENGTH]) * plat_len);
	cost.AddCost(numtracks * plat_len * RailBuildCost(rt));

	Station *st = NULL;
	ret = FindJoiningStation(est, station_to_join, adjacent, new_location, &st);
	if (ret.Failed()) return ret;

	ret = BuildStationPart(&st, flags, reuse, new_location, STATIONNAMING_RAIL);
	if (ret.Failed()) return ret;

	if (st != NULL && st->train_station.tile != INVALID_TILE) {
		CommandCost ret = CanExpandRailStation(st, new_location, axis);
		if (ret.Failed()) return ret;
	}

	/* Check if we can allocate a custom stationspec to this station */
	const StationSpec *statspec = StationClass::Get(spec_class)->GetSpec(spec_index);
	int specindex = AllocateSpecToStation(statspec, st, (flags & DC_EXEC) != 0);
	if (specindex == -1) return_cmd_error(STR_ERROR_TOO_MANY_STATION_SPECS);

	if (statspec != NULL) {
		/* Perform NewStation checks */

		/* Check if the station size is permitted */
		if (HasBit(statspec->disallowed_platforms, min(numtracks - 1, 7)) || HasBit(statspec->disallowed_lengths, min(plat_len - 1, 7))) {
			return CMD_ERROR;
		}

		/* Check if the station is buildable */
		if (HasBit(statspec->callback_mask, CBM_STATION_AVAIL)) {
			uint16 cb_res = GetStationCallback(CBID_STATION_AVAILABILITY, 0, 0, statspec, NULL, INVALID_TILE);
			if (cb_res != CALLBACK_FAILED && !Convert8bitBooleanCallback(statspec->grf_prop.grffile, CBID_STATION_AVAILABILITY, cb_res)) return CMD_ERROR;
		}
	}

	if (flags & DC_EXEC) {
		TileIndexDiff tile_delta;
		byte *layout_ptr;
		byte numtracks_orig;
		Track track;

		st->train_station = new_location;
		st->AddFacility(FACIL_TRAIN, new_location.tile);

		st->rect.BeforeAddRect(tile_org, w_org, h_org, StationRect::ADD_TRY);

		if (statspec != NULL) {
			/* Include this station spec's animation trigger bitmask
			 * in the station's cached copy. */
			st->cached_anim_triggers |= statspec->animation.triggers;
		}

		tile_delta = (axis == AXIS_X ? TileDiffXY(1, 0) : TileDiffXY(0, 1));
		track = AxisToTrack(axis);

		layout_ptr = AllocaM(byte, numtracks * plat_len);
		GetStationLayout(layout_ptr, numtracks, plat_len, statspec);

		numtracks_orig = numtracks;

		Company *c = Company::Get(st->owner);
		TileIndex tile_track = tile_org;
		do {
			TileIndex tile = tile_track;
			int w = plat_len;
			do {
				byte layout = *layout_ptr++;
				if (IsRailStationTile(tile) && HasStationReservation(tile)) {
					/* Check for trains having a reservation for this tile. */
					Train *v = GetTrainForReservation(tile, AxisToTrack(GetRailStationAxis(tile)));
					if (v != NULL) {
						*affected_vehicles.Append() = v;
						FreeTrainReservation(v);
					}
				}

				/* Railtype can change when overbuilding. */
				if (IsRailStationTile(tile)) {
					if (!IsStationTileBlocked(tile)) c->infrastructure.rail[GetRailType(tile)]--;
					c->infrastructure.station--;
				}

				/* Remove animation if overbuilding */
				DeleteAnimatedTile(tile);
				byte old_specindex = HasStationTileRail(tile) ? GetCustomStationSpecIndex(tile) : 0;
				MakeRailStation(tile, st->owner, st->index, axis, layout & ~1, rt);
				/* Free the spec if we overbuild something */
				DeallocateSpecFromStation(st, old_specindex);

				SetCustomStationSpecIndex(tile, specindex);
				SetStationTileRandomBits(tile, GB(Random(), 0, 4));
				SetAnimationFrame(tile, 0);

				if (!IsStationTileBlocked(tile)) c->infrastructure.rail[rt]++;
				c->infrastructure.station++;

				if (statspec != NULL) {
					/* Use a fixed axis for GetPlatformInfo as our platforms / numtracks are always the right way around */
					uint32 platinfo = GetPlatformInfo(AXIS_X, GetStationGfx(tile), plat_len, numtracks_orig, plat_len - w, numtracks_orig - numtracks, false);

					/* As the station is not yet completely finished, the station does not yet exist. */
					uint16 callback = GetStationCallback(CBID_STATION_TILE_LAYOUT, platinfo, 0, statspec, NULL, tile);
					if (callback != CALLBACK_FAILED) {
						if (callback < 8) {
							SetStationGfx(tile, (callback & ~1) + axis);
						} else {
							ErrorUnknownCallbackResult(statspec->grf_prop.grffile->grfid, CBID_STATION_TILE_LAYOUT, callback);
						}
					}

					/* Trigger station animation -- after building? */
					TriggerStationAnimation(st, tile, SAT_BUILT);
				}

				tile += tile_delta;
			} while (--w);
			AddTrackToSignalBuffer(tile_track, track, _current_company);
			YapfNotifyTrackLayoutChange(tile_track, track);
			tile_track += tile_delta ^ TileDiffXY(1, 1); // perpendicular to tile_delta
		} while (--numtracks);

		for (uint i = 0; i < affected_vehicles.Length(); ++i) {
			/* Restore reservations of trains. */
			RestoreTrainReservation(affected_vehicles[i]);
		}

		/* Check whether we need to expand the reservation of trains already on the station. */
		TileArea update_reservation_area;
		if (axis == AXIS_X) {
			update_reservation_area = TileArea(tile_org, 1, numtracks_orig);
		} else {
			update_reservation_area = TileArea(tile_org, numtracks_orig, 1);
		}

		TILE_AREA_LOOP(tile, update_reservation_area) {
			/* Don't even try to make eye candy parts reserved. */
			if (IsStationTileBlocked(tile)) continue;

			DiagDirection dir = AxisToDiagDir(axis);
			TileIndexDiff tile_offset = TileOffsByDiagDir(dir);
			TileIndex platform_begin = tile;
			TileIndex platform_end = tile;

			/* We can only account for tiles that are reachable from this tile, so ignore primarily blocked tiles while finding the platform begin and end. */
			for (TileIndex next_tile = platform_begin - tile_offset; IsCompatibleTrainStationTile(next_tile, platform_begin); next_tile -= tile_offset) {
				platform_begin = next_tile;
			}
			for (TileIndex next_tile = platform_end + tile_offset; IsCompatibleTrainStationTile(next_tile, platform_end); next_tile += tile_offset) {
				platform_end = next_tile;
			}

			/* If there is at least on reservation on the platform, we reserve the whole platform. */
			bool reservation = false;
			for (TileIndex t = platform_begin; !reservation && t <= platform_end; t += tile_offset) {
				reservation = HasStationReservation(t);
			}

			if (reservation) {
				SetRailStationPlatformReservation(platform_begin, dir, true);
			}
		}

		st->MarkTilesDirty(false);
		st->UpdateVirtCoord();
		UpdateStationAcceptance(st, false);
		st->RecomputeIndustriesNear();
		InvalidateWindowData(WC_SELECT_STATION, 0, 0);
		InvalidateWindowData(WC_STATION_LIST, st->owner, 0);
		SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_TRAINS);
		DirtyCompanyInfrastructureWindows(st->owner);
	}

	return cost;
}

static void MakeRailStationAreaSmaller(BaseStation *st)
{
	TileArea ta = st->train_station;

restart:

	/* too small? */
	if (ta.w != 0 && ta.h != 0) {
		/* check the left side, x = constant, y changes */
		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(0, i));) {
			/* the left side is unused? */
			if (++i == ta.h) {
				ta.tile += TileDiffXY(1, 0);
				ta.w--;
				goto restart;
			}
		}

		/* check the right side, x = constant, y changes */
		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(ta.w - 1, i));) {
			/* the right side is unused? */
			if (++i == ta.h) {
				ta.w--;
				goto restart;
			}
		}

		/* check the upper side, y = constant, x changes */
		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(i, 0));) {
			/* the left side is unused? */
			if (++i == ta.w) {
				ta.tile += TileDiffXY(0, 1);
				ta.h--;
				goto restart;
			}
		}

		/* check the lower side, y = constant, x changes */
		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(i, ta.h - 1));) {
			/* the left side is unused? */
			if (++i == ta.w) {
				ta.h--;
				goto restart;
			}
		}
	} else {
		ta.Clear();
	}

	st->train_station = ta;
}

/**
 * Remove a number of tiles from any rail station within the area.
 * @param ta the area to clear station tile from.
 * @param affected_stations the stations affected.
 * @param flags the command flags.
 * @param removal_cost the cost for removing the tile, including the rail.
 * @param keep_rail whether to keep the rail of the station.
 * @tparam T the type of station to remove.
 * @return the number of cleared tiles or an error.
 */
template <class T>
CommandCost RemoveFromRailBaseStation(TileArea ta, SmallVector<T *, 4> &affected_stations, DoCommandFlag flags, Money removal_cost, bool keep_rail)
{
	/* Count of the number of tiles removed */
	int quantity = 0;
	CommandCost total_cost(EXPENSES_CONSTRUCTION);
	/* Accumulator for the errors seen during clearing. If no errors happen,
	 * and the quantity is 0 there is no station. Otherwise it will be one
	 * of the other error that got accumulated. */
	CommandCost error;

	/* Do the action for every tile into the area */
	TILE_AREA_LOOP(tile, ta) {
		/* Make sure the specified tile is a rail station */
		if (!HasStationTileRail(tile)) continue;

		/* If there is a vehicle on ground, do not allow to remove (flood) the tile */
		CommandCost ret = EnsureNoVehicleOnGround(tile);
		error.AddCost(ret);
		if (ret.Failed()) continue;

		/* Check ownership of station */
		T *st = T::GetByTile(tile);
		if (st == NULL) continue;

		if (_current_company != OWNER_WATER) {
			CommandCost ret = CheckOwnership(st->owner);
			error.AddCost(ret);
			if (ret.Failed()) continue;
		}

		/* If we reached here, the tile is valid so increase the quantity of tiles we will remove */
		quantity++;

		if (keep_rail || IsStationTileBlocked(tile)) {
			/* Don't refund the 'steel' of the track when we keep the
			 *  rail, or when the tile didn't have any rail at all. */
			total_cost.AddCost(-_price[PR_CLEAR_RAIL]);
		}

		if (flags & DC_EXEC) {
			/* read variables before the station tile is removed */
			uint specindex = GetCustomStationSpecIndex(tile);
			Track track = GetRailStationTrack(tile);
			Owner owner = GetTileOwner(tile);
			RailType rt = GetRailType(tile);
			Train *v = NULL;

			if (HasStationReservation(tile)) {
				v = GetTrainForReservation(tile, track);
				if (v != NULL) FreeTrainReservation(v);
			}

			bool build_rail = keep_rail && !IsStationTileBlocked(tile);
			if (!build_rail && !IsStationTileBlocked(tile)) Company::Get(owner)->infrastructure.rail[rt]--;

			DoClearSquare(tile);
			DeleteNewGRFInspectWindow(GSF_STATIONS, tile);
			if (build_rail) MakeRailNormal(tile, owner, TrackToTrackBits(track), rt);
			Company::Get(owner)->infrastructure.station--;
			DirtyCompanyInfrastructureWindows(owner);

			st->rect.AfterRemoveTile(st, tile);
			AddTrackToSignalBuffer(tile, track, owner);
			YapfNotifyTrackLayoutChange(tile, track);

			DeallocateSpecFromStation(st, specindex);

			affected_stations.Include(st);

			if (v != NULL) RestoreTrainReservation(v);
		}
	}

	if (quantity == 0) return error.Failed() ? error : CommandCost(STR_ERROR_THERE_IS_NO_STATION);

	for (T **stp = affected_stations.Begin(); stp != affected_stations.End(); stp++) {
		T *st = *stp;

		/* now we need to make the "spanned" area of the railway station smaller
		 * if we deleted something at the edges.
		 * we also need to adjust train_tile. */
		MakeRailStationAreaSmaller(st);
		UpdateStationSignCoord(st);

		/* if we deleted the whole station, delete the train facility. */
		if (st->train_station.tile == INVALID_TILE) {
			st->facilities &= ~FACIL_TRAIN;
			SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_TRAINS);
			st->UpdateVirtCoord();
			DeleteStationIfEmpty(st);
		}
	}

	total_cost.AddCost(quantity * removal_cost);
	return total_cost;
}

/**
 * Remove a single tile from a rail station.
 * This allows for custom-built station with holes and weird layouts
 * @param start tile of station piece to remove
 * @param flags operation to perform
 * @param p1 start_tile
 * @param p2 various bitstuffed elements
 * - p2 = bit 0 - if set keep the rail
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdRemoveFromRailStation(TileIndex start, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	TileIndex end = p1 == 0 ? start : p1;
	if (start >= MapSize() || end >= MapSize()) return CMD_ERROR;

	TileArea ta(start, end);
	SmallVector<Station *, 4> affected_stations;

	CommandCost ret = RemoveFromRailBaseStation(ta, affected_stations, flags, _price[PR_CLEAR_STATION_RAIL], HasBit(p2, 0));
	if (ret.Failed()) return ret;

	/* Do all station specific functions here. */
	for (Station **stp = affected_stations.Begin(); stp != affected_stations.End(); stp++) {
		Station *st = *stp;

		if (st->train_station.tile == INVALID_TILE) SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_TRAINS);
		st->MarkTilesDirty(false);
		st->RecomputeIndustriesNear();
	}

	/* Now apply the rail cost to the number that we deleted */
	return ret;
}

/**
 * Remove a single tile from a waypoint.
 * This allows for custom-built waypoint with holes and weird layouts
 * @param start tile of waypoint piece to remove
 * @param flags operation to perform
 * @param p1 start_tile
 * @param p2 various bitstuffed elements
 * - p2 = bit 0 - if set keep the rail
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdRemoveFromRailWaypoint(TileIndex start, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	TileIndex end = p1 == 0 ? start : p1;
	if (start >= MapSize() || end >= MapSize()) return CMD_ERROR;

	TileArea ta(start, end);
	SmallVector<Waypoint *, 4> affected_stations;

	return RemoveFromRailBaseStation(ta, affected_stations, flags, _price[PR_CLEAR_WAYPOINT_RAIL], HasBit(p2, 0));
}


/**
 * Remove a rail station/waypoint
 * @param st The station/waypoint to remove the rail part from
 * @param flags operation to perform
 * @param removal_cost the cost for removing a tile
 * @tparam T the type of station to remove
 * @return cost or failure of operation
 */
template <class T>
CommandCost RemoveRailStation(T *st, DoCommandFlag flags, Money removal_cost)
{
	/* Current company owns the station? */
	if (_current_company != OWNER_WATER) {
		CommandCost ret = CheckOwnership(st->owner);
		if (ret.Failed()) return ret;
	}

	/* determine width and height of platforms */
	TileArea ta = st->train_station;

	assert(ta.w != 0 && ta.h != 0);

	CommandCost cost(EXPENSES_CONSTRUCTION);
	/* clear all areas of the station */
	TILE_AREA_LOOP(tile, ta) {
		/* only remove tiles that are actually train station tiles */
		if (st->TileBelongsToRailStation(tile)) {
			SmallVector<T*, 4> affected_stations; // dummy
			CommandCost ret = RemoveFromRailBaseStation(TileArea(tile, 1, 1), affected_stations, flags, removal_cost, false);
			if (ret.Failed()) return ret;
			cost.AddCost(ret);
		}
	}

	return cost;
}

/**
 * Remove a rail station
 * @param tile Tile of the station.
 * @param flags operation to perform
 * @return cost or failure of operation
 */
static CommandCost RemoveRailStation(TileIndex tile, DoCommandFlag flags)
{
	/* if there is flooding, remove platforms tile by tile */
	if (_current_company == OWNER_WATER) {
		return DoCommand(tile, 0, 0, DC_EXEC, CMD_REMOVE_FROM_RAIL_STATION);
	}

