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#include "stdafx.h"

#if defined(WITH_SDL)
#include "openttd.h"
#include "debug.h"
#include "functions.h"
#include "gfx.h"
#include "mixer.h"
#include "window.h"
#include <SDL.h>
#include "player.h"
#include "hal.h"
#include "network.h"
#include "variables.h"

#ifdef UNIX
#include <signal.h>

#ifdef __MORPHOS__
	// The system supplied definition of SIG_DFL is wrong on MorphOS
	#undef SIG_DFL
	#define SIG_DFL (void (*)(int))0
#endif
#endif

#define DYNAMICALLY_LOADED_SDL

static SDL_Surface *_sdl_screen;
static int _sdl_usage;
static bool _all_modes;

#define MAX_DIRTY_RECTS 100
static SDL_Rect _dirty_rects[MAX_DIRTY_RECTS];
static int _num_dirty_rects;

#define SDL_CALL

#if defined(DYNAMICALLY_LOADED_SDL) && defined(WIN32)

bool LoadLibraryList(void **proc, const char *dll);

typedef struct {
	int (SDLCALL *SDL_Init)(Uint32);
	int (SDLCALL *SDL_InitSubSystem)(Uint32);
	char *(SDLCALL *SDL_GetError)();
	void (SDLCALL *SDL_QuitSubSystem)(Uint32);
	void (SDLCALL *SDL_UpdateRect)(SDL_Surface *, Sint32, Sint32, Uint32, Uint32);
	void (SDLCALL *SDL_UpdateRects)(SDL_Surface *, int, SDL_Rect *);
	int (SDLCALL *SDL_SetColors)(SDL_Surface *, SDL_Color *, int, int);
	void (SDLCALL *SDL_WM_SetCaption)(const char *, const char *);
	int (SDLCALL *SDL_ShowCursor)(int);
	void (SDLCALL *SDL_FreeSurface)(SDL_Surface *);
	int (SDLCALL *SDL_PollEvent)(SDL_Event *);
	void (SDLCALL *SDL_WarpMouse)(Uint16, Uint16);
	uint32 (SDLCALL *SDL_GetTicks)();
	int (SDLCALL *SDL_OpenAudio)(SDL_AudioSpec *, SDL_AudioSpec*);
	void (SDLCALL *SDL_PauseAudio)(int);
	void (SDLCALL *SDL_CloseAudio)();
	int (SDLCALL *SDL_LockSurface)(SDL_Surface*);
	void (SDLCALL *SDL_UnlockSurface)(SDL_Surface*);
	SDLMod (SDLCALL *SDL_GetModState)();
	void (SDLCALL *SDL_Delay)(Uint32);
	void (SDLCALL *SDL_Quit)();
	SDL_Surface *(SDLCALL *SDL_SetVideoMode)(int, int, int, Uint32);
	int (SDLCALL *SDL_EnableKeyRepeat)(int, int);
	void (SDLCALL *SDL_EnableUNICODE)(int);
	void (SDLCALL *SDL_VideoDriverName)(char *, int);
	SDL_Rect **(SDLCALL *SDL_ListModes)(void *, int);
	Uint8 *(SDLCALL *SDL_GetKeyState)(int *);
} SDLProcs;

#define M(x) x "\0"
static const char sdl_files[] =
	M("sdl.dll")
	M("SDL_Init")
	M("SDL_InitSubSystem")
	M("SDL_GetError")
	M("SDL_QuitSubSystem")
	M("SDL_UpdateRect")
	M("SDL_UpdateRects")
	M("SDL_SetColors")
	M("SDL_WM_SetCaption")
	M("SDL_ShowCursor")
	M("SDL_FreeSurface")
	M("SDL_PollEvent")
	M("SDL_WarpMouse")
	M("SDL_GetTicks")
	M("SDL_OpenAudio")
	M("SDL_PauseAudio")
	M("SDL_CloseAudio")
	M("SDL_LockSurface")
	M("SDL_UnlockSurface")
	M("SDL_GetModState")
	M("SDL_Delay")
	M("SDL_Quit")
	M("SDL_SetVideoMode")
	M("SDL_EnableKeyRepeat")
	M("SDL_EnableUNICODE")
	M("SDL_VideoDriverName")
	M("SDL_ListModes")
	M("SDL_GetKeyState")
	M("")
;
#undef M

static SDLProcs _proc;

static const char *LoadSdlDLL(void)
{
	if (_proc.SDL_Init != NULL)
		return NULL;
	if (!LoadLibraryList((void**)&_proc, sdl_files))
		return "Unable to load sdl.dll";
	return NULL;
}

#undef SDL_CALL
#define SDL_CALL _proc.

