/* $Id$ */

/** @file bridge_gui.cpp Graphical user interface for bridge construction */

#include "stdafx.h"
#include "openttd.h"
#include "gui.h"
#include "window_gui.h"
#include "command_func.h"
#include "economy_func.h"
#include "variables.h"
#include "bridge.h"
#include "strings_func.h"
#include "window_func.h"
#include "sound_func.h"
#include "map_func.h"
#include "viewport_func.h"
#include "gfx_func.h"
#include "tunnelbridge.h"
#include "sortlist_type.h"
#include "widgets/dropdown_func.h"

#include "table/strings.h"

/* Save the sorting during runtime */
static Listing _bridge_sorting = {false, 0};

/**
 * Carriage for the data we need if we want to build a bridge
 */
struct BuildBridgeData {
	BridgeType index;
	const BridgeSpec *spec;
	Money cost;
};

typedef GUIList<BuildBridgeData> GUIBridgeList;

/** Sort the bridges by their index */
static int CDECL BridgeIndexSorter(const void *a, const void *b)
{
	const BuildBridgeData* ba = (BuildBridgeData*)a;
	const BuildBridgeData* bb = (BuildBridgeData*)b;
	int r = ba->index - bb->index;

	return (_bridge_sorting.order) ? -r : r;
}

/** Sort the bridges by their price */
static int CDECL BridgePriceSorter(const void *a, const void *b)
{
	const BuildBridgeData* ba = (BuildBridgeData*)a;
	const BuildBridgeData* bb = (BuildBridgeData*)b;
	int r = ba->cost - bb->cost;

	return (_bridge_sorting.order) ? -r : r;
}

/** Sort the bridges by their maximum speed */
static int CDECL BridgeSpeedSorter(const void *a, const void *b)
{
	const BuildBridgeData* ba = (BuildBridgeData*)a;
	const BuildBridgeData* bb = (BuildBridgeData*)b;
	int r = ba->spec->speed - bb->spec->speed;

	return (_bridge_sorting.order) ? -r : r;
}

typedef int CDECL BridgeSortListingTypeFunction(const void*, const void*);

/* Availible bridge sorting functions */
static BridgeSortListingTypeFunction* const _bridge_sorter[] = {
	&BridgeIndexSorter,
	&BridgePriceSorter,
	&BridgeSpeedSorter
};

/* Names of the sorting functions */
static const StringID _bridge_sort_listing[] = {
	STR_SORT_BY_NUMBER,
	STR_ENGINE_SORT_COST,
	STR_SORT_BY_MAX_SPEED,
	INVALID_STRING_ID
};

/**
 * Callback executed after a build Bridge CMD has been called
 *
 * @param scucess True if the build succeded
 * @param tile The tile where the command has been executed
 * @param p1 not used
 * @param p2 not used
 */
void CcBuildBridge(bool success, TileIndex tile, uint32 p1, uint32 p2)
{
	if (success) SndPlayTileFx(SND_27_BLACKSMITH_ANVIL, tile);
}

/* Names of the build bridge selection window */
enum BuildBridgeSelectionWidgets {
	BBSW_CLOSEBOX = 0,
	BBSW_CAPTION,
	BBSW_DROPDOWN_ORDER,
	BBSW_DROPDOWN_CRITERIA,
	BBSW_BRIDGE_LIST,
	BBSW_SCROLLBAR,
	BBSW_RESIZEBOX
};

class BuildBridgeWindow : public Window {
private:
	/* The last size of the build bridge window
	 * is saved during runtime */
	static uint last_size;

	TileIndex start_tile;
	TileIndex end_tile;
	uint32 type;
	GUIBridgeList *bridges;

	void BuildBridge(uint8 i)
	{
		DoCommandP(this->end_tile, this->start_tile, this->type | this->bridges->sort_list[i].index,
				CcBuildBridge, CMD_BUILD_BRIDGE | CMD_MSG(STR_5015_CAN_T_BUILD_BRIDGE_HERE));
	}

	/** Sort the builable bridges */
	void SortBridgeList()
	{
		/* Skip sorting if resort bit is not set */
		if (!(bridges->flags & VL_RESORT)) return;

		qsort(this->bridges->sort_list, this->bridges->list_length, sizeof(this->bridges->sort_list[0]), _bridge_sorter[_bridge_sorting.criteria]);

		/* Display the current sort variant */
		this->widget[BBSW_DROPDOWN_CRITERIA].data = _bridge_sort_listing[this->bridges->sort_type];

		bridges->flags &= ~VL_RESORT;

		/* Set the modified widgets dirty */
		this->InvalidateWidget(BBSW_DROPDOWN_CRITERIA);
		this->InvalidateWidget(BBSW_BRIDGE_LIST);
	}

public:
	BuildBridgeWindow(const WindowDesc *desc, TileIndex start, TileIndex end, uint32 br_type, GUIBridgeList *bl) : Window(desc),
		start_tile(start),
		end_tile(end),
		type(br_type),
		bridges(bl)
	{
		this->SortBridgeList();