	Station *st = Station::GetByTile(tile);
	CommandCost cost = RemoveRailStation(st, flags, _price[PR_CLEAR_STATION_RAIL]);

	if (flags & DC_EXEC) st->RecomputeIndustriesNear();

	return cost;
}

/**
 * Remove a rail waypoint
 * @param tile Tile of the waypoint.
 * @param flags operation to perform
 * @return cost or failure of operation
 */
static CommandCost RemoveRailWaypoint(TileIndex tile, DoCommandFlag flags)
{
	/* if there is flooding, remove waypoints tile by tile */
	if (_current_company == OWNER_WATER) {
		return DoCommand(tile, 0, 0, DC_EXEC, CMD_REMOVE_FROM_RAIL_WAYPOINT);
	}

	return RemoveRailStation(Waypoint::GetByTile(tile), flags, _price[PR_CLEAR_WAYPOINT_RAIL]);
}


/**
 * @param truck_station Determines whether a stop is #ROADSTOP_BUS or #ROADSTOP_TRUCK
 * @param st The Station to do the whole procedure for
 * @return a pointer to where to link a new RoadStop*
 */
static RoadStop **FindRoadStopSpot(bool truck_station, Station *st)
{
	RoadStop **primary_stop = (truck_station) ? &st->truck_stops : &st->bus_stops;

	if (*primary_stop == NULL) {
		/* we have no roadstop of the type yet, so write a "primary stop" */
		return primary_stop;
	} else {
		/* there are stops already, so append to the end of the list */
		RoadStop *stop = *primary_stop;
		while (stop->next != NULL) stop = stop->next;
		return &stop->next;
	}
}

static CommandCost RemoveRoadStop(TileIndex tile, DoCommandFlag flags);

/**
 * Find a nearby station that joins this road stop.
 * @param existing_stop an existing road stop we build over
 * @param station_to_join the station to join to
 * @param adjacent whether adjacent stations are allowed
 * @param ta the area of the newly build station
 * @param st 'return' pointer for the found station
 * @return command cost with the error or 'okay'
 */
static CommandCost FindJoiningRoadStop(StationID existing_stop, StationID station_to_join, bool adjacent, TileArea ta, Station **st)
{
	return FindJoiningBaseStation<Station, STR_ERROR_MUST_REMOVE_ROAD_STOP_FIRST>(existing_stop, station_to_join, adjacent, ta, st);
}

/**
 * Build a bus or truck stop.
 * @param tile Northernmost tile of the stop.
 * @param flags Operation to perform.
 * @param p1 bit 0..7: Width of the road stop.
 *           bit 8..15: Length of the road stop.
 * @param p2 bit 0: 0 For bus stops, 1 for truck stops.
 *           bit 1: 0 For normal stops, 1 for drive-through.
 *           bit 2..3: The roadtypes.
 *           bit 5: Allow stations directly adjacent to other stations.
 *           bit 6..7: Entrance direction (#DiagDirection) for normal stops.
 *           bit 6: #Axis of the road for drive-through stops.
 *           bit 16..31: Station ID to join (NEW_STATION if build new one).
 * @param text Unused.
 * @return The cost of this operation or an error.
 */
CommandCost CmdBuildRoadStop(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	bool type = HasBit(p2, 0);
	bool is_drive_through = HasBit(p2, 1);
	RoadTypes rts = Extract<RoadTypes, 2, 2>(p2);
	StationID station_to_join = GB(p2, 16, 16);
	bool reuse = (station_to_join != NEW_STATION);
	if (!reuse) station_to_join = INVALID_STATION;
	bool distant_join = (station_to_join != INVALID_STATION);

	uint8 width = (uint8)GB(p1, 0, 8);
	uint8 lenght = (uint8)GB(p1, 8, 8);

	/* Check if the requested road stop is too big */
	if (width > _settings_game.station.station_spread || lenght > _settings_game.station.station_spread) return_cmd_error(STR_ERROR_STATION_TOO_SPREAD_OUT);
	/* Check for incorrect width / length. */
	if (width == 0 || lenght == 0) return CMD_ERROR;
	/* Check if the first tile and the last tile are valid */
	if (!IsValidTile(tile) || TileAddWrap(tile, width - 1, lenght - 1) == INVALID_TILE) return CMD_ERROR;

	TileArea roadstop_area(tile, width, lenght);

	if (distant_join && (!_settings_game.station.distant_join_stations || !Station::IsValidID(station_to_join))) return CMD_ERROR;

	if (!HasExactlyOneBit(rts) || !HasRoadTypesAvail(_current_company, rts)) return CMD_ERROR;

	/* Trams only have drive through stops */
	if (!is_drive_through && HasBit(rts, ROADTYPE_TRAM)) return CMD_ERROR;

	DiagDirection ddir;
	Axis axis;
	if (is_drive_through) {
		/* By definition axis is valid, due to there being 2 axes and reading 1 bit. */
		axis = Extract<Axis, 6, 1>(p2);
		ddir = AxisToDiagDir(axis);
	} else {
		/* By definition ddir is valid, due to there being 4 diagonal directions and reading 2 bits. */
		ddir = Extract<DiagDirection, 6, 2>(p2);
		axis = DiagDirToAxis(ddir);
	}

	CommandCost ret = CheckIfAuthorityAllowsNewStation(tile, flags);
	if (ret.Failed()) return ret;

	/* Total road stop cost. */
	CommandCost cost(EXPENSES_CONSTRUCTION, roadstop_area.w * roadstop_area.h * _price[type ? PR_BUILD_STATION_TRUCK : PR_BUILD_STATION_BUS]);
	StationID est = INVALID_STATION;
	ret = CheckFlatLandRoadStop(roadstop_area, flags, is_drive_through ? 5 << axis : 1 << ddir, is_drive_through, type, axis, &est, rts);
	if (ret.Failed()) return ret;
	cost.AddCost(ret);

	Station *st = NULL;
	ret = FindJoiningRoadStop(est, station_to_join, HasBit(p2, 5), roadstop_area, &st);
	if (ret.Failed()) return ret;

	/* Check if this number of road stops can be allocated. */
	if (!RoadStop::CanAllocateItem(roadstop_area.w * roadstop_area.h)) return_cmd_error(type ? STR_ERROR_TOO_MANY_TRUCK_STOPS : STR_ERROR_TOO_MANY_BUS_STOPS);

	ret = BuildStationPart(&st, flags, reuse, roadstop_area, STATIONNAMING_ROAD);
	if (ret.Failed()) return ret;

	if (flags & DC_EXEC) {
		/* Check every tile in the area. */
		TILE_AREA_LOOP(cur_tile, roadstop_area) {
			RoadTypes cur_rts = GetRoadTypes(cur_tile);
			Owner road_owner = HasBit(cur_rts, ROADTYPE_ROAD) ? GetRoadOwner(cur_tile, ROADTYPE_ROAD) : _current_company;
			Owner tram_owner = HasBit(cur_rts, ROADTYPE_TRAM) ? GetRoadOwner(cur_tile, ROADTYPE_TRAM) : _current_company;

			if (IsTileType(cur_tile, MP_STATION) && IsRoadStop(cur_tile)) {
				RemoveRoadStop(cur_tile, flags);
			}

			RoadStop *road_stop = new RoadStop(cur_tile);
			/* Insert into linked list of RoadStops. */
			RoadStop **currstop = FindRoadStopSpot(type, st);
			*currstop = road_stop;

			if (type) {
				st->truck_station.Add(cur_tile);
			} else {
				st->bus_station.Add(cur_tile);
			}

			/* Initialize an empty station. */
			st->AddFacility((type) ? FACIL_TRUCK_STOP : FACIL_BUS_STOP, cur_tile);

			st->rect.BeforeAddTile(cur_tile, StationRect::ADD_TRY);

			RoadStopType rs_type = type ? ROADSTOP_TRUCK : ROADSTOP_BUS;
			if (is_drive_through) {
				/* Update company infrastructure counts. If the current tile is a normal
				 * road tile, count only the new road bits needed to get a full diagonal road. */
				RoadType rt;
				FOR_EACH_SET_ROADTYPE(rt, cur_rts | rts) {
					Company *c = Company::GetIfValid(rt == ROADTYPE_ROAD ? road_owner : tram_owner);
					if (c != NULL) {
						c->infrastructure.road[rt] += 2 - (IsNormalRoadTile(cur_tile) && HasBit(cur_rts, rt) ? CountBits(GetRoadBits(cur_tile, rt)) : 0);
						DirtyCompanyInfrastructureWindows(c->index);
					}
				}

				MakeDriveThroughRoadStop(cur_tile, st->owner, road_owner, tram_owner, st->index, rs_type, rts | cur_rts, axis);
				road_stop->MakeDriveThrough();
			} else {
				/* Non-drive-through stop never overbuild and always count as two road bits. */
				Company::Get(st->owner)->infrastructure.road[FIND_FIRST_BIT(rts)] += 2;
				MakeRoadStop(cur_tile, st->owner, st->index, rs_type, rts, ddir);
			}
			Company::Get(st->owner)->infrastructure.station++;
			DirtyCompanyInfrastructureWindows(st->owner);

			MarkTileDirtyByTile(cur_tile);
		}
	}

	if (st != NULL) {
		st->UpdateVirtCoord();
		UpdateStationAcceptance(st, false);
		st->RecomputeIndustriesNear();
		InvalidateWindowData(WC_SELECT_STATION, 0, 0);
		InvalidateWindowData(WC_STATION_LIST, st->owner, 0);
		SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_ROADVEHS);
	}
	return cost;
}


static Vehicle *ClearRoadStopStatusEnum(Vehicle *v, void *)
{
	if (v->type == VEH_ROAD) {
		/* Okay... we are a road vehicle on a drive through road stop.
		 * But that road stop has just been removed, so we need to make
		 * sure we are in a valid state... however, vehicles can also
		 * turn on road stop tiles, so only clear the 'road stop' state
		 * bits and only when the state was 'in road stop', otherwise
		 * we'll end up clearing the turn around bits. */
		RoadVehicle *rv = RoadVehicle::From(v);
		if (HasBit(rv->state, RVS_IN_DT_ROAD_STOP)) rv->state &= RVSB_ROAD_STOP_TRACKDIR_MASK;
	}

	return NULL;
}


/**
 * Remove a bus station/truck stop
 * @param tile TileIndex been queried
 * @param flags operation to perform
 * @return cost or failure of operation
 */
static CommandCost RemoveRoadStop(TileIndex tile, DoCommandFlag flags)
{
	Station *st = Station::GetByTile(tile);

	if (_current_company != OWNER_WATER) {
		CommandCost ret = CheckOwnership(st->owner);
		if (ret.Failed()) return ret;
	}

	bool is_truck = IsTruckStop(tile);

	RoadStop **primary_stop;
	RoadStop *cur_stop;
	if (is_truck) { // truck stop
		primary_stop = &st->truck_stops;
		cur_stop = RoadStop::GetByTile(tile, ROADSTOP_TRUCK);
	} else {
		primary_stop = &st->bus_stops;
		cur_stop = RoadStop::GetByTile(tile, ROADSTOP_BUS);
	}

	assert(cur_stop != NULL);

	/* don't do the check for drive-through road stops when company bankrupts */
	if (IsDriveThroughStopTile(tile) && (flags & DC_BANKRUPT)) {
		/* remove the 'going through road stop' status from all vehicles on that tile */
		if (flags & DC_EXEC) FindVehicleOnPos(tile, NULL, &ClearRoadStopStatusEnum);
	} else {
		CommandCost ret = EnsureNoVehicleOnGround(tile);
		if (ret.Failed()) return ret;
	}

	if (flags & DC_EXEC) {
		if (*primary_stop == cur_stop) {
			/* removed the first stop in the list */
			*primary_stop = cur_stop->next;
			/* removed the only stop? */
			if (*primary_stop == NULL) {
				st->facilities &= (is_truck ? ~FACIL_TRUCK_STOP : ~FACIL_BUS_STOP);
			}
		} else {
			/* tell the predecessor in the list to skip this stop */
			RoadStop *pred = *primary_stop;
			while (pred->next != cur_stop) pred = pred->next;
			pred->next = cur_stop->next;
		}

		/* Update company infrastructure counts. */
		RoadType rt;
		FOR_EACH_SET_ROADTYPE(rt, GetRoadTypes(tile)) {
			Company *c = Company::GetIfValid(GetRoadOwner(tile, rt));
			if (c != NULL) {
				c->infrastructure.road[rt] -= 2;
				DirtyCompanyInfrastructureWindows(c->index);
			}
		}
		Company::Get(st->owner)->infrastructure.station--;
		DirtyCompanyInfrastructureWindows(st->owner);

		if (IsDriveThroughStopTile(tile)) {
			/* Clears the tile for us */
			cur_stop->ClearDriveThrough();
		} else {
			DoClearSquare(tile);
		}

		SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_ROADVEHS);
		delete cur_stop;

		/* Make sure no vehicle is going to the old roadstop */
		RoadVehicle *v;
		FOR_ALL_ROADVEHICLES(v) {
			if (v->First() == v && v->current_order.IsType(OT_GOTO_STATION) &&
					v->dest_tile == tile) {
				v->dest_tile = v->GetOrderStationLocation(st->index);
			}
		}

		st->rect.AfterRemoveTile(st, tile);

		st->UpdateVirtCoord();
		st->RecomputeIndustriesNear();
		DeleteStationIfEmpty(st);

		/* Update the tile area of the truck/bus stop */
		if (is_truck) {
			st->truck_station.Clear();
			for (const RoadStop *rs = st->truck_stops; rs != NULL; rs = rs->next) st->truck_station.Add(rs->xy);
		} else {
			st->bus_station.Clear();
			for (const RoadStop *rs = st->bus_stops; rs != NULL; rs = rs->next) st->bus_station.Add(rs->xy);
		}
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[is_truck ? PR_CLEAR_STATION_TRUCK : PR_CLEAR_STATION_BUS]);
}

/**
 * Remove bus or truck stops.
 * @param tile Northernmost tile of the removal area.
 * @param flags Operation to perform.
 * @param p1 bit 0..7: Width of the removal area.
 *           bit 8..15: Height of the removal area.
 * @param p2 bit 0: 0 For bus stops, 1 for truck stops.
 * @param p2 bit 1: 0 to keep roads of all drive-through stops, 1 to remove them.
 * @param text Unused.
 * @return The cost of this operation or an error.
 */
CommandCost CmdRemoveRoadStop(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	uint8 width = (uint8)GB(p1, 0, 8);
	uint8 height = (uint8)GB(p1, 8, 8);
	bool keep_drive_through_roads = !HasBit(p2, 1);

	/* Check for incorrect width / height. */
	if (width == 0 || height == 0) return CMD_ERROR;
	/* Check if the first tile and the last tile are valid */
	if (!IsValidTile(tile) || TileAddWrap(tile, width - 1, height - 1) == INVALID_TILE) return CMD_ERROR;
	/* Bankrupting company is not supposed to remove roads, there may be road vehicles. */
	if (!keep_drive_through_roads && (flags & DC_BANKRUPT)) return CMD_ERROR;

	TileArea roadstop_area(tile, width, height);

	CommandCost cost(EXPENSES_CONSTRUCTION);
	CommandCost last_error(STR_ERROR_THERE_IS_NO_STATION);
	bool had_success = false;

	TILE_AREA_LOOP(cur_tile, roadstop_area) {
		/* Make sure the specified tile is a road stop of the correct type */
		if (!IsTileType(cur_tile, MP_STATION) || !IsRoadStop(cur_tile) || (uint32)GetRoadStopType(cur_tile) != GB(p2, 0, 1)) continue;

		/* Save information on to-be-restored roads before the stop is removed. */
		RoadTypes rts = ROADTYPES_NONE;
		RoadBits road_bits = ROAD_NONE;
		Owner road_owner[] = { OWNER_NONE, OWNER_NONE };
		assert_compile(lengthof(road_owner) == ROADTYPE_END);
		if (IsDriveThroughStopTile(cur_tile)) {
			RoadType rt;
			FOR_EACH_SET_ROADTYPE(rt, GetRoadTypes(cur_tile)) {
				road_owner[rt] = GetRoadOwner(cur_tile, rt);
				/* If we don't want to preserve our roads then restore only roads of others. */
				if (keep_drive_through_roads || road_owner[rt] != _current_company) SetBit(rts, rt);
			}
			road_bits = AxisToRoadBits(DiagDirToAxis(GetRoadStopDir(cur_tile)));
		}