#endif


#ifdef UNIX
static void SdlAbort(int sig)
{
	/* Own hand-made parachute for the cases of failed assertions. */
	SDL_CALL SDL_Quit();

	switch (sig) {
		case SIGSEGV:
		case SIGFPE:
			signal(sig, SIG_DFL);
			raise(sig);
			break;

		default:
			break;
	}
}
#endif


static const char *SdlOpen(uint32 x)
{
#if defined(DYNAMICALLY_LOADED_SDL) && defined(WIN32)
	{
		const char *s = LoadSdlDLL();
		if (s != NULL) return s;
	}
#endif
	if (_sdl_usage++ == 0) {
		if (SDL_CALL SDL_Init(x) == -1)
			return SDL_CALL SDL_GetError();
	} else if (x != 0) {
		if (SDL_CALL SDL_InitSubSystem(x) == -1)
			return SDL_CALL SDL_GetError();
	}

#ifdef UNIX
	signal(SIGABRT, SdlAbort);
	signal(SIGSEGV, SdlAbort);
	signal(SIGFPE, SdlAbort);
#endif

	return NULL;
}

static void SdlClose(uint32 x)
{
	if (x != 0)
		SDL_CALL SDL_QuitSubSystem(x);
	if (--_sdl_usage == 0) {
		SDL_CALL SDL_Quit();
		#ifdef UNIX
		signal(SIGABRT, SIG_DFL);
		signal(SIGSEGV, SIG_DFL);
		signal(SIGFPE, SIG_DFL);
		#endif
	}
}

static void SdlVideoMakeDirty(int left, int top, int width, int height)
{
//	printf("(%d,%d)-(%d,%d)\n", left, top, width, height);
//	_pixels_redrawn += width*height;
	if (_num_dirty_rects < MAX_DIRTY_RECTS) {
		_dirty_rects[_num_dirty_rects].x = left;
		_dirty_rects[_num_dirty_rects].y = top;
		_dirty_rects[_num_dirty_rects].w = width;
		_dirty_rects[_num_dirty_rects].h = height;
	}
	_num_dirty_rects++;
}

static SDL_Color pal[256];

static void UpdatePalette(uint start, uint end)
{
	uint i;

	for (i = start; i != end; i++) {
		pal[i].r = _cur_palette[i].r;
		pal[i].g = _cur_palette[i].g;
		pal[i].b = _cur_palette[i].b;
		pal[i].unused = 0;
	}

	SDL_CALL SDL_SetColors(_sdl_screen, pal, start, end);
}

static void InitPalette(void)
{
	UpdatePalette(0, 256);
}

static void CheckPaletteAnim(void)
{
	if(_pal_last_dirty != -1) {
		UpdatePalette(_pal_first_dirty, _pal_last_dirty + 1);
		_pal_last_dirty = -1;
	}
}

static void DrawSurfaceToScreen(void)
{
	int n = _num_dirty_rects;
	if (n != 0) {
		_num_dirty_rects = 0;
		if (n > MAX_DIRTY_RECTS)
			SDL_CALL SDL_UpdateRect(_sdl_screen, 0, 0, 0, 0);
		else
			SDL_CALL SDL_UpdateRects(_sdl_screen, n, _dirty_rects);
	}
}

static const uint16 default_resolutions[][2] = {
	{ 640,  480},
	{ 800,  600},
	{1024,  768},
	{1152,  864},
	{1280,  800},
	{1280,  960},
	{1280, 1024},
	{1400, 1050},
	{1600, 1200},
	{1680, 1050},
	{1920, 1200}
};

static void GetVideoModes(void)
{
	int i;
	SDL_Rect **modes;

	modes = SDL_CALL SDL_ListModes(NULL, SDL_SWSURFACE + (_fullscreen ? SDL_FULLSCREEN : 0));

	if (modes == NULL)
		error("sdl: no modes available");