		/* Change the data, or the caption of the gui. Set it to road or rail, accordingly */
		this->widget[BBSW_CAPTION].data = (GB(this->type, 15, 2) == TRANSPORT_ROAD) ? STR_1803_SELECT_ROAD_BRIDGE : STR_100D_SELECT_RAIL_BRIDGE;

		this->resize.step_height = 22;
		this->vscroll.count = bl->list_length;

		if (this->last_size <= 4) {
			this->vscroll.cap = 4;
		} else {
			/* Resize the bridge selection window if we used a bigger one the last time */
			this->vscroll.cap = (this->vscroll.count > this->last_size) ? this->last_size : this->vscroll.count;
			ResizeWindow(this, 0, (this->vscroll.cap - 4) * this->resize.step_height);
			this->widget[BBSW_BRIDGE_LIST].data = (this->vscroll.cap << 8) + 1;
		}

		this->FindWindowPlacementAndResize(desc);
	}

	~BuildBridgeWindow()
	{
		free(this->bridges->sort_list);
		delete bridges;
	}

	virtual void OnPaint()
	{
		this->DrawWidgets();

		this->DrawSortButtonState(BBSW_DROPDOWN_ORDER, (this->bridges->flags & VL_DESC) ? SBS_DOWN : SBS_UP);

		uint y = this->widget[BBSW_BRIDGE_LIST].top + 2;

		for (int i = this->vscroll.pos; (i < (this->vscroll.cap + this->vscroll.pos)) && (i < this->bridges->list_length); i++) {
			const BridgeSpec *b = this->bridges->sort_list[i].spec;

			SetDParam(2, this->bridges->sort_list[i].cost);
			SetDParam(1, b->speed * 10 / 16);
			SetDParam(0, b->material);

			DrawSprite(b->sprite, b->pal, 3, y);
			DrawString(44, y, STR_500D, TC_FROMSTRING);
			y += this->resize.step_height;

		}
	}

	virtual EventState OnKeyPress(uint16 key, uint16 keycode)
	{
		const uint8 i = keycode - '1';
		if (i < 9 && i < this->bridges->list_length) {
			/* Build the requested bridge */
			this->BuildBridge(i);
			delete this;
			return ES_HANDLED;
		}
		return ES_NOT_HANDLED;
	}

	virtual void OnClick(Point pt, int widget)
	{
		switch (widget) {
			default: break;
			case BBSW_BRIDGE_LIST: {
				uint i = ((int)pt.y - this->widget[BBSW_BRIDGE_LIST].top) / this->resize.step_height;
				if (i < this->vscroll.cap) {
					i += this->vscroll.pos;
					if (i < this->bridges->list_length) {
						this->BuildBridge(i);
						delete this;
					}
				}
			} break;

			case BBSW_DROPDOWN_ORDER:
				/* Revers the sort order */
				this->bridges->flags ^= VL_DESC;
				_bridge_sorting.order = !_bridge_sorting.order;

				this->bridges->flags |= VL_RESORT;
				this->SortBridgeList();
				break;

			case BBSW_DROPDOWN_CRITERIA:
				ShowDropDownMenu(this, _bridge_sort_listing, bridges->sort_type, BBSW_DROPDOWN_CRITERIA, 0, 0);
				break;
		}
	}

	virtual void OnDropdownSelect(int widget, int index)
	{
		if (widget == BBSW_DROPDOWN_CRITERIA && this->bridges->sort_type != index) {
			this->bridges->sort_type = index;
			_bridge_sorting.criteria = index;

			this->bridges->flags |= VL_RESORT;
			this->SortBridgeList();
		}
	}

	virtual void OnResize(Point new_size, Point delta)
	{
		this->vscroll.cap += delta.y / (int)this->resize.step_height;
		this->widget[BBSW_BRIDGE_LIST].data = (this->vscroll.cap << 8) + 1;
		SetVScrollCount(this, this->bridges->list_length);

		this->last_size = this->vscroll.cap;
	}
};

/* Set the default size of the Build Bridge Window */
uint BuildBridgeWindow::last_size = 4;

/* Widget definition for the rail bridge selection window */
static const Widget _build_bridge_widgets[] = {
{   WWT_CLOSEBOX,   RESIZE_NONE,  7,   0,  10,   0,  13, STR_00C5,                    STR_018B_CLOSE_WINDOW},            // BBSW_CLOSEBOX
{    WWT_CAPTION,   RESIZE_NONE,  7,  11, 199,   0,  13, STR_100D_SELECT_RAIL_BRIDGE, STR_018C_WINDOW_TITLE_DRAG_THIS},  // BBSW_CAPTION