		CommandCost ret = RemoveRoadStop(cur_tile, flags);
		if (ret.Failed()) {
			last_error = ret;
			continue;
		}
		cost.AddCost(ret);
		had_success = true;

		/* Restore roads. */
		if ((flags & DC_EXEC) && rts != ROADTYPES_NONE) {
			MakeRoadNormal(cur_tile, road_bits, rts, ClosestTownFromTile(cur_tile, UINT_MAX)->index,
					road_owner[ROADTYPE_ROAD], road_owner[ROADTYPE_TRAM]);

			/* Update company infrastructure counts. */
			RoadType rt;
			FOR_EACH_SET_ROADTYPE(rt, rts) {
				Company *c = Company::GetIfValid(GetRoadOwner(cur_tile, rt));
				if (c != NULL) {
					c->infrastructure.road[rt] += CountBits(road_bits);
					DirtyCompanyInfrastructureWindows(c->index);
				}
			}
		}
	}

	return had_success ? cost : last_error;
}

/**
 * Computes the minimal distance from town's xy to any airport's tile.
 * @param it An iterator over all airport tiles.
 * @param town_tile town's tile (t->xy)
 * @return minimal manhattan distance from town_tile to any airport's tile
 */
static uint GetMinimalAirportDistanceToTile(TileIterator &it, TileIndex town_tile)
{
	uint mindist = UINT_MAX;

	for (TileIndex cur_tile = it; cur_tile != INVALID_TILE; cur_tile = ++it) {
		mindist = min(mindist, DistanceManhattan(town_tile, cur_tile));
	}

	return mindist;
}

/**
 * Get a possible noise reduction factor based on distance from town center.
 * The further you get, the less noise you generate.
 * So all those folks at city council can now happily slee...  work in their offices
 * @param as airport information
 * @param it An iterator over all airport tiles.
 * @param town_tile TileIndex of town's center, the one who will receive the airport's candidature
 * @return the noise that will be generated, according to distance
 */
uint8 GetAirportNoiseLevelForTown(const AirportSpec *as, TileIterator &it, TileIndex town_tile)
{
	/* 0 cannot be accounted, and 1 is the lowest that can be reduced from town.
	 * So no need to go any further*/
	if (as->noise_level < 2) return as->noise_level;

	uint distance = GetMinimalAirportDistanceToTile(it, town_tile);

	/* The steps for measuring noise reduction are based on the "magical" (and arbitrary) 8 base distance
	 * adding the town_council_tolerance 4 times, as a way to graduate, depending of the tolerance.
	 * Basically, it says that the less tolerant a town is, the bigger the distance before
	 * an actual decrease can be granted */
	uint8 town_tolerance_distance = 8 + (_settings_game.difficulty.town_council_tolerance * 4);

	/* now, we want to have the distance segmented using the distance judged bareable by town
	 * This will give us the coefficient of reduction the distance provides. */
	uint noise_reduction = distance / town_tolerance_distance;

	/* If the noise reduction equals the airport noise itself, don't give it for free.
	 * Otherwise, simply reduce the airport's level. */
	return noise_reduction >= as->noise_level ? 1 : as->noise_level - noise_reduction;
}

/**
 * Finds the town nearest to given airport. Based on minimal manhattan distance to any airport's tile.
 * If two towns have the same distance, town with lower index is returned.
 * @param as airport's description
 * @param it An iterator over all airport tiles
 * @return nearest town to airport
 */
Town *AirportGetNearestTown(const AirportSpec *as, const TileIterator &it)
{
	Town *t, *nearest = NULL;
	uint add = as->size_x + as->size_y - 2; // GetMinimalAirportDistanceToTile can differ from DistanceManhattan by this much
	uint mindist = UINT_MAX - add; // prevent overflow
	FOR_ALL_TOWNS(t) {
		if (DistanceManhattan(t->xy, it) < mindist + add) { // avoid calling GetMinimalAirportDistanceToTile too often
			TileIterator *copy = it.Clone();
			uint dist = GetMinimalAirportDistanceToTile(*copy, t->xy);
			delete copy;
			if (dist < mindist) {
				nearest = t;
				mindist = dist;
			}
		}
	}

	return nearest;
}


/** Recalculate the noise generated by the airports of each town */
void UpdateAirportsNoise()
{
	Town *t;
	const Station *st;

	FOR_ALL_TOWNS(t) t->noise_reached = 0;

	FOR_ALL_STATIONS(st) {
		if (st->airport.tile != INVALID_TILE && st->airport.type != AT_OILRIG) {
			const AirportSpec *as = st->airport.GetSpec();
			AirportTileIterator it(st);
			Town *nearest = AirportGetNearestTown(as, it);
			nearest->noise_reached += GetAirportNoiseLevelForTown(as, it, nearest->xy);
		}
	}
}

/**
 * Place an Airport.
 * @param tile tile where airport will be built
 * @param flags operation to perform
 * @param p1
 * - p1 = (bit  0- 7) - airport type, @see airport.h
 * - p1 = (bit  8-15) - airport layout
 * @param p2 various bitstuffed elements
 * - p2 = (bit     0) - allow airports directly adjacent to other airports.
 * - p2 = (bit 16-31) - station ID to join (NEW_STATION if build new one)
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdBuildAirport(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	StationID station_to_join = GB(p2, 16, 16);
	bool reuse = (station_to_join != NEW_STATION);
	if (!reuse) station_to_join = INVALID_STATION;
	bool distant_join = (station_to_join != INVALID_STATION);
	byte airport_type = GB(p1, 0, 8);
	byte layout = GB(p1, 8, 8);

	if (distant_join && (!_settings_game.station.distant_join_stations || !Station::IsValidID(station_to_join))) return CMD_ERROR;

	if (airport_type >= NUM_AIRPORTS) return CMD_ERROR;

	CommandCost ret = CheckIfAuthorityAllowsNewStation(tile, flags);
	if (ret.Failed()) return ret;

	/* Check if a valid, buildable airport was chosen for construction */
	const AirportSpec *as = AirportSpec::Get(airport_type);
	if (!as->IsAvailable() || layout >= as->num_table) return CMD_ERROR;

	Direction rotation = as->rotation[layout];
	int w = as->size_x;
	int h = as->size_y;
	if (rotation == DIR_E || rotation == DIR_W) Swap(w, h);
	TileArea airport_area = TileArea(tile, w, h);

	if (w > _settings_game.station.station_spread || h > _settings_game.station.station_spread) {
		return_cmd_error(STR_ERROR_STATION_TOO_SPREAD_OUT);
	}

	CommandCost cost = CheckFlatLand(airport_area, flags);
	if (cost.Failed()) return cost;

	/* The noise level is the noise from the airport and reduce it to account for the distance to the town center. */
	AirportTileTableIterator iter(as->table[layout], tile);
	Town *nearest = AirportGetNearestTown(as, iter);
	uint newnoise_level = GetAirportNoiseLevelForTown(as, iter, nearest->xy);

	/* Check if local auth would allow a new airport */
	StringID authority_refuse_message = STR_NULL;
	Town *authority_refuse_town = NULL;

	if (_settings_game.economy.station_noise_level) {
		/* do not allow to build a new airport if this raise the town noise over the maximum allowed by town */
		if ((nearest->noise_reached + newnoise_level) > nearest->MaxTownNoise()) {
			authority_refuse_message = STR_ERROR_LOCAL_AUTHORITY_REFUSES_NOISE;
			authority_refuse_town = nearest;
		}
	} else {
		Town *t = ClosestTownFromTile(tile, UINT_MAX);
		uint num = 0;
		const Station *st;
		FOR_ALL_STATIONS(st) {
			if (st->town == t && (st->facilities & FACIL_AIRPORT) && st->airport.type != AT_OILRIG) num++;
		}
		if (num >= 2) {
			authority_refuse_message = STR_ERROR_LOCAL_AUTHORITY_REFUSES_AIRPORT;
			authority_refuse_town = t;
		}
	}

	if (authority_refuse_message != STR_NULL) {
		SetDParam(0, authority_refuse_town->index);
		return_cmd_error(authority_refuse_message);
	}

	Station *st = NULL;
	ret = FindJoiningStation(INVALID_STATION, station_to_join, HasBit(p2, 0), airport_area, &st);
	if (ret.Failed()) return ret;

	/* Distant join */
	if (st == NULL && distant_join) st = Station::GetIfValid(station_to_join);

	ret = BuildStationPart(&st, flags, reuse, airport_area, (GetAirport(airport_type)->flags & AirportFTAClass::AIRPLANES) ? STATIONNAMING_AIRPORT : STATIONNAMING_HELIPORT);
	if (ret.Failed()) return ret;

	if (st != NULL && st->airport.tile != INVALID_TILE) {
		return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_AIRPORT);
	}

	for (AirportTileTableIterator iter(as->table[layout], tile); iter != INVALID_TILE; ++iter) {
		cost.AddCost(_price[PR_BUILD_STATION_AIRPORT]);
	}

	if (flags & DC_EXEC) {
		/* Always add the noise, so there will be no need to recalculate when option toggles */
		nearest->noise_reached += newnoise_level;

		st->AddFacility(FACIL_AIRPORT, tile);
		st->airport.type = airport_type;
		st->airport.layout = layout;
		st->airport.flags = 0;
		st->airport.rotation = rotation;

		st->rect.BeforeAddRect(tile, w, h, StationRect::ADD_TRY);

		for (AirportTileTableIterator iter(as->table[layout], tile); iter != INVALID_TILE; ++iter) {
			MakeAirport(iter, st->owner, st->index, iter.GetStationGfx(), WATER_CLASS_INVALID);
			SetStationTileRandomBits(iter, GB(Random(), 0, 4));
			st->airport.Add(iter);

			if (AirportTileSpec::Get(GetTranslatedAirportTileID(iter.GetStationGfx()))->animation.status != ANIM_STATUS_NO_ANIMATION) AddAnimatedTile(iter);
		}

		/* Only call the animation trigger after all tiles have been built */
		for (AirportTileTableIterator iter(as->table[layout], tile); iter != INVALID_TILE; ++iter) {
			AirportTileAnimationTrigger(st, iter, AAT_BUILT);
		}

		UpdateAirplanesOnNewStation(st);

		Company::Get(st->owner)->infrastructure.airport++;
		DirtyCompanyInfrastructureWindows(st->owner);

		st->UpdateVirtCoord();
		UpdateStationAcceptance(st, false);
		st->RecomputeIndustriesNear();
		InvalidateWindowData(WC_SELECT_STATION, 0, 0);
		InvalidateWindowData(WC_STATION_LIST, st->owner, 0);
		InvalidateWindowData(WC_STATION_VIEW, st->index, -1);

		if (_settings_game.economy.station_noise_level) {
			SetWindowDirty(WC_TOWN_VIEW, st->town->index);
		}
	}

	return cost;
}

/**
 * Remove an airport
 * @param tile TileIndex been queried
 * @param flags operation to perform
 * @return cost or failure of operation
 */
static CommandCost RemoveAirport(TileIndex tile, DoCommandFlag flags)
{
	Station *st = Station::GetByTile(tile);

	if (_current_company != OWNER_WATER) {
		CommandCost ret = CheckOwnership(st->owner);
		if (ret.Failed()) return ret;
	}

	tile = st->airport.tile;

	CommandCost cost(EXPENSES_CONSTRUCTION);

	const Aircraft *a;
	FOR_ALL_AIRCRAFT(a) {
		if (!a->IsNormalAircraft()) continue;
		if (a->targetairport == st->index && a->state != FLYING) return CMD_ERROR;
	}

	if (flags & DC_EXEC) {
		const AirportSpec *as = st->airport.GetSpec();
		/* The noise level is the noise from the airport and reduce it to account for the distance to the town center.
		 * And as for construction, always remove it, even if the setting is not set, in order to avoid the
		 * need of recalculation */
		AirportTileIterator it(st);
		Town *nearest = AirportGetNearestTown(as, it);
		nearest->noise_reached -= GetAirportNoiseLevelForTown(as, it, nearest->xy);
	}

	TILE_AREA_LOOP(tile_cur, st->airport) {
		if (!st->TileBelongsToAirport(tile_cur)) continue;

		CommandCost ret = EnsureNoVehicleOnGround(tile_cur);
		if (ret.Failed()) return ret;

		cost.AddCost(_price[PR_CLEAR_STATION_AIRPORT]);

		if (flags & DC_EXEC) {
			if (IsHangarTile(tile_cur)) OrderBackup::Reset(tile_cur, false);
			DeleteAnimatedTile(tile_cur);
			DoClearSquare(tile_cur);
			DeleteNewGRFInspectWindow(GSF_AIRPORTTILES, tile_cur);
		}
	}

	if (flags & DC_EXEC) {
		/* Clear the persistent storage. */
		delete st->airport.psa;

		for (uint i = 0; i < st->airport.GetNumHangars(); ++i) {
			DeleteWindowById(
				WC_VEHICLE_DEPOT, st->airport.GetHangarTile(i)
			);
		}

		st->rect.AfterRemoveRect(st, st->airport);

		st->airport.Clear();
		st->facilities &= ~FACIL_AIRPORT;

		InvalidateWindowData(WC_STATION_VIEW, st->index, -1);

		if (_settings_game.economy.station_noise_level) {
			SetWindowDirty(WC_TOWN_VIEW, st->town->index);
		}

		Company::Get(st->owner)->infrastructure.airport--;
		DirtyCompanyInfrastructureWindows(st->owner);

		st->UpdateVirtCoord();
		st->RecomputeIndustriesNear();
		DeleteStationIfEmpty(st);
		DeleteNewGRFInspectWindow(GSF_AIRPORTS, st->index);
	}

	return cost;
}

/**
 * Open/close an airport to incoming aircraft.
 * @param tile Unused.
 * @param flags Operation to perform.
 * @param p1 Station ID of the airport.
 * @param p2 Unused.
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdOpenCloseAirport(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	if (!Station::IsValidID(p1)) return CMD_ERROR;
	Station *st = Station::Get(p1);

	if (!(st->facilities & FACIL_AIRPORT) || st->owner == OWNER_NONE) return CMD_ERROR;

	CommandCost ret = CheckOwnership(st->owner);
	if (ret.Failed()) return ret;

	if (flags & DC_EXEC) {
		st->airport.flags ^= AIRPORT_CLOSED_block;
		SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_CLOSE_AIRPORT);
	}
	return CommandCost();
}

/**
 * Tests whether the company's vehicles have this station in orders
 * @param station station ID
 * @param include_company If true only check vehicles of \a company, if false only check vehicles of other companies
 * @param company company ID
 */
bool HasStationInUse(StationID station, bool include_company, CompanyID company)
{
	const Vehicle *v;
	FOR_ALL_VEHICLES(v) {
		if ((v->owner == company) == include_company) {
			const Order *order;
			FOR_VEHICLE_ORDERS(v, order) {
				if ((order->IsType(OT_GOTO_STATION) || order->IsType(OT_GOTO_WAYPOINT)) && order->GetDestination() == station) {
					return true;
				}
			}
		}
	}
	return false;
}

static const TileIndexDiffC _dock_tileoffs_chkaround[] = {
	{-1,  0},
	{ 0,  0},
	{ 0,  0},
	{ 0, -1}
};
static const byte _dock_w_chk[4] = { 2, 1, 2, 1 };
static const byte _dock_h_chk[4] = { 1, 2, 1, 2 };

/**
 * Build a dock/haven.
 * @param tile tile where dock will be built
 * @param flags operation to perform
 * @param p1 (bit 0) - allow docks directly adjacent to other docks.
 * @param p2 bit 16-31: station ID to join (NEW_STATION if build new one)
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdBuildDock(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	StationID station_to_join = GB(p2, 16, 16);
	bool reuse = (station_to_join != NEW_STATION);
	if (!reuse) station_to_join = INVALID_STATION;
	bool distant_join = (station_to_join != INVALID_STATION);

	if (distant_join && (!_settings_game.station.distant_join_stations || !Station::IsValidID(station_to_join))) return CMD_ERROR;

	DiagDirection direction = GetInclinedSlopeDirection(GetTileSlope(tile));
	if (direction == INVALID_DIAGDIR) return_cmd_error(STR_ERROR_SITE_UNSUITABLE);
	direction = ReverseDiagDir(direction);