	_all_modes = (modes == (void*)-1);

	if (_all_modes) {
		// all modes available, put some default ones here
		memcpy(_resolutions, default_resolutions, sizeof(default_resolutions));
		_num_resolutions = lengthof(default_resolutions);
	} else {
		int n = 0;
		for (i = 0; modes[i]; i++) {
			int w = modes[i]->w;
			int h = modes[i]->h;
			if (IS_INT_INSIDE(w, 640, MAX_SCREEN_WIDTH + 1) &&
					IS_INT_INSIDE(h, 480, MAX_SCREEN_HEIGHT + 1)) {
				int j;
				for (j = 0; j < n; j++) {
					if (_resolutions[j][0] == w && _resolutions[j][1] == h) break;
				}

				if (j == n) {
					_resolutions[j][0] = w;
					_resolutions[j][1] = h;
					if (++n == lengthof(_resolutions)) break;
				}
			}
		}
		_num_resolutions = n;
		SortResolutions(_num_resolutions);
	}
}

static int GetAvailableVideoMode(int *w, int *h)
{
	int i;
	int best;
	uint delta;

	// all modes available?
	if (_all_modes)
		return 1;

	// is the wanted mode among the available modes?
	for (i = 0; i != _num_resolutions; i++) {
		if(*w == _resolutions[i][0] && *h == _resolutions[i][1])
			return 1;
	}

	// use the closest possible resolution
	best = 0;
	delta = abs((_resolutions[0][0] - *w) * (_resolutions[0][1] - *h));
	for (i = 1; i != _num_resolutions; ++i) {
		uint newdelta = abs((_resolutions[i][0] - *w) * (_resolutions[i][1] - *h));
		if (newdelta < delta) {
			best = i;
			delta = newdelta;
		}
	}
	*w = _resolutions[best][0];
	*h = _resolutions[best][1];
	return 2;
}

extern const char _openttd_revision[];

static bool CreateMainSurface(int w, int h)
{
	SDL_Surface *newscreen;
	char caption[50];

	GetAvailableVideoMode(&w, &h);

	DEBUG(misc, 1) ("sdl: using mode %dx%d", w, h);

	// DO NOT CHANGE TO HWSURFACE, IT DOES NOT WORK
	newscreen = SDL_CALL SDL_SetVideoMode(w, h, 8, SDL_SWSURFACE | SDL_HWPALETTE | (_fullscreen ? SDL_FULLSCREEN : SDL_RESIZABLE));
	if (newscreen == NULL)
		return false;

	_screen.width = newscreen->w;
	_screen.height = newscreen->h;
	_screen.pitch = newscreen->pitch;

	_sdl_screen = newscreen;
	InitPalette();

	snprintf(caption, sizeof(caption), "OpenTTD %s", _openttd_revision);
	SDL_CALL SDL_WM_SetCaption(caption, caption);
	SDL_CALL SDL_ShowCursor(0);

	GameSizeChanged();

	return true;
}

typedef struct VkMapping {
	uint16 vk_from;
	byte vk_count;
	byte map_to;
} VkMapping;

#define AS(x, z) {x, 0, z}
#define AM(x, y, z, w) {x, y - x, z}

static const VkMapping _vk_mapping[] = {
	// Pageup stuff + up/down
	AM(SDLK_PAGEUP, SDLK_PAGEDOWN, WKC_PAGEUP, WKC_PAGEDOWN),
	AS(SDLK_UP,			WKC_UP),
	AS(SDLK_DOWN,		WKC_DOWN),
	AS(SDLK_LEFT,		WKC_LEFT),
	AS(SDLK_RIGHT,	WKC_RIGHT),