{    WWT_TEXTBTN,   RESIZE_NONE,  7,   0,  80,  14,  25, STR_SORT_BY,                 STR_SORT_ORDER_TIP},               // BBSW_DROPDOWN_ORDER
{   WWT_DROPDOWN,   RESIZE_NONE,  7,  81, 199,  14,  25, 0x0,                         STR_SORT_CRITERIA_TIP},            // BBSW_DROPDOWN_CRITERIA

{     WWT_MATRIX, RESIZE_BOTTOM,  7,   0, 187,  26, 113, 0x401,                       STR_101F_BRIDGE_SELECTION_CLICK},  // BBSW_BRIDGE_LIST
{  WWT_SCROLLBAR, RESIZE_BOTTOM,  7, 188, 199,  26, 101, 0x0,                         STR_0190_SCROLL_BAR_SCROLLS_LIST}, // BBSW_SCROLLBAR
{  WWT_RESIZEBOX,     RESIZE_TB,  7, 188, 199, 102, 113, 0x0,                         STR_RESIZE_BUTTON},                // BBSW_RESIZEBOX
{   WIDGETS_END},
};

/* Window definition for the rail bridge selection window */
static const WindowDesc _build_bridge_desc = {
	WDP_AUTO, WDP_AUTO, 200, 114, 200, 114,
	WC_BUILD_BRIDGE, WC_BUILD_TOOLBAR,
	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_RESIZABLE,
	_build_bridge_widgets,
};

/**
 * Add a buildable bridge to the list.
 *  If the list is empty a new one is created.
 *
 * @param bl The list which we want to manage
 * @param item The item to add
 * @return The pointer to the list
 */
static GUIBridgeList *PushBridgeList(GUIBridgeList *bl, BuildBridgeData item)
{
	if (bl == NULL) {
		/* Create the list if needed */
		bl = new GUIBridgeList();
		bl->flags |= VL_RESORT;
		if (_bridge_sorting.order) bl->flags |= VL_DESC;
		bl->list_length = 1;
		bl->sort_type = _bridge_sorting.criteria;
	} else {
		/* Resize the list */
		bl->list_length++;
	}

	bl->sort_list = ReallocT(bl->sort_list, bl->list_length);

	bl->sort_list[bl->list_length - 1] = item;

	return bl;
}

/**
 * Prepare the data for the build a bridge window.
 *  If we can't build a bridge under the given conditions
 *  show an error message.
 *
 * @parma start The start tile of the bridge
 * @param end The end tile of the bridge
 * @param transport_type The transport type
 * @param bridge_type The bridge type
 */
void ShowBuildBridgeWindow(TileIndex start, TileIndex end, TransportType transport_type, byte bridge_type)
{
	DeleteWindowById(WC_BUILD_BRIDGE, 0);

	/* Data type for the bridge.
	 * Bit 16,15 = transport type,
	 *     14..8 = road/rail pieces,
	 *      7..0 = type of bridge */
	uint32 type = (transport_type << 15) | (bridge_type << 8);

	/* only query bridge building possibility once, result is the same for all bridges!
	 * returns CMD_ERROR on failure, and price on success */
	StringID errmsg = INVALID_STRING_ID;
	CommandCost ret = DoCommand(end, start, type, DC_AUTO | DC_QUERY_COST, CMD_BUILD_BRIDGE);

	GUIBridgeList *bl = NULL;
	if (CmdFailed(ret)) {
		errmsg = _error_message;
	} else {
		/* check which bridges can be built
		 * get absolute bridge length
		 * length of the middle parts of the bridge */
		const uint bridge_len = GetTunnelBridgeLength(start, end);
		/* total length of bridge */
		const uint tot_bridgedata_len = CalcBridgeLenCostFactor(bridge_len + 2);

		/* loop for all bridgetypes */
		for (BridgeType brd_type = 0; brd_type != MAX_BRIDGES; brd_type++) {
			if (CheckBridge_Stuff(brd_type, bridge_len)) {
				/* bridge is accepted, add to list */
				BuildBridgeData item;
				item.index = brd_type;
				item.spec = GetBridgeSpec(brd_type);
				/* Add to terraforming & bulldozing costs the cost of the
				 * bridge itself (not computed with DC_QUERY_COST) */
				item.cost = ret.GetCost() + (((int64)tot_bridgedata_len * _price.build_bridge * item.spec->price) >> 8);
				bl = PushBridgeList(bl, item);
			}
		}
	}

	if (bl != NULL) {
		new BuildBridgeWindow(&_build_bridge_desc, start, end, type, bl);
	} else {
		ShowErrorMessage(errmsg, STR_5015_CAN_T_BUILD_BRIDGE_HERE, TileX(end) * TILE_SIZE, TileY(end) * TILE_SIZE);
	}
}