	/* Docks cannot be placed on rapids */
	if (HasTileWaterGround(tile)) return_cmd_error(STR_ERROR_SITE_UNSUITABLE);

	CommandCost ret = CheckIfAuthorityAllowsNewStation(tile, flags);
	if (ret.Failed()) return ret;

	if (IsBridgeAbove(tile)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);

	ret = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
	if (ret.Failed()) return ret;

	TileIndex tile_cur = tile + TileOffsByDiagDir(direction);

	if (!IsTileType(tile_cur, MP_WATER) || !IsTileFlat(tile_cur)) {
		return_cmd_error(STR_ERROR_SITE_UNSUITABLE);
	}

	if (IsBridgeAbove(tile_cur)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);

	/* Get the water class of the water tile before it is cleared.*/
	WaterClass wc = GetWaterClass(tile_cur);

	ret = DoCommand(tile_cur, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
	if (ret.Failed()) return ret;

	tile_cur += TileOffsByDiagDir(direction);
	if (!IsTileType(tile_cur, MP_WATER) || !IsTileFlat(tile_cur)) {
		return_cmd_error(STR_ERROR_SITE_UNSUITABLE);
	}

	TileArea dock_area = TileArea(tile + ToTileIndexDiff(_dock_tileoffs_chkaround[direction]),
			_dock_w_chk[direction], _dock_h_chk[direction]);

	/* middle */
	Station *st = NULL;
	ret = FindJoiningStation(INVALID_STATION, station_to_join, HasBit(p1, 0), dock_area, &st);
	if (ret.Failed()) return ret;

	/* Distant join */
	if (st == NULL && distant_join) st = Station::GetIfValid(station_to_join);

	ret = BuildStationPart(&st, flags, reuse, dock_area, STATIONNAMING_DOCK);
	if (ret.Failed()) return ret;

	if (st != NULL && st->dock_tile != INVALID_TILE) return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_DOCK);

	if (flags & DC_EXEC) {
		st->dock_tile = tile;
		st->AddFacility(FACIL_DOCK, tile);

		st->rect.BeforeAddRect(dock_area.tile, dock_area.w, dock_area.h, StationRect::ADD_TRY);

		/* If the water part of the dock is on a canal, update infrastructure counts.
		 * This is needed as we've unconditionally cleared that tile before. */
		if (wc == WATER_CLASS_CANAL) {
			Company::Get(st->owner)->infrastructure.water++;
		}
		Company::Get(st->owner)->infrastructure.station += 2;
		DirtyCompanyInfrastructureWindows(st->owner);

		MakeDock(tile, st->owner, st->index, direction, wc);

		st->UpdateVirtCoord();
		UpdateStationAcceptance(st, false);
		st->RecomputeIndustriesNear();
		InvalidateWindowData(WC_SELECT_STATION, 0, 0);
		InvalidateWindowData(WC_STATION_LIST, st->owner, 0);
		SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_SHIPS);
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_STATION_DOCK]);
}

/**
 * Remove a dock
 * @param tile TileIndex been queried
 * @param flags operation to perform
 * @return cost or failure of operation
 */
static CommandCost RemoveDock(TileIndex tile, DoCommandFlag flags)
{
	Station *st = Station::GetByTile(tile);
	CommandCost ret = CheckOwnership(st->owner);
	if (ret.Failed()) return ret;

	TileIndex docking_location = TILE_ADD(st->dock_tile, ToTileIndexDiff(GetDockOffset(st->dock_tile)));

	TileIndex tile1 = st->dock_tile;
	TileIndex tile2 = tile1 + TileOffsByDiagDir(GetDockDirection(tile1));

	ret = EnsureNoVehicleOnGround(tile1);
	if (ret.Succeeded()) ret = EnsureNoVehicleOnGround(tile2);
	if (ret.Failed()) return ret;

	if (flags & DC_EXEC) {
		DoClearSquare(tile1);
		MarkTileDirtyByTile(tile1);
		MakeWaterKeepingClass(tile2, st->owner);

		st->rect.AfterRemoveTile(st, tile1);
		st->rect.AfterRemoveTile(st, tile2);

		st->dock_tile = INVALID_TILE;
		st->facilities &= ~FACIL_DOCK;

		Company::Get(st->owner)->infrastructure.station -= 2;
		DirtyCompanyInfrastructureWindows(st->owner);

		SetWindowWidgetDirty(WC_STATION_VIEW, st->index, WID_SV_SHIPS);
		st->UpdateVirtCoord();
		st->RecomputeIndustriesNear();
		DeleteStationIfEmpty(st);

		/* All ships that were going to our station, can't go to it anymore.
		 * Just clear the order, then automatically the next appropriate order
		 * will be selected and in case of no appropriate order it will just
		 * wander around the world. */
		Ship *s;
		FOR_ALL_SHIPS(s) {
			if (s->current_order.IsType(OT_LOADING) && s->tile == docking_location) {
				s->LeaveStation();
			}

			if (s->dest_tile == docking_location) {
				s->dest_tile = 0;
				s->current_order.Free();
			}
		}
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_STATION_DOCK]);
}

#include "table/station_land.h"

const DrawTileSprites *GetStationTileLayout(StationType st, byte gfx)
{
	return &_station_display_datas[st][gfx];
}

/**
 * Check whether a sprite is a track sprite, which can be replaced by a non-track ground sprite and a rail overlay.
 * If the ground sprite is suitable, \a ground is replaced with the new non-track ground sprite, and \a overlay_offset
 * is set to the overlay to draw.
 * @param          ti             Positional info for the tile to decide snowyness etc. May be NULL.
 * @param [in,out] ground         Groundsprite to draw.
 * @param [out]    overlay_offset Overlay to draw.
 * @return true if overlay can be drawn.
 */
bool SplitGroundSpriteForOverlay(const TileInfo *ti, SpriteID *ground, RailTrackOffset *overlay_offset)
{
	bool snow_desert;
	switch (*ground) {
		case SPR_RAIL_TRACK_X:
			snow_desert = false;
			*overlay_offset = RTO_X;
			break;

		case SPR_RAIL_TRACK_Y:
			snow_desert = false;
			*overlay_offset = RTO_Y;
			break;

		case SPR_RAIL_TRACK_X_SNOW:
			snow_desert = true;
			*overlay_offset = RTO_X;
			break;

		case SPR_RAIL_TRACK_Y_SNOW:
			snow_desert = true;
			*overlay_offset = RTO_Y;
			break;

		default:
			return false;
	}

	if (ti != NULL) {
		/* Decide snow/desert from tile */
		switch (_settings_game.game_creation.landscape) {
			case LT_ARCTIC:
				snow_desert = (uint)ti->z > GetSnowLine() * TILE_HEIGHT;
				break;

			case LT_TROPIC:
				snow_desert = GetTropicZone(ti->tile) == TROPICZONE_DESERT;
				break;

			default:
				break;
		}
	}

	*ground = snow_desert ? SPR_FLAT_SNOW_DESERT_TILE : SPR_FLAT_GRASS_TILE;
	return true;
}

static void DrawTile_Station(TileInfo *ti)
{
	const NewGRFSpriteLayout *layout = NULL;
	DrawTileSprites tmp_rail_layout;
	const DrawTileSprites *t = NULL;
	RoadTypes roadtypes;
	int32 total_offset;
	const RailtypeInfo *rti = NULL;
	uint32 relocation = 0;
	uint32 ground_relocation = 0;
	BaseStation *st = NULL;
	const StationSpec *statspec = NULL;
	uint tile_layout = 0;

	if (HasStationRail(ti->tile)) {
		rti = GetRailTypeInfo(GetRailType(ti->tile));
		roadtypes = ROADTYPES_NONE;
		total_offset = rti->GetRailtypeSpriteOffset();

		if (IsCustomStationSpecIndex(ti->tile)) {
			/* look for customization */
			st = BaseStation::GetByTile(ti->tile);
			statspec = st->speclist[GetCustomStationSpecIndex(ti->tile)].spec;

			if (statspec != NULL) {
				tile_layout = GetStationGfx(ti->tile);

				if (HasBit(statspec->callback_mask, CBM_STATION_SPRITE_LAYOUT)) {
					uint16 callback = GetStationCallback(CBID_STATION_SPRITE_LAYOUT, 0, 0, statspec, st, ti->tile);
					if (callback != CALLBACK_FAILED) tile_layout = (callback & ~1) + GetRailStationAxis(ti->tile);
				}

				/* Ensure the chosen tile layout is valid for this custom station */
				if (statspec->renderdata != NULL) {
					layout = &statspec->renderdata[tile_layout < statspec->tiles ? tile_layout : (uint)GetRailStationAxis(ti->tile)];
					if (!layout->NeedsPreprocessing()) {
						t = layout;
						layout = NULL;
					}
				}
			}
		}
	} else {
		roadtypes = IsRoadStop(ti->tile) ? GetRoadTypes(ti->tile) : ROADTYPES_NONE;
		total_offset = 0;
	}

	StationGfx gfx = GetStationGfx(ti->tile);
	if (IsAirport(ti->tile)) {
		gfx = GetAirportGfx(ti->tile);
		if (gfx >= NEW_AIRPORTTILE_OFFSET) {
			const AirportTileSpec *ats = AirportTileSpec::Get(gfx);
			if (ats->grf_prop.spritegroup[0] != NULL && DrawNewAirportTile(ti, Station::GetByTile(ti->tile), gfx, ats)) {
				return;
			}
			/* No sprite group (or no valid one) found, meaning no graphics associated.
			 * Use the substitute one instead */
			assert(ats->grf_prop.subst_id != INVALID_AIRPORTTILE);
			gfx = ats->grf_prop.subst_id;
		}
		switch (gfx) {
			case APT_RADAR_GRASS_FENCE_SW:
				t = &_station_display_datas_airport_radar_grass_fence_sw[GetAnimationFrame(ti->tile)];
				break;
			case APT_GRASS_FENCE_NE_FLAG:
				t = &_station_display_datas_airport_flag_grass_fence_ne[GetAnimationFrame(ti->tile)];
				break;
			case APT_RADAR_FENCE_SW:
				t = &_station_display_datas_airport_radar_fence_sw[GetAnimationFrame(ti->tile)];
				break;
			case APT_RADAR_FENCE_NE:
				t = &_station_display_datas_airport_radar_fence_ne[GetAnimationFrame(ti->tile)];
				break;
			case APT_GRASS_FENCE_NE_FLAG_2:
				t = &_station_display_datas_airport_flag_grass_fence_ne_2[GetAnimationFrame(ti->tile)];
				break;
		}
	}

	Owner owner = GetTileOwner(ti->tile);

	PaletteID palette;
	if (Company::IsValidID(owner)) {
		palette = COMPANY_SPRITE_COLOUR(owner);
	} else {
		/* Some stations are not owner by a company, namely oil rigs */
		palette = PALETTE_TO_GREY;
	}

	if (layout == NULL && (t == NULL || t->seq == NULL)) t = GetStationTileLayout(GetStationType(ti->tile), gfx);

	/* don't show foundation for docks */
	if (ti->tileh != SLOPE_FLAT && !IsDock(ti->tile)) {
		if (statspec != NULL && HasBit(statspec->flags, SSF_CUSTOM_FOUNDATIONS)) {
			/* Station has custom foundations.
			 * Check whether the foundation continues beyond the tile's upper sides. */
			uint edge_info = 0;
			int z;
			Slope slope = GetFoundationPixelSlope(ti->tile, &z);
			if (!HasFoundationNW(ti->tile, slope, z)) SetBit(edge_info, 0);
			if (!HasFoundationNE(ti->tile, slope, z)) SetBit(edge_info, 1);
			SpriteID image = GetCustomStationFoundationRelocation(statspec, st, ti->tile, tile_layout, edge_info);
			if (image == 0) goto draw_default_foundation;

			if (HasBit(statspec->flags, SSF_EXTENDED_FOUNDATIONS)) {
				/* Station provides extended foundations. */

				static const uint8 foundation_parts[] = {
					0, 0, 0, 0, // Invalid,  Invalid,   Invalid,   SLOPE_SW
					0, 1, 2, 3, // Invalid,  SLOPE_EW,  SLOPE_SE,  SLOPE_WSE
					0, 4, 5, 6, // Invalid,  SLOPE_NW,  SLOPE_NS,  SLOPE_NWS
					7, 8, 9     // SLOPE_NE, SLOPE_ENW, SLOPE_SEN
				};

				AddSortableSpriteToDraw(image + foundation_parts[ti->tileh], PAL_NONE, ti->x, ti->y, 16, 16, 7, ti->z);
			} else {
				/* Draw simple foundations, built up from 8 possible foundation sprites. */

				/* Each set bit represents one of the eight composite sprites to be drawn.
				 * 'Invalid' entries will not drawn but are included for completeness. */
				static const uint8 composite_foundation_parts[] = {
					/* Invalid  (00000000), Invalid   (11010001), Invalid   (11100100), SLOPE_SW  (11100000) */
					   0x00,                0xD1,                 0xE4,                 0xE0,
					/* Invalid  (11001010), SLOPE_EW  (11001001), SLOPE_SE  (11000100), SLOPE_WSE (11000000) */
					   0xCA,                0xC9,                 0xC4,                 0xC0,
					/* Invalid  (11010010), SLOPE_NW  (10010001), SLOPE_NS  (11100100), SLOPE_NWS (10100000) */
					   0xD2,                0x91,                 0xE4,                 0xA0,
					/* SLOPE_NE (01001010), SLOPE_ENW (00001001), SLOPE_SEN (01000100) */
					   0x4A,                0x09,                 0x44
				};

				uint8 parts = composite_foundation_parts[ti->tileh];

				/* If foundations continue beyond the tile's upper sides then
				 * mask out the last two pieces. */
				if (HasBit(edge_info, 0)) ClrBit(parts, 6);
				if (HasBit(edge_info, 1)) ClrBit(parts, 7);

				if (parts == 0) {
					/* We always have to draw at least one sprite to make sure there is a boundingbox and a sprite with the
					 * correct offset for the childsprites.
					 * So, draw the (completely empty) sprite of the default foundations. */
					goto draw_default_foundation;
				}

				StartSpriteCombine();
				for (int i = 0; i < 8; i++) {
					if (HasBit(parts, i)) {
						AddSortableSpriteToDraw(image + i, PAL_NONE, ti->x, ti->y, 16, 16, 7, ti->z);
					}
				}
				EndSpriteCombine();
			}

			OffsetGroundSprite(31, 1);
			ti->z += ApplyPixelFoundationToSlope(FOUNDATION_LEVELED, &ti->tileh);
		} else {
draw_default_foundation:
			DrawFoundation(ti, FOUNDATION_LEVELED);
		}
	}

	if (IsBuoy(ti->tile)) {
		DrawWaterClassGround(ti);
		SpriteID sprite = GetCanalSprite(CF_BUOY, ti->tile);
		if (sprite != 0) total_offset = sprite - SPR_IMG_BUOY;
	} else if (IsDock(ti->tile) || (IsOilRig(ti->tile) && IsTileOnWater(ti->tile))) {
		if (ti->tileh == SLOPE_FLAT) {
			DrawWaterClassGround(ti);
		} else {
			assert(IsDock(ti->tile));
			TileIndex water_tile = ti->tile + TileOffsByDiagDir(GetDockDirection(ti->tile));
			WaterClass wc = GetWaterClass(water_tile);
			if (wc == WATER_CLASS_SEA) {
				DrawShoreTile(ti->tileh);
			} else {
				DrawClearLandTile(ti, 3);
			}
		}
	} else {
		if (layout != NULL) {
			/* Sprite layout which needs preprocessing */
			bool separate_ground = HasBit(statspec->flags, SSF_SEPARATE_GROUND);
			uint32 var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, 0, separate_ground);
			uint8 var10;
			FOR_EACH_SET_BIT(var10, var10_values) {
				uint32 var10_relocation = GetCustomStationRelocation(statspec, st, ti->tile, var10);
				layout->ProcessRegisters(var10, var10_relocation, separate_ground);
			}
			tmp_rail_layout.seq = layout->GetLayout(&tmp_rail_layout.ground);
			t = &tmp_rail_layout;
			total_offset = 0;
		} else if (statspec != NULL) {
			/* Simple sprite layout */
			ground_relocation = relocation = GetCustomStationRelocation(statspec, st, ti->tile, 0);
			if (HasBit(statspec->flags, SSF_SEPARATE_GROUND)) {
				ground_relocation = GetCustomStationRelocation(statspec, st, ti->tile, 1);
			}
			ground_relocation += rti->fallback_railtype;
		}

		SpriteID image = t->ground.sprite;
		PaletteID pal  = t->ground.pal;
		RailTrackOffset overlay_offset;
		if (rti != NULL && rti->UsesOverlay() && SplitGroundSpriteForOverlay(ti, &image, &overlay_offset)) {
			SpriteID ground = GetCustomRailSprite(rti, ti->tile, RTSG_GROUND);
			DrawGroundSprite(image, PAL_NONE);
			DrawGroundSprite(ground + overlay_offset, PAL_NONE);

			if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasStationReservation(ti->tile)) {
				SpriteID overlay = GetCustomRailSprite(rti, ti->tile, RTSG_OVERLAY);
				DrawGroundSprite(overlay + overlay_offset, PALETTE_CRASH);
			}
		} else {
			image += HasBit(image, SPRITE_MODIFIER_CUSTOM_SPRITE) ? ground_relocation : total_offset;
			if (HasBit(pal, SPRITE_MODIFIER_CUSTOM_SPRITE)) pal += ground_relocation;
			DrawGroundSprite(image, GroundSpritePaletteTransform(image, pal, palette));

			/* PBS debugging, draw reserved tracks darker */
			if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasStationRail(ti->tile) && HasStationReservation(ti->tile)) {
				const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(ti->tile));
				DrawGroundSprite(GetRailStationAxis(ti->tile) == AXIS_X ? rti->base_sprites.single_x : rti->base_sprites.single_y, PALETTE_CRASH);
			}
		}
	}

	if (HasStationRail(ti->tile) && HasRailCatenaryDrawn(GetRailType(ti->tile))) DrawRailCatenary(ti);

	if (HasBit(roadtypes, ROADTYPE_TRAM)) {
		Axis axis = GetRoadStopDir(ti->tile) == DIAGDIR_NE ? AXIS_X : AXIS_Y;
		DrawGroundSprite((HasBit(roadtypes, ROADTYPE_ROAD) ? SPR_TRAMWAY_OVERLAY : SPR_TRAMWAY_TRAM) + (axis ^ 1), PAL_NONE);
		DrawRoadCatenary(ti, axis == AXIS_X ? ROAD_X : ROAD_Y);
	}

	if (IsRailWaypoint(ti->tile)) {
		/* Don't offset the waypoint graphics; they're always the same. */
		total_offset = 0;
	}

	DrawRailTileSeq(ti, t, TO_BUILDINGS, total_offset, relocation, palette);
}

void StationPickerDrawSprite(int x, int y, StationType st, RailType railtype, RoadType roadtype, int image)
{
	int32 total_offset = 0;
	PaletteID pal = COMPANY_SPRITE_COLOUR(_local_company);
	const DrawTileSprites *t = GetStationTileLayout(st, image);
	const RailtypeInfo *rti = NULL;

	if (railtype != INVALID_RAILTYPE) {
		rti = GetRailTypeInfo(railtype);
		total_offset = rti->GetRailtypeSpriteOffset();
	}

	SpriteID img = t->ground.sprite;
	RailTrackOffset overlay_offset;
	if (rti != NULL && rti->UsesOverlay() && SplitGroundSpriteForOverlay(NULL, &img, &overlay_offset)) {
		SpriteID ground = GetCustomRailSprite(rti, INVALID_TILE, RTSG_GROUND);
		DrawSprite(img, PAL_NONE, x, y);
		DrawSprite(ground + overlay_offset, PAL_NONE, x, y);
	} else {
		DrawSprite(img + total_offset, HasBit(img, PALETTE_MODIFIER_COLOUR) ? pal : PAL_NONE, x, y);
	}

	if (roadtype == ROADTYPE_TRAM) {
		DrawSprite(SPR_TRAMWAY_TRAM + (t->ground.sprite == SPR_ROAD_PAVED_STRAIGHT_X ? 1 : 0), PAL_NONE, x, y);
	}

	/* Default waypoint has no railtype specific sprites */
	DrawRailTileSeqInGUI(x, y, t, st == STATION_WAYPOINT ? 0 : total_offset, 0, pal);
}

static int GetSlopePixelZ_Station(TileIndex tile, uint x, uint y)
{
	return GetTileMaxPixelZ(tile);
}

static Foundation GetFoundation_Station(TileIndex tile, Slope tileh)
{
	return FlatteningFoundation(tileh);
}

static void GetTileDesc_Station(TileIndex tile, TileDesc *td)
{
	td->owner[0] = GetTileOwner(tile);
	if (IsDriveThroughStopTile(tile)) {
		Owner road_owner = INVALID_OWNER;
		Owner tram_owner = INVALID_OWNER;
		RoadTypes rts = GetRoadTypes(tile);
		if (HasBit(rts, ROADTYPE_ROAD)) road_owner = GetRoadOwner(tile, ROADTYPE_ROAD);
		if (HasBit(rts, ROADTYPE_TRAM)) tram_owner = GetRoadOwner(tile, ROADTYPE_TRAM);

		/* Is there a mix of owners? */
		if ((tram_owner != INVALID_OWNER && tram_owner != td->owner[0]) ||
				(road_owner != INVALID_OWNER && road_owner != td->owner[0])) {
			uint i = 1;
			if (road_owner != INVALID_OWNER) {
				td->owner_type[i] = STR_LAND_AREA_INFORMATION_ROAD_OWNER;
				td->owner[i] = road_owner;
				i++;
			}
			if (tram_owner != INVALID_OWNER) {
				td->owner_type[i] = STR_LAND_AREA_INFORMATION_TRAM_OWNER;
				td->owner[i] = tram_owner;
			}
		}
	}
	td->build_date = BaseStation::GetByTile(tile)->build_date;

	if (HasStationTileRail(tile)) {
		const StationSpec *spec = GetStationSpec(tile);

		if (spec != NULL) {
			td->station_class = StationClass::Get(spec->cls_id)->name;
			td->station_name  = spec->name;

			if (spec->grf_prop.grffile != NULL) {
				const GRFConfig *gc = GetGRFConfig(spec->grf_prop.grffile->grfid);
				td->grf = gc->GetName();
			}
		}

		const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(tile));
		td->rail_speed = rti->max_speed;
		td->railtype = rti->strings.name;
	}

	if (IsAirport(tile)) {
		const AirportSpec *as = Station::GetByTile(tile)->airport.GetSpec();
		td->airport_class = AirportClass::Get(as->cls_id)->name;
		td->airport_name = as->name;

		const AirportTileSpec *ats = AirportTileSpec::GetByTile(tile);
		td->airport_tile_name = ats->name;

		if (as->grf_prop.grffile != NULL) {
			const GRFConfig *gc = GetGRFConfig(as->grf_prop.grffile->grfid);
			td->grf = gc->GetName();
		} else if (ats->grf_prop.grffile != NULL) {
			const GRFConfig *gc = GetGRFConfig(ats->grf_prop.grffile->grfid);
			td->grf = gc->GetName();
		}
	}

	StringID str;
	switch (GetStationType(tile)) {
		default: NOT_REACHED();
		case STATION_RAIL:     str = STR_LAI_STATION_DESCRIPTION_RAILROAD_STATION; break;
		case STATION_AIRPORT:
			str = (IsHangar(tile) ? STR_LAI_STATION_DESCRIPTION_AIRCRAFT_HANGAR : STR_LAI_STATION_DESCRIPTION_AIRPORT);
			break;
		case STATION_TRUCK:    str = STR_LAI_STATION_DESCRIPTION_TRUCK_LOADING_AREA; break;
		case STATION_BUS:      str = STR_LAI_STATION_DESCRIPTION_BUS_STATION; break;
		case STATION_OILRIG:   str = STR_INDUSTRY_NAME_OIL_RIG; break;
		case STATION_DOCK:     str = STR_LAI_STATION_DESCRIPTION_SHIP_DOCK; break;
		case STATION_BUOY:     str = STR_LAI_STATION_DESCRIPTION_BUOY; break;
		case STATION_WAYPOINT: str = STR_LAI_STATION_DESCRIPTION_WAYPOINT; break;
	}
	td->str = str;
}


static TrackStatus GetTileTrackStatus_Station(TileIndex tile, TransportType mode, uint sub_mode, DiagDirection side)
{
	TrackBits trackbits = TRACK_BIT_NONE;

	switch (mode) {
		case TRANSPORT_RAIL:
			if (HasStationRail(tile) && !IsStationTileBlocked(tile)) {
				trackbits = TrackToTrackBits(GetRailStationTrack(tile));
			}
			break;

		case TRANSPORT_WATER:
			/* buoy is coded as a station, it is always on open water */
			if (IsBuoy(tile)) {
				trackbits = TRACK_BIT_ALL;
				/* remove tracks that connect NE map edge */
				if (TileX(tile) == 0) trackbits &= ~(TRACK_BIT_X | TRACK_BIT_UPPER | TRACK_BIT_RIGHT);
				/* remove tracks that connect NW map edge */
				if (TileY(tile) == 0) trackbits &= ~(TRACK_BIT_Y | TRACK_BIT_LEFT | TRACK_BIT_UPPER);
			}
			break;

		case TRANSPORT_ROAD:
			if ((GetRoadTypes(tile) & sub_mode) != 0 && IsRoadStop(tile)) {
				DiagDirection dir = GetRoadStopDir(tile);
				Axis axis = DiagDirToAxis(dir);

				if (side != INVALID_DIAGDIR) {
					if (axis != DiagDirToAxis(side) || (IsStandardRoadStopTile(tile) && dir != side)) break;
				}

				trackbits = AxisToTrackBits(axis);
			}
			break;

		default:
			break;
	}

	return CombineTrackStatus(TrackBitsToTrackdirBits(trackbits), TRACKDIR_BIT_NONE);
}


static void TileLoop_Station(TileIndex tile)
{
	/* FIXME -- GetTileTrackStatus_Station -> animated stationtiles
	 * hardcoded.....not good */
	switch (GetStationType(tile)) {
		case STATION_AIRPORT:
			AirportTileAnimationTrigger(Station::GetByTile(tile), tile, AAT_TILELOOP);
			break;

		case STATION_DOCK:
			if (!IsTileFlat(tile)) break; // only handle water part
			FALLTHROUGH;

		case STATION_OILRIG: //(station part)
		case STATION_BUOY:
			TileLoop_Water(tile);
			break;

		default: break;
	}
}


static void AnimateTile_Station(TileIndex tile)
{
	if (HasStationRail(tile)) {
		AnimateStationTile(tile);
		return;
	}

	if (IsAirport(tile)) {
		AnimateAirportTile(tile);
	}
}


static bool ClickTile_Station(TileIndex tile)
{
	const BaseStation *bst = BaseStation::GetByTile(tile);

	if (bst->facilities & FACIL_WAYPOINT) {
		ShowWaypointWindow(Waypoint::From(bst));
	} else if (IsHangar(tile)) {
		const Station *st = Station::From(bst);
		ShowDepotWindow(st->airport.GetHangarTile(st->airport.GetHangarNum(tile)), VEH_AIRCRAFT);
	} else {
		ShowStationViewWindow(bst->index);
	}
	return true;
}

static VehicleEnterTileStatus VehicleEnter_Station(Vehicle *v, TileIndex tile, int x, int y)
{
	if (v->type == VEH_TRAIN) {
		StationID station_id = GetStationIndex(tile);
		if (!v->current_order.ShouldStopAtStation(v, station_id)) return VETSB_CONTINUE;
		if (!IsRailStation(tile) || !v->IsFrontEngine()) return VETSB_CONTINUE;

		int station_ahead;
		int station_length;
		int stop = GetTrainStopLocation(station_id, tile, Train::From(v), &station_ahead, &station_length);

		/* Stop whenever that amount of station ahead + the distance from the
		 * begin of the platform to the stop location is longer than the length
		 * of the platform. Station ahead 'includes' the current tile where the
		 * vehicle is on, so we need to subtract that. */
		if (stop + station_ahead - (int)TILE_SIZE >= station_length) return VETSB_CONTINUE;

		DiagDirection dir = DirToDiagDir(v->direction);

		x &= 0xF;
		y &= 0xF;

		if (DiagDirToAxis(dir) != AXIS_X) Swap(x, y);
		if (y == TILE_SIZE / 2) {
			if (dir != DIAGDIR_SE && dir != DIAGDIR_SW) x = TILE_SIZE - 1 - x;
			stop &= TILE_SIZE - 1;

			if (x == stop) {
				return VETSB_ENTERED_STATION | (VehicleEnterTileStatus)(station_id << VETS_STATION_ID_OFFSET); // enter station
			} else if (x < stop) {
				v->vehstatus |= VS_TRAIN_SLOWING;
				uint16 spd = max(0, (stop - x) * 20 - 15);
				if (spd < v->cur_speed) v->cur_speed = spd;
			}
		}
	} else if (v->type == VEH_ROAD) {
		RoadVehicle *rv = RoadVehicle::From(v);
		if (rv->state < RVSB_IN_ROAD_STOP && !IsReversingRoadTrackdir((Trackdir)rv->state) && rv->frame == 0) {
			if (IsRoadStop(tile) && rv->IsFrontEngine()) {
				/* Attempt to allocate a parking bay in a road stop */
				return RoadStop::GetByTile(tile, GetRoadStopType(tile))->Enter(rv) ? VETSB_CONTINUE : VETSB_CANNOT_ENTER;
			}
		}
	}

	return VETSB_CONTINUE;
}

/**
 * Run the watched cargo callback for all houses in the catchment area.
 * @param st Station.
 */
void TriggerWatchedCargoCallbacks(Station *st)
{
	/* Collect cargoes accepted since the last big tick. */
	uint cargoes = 0;
	for (CargoID cid = 0; cid < NUM_CARGO; cid++) {
		if (HasBit(st->goods[cid].status, GoodsEntry::GES_ACCEPTED_BIGTICK)) SetBit(cargoes, cid);
	}

	/* Anything to do? */
	if (cargoes == 0) return;

	/* Loop over all houses in the catchment. */
	Rect r = st->GetCatchmentRect();
	TileArea ta(TileXY(r.left, r.top), TileXY(r.right, r.bottom));
	TILE_AREA_LOOP(tile, ta) {
		if (IsTileType(tile, MP_HOUSE)) {
			WatchedCargoCallback(tile, cargoes);
		}
	}
}

/**
 * This function is called for each station once every 250 ticks.
 * Not all stations will get the tick at the same time.
 * @param st the station receiving the tick.
 * @return true if the station is still valid (wasn't deleted)
 */
static bool StationHandleBigTick(BaseStation *st)
{
	if (!st->IsInUse()) {
		if (++st->delete_ctr >= 8) delete st;
		return false;
	}

	if (Station::IsExpected(st)) {
		TriggerWatchedCargoCallbacks(Station::From(st));

		for (CargoID i = 0; i < NUM_CARGO; i++) {
			ClrBit(Station::From(st)->goods[i].status, GoodsEntry::GES_ACCEPTED_BIGTICK);
		}
	}


	if ((st->facilities & FACIL_WAYPOINT) == 0) UpdateStationAcceptance(Station::From(st), true);

	return true;
}

static inline void byte_inc_sat(byte *p)
{
	byte b = *p + 1;
	if (b != 0) *p = b;
}

/**
 * Truncate the cargo by a specific amount.
 * @param cs The type of cargo to perform the truncation for.
 * @param ge The goods entry, of the station, to truncate.
 * @param amount The amount to truncate the cargo by.
 */
static void TruncateCargo(const CargoSpec *cs, GoodsEntry *ge, uint amount = UINT_MAX)
{
	/* If truncating also punish the source stations' ratings to
	 * decrease the flow of incoming cargo. */

	StationCargoAmountMap waiting_per_source;
	ge->cargo.Truncate(amount, &waiting_per_source);
	for (StationCargoAmountMap::iterator i(waiting_per_source.begin()); i != waiting_per_source.end(); ++i) {
		Station *source_station = Station::GetIfValid(i->first);
		if (source_station == NULL) continue;

		GoodsEntry &source_ge = source_station->goods[cs->Index()];
		source_ge.max_waiting_cargo = max(source_ge.max_waiting_cargo, i->second);
	}
}

static void UpdateStationRating(Station *st)
{
	bool waiting_changed = false;

	byte_inc_sat(&st->time_since_load);
	byte_inc_sat(&st->time_since_unload);

	const CargoSpec *cs;
	FOR_ALL_CARGOSPECS(cs) {
		GoodsEntry *ge = &st->goods[cs->Index()];
		/* Slowly increase the rating back to his original level in the case we
		 *  didn't deliver cargo yet to this station. This happens when a bribe
		 *  failed while you didn't moved that cargo yet to a station. */
		if (!ge->HasRating() && ge->rating < INITIAL_STATION_RATING) {
			ge->rating++;
		}

		/* Only change the rating if we are moving this cargo */
		if (ge->HasRating()) {
			byte_inc_sat(&ge->time_since_pickup);
			if (ge->time_since_pickup == 255 && _settings_game.order.selectgoods) {
				ClrBit(ge->status, GoodsEntry::GES_RATING);
				ge->last_speed = 0;
				TruncateCargo(cs, ge);
				waiting_changed = true;
				continue;
			}

			bool skip = false;
			int rating = 0;
			uint waiting = ge->cargo.AvailableCount();

			/* num_dests is at least 1 if there is any cargo as
			 * INVALID_STATION is also a destination.
			 */
			uint num_dests = (uint)ge->cargo.Packets()->MapSize();

			/* Average amount of cargo per next hop, but prefer solitary stations
			 * with only one or two next hops. They are allowed to have more
			 * cargo waiting per next hop.
			 * With manual cargo distribution waiting_avg = waiting / 2 as then
			 * INVALID_STATION is the only destination.
			 */
			uint waiting_avg = waiting / (num_dests + 1);

			if (HasBit(cs->callback_mask, CBM_CARGO_STATION_RATING_CALC)) {
				/* Perform custom station rating. If it succeeds the speed, days in transit and
				 * waiting cargo ratings must not be executed. */

				/* NewGRFs expect last speed to be 0xFF when no vehicle has arrived yet. */
				uint last_speed = ge->HasVehicleEverTriedLoading() ? ge->last_speed : 0xFF;

				uint32 var18 = min(ge->time_since_pickup, 0xFF) | (min(ge->max_waiting_cargo, 0xFFFF) << 8) | (min(last_speed, 0xFF) << 24);
				/* Convert to the 'old' vehicle types */
				uint32 var10 = (st->last_vehicle_type == VEH_INVALID) ? 0x0 : (st->last_vehicle_type + 0x10);
				uint16 callback = GetCargoCallback(CBID_CARGO_STATION_RATING_CALC, var10, var18, cs);
				if (callback != CALLBACK_FAILED) {
					skip = true;
					rating = GB(callback, 0, 14);

					/* Simulate a 15 bit signed value */
					if (HasBit(callback, 14)) rating -= 0x4000;
				}
			}

			if (!skip) {
				int b = ge->last_speed - 85;
				if (b >= 0) rating += b >> 2;

				byte waittime = ge->time_since_pickup;
				if (st->last_vehicle_type == VEH_SHIP) waittime >>= 2;
				(waittime > 21) ||
				(rating += 25, waittime > 12) ||
				(rating += 25, waittime > 6) ||
				(rating += 45, waittime > 3) ||
				(rating += 35, true);

				(rating -= 90, ge->max_waiting_cargo > 1500) ||
				(rating += 55, ge->max_waiting_cargo > 1000) ||
				(rating += 35, ge->max_waiting_cargo > 600) ||
				(rating += 10, ge->max_waiting_cargo > 300) ||
				(rating += 20, ge->max_waiting_cargo > 100) ||
				(rating += 10, true);
			}

			if (Company::IsValidID(st->owner) && HasBit(st->town->statues, st->owner)) rating += 26;

			byte age = ge->last_age;
			(age >= 3) ||
			(rating += 10, age >= 2) ||
			(rating += 10, age >= 1) ||
			(rating += 13, true);

			{
				int or_ = ge->rating; // old rating

				/* only modify rating in steps of -2, -1, 0, 1 or 2 */
				ge->rating = rating = or_ + Clamp(Clamp(rating, 0, 255) - or_, -2, 2);

				/* if rating is <= 64 and more than 100 items waiting on average per destination,
				 * remove some random amount of goods from the station */
				if (rating <= 64 && waiting_avg >= 100) {
					int dec = Random() & 0x1F;
					if (waiting_avg < 200) dec &= 7;
					waiting -= (dec + 1) * num_dests;
					waiting_changed = true;
				}

				/* if rating is <= 127 and there are any items waiting, maybe remove some goods. */
				if (rating <= 127 && waiting != 0) {
					uint32 r = Random();
					if (rating <= (int)GB(r, 0, 7)) {
						/* Need to have int, otherwise it will just overflow etc. */
						waiting = max((int)waiting - (int)((GB(r, 8, 2) - 1) * num_dests), 0);
						waiting_changed = true;
					}
				}

				/* At some point we really must cap the cargo. Previously this
				 * was a strict 4095, but now we'll have a less strict, but
				 * increasingly aggressive truncation of the amount of cargo. */
				static const uint WAITING_CARGO_THRESHOLD  = 1 << 12;
				static const uint WAITING_CARGO_CUT_FACTOR = 1 <<  6;
				static const uint MAX_WAITING_CARGO        = 1 << 15;

				if (waiting > WAITING_CARGO_THRESHOLD) {
					uint difference = waiting - WAITING_CARGO_THRESHOLD;
					waiting -= (difference / WAITING_CARGO_CUT_FACTOR);

					waiting = min(waiting, MAX_WAITING_CARGO);
					waiting_changed = true;
				}

				/* We can't truncate cargo that's already reserved for loading.
				 * Thus StoredCount() here. */
				if (waiting_changed && waiting < ge->cargo.AvailableCount()) {
					/* Feed back the exact own waiting cargo at this station for the
					 * next rating calculation. */
					ge->max_waiting_cargo = 0;

					TruncateCargo(cs, ge, ge->cargo.AvailableCount() - waiting);
				} else {
					/* If the average number per next hop is low, be more forgiving. */
					ge->max_waiting_cargo = waiting_avg;
				}
			}
		}
	}

	StationID index = st->index;
	if (waiting_changed) {
		SetWindowDirty(WC_STATION_VIEW, index); // update whole window
	} else {
		SetWindowWidgetDirty(WC_STATION_VIEW, index, WID_SV_ACCEPT_RATING_LIST); // update only ratings list
	}
}

/**
 * Reroute cargo of type c at station st or in any vehicles unloading there.
 * Make sure the cargo's new next hop is neither "avoid" nor "avoid2".
 * @param st Station to be rerouted at.
 * @param c Type of cargo.
 * @param avoid Original next hop of cargo, avoid this.
 * @param avoid2 Another station to be avoided when rerouting.
 */
void RerouteCargo(Station *st, CargoID c, StationID avoid, StationID avoid2)
{
	GoodsEntry &ge = st->goods[c];

	/* Reroute cargo in station. */
	ge.cargo.Reroute(UINT_MAX, &ge.cargo, avoid, avoid2, &ge);

	/* Reroute cargo staged to be transfered. */
	for (std::list<Vehicle *>::iterator it(st->loading_vehicles.begin()); it != st->loading_vehicles.end(); ++it) {
		for (Vehicle *v = *it; v != NULL; v = v->Next()) {
			if (v->cargo_type != c) continue;
			v->cargo.Reroute(UINT_MAX, &v->cargo, avoid, avoid2, &ge);
		}
	}
}

/**
 * Check all next hops of cargo packets in this station for existance of a
 * a valid link they may use to travel on. Reroute any cargo not having a valid
 * link and remove timed out links found like this from the linkgraph. We're
 * not all links here as that is expensive and useless. A link no one is using
 * doesn't hurt either.
 * @param from Station to check.
 */
void DeleteStaleLinks(Station *from)
{
	for (CargoID c = 0; c < NUM_CARGO; ++c) {
		const bool auto_distributed = (_settings_game.linkgraph.GetDistributionType(c) != DT_MANUAL);
		GoodsEntry &ge = from->goods[c];
		LinkGraph *lg = LinkGraph::GetIfValid(ge.link_graph);
		if (lg == NULL) continue;
		Node node = (*lg)[ge.node];
		for (EdgeIterator it(node.Begin()); it != node.End();) {
			Edge edge = it->second;
			Station *to = Station::Get((*lg)[it->first].Station());
			assert(to->goods[c].node == it->first);
			++it; // Do that before removing the edge. Anything else may crash.
			assert(_date >= edge.LastUpdate());
			uint timeout = LinkGraph::MIN_TIMEOUT_DISTANCE + (DistanceManhattan(from->xy, to->xy) >> 3);
			if ((uint)(_date - edge.LastUpdate()) > timeout) {
				bool updated = false;

				if (auto_distributed) {
					/* Have all vehicles refresh their next hops before deciding to
					 * remove the node. */
					OrderList *l;
					SmallVector<Vehicle *, 32> vehicles;
					FOR_ALL_ORDER_LISTS(l) {
						bool found_from = false;
						bool found_to = false;
						for (Order *order = l->GetFirstOrder(); order != NULL; order = order->next) {
							if (!order->IsType(OT_GOTO_STATION) && !order->IsType(OT_IMPLICIT)) continue;
							if (order->GetDestination() == from->index) {
								found_from = true;
								if (found_to) break;
							} else if (order->GetDestination() == to->index) {
								found_to = true;
								if (found_from) break;
							}
						}
						if (!found_to || !found_from) continue;
						*(vehicles.Append()) = l->GetFirstSharedVehicle();
					}

					Vehicle **iter = vehicles.Begin();
					while (iter != vehicles.End()) {
						Vehicle *v = *iter;

						LinkRefresher::Run(v, false); // Don't allow merging. Otherwise lg might get deleted.
						if (edge.LastUpdate() == _date) {
							updated = true;
							break;
						}

						Vehicle *next_shared = v->NextShared();
						if (next_shared) {
							*iter = next_shared;
							++iter;
						} else {
							vehicles.Erase(iter);
						}

						if (iter == vehicles.End()) iter = vehicles.Begin();
					}
				}

				if (!updated) {
					/* If it's still considered dead remove it. */
					node.RemoveEdge(to->goods[c].node);
					ge.flows.DeleteFlows(to->index);
					RerouteCargo(from, c, to->index, from->index);
				}
			} else if (edge.LastUnrestrictedUpdate() != INVALID_DATE && (uint)(_date - edge.LastUnrestrictedUpdate()) > timeout) {
				edge.Restrict();
				ge.flows.RestrictFlows(to->index);
				RerouteCargo(from, c, to->index, from->index);
			} else if (edge.LastRestrictedUpdate() != INVALID_DATE && (uint)(_date - edge.LastRestrictedUpdate()) > timeout) {
				edge.Release();
			}
		}
		assert(_date >= lg->LastCompression());
		if ((uint)(_date - lg->LastCompression()) > LinkGraph::COMPRESSION_INTERVAL) {
			lg->Compress();
		}
	}
}

/**
 * Increase capacity for a link stat given by station cargo and next hop.
 * @param st Station to get the link stats from.
 * @param cargo Cargo to increase stat for.
 * @param next_station_id Station the consist will be travelling to next.
 * @param capacity Capacity to add to link stat.
 * @param usage Usage to add to link stat.
 * @param mode Update mode to be applied.
 */
void IncreaseStats(Station *st, CargoID cargo, StationID next_station_id, uint capacity, uint usage, EdgeUpdateMode mode)
{
	GoodsEntry &ge1 = st->goods[cargo];
	Station *st2 = Station::Get(next_station_id);
	GoodsEntry &ge2 = st2->goods[cargo];
	LinkGraph *lg = NULL;
	if (ge1.link_graph == INVALID_LINK_GRAPH) {
		if (ge2.link_graph == INVALID_LINK_GRAPH) {
			if (LinkGraph::CanAllocateItem()) {
				lg = new LinkGraph(cargo);
				LinkGraphSchedule::instance.Queue(lg);
				ge2.link_graph = lg->index;
				ge2.node = lg->AddNode(st2);
			} else {
				DEBUG(misc, 0, "Can't allocate link graph");
			}
		} else {
			lg = LinkGraph::Get(ge2.link_graph);
		}
		if (lg) {
			ge1.link_graph = lg->index;
			ge1.node = lg->AddNode(st);
		}
	} else if (ge2.link_graph == INVALID_LINK_GRAPH) {
		lg = LinkGraph::Get(ge1.link_graph);
		ge2.link_graph = lg->index;
		ge2.node = lg->AddNode(st2);
	} else {
		lg = LinkGraph::Get(ge1.link_graph);
		if (ge1.link_graph != ge2.link_graph) {
			LinkGraph *lg2 = LinkGraph::Get(ge2.link_graph);
			if (lg->Size() < lg2->Size()) {
				LinkGraphSchedule::instance.Unqueue(lg);
				lg2->Merge(lg); // Updates GoodsEntries of lg
				lg = lg2;
			} else {
				LinkGraphSchedule::instance.Unqueue(lg2);
				lg->Merge(lg2); // Updates GoodsEntries of lg2
			}
		}
	}
	if (lg != NULL) {
		(*lg)[ge1.node].UpdateEdge(ge2.node, capacity, usage, mode);
	}
}

/**
 * Increase capacity for all link stats associated with vehicles in the given consist.
 * @param st Station to get the link stats from.
 * @param front First vehicle in the consist.
 * @param next_station_id Station the consist will be travelling to next.
 */
void IncreaseStats(Station *st, const Vehicle *front, StationID next_station_id)
{
	for (const Vehicle *v = front; v != NULL; v = v->Next()) {
		if (v->refit_cap > 0) {
			/* The cargo count can indeed be higher than the refit_cap if
			 * wagons have been auto-replaced and subsequently auto-
			 * refitted to a higher capacity. The cargo gets redistributed
			 * among the wagons in that case.
			 * As usage is not such an important figure anyway we just
			 * ignore the additional cargo then.*/
			IncreaseStats(st, v->cargo_type, next_station_id, v->refit_cap,
				min(v->refit_cap, v->cargo.StoredCount()), EUM_INCREASE);
		}
	}
}

/* called for every station each tick */
static void StationHandleSmallTick(BaseStation *st)
{
	if ((st->facilities & FACIL_WAYPOINT) != 0 || !st->IsInUse()) return;

	byte b = st->delete_ctr + 1;
	if (b >= STATION_RATING_TICKS) b = 0;
	st->delete_ctr = b;

	if (b == 0) UpdateStationRating(Station::From(st));
}

void OnTick_Station()
{
	if (_game_mode == GM_EDITOR) return;

	BaseStation *st;
	FOR_ALL_BASE_STATIONS(st) {
		StationHandleSmallTick(st);

		/* Clean up the link graph about once a week. */
		if (Station::IsExpected(st) && (_tick_counter + st->index) % STATION_LINKGRAPH_TICKS == 0) {
			DeleteStaleLinks(Station::From(st));
		};

		/* Run STATION_ACCEPTANCE_TICKS = 250 tick interval trigger for station animation.
		 * Station index is included so that triggers are not all done
		 * at the same time. */
		if ((_tick_counter + st->index) % STATION_ACCEPTANCE_TICKS == 0) {
			/* Stop processing this station if it was deleted */
			if (!StationHandleBigTick(st)) continue;
			TriggerStationAnimation(st, st->xy, SAT_250_TICKS);
			if (Station::IsExpected(st)) AirportAnimationTrigger(Station::From(st), AAT_STATION_250_TICKS);
		}
	}
}

/** Monthly loop for stations. */
void StationMonthlyLoop()
{
	Station *st;

	FOR_ALL_STATIONS(st) {
		for (CargoID i = 0; i < NUM_CARGO; i++) {
			GoodsEntry *ge = &st->goods[i];
			SB(ge->status, GoodsEntry::GES_LAST_MONTH, 1, GB(ge->status, GoodsEntry::GES_CURRENT_MONTH, 1));
			ClrBit(ge->status, GoodsEntry::GES_CURRENT_MONTH);
		}
	}
}


void ModifyStationRatingAround(TileIndex tile, Owner owner, int amount, uint radius)
{
	Station *st;

	FOR_ALL_STATIONS(st) {
		if (st->owner == owner &&
				DistanceManhattan(tile, st->xy) <= radius) {
			for (CargoID i = 0; i < NUM_CARGO; i++) {
				GoodsEntry *ge = &st->goods[i];

				if (ge->status != 0) {
					ge->rating = Clamp(ge->rating + amount, 0, 255);
				}
			}
		}
	}
}

static uint UpdateStationWaiting(Station *st, CargoID type, uint amount, SourceType source_type, SourceID source_id)
{
	/* We can't allocate a CargoPacket? Then don't do anything
	 * at all; i.e. just discard the incoming cargo. */
	if (!CargoPacket::CanAllocateItem()) return 0;

	GoodsEntry &ge = st->goods[type];
	amount += ge.amount_fract;
	ge.amount_fract = GB(amount, 0, 8);

	amount >>= 8;
	/* No new "real" cargo item yet. */
	if (amount == 0) return 0;

	StationID next = ge.GetVia(st->index);
	ge.cargo.Append(new CargoPacket(st->index, st->xy, amount, source_type, source_id), next);
	LinkGraph *lg = NULL;
	if (ge.link_graph == INVALID_LINK_GRAPH) {
		if (LinkGraph::CanAllocateItem()) {
			lg = new LinkGraph(type);
			LinkGraphSchedule::instance.Queue(lg);
			ge.link_graph = lg->index;
			ge.node = lg->AddNode(st);
		} else {
			DEBUG(misc, 0, "Can't allocate link graph");
		}
	} else {
		lg = LinkGraph::Get(ge.link_graph);
	}
	if (lg != NULL) (*lg)[ge.node].UpdateSupply(amount);

	if (!ge.HasRating()) {
		InvalidateWindowData(WC_STATION_LIST, st->index);
		SetBit(ge.status, GoodsEntry::GES_RATING);
	}

	TriggerStationRandomisation(st, st->xy, SRT_NEW_CARGO, type);
	TriggerStationAnimation(st, st->xy, SAT_NEW_CARGO, type);
	AirportAnimationTrigger(st, AAT_STATION_NEW_CARGO, type);

	SetWindowDirty(WC_STATION_VIEW, st->index);
	st->MarkTilesDirty(true);
	return amount;
}

static bool IsUniqueStationName(const char *name)
{
	const Station *st;

	FOR_ALL_STATIONS(st) {
		if (st->name != NULL && strcmp(st->name, name) == 0) return false;
	}

	return true;
}

/**
 * Rename a station
 * @param tile unused
 * @param flags operation to perform
 * @param p1 station ID that is to be renamed
 * @param p2 unused
 * @param text the new name or an empty string when resetting to the default
 * @return the cost of this operation or an error
 */
CommandCost CmdRenameStation(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	Station *st = Station::GetIfValid(p1);
	if (st == NULL) return CMD_ERROR;

	CommandCost ret = CheckOwnership(st->owner);
	if (ret.Failed()) return ret;

	bool reset = StrEmpty(text);

	if (!reset) {
		if (Utf8StringLength(text) >= MAX_LENGTH_STATION_NAME_CHARS) return CMD_ERROR;
		if (!IsUniqueStationName(text)) return_cmd_error(STR_ERROR_NAME_MUST_BE_UNIQUE);
	}

	if (flags & DC_EXEC) {
		free(st->name);
		st->name = reset ? NULL : stredup(text);

		st->UpdateVirtCoord();
		InvalidateWindowData(WC_STATION_LIST, st->owner, 1);
	}

	return CommandCost();
}

/**
 * Find all stations around a rectangular producer (industry, house, headquarter, ...)
 *
 * @param location The location/area of the producer
 * @param stations The list to store the stations in
 */
void FindStationsAroundTiles(const TileArea &location, StationList *stations)
{
	/* area to search = producer plus station catchment radius */
	uint max_rad = (_settings_game.station.modified_catchment ? MAX_CATCHMENT : CA_UNMODIFIED);

	uint x = TileX(location.tile);
	uint y = TileY(location.tile);

	uint min_x = (x > max_rad) ? x - max_rad : 0;
	uint max_x = x + location.w + max_rad;
	uint min_y = (y > max_rad) ? y - max_rad : 0;
	uint max_y = y + location.h + max_rad;

	if (min_x == 0 && _settings_game.construction.freeform_edges) min_x = 1;
	if (min_y == 0 && _settings_game.construction.freeform_edges) min_y = 1;
	if (max_x >= MapSizeX()) max_x = MapSizeX() - 1;
	if (max_y >= MapSizeY()) max_y = MapSizeY() - 1;

	for (uint cy = min_y; cy < max_y; cy++) {
		for (uint cx = min_x; cx < max_x; cx++) {
			TileIndex cur_tile = TileXY(cx, cy);
			if (!IsTileType(cur_tile, MP_STATION)) continue;

			Station *st = Station::GetByTile(cur_tile);
			/* st can be NULL in case of waypoints */
			if (st == NULL) continue;

			if (_settings_game.station.modified_catchment) {
				int rad = st->GetCatchmentRadius();
				int rad_x = cx - x;
				int rad_y = cy - y;

				if (rad_x < -rad || rad_x >= rad + location.w) continue;
				if (rad_y < -rad || rad_y >= rad + location.h) continue;
			}

			/* Insert the station in the set. This will fail if it has
			 * already been added.
			 */
			stations->Include(st);
		}
	}
}

/**
 * Run a tile loop to find stations around a tile, on demand. Cache the result for further requests
 * @return pointer to a StationList containing all stations found
 */
const StationList *StationFinder::GetStations()
{
	if (this->tile != INVALID_TILE) {
		FindStationsAroundTiles(*this, &this->stations);
		this->tile = INVALID_TILE;
	}
	return &this->stations;
}

uint MoveGoodsToStation(CargoID type, uint amount, SourceType source_type, SourceID source_id, const StationList *all_stations)
{
	/* Return if nothing to do. Also the rounding below fails for 0. */
	if (amount == 0) return 0;

	Station *st1 = NULL;   // Station with best rating
	Station *st2 = NULL;   // Second best station
	uint best_rating1 = 0; // rating of st1
	uint best_rating2 = 0; // rating of st2

	for (Station * const *st_iter = all_stations->Begin(); st_iter != all_stations->End(); ++st_iter) {
		Station *st = *st_iter;

		/* Is the station reserved exclusively for somebody else? */
		if (st->town->exclusive_counter > 0 && st->town->exclusivity != st->owner) continue;

		if (st->goods[type].rating == 0) continue; // Lowest possible rating, better not to give cargo anymore

		if (_settings_game.order.selectgoods && !st->goods[type].HasVehicleEverTriedLoading()) continue; // Selectively servicing stations, and not this one

		if (IsCargoInClass(type, CC_PASSENGERS)) {
			if (st->facilities == FACIL_TRUCK_STOP) continue; // passengers are never served by just a truck stop
		} else {
			if (st->facilities == FACIL_BUS_STOP) continue; // non-passengers are never served by just a bus stop
		}

		/* This station can be used, add it to st1/st2 */
		if (st1 == NULL || st->goods[type].rating >= best_rating1) {
			st2 = st1; best_rating2 = best_rating1; st1 = st; best_rating1 = st->goods[type].rating;
		} else if (st2 == NULL || st->goods[type].rating >= best_rating2) {
			st2 = st; best_rating2 = st->goods[type].rating;
		}
	}

	/* no stations around at all? */
	if (st1 == NULL) return 0;

	/* From now we'll calculate with fractal cargo amounts.
	 * First determine how much cargo we really have. */
	amount *= best_rating1 + 1;

	if (st2 == NULL) {
		/* only one station around */
		return UpdateStationWaiting(st1, type, amount, source_type, source_id);
	}

	/* several stations around, the best two (highest rating) are in st1 and st2 */
	assert(st1 != NULL);
	assert(st2 != NULL);
	assert(best_rating1 != 0 || best_rating2 != 0);

	/* Then determine the amount the worst station gets. We do it this way as the
	 * best should get a bonus, which in this case is the rounding difference from
	 * this calculation. In reality that will mean the bonus will be pretty low.
	 * Nevertheless, the best station should always get the most cargo regardless
	 * of rounding issues. */
	uint worst_cargo = amount * best_rating2 / (best_rating1 + best_rating2);
	assert(worst_cargo <= (amount - worst_cargo));

	/* And then send the cargo to the stations! */
	uint moved = UpdateStationWaiting(st1, type, amount - worst_cargo, source_type, source_id);
	/* These two UpdateStationWaiting's can't be in the statement as then the order
	 * of execution would be undefined and that could cause desyncs with callbacks. */
	return moved + UpdateStationWaiting(st2, type, worst_cargo, source_type, source_id);
}

void BuildOilRig(TileIndex tile)
{
	if (!Station::CanAllocateItem()) {
		DEBUG(misc, 0, "Can't allocate station for oilrig at 0x%X, reverting to oilrig only", tile);
		return;
	}

	Station *st = new Station(tile);
	st->town = ClosestTownFromTile(tile, UINT_MAX);

	st->string_id = GenerateStationName(st, tile, STATIONNAMING_OILRIG);

	assert(IsTileType(tile, MP_INDUSTRY));
	DeleteAnimatedTile(tile);
	MakeOilrig(tile, st->index, GetWaterClass(tile));

	st->owner = OWNER_NONE;
	st->airport.type = AT_OILRIG;
	st->airport.Add(tile);
	st->dock_tile = tile;
	st->facilities = FACIL_AIRPORT | FACIL_DOCK;
	st->build_date = _date;

	st->rect.BeforeAddTile(tile, StationRect::ADD_FORCE);

	st->UpdateVirtCoord();
	UpdateStationAcceptance(st, false);
	st->RecomputeIndustriesNear();
}

void DeleteOilRig(TileIndex tile)
{
	Station *st = Station::GetByTile(tile);

	MakeWaterKeepingClass(tile, OWNER_NONE);

	st->dock_tile = INVALID_TILE;
	st->airport.Clear();
	st->facilities &= ~(FACIL_AIRPORT | FACIL_DOCK);
	st->airport.flags = 0;

	st->rect.AfterRemoveTile(st, tile);

	st->UpdateVirtCoord();
	st->RecomputeIndustriesNear();
	if (!st->IsInUse()) delete st;
}

static void ChangeTileOwner_Station(TileIndex tile, Owner old_owner, Owner new_owner)
{
	if (IsRoadStopTile(tile)) {
		for (RoadType rt = ROADTYPE_ROAD; rt < ROADTYPE_END; rt++) {
			/* Update all roadtypes, no matter if they are present */
			if (GetRoadOwner(tile, rt) == old_owner) {
				if (HasTileRoadType(tile, rt)) {
					/* A drive-through road-stop has always two road bits. No need to dirty windows here, we'll redraw the whole screen anyway. */
					Company::Get(old_owner)->infrastructure.road[rt] -= 2;
					if (new_owner != INVALID_OWNER) Company::Get(new_owner)->infrastructure.road[rt] += 2;
				}
				SetRoadOwner(tile, rt, new_owner == INVALID_OWNER ? OWNER_NONE : new_owner);
			}
		}
	}

	if (!IsTileOwner(tile, old_owner)) return;

	if (new_owner != INVALID_OWNER) {
		/* Update company infrastructure counts. Only do it here
		 * if the new owner is valid as otherwise the clear
		 * command will do it for us. No need to dirty windows
		 * here, we'll redraw the whole screen anyway.*/
		Company *old_company = Company::Get(old_owner);
		Company *new_company = Company::Get(new_owner);

		/* Update counts for underlying infrastructure. */
		switch (GetStationType(tile)) {
			case STATION_RAIL:
			case STATION_WAYPOINT:
				if (!IsStationTileBlocked(tile)) {
					old_company->infrastructure.rail[GetRailType(tile)]--;
					new_company->infrastructure.rail[GetRailType(tile)]++;
				}
				break;

			case STATION_BUS:
			case STATION_TRUCK:
				/* Road stops were already handled above. */
				break;

			case STATION_BUOY:
			case STATION_DOCK:
				if (GetWaterClass(tile) == WATER_CLASS_CANAL) {
					old_company->infrastructure.water--;
					new_company->infrastructure.water++;
				}
				break;

			default:
				break;
		}

		/* Update station tile count. */
		if (!IsBuoy(tile) && !IsAirport(tile)) {
			old_company->infrastructure.station--;
			new_company->infrastructure.station++;
		}

		/* for buoys, owner of tile is owner of water, st->owner == OWNER_NONE */
		SetTileOwner(tile, new_owner);
		InvalidateWindowClassesData(WC_STATION_LIST, 0);
	} else {
		if (IsDriveThroughStopTile(tile)) {
			/* Remove the drive-through road stop */
			DoCommand(tile, 1 | 1 << 8, (GetStationType(tile) == STATION_TRUCK) ? ROADSTOP_TRUCK : ROADSTOP_BUS, DC_EXEC | DC_BANKRUPT, CMD_REMOVE_ROAD_STOP);
			assert(IsTileType(tile, MP_ROAD));
			/* Change owner of tile and all roadtypes */
			ChangeTileOwner(tile, old_owner, new_owner);
		} else {
			DoCommand(tile, 0, 0, DC_EXEC | DC_BANKRUPT, CMD_LANDSCAPE_CLEAR);
			/* Set tile owner of water under (now removed) buoy and dock to OWNER_NONE.
			 * Update owner of buoy if it was not removed (was in orders).
			 * Do not update when owned by OWNER_WATER (sea and rivers). */
			if ((IsTileType(tile, MP_WATER) || IsBuoyTile(tile)) && IsTileOwner(tile, old_owner)) SetTileOwner(tile, OWNER_NONE);
		}
	}
}

/**
 * Check if a drive-through road stop tile can be cleared.
 * Road stops built on town-owned roads check the conditions
 * that would allow clearing of the original road.
 * @param tile road stop tile to check
 * @param flags command flags
 * @return true if the road can be cleared
 */
static bool CanRemoveRoadWithStop(TileIndex tile, DoCommandFlag flags)
{
	/* Yeah... water can always remove stops, right? */
	if (_current_company == OWNER_WATER) return true;

	RoadTypes rts = GetRoadTypes(tile);
	if (HasBit(rts, ROADTYPE_TRAM)) {
		Owner tram_owner = GetRoadOwner(tile, ROADTYPE_TRAM);
		if (tram_owner != OWNER_NONE && CheckOwnership(tram_owner).Failed()) return false;
	}
	if (HasBit(rts, ROADTYPE_ROAD)) {
		Owner road_owner = GetRoadOwner(tile, ROADTYPE_ROAD);
		if (road_owner != OWNER_TOWN) {
			if (road_owner != OWNER_NONE && CheckOwnership(road_owner).Failed()) return false;
		} else {
			if (CheckAllowRemoveRoad(tile, GetAnyRoadBits(tile, ROADTYPE_ROAD), OWNER_TOWN, ROADTYPE_ROAD, flags).Failed()) return false;
		}
	}

	return true;
}

/**
 * Clear a single tile of a station.
 * @param tile The tile to clear.
 * @param flags The DoCommand flags related to the "command".
 * @return The cost, or error of clearing.
 */
CommandCost ClearTile_Station(TileIndex tile, DoCommandFlag flags)
{
	if (flags & DC_AUTO) {
		switch (GetStationType(tile)) {
			default: break;
			case STATION_RAIL:     return_cmd_error(STR_ERROR_MUST_DEMOLISH_RAILROAD);
			case STATION_WAYPOINT: return_cmd_error(STR_ERROR_BUILDING_MUST_BE_DEMOLISHED);
			case STATION_AIRPORT:  return_cmd_error(STR_ERROR_MUST_DEMOLISH_AIRPORT_FIRST);
			case STATION_TRUCK:    return_cmd_error(HasTileRoadType(tile, ROADTYPE_TRAM) ? STR_ERROR_MUST_DEMOLISH_CARGO_TRAM_STATION_FIRST : STR_ERROR_MUST_DEMOLISH_TRUCK_STATION_FIRST);
			case STATION_BUS:      return_cmd_error(HasTileRoadType(tile, ROADTYPE_TRAM) ? STR_ERROR_MUST_DEMOLISH_PASSENGER_TRAM_STATION_FIRST : STR_ERROR_MUST_DEMOLISH_BUS_STATION_FIRST);
			case STATION_BUOY:     return_cmd_error(STR_ERROR_BUOY_IN_THE_WAY);
			case STATION_DOCK:     return_cmd_error(STR_ERROR_MUST_DEMOLISH_DOCK_FIRST);
			case STATION_OILRIG:
				SetDParam(1, STR_INDUSTRY_NAME_OIL_RIG);
				return_cmd_error(STR_ERROR_GENERIC_OBJECT_IN_THE_WAY);
		}
	}

	switch (GetStationType(tile)) {
		case STATION_RAIL:     return RemoveRailStation(tile, flags);
		case STATION_WAYPOINT: return RemoveRailWaypoint(tile, flags);
		case STATION_AIRPORT:  return RemoveAirport(tile, flags);
		case STATION_TRUCK:
			if (IsDriveThroughStopTile(tile) && !CanRemoveRoadWithStop(tile, flags)) {
				return_cmd_error(STR_ERROR_MUST_DEMOLISH_TRUCK_STATION_FIRST);
			}
			return RemoveRoadStop(tile, flags);
		case STATION_BUS:
			if (IsDriveThroughStopTile(tile) && !CanRemoveRoadWithStop(tile, flags)) {
				return_cmd_error(STR_ERROR_MUST_DEMOLISH_BUS_STATION_FIRST);
			}
			return RemoveRoadStop(tile, flags);
		case STATION_BUOY:     return RemoveBuoy(tile, flags);
		case STATION_DOCK:     return RemoveDock(tile, flags);
		default: break;
	}

	return CMD_ERROR;
}

static CommandCost TerraformTile_Station(TileIndex tile, DoCommandFlag flags, int z_new, Slope tileh_new)
{
	if (_settings_game.construction.build_on_slopes && AutoslopeEnabled()) {
		/* TODO: If you implement newgrf callback 149 'land slope check', you have to decide what to do with it here.
		 *       TTDP does not call it.
		 */
		if (GetTileMaxZ(tile) == z_new + GetSlopeMaxZ(tileh_new)) {
			switch (GetStationType(tile)) {
				case STATION_WAYPOINT:
				case STATION_RAIL: {
					DiagDirection direction = AxisToDiagDir(GetRailStationAxis(tile));
					if (!AutoslopeCheckForEntranceEdge(tile, z_new, tileh_new, direction)) break;
					if (!AutoslopeCheckForEntranceEdge(tile, z_new, tileh_new, ReverseDiagDir(direction))) break;
					return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
				}

				case STATION_AIRPORT:
					return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);

				case STATION_TRUCK:
				case STATION_BUS: {
					DiagDirection direction = GetRoadStopDir(tile);
					if (!AutoslopeCheckForEntranceEdge(tile, z_new, tileh_new, direction)) break;
					if (IsDriveThroughStopTile(tile)) {
						if (!AutoslopeCheckForEntranceEdge(tile, z_new, tileh_new, ReverseDiagDir(direction))) break;
					}
					return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
				}

				default: break;
			}
		}
	}
	return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
}

/**
 * Get flow for a station.
 * @param st Station to get flow for.
 * @return Flow for st.
 */
uint FlowStat::GetShare(StationID st) const
{
	uint32 prev = 0;
	for (SharesMap::const_iterator it = this->shares.begin(); it != this->shares.end(); ++it) {
		if (it->second == st) {
			return it->first - prev;
		} else {
			prev = it->first;
		}
	}
	return 0;
}

/**
 * Get a station a package can be routed to, but exclude the given ones.
 * @param excluded StationID not to be selected.
 * @param excluded2 Another StationID not to be selected.
 * @return A station ID from the shares map.
 */
StationID FlowStat::GetVia(StationID excluded, StationID excluded2) const
{
	if (this->unrestricted == 0) return INVALID_STATION;
	assert(!this->shares.empty());
	SharesMap::const_iterator it = this->shares.upper_bound(RandomRange(this->unrestricted));
	assert(it != this->shares.end() && it->first <= this->unrestricted);
	if (it->second != excluded && it->second != excluded2) return it->second;

	/* We've hit one of the excluded stations.
	 * Draw another share, from outside its range. */

	uint end = it->first;
	uint begin = (it == this->shares.begin() ? 0 : (--it)->first);
	uint interval = end - begin;
	if (interval >= this->unrestricted) return INVALID_STATION; // Only one station in the map.
	uint new_max = this->unrestricted - interval;
	uint rand = RandomRange(new_max);
	SharesMap::const_iterator it2 = (rand < begin) ? this->shares.upper_bound(rand) :
			this->shares.upper_bound(rand + interval);
	assert(it2 != this->shares.end() && it2->first <= this->unrestricted);
	if (it2->second != excluded && it2->second != excluded2) return it2->second;

	/* We've hit the second excluded station.
	 * Same as before, only a bit more complicated. */

	uint end2 = it2->first;
	uint begin2 = (it2 == this->shares.begin() ? 0 : (--it2)->first);
	uint interval2 = end2 - begin2;
	if (interval2 >= new_max) return INVALID_STATION; // Only the two excluded stations in the map.
	new_max -= interval2;
	if (begin > begin2) {
		Swap(begin, begin2);
		Swap(end, end2);
		Swap(interval, interval2);
	}
	rand = RandomRange(new_max);
	SharesMap::const_iterator it3 = this->shares.upper_bound(this->unrestricted);
	if (rand < begin) {
		it3 = this->shares.upper_bound(rand);
	} else if (rand < begin2 - interval) {
		it3 = this->shares.upper_bound(rand + interval);
	} else {
		it3 = this->shares.upper_bound(rand + interval + interval2);
	}
	assert(it3 != this->shares.end() && it3->first <= this->unrestricted);
	return it3->second;
}

/**
 * Reduce all flows to minimum capacity so that they don't get in the way of
 * link usage statistics too much. Keep them around, though, to continue
 * routing any remaining cargo.
 */
void FlowStat::Invalidate()
{
	assert(!this->shares.empty());
	SharesMap new_shares;
	uint i = 0;
	for (SharesMap::iterator it(this->shares.begin()); it != this->shares.end(); ++it) {
		new_shares[++i] = it->second;
		if (it->first == this->unrestricted) this->unrestricted = i;
	}
	this->shares.swap(new_shares);
	assert(!this->shares.empty() && this->unrestricted <= (--this->shares.end())->first);
}

/**
 * Change share for specified station. By specifing INT_MIN as parameter you
 * can erase a share. Newly added flows will be unrestricted.
 * @param st Next Hop to be removed.
 * @param flow Share to be added or removed.
 */
void FlowStat::ChangeShare(StationID st, int flow)
{
	/* We assert only before changing as afterwards the shares can actually
	 * be empty. In that case the whole flow stat must be deleted then. */
	assert(!this->shares.empty());

	uint removed_shares = 0;
	uint added_shares = 0;
	uint last_share = 0;
	SharesMap new_shares;
	for (SharesMap::iterator it(this->shares.begin()); it != this->shares.end(); ++it) {
		if (it->second == st) {
			if (flow < 0) {
				uint share = it->first - last_share;
				if (flow == INT_MIN || (uint)(-flow) >= share) {
					removed_shares += share;
					if (it->first <= this->unrestricted) this->unrestricted -= share;
					if (flow != INT_MIN) flow += share;
					last_share = it->first;
					continue; // remove the whole share
				}
				removed_shares += (uint)(-flow);
			} else {
				added_shares += (uint)(flow);
			}
			if (it->first <= this->unrestricted) this->unrestricted += flow;

			/* If we don't continue above the whole flow has been added or
			 * removed. */
			flow = 0;
		}
		new_shares[it->first + added_shares - removed_shares] = it->second;
		last_share = it->first;
	}
	if (flow > 0) {
		new_shares[last_share + (uint)flow] = st;
		if (this->unrestricted < last_share) {
			this->ReleaseShare(st);
		} else {
			this->unrestricted += flow;
		}
	}
	this->shares.swap(new_shares);
}

/**
 * Restrict a flow by moving it to the end of the map and decreasing the amount
 * of unrestricted flow.
 * @param st Station of flow to be restricted.
 */
void FlowStat::RestrictShare(StationID st)
{
	assert(!this->shares.empty());
	uint flow = 0;
	uint last_share = 0;
	SharesMap new_shares;
	for (SharesMap::iterator it(this->shares.begin()); it != this->shares.end(); ++it) {
		if (flow == 0) {
			if (it->first > this->unrestricted) return; // Not present or already restricted.
			if (it->second == st) {
				flow = it->first - last_share;
				this->unrestricted -= flow;
			} else {
				new_shares[it->first] = it->second;
			}
		} else {
			new_shares[it->first - flow] = it->second;
		}
		last_share = it->first;
	}
	if (flow == 0) return;
	new_shares[last_share + flow] = st;
	this->shares.swap(new_shares);
	assert(!this->shares.empty());
}

/**
 * Release ("unrestrict") a flow by moving it to the begin of the map and
 * increasing the amount of unrestricted flow.
 * @param st Station of flow to be released.
 */
void FlowStat::ReleaseShare(StationID st)
{
	assert(!this->shares.empty());
	uint flow = 0;
	uint next_share = 0;
	bool found = false;
	for (SharesMap::reverse_iterator it(this->shares.rbegin()); it != this->shares.rend(); ++it) {
		if (it->first < this->unrestricted) return; // Note: not <= as the share may hit the limit.
		if (found) {
			flow = next_share - it->first;
			this->unrestricted += flow;
			break;
		} else {
			if (it->first == this->unrestricted) return; // !found -> Limit not hit.
			if (it->second == st) found = true;
		}
		next_share = it->first;
	}
	if (flow == 0) return;
	SharesMap new_shares;
	new_shares[flow] = st;
	for (SharesMap::iterator it(this->shares.begin()); it != this->shares.end(); ++it) {
		if (it->second != st) {
			new_shares[flow + it->first] = it->second;
		} else {
			flow = 0;
		}
	}
	this->shares.swap(new_shares);
	assert(!this->shares.empty());
}

/**
 * Scale all shares from link graph's runtime to monthly values.
 * @param runtime Time the link graph has been running without compression.
 * @pre runtime must be greater than 0 as we don't want infinite flow values.
 */
void FlowStat::ScaleToMonthly(uint runtime)
{
	assert(runtime > 0);
	SharesMap new_shares;
	uint share = 0;
	for (SharesMap::iterator i = this->shares.begin(); i != this->shares.end(); ++i) {
		share = max(share + 1, i->first * 30 / runtime);
		new_shares[share] = i->second;
		if (this->unrestricted == i->first) this->unrestricted = share;
	}
	this->shares.swap(new_shares);
}

/**
 * Add some flow from "origin", going via "via".
 * @param origin Origin of the flow.
 * @param via Next hop.
 * @param flow Amount of flow to be added.
 */
void FlowStatMap::AddFlow(StationID origin, StationID via, uint flow)
{
	FlowStatMap::iterator origin_it = this->find(origin);
	if (origin_it == this->end()) {
		this->insert(std::make_pair(origin, FlowStat(via, flow)));
	} else {
		origin_it->second.ChangeShare(via, flow);
		assert(!origin_it->second.GetShares()->empty());
	}
}

/**
 * Pass on some flow, remembering it as invalid, for later subtraction from
 * locally consumed flow. This is necessary because we can't have negative
 * flows and we don't want to sort the flows before adding them up.
 * @param origin Origin of the flow.
 * @param via Next hop.
 * @param flow Amount of flow to be passed.
 */
void FlowStatMap::PassOnFlow(StationID origin, StationID via, uint flow)
{
	FlowStatMap::iterator prev_it = this->find(origin);
	if (prev_it == this->end()) {
		FlowStat fs(via, flow);
		fs.AppendShare(INVALID_STATION, flow);
		this->insert(std::make_pair(origin, fs));
	} else {
		prev_it->second.ChangeShare(via, flow);
		prev_it->second.ChangeShare(INVALID_STATION, flow);
		assert(!prev_it->second.GetShares()->empty());
	}
}

/**
 * Subtract invalid flows from locally consumed flow.
 * @param self ID of own station.
 */
void FlowStatMap::FinalizeLocalConsumption(StationID self)
{
	for (FlowStatMap::iterator i = this->begin(); i != this->end(); ++i) {
		FlowStat &fs = i->second;
		uint local = fs.GetShare(INVALID_STATION);
		if (local > INT_MAX) { // make sure it fits in an int
			fs.ChangeShare(self, -INT_MAX);
			fs.ChangeShare(INVALID_STATION, -INT_MAX);
			local -= INT_MAX;
		}
		fs.ChangeShare(self, -(int)local);
		fs.ChangeShare(INVALID_STATION, -(int)local);

		/* If the local share is used up there must be a share for some
		 * remote station. */
		assert(!fs.GetShares()->empty());
	}
}

/**
 * Delete all flows at a station for specific cargo and destination.
 * @param via Remote station of flows to be deleted.
 * @return IDs of source stations for which the complete FlowStat, not only a
 *         share, has been erased.
 */
StationIDStack FlowStatMap::DeleteFlows(StationID via)
{
	StationIDStack ret;
	for (FlowStatMap::iterator f_it = this->begin(); f_it != this->end();) {
		FlowStat &s_flows = f_it->second;
		s_flows.ChangeShare(via, INT_MIN);
		if (s_flows.GetShares()->empty()) {
			ret.Push(f_it->first);
			this->erase(f_it++);
		} else {
			++f_it;
		}
	}
	return ret;
}

/**
 * Restrict all flows at a station for specific cargo and destination.
 * @param via Remote station of flows to be restricted.
 */
void FlowStatMap::RestrictFlows(StationID via)
{
	for (FlowStatMap::iterator it = this->begin(); it != this->end(); ++it) {
		it->second.RestrictShare(via);
	}
}

/**
 * Release all flows at a station for specific cargo and destination.
 * @param via Remote station of flows to be released.
 */
void FlowStatMap::ReleaseFlows(StationID via)
{
	for (FlowStatMap::iterator it = this->begin(); it != this->end(); ++it) {
		it->second.ReleaseShare(via);
	}
}

/**
 * Get the sum of all flows from this FlowStatMap.
 * @return sum of all flows.
 */
uint FlowStatMap::GetFlow() const
{
	uint ret = 0;
	for (FlowStatMap::const_iterator i = this->begin(); i != this->end(); ++i) {
		ret += (--(i->second.GetShares()->end()))->first;
	}
	return ret;
}

/**
 * Get the sum of flows via a specific station from this FlowStatMap.
 * @param via Remote station to look for.
 * @return all flows for 'via' added up.
 */
uint FlowStatMap::GetFlowVia(StationID via) const
{
	uint ret = 0;
	for (FlowStatMap::const_iterator i = this->begin(); i != this->end(); ++i) {
		ret += i->second.GetShare(via);
	}
	return ret;
}

/**
 * Get the sum of flows from a specific station from this FlowStatMap.
 * @param from Origin station to look for.
 * @return all flows from 'from' added up.
 */
uint FlowStatMap::GetFlowFrom(StationID from) const
{
	FlowStatMap::const_iterator i = this->find(from);
	if (i == this->end()) return 0;
	return (--(i->second.GetShares()->end()))->first;
}

/**
 * Get the flow from a specific station via a specific other station.
 * @param from Origin station to look for.
 * @param via Remote station to look for.
 * @return flow share originating at 'from' and going to 'via'.
 */
uint FlowStatMap::GetFlowFromVia(StationID from, StationID via) const
{
	FlowStatMap::const_iterator i = this->find(from);
	if (i == this->end()) return 0;
	return i->second.GetShare(via);
}

extern const TileTypeProcs _tile_type_station_procs = {
	DrawTile_Station,           // draw_tile_proc
	GetSlopePixelZ_Station,     // get_slope_z_proc
	ClearTile_Station,          // clear_tile_proc
	NULL,                       // add_accepted_cargo_proc
	GetTileDesc_Station,        // get_tile_desc_proc
	GetTileTrackStatus_Station, // get_tile_track_status_proc
	ClickTile_Station,          // click_tile_proc
	AnimateTile_Station,        // animate_tile_proc
	TileLoop_Station,           // tile_loop_proc
	ChangeTileOwner_Station,    // change_tile_owner_proc
	NULL,                       // add_produced_cargo_proc
	VehicleEnter_Station,       // vehicle_enter_tile_proc
	GetFoundation_Station,      // get_foundation_proc
	TerraformTile_Station,      // terraform_tile_proc
};