	AS(SDLK_HOME,		WKC_HOME),
	AS(SDLK_END,		WKC_END),

	AS(SDLK_INSERT,	WKC_INSERT),
	AS(SDLK_DELETE,	WKC_DELETE),

	// Map letters & digits
	AM(SDLK_a, SDLK_z, 'A', 'Z'),
	AM(SDLK_0, SDLK_9, '0', '9'),

	AS(SDLK_ESCAPE,	WKC_ESC),
	AS(SDLK_PAUSE,  WKC_PAUSE),
	AS(SDLK_BACKSPACE,	WKC_BACKSPACE),

	AS(SDLK_SPACE,		WKC_SPACE),
	AS(SDLK_RETURN,		WKC_RETURN),
	AS(SDLK_TAB,			WKC_TAB),

	// Function keys
	AM(SDLK_F1, SDLK_F12, WKC_F1, WKC_F12),

	// Numeric part.
	// What is the virtual keycode for numeric enter??
	AM(SDLK_KP0, SDLK_KP9, WKC_NUM_0, WKC_NUM_9),
	AS(SDLK_KP_DIVIDE,		WKC_NUM_DIV),
	AS(SDLK_KP_MULTIPLY,	WKC_NUM_MUL),
	AS(SDLK_KP_MINUS,			WKC_NUM_MINUS),
	AS(SDLK_KP_PLUS,			WKC_NUM_PLUS),
	AS(SDLK_KP_ENTER,			WKC_NUM_ENTER),
	AS(SDLK_KP_PERIOD,		WKC_NUM_DECIMAL)
};

static uint32 ConvertSdlKeyIntoMy(SDL_keysym *sym)
{
	const VkMapping *map;
	uint key = 0;
	for (map = _vk_mapping; map != endof(_vk_mapping); ++map) {
		if ((uint)(sym->sym - map->vk_from) <= map->vk_count) {
			key = sym->sym - map->vk_from + map->map_to;
			break;
		}
	}

	// check scancode for BACKQUOTE key, because we want the key left of "1", not anything else (on non-US keyboards)
#if defined(WIN32) || defined(__OS2__)
	if (sym->scancode == 41) key |= WKC_BACKQUOTE;
#elif defined(__APPLE__)
	if (sym->scancode == 10) key |= WKC_BACKQUOTE;
#elif defined(__MORPHOS__)
	if (sym->scancode == 0)  key |= WKC_BACKQUOTE;  // yes, that key is code '0' under MorphOS :)
#elif defined(__BEOS__)
	if (sym->scancode == 17)  key |= WKC_BACKQUOTE;
#elif defined(__SVR4) && defined(__sun)
	if (sym->scancode == 60) key |= WKC_BACKQUOTE;
	if (sym->scancode == 49) key |= WKC_BACKSPACE;
#elif defined(__sgi__)
	if (sym->scancode == 22) key |= WKC_BACKQUOTE;
#else
	if (sym->scancode == 41) key |= WKC_BACKQUOTE; // Linux console
	if (sym->scancode == 49) key |= WKC_BACKQUOTE;
#endif

	// META are the command keys on mac
	if (sym->mod & KMOD_META) key |= WKC_META;
	if (sym->mod & KMOD_SHIFT) key |= WKC_SHIFT;
	if (sym->mod & KMOD_CTRL) key |= WKC_CTRL;
	if (sym->mod & KMOD_ALT) key |= WKC_ALT;
	// these two lines really help porting hotkey combos. Uncomment to use -- Bjarni
	//printf("scancode character pressed %d\n", sym->scancode);
	//printf("unicode character pressed %d\n", sym->unicode);
	return (key << 16) + sym->unicode;
}

extern void DoExitSave(void);

static int PollEvent(void)
{
	SDL_Event ev;

	if (!SDL_CALL SDL_PollEvent(&ev))
		return -2;

	switch (ev.type) {
	case SDL_MOUSEMOTION:
		if (_cursor.fix_at) {
			int dx = ev.motion.x - _cursor.pos.x;
			int dy = ev.motion.y - _cursor.pos.y;
			if (dx != 0 || dy != 0) {
				_cursor.delta.x += dx;
				_cursor.delta.y += dy;
				SDL_CALL SDL_WarpMouse(_cursor.pos.x, _cursor.pos.y);
			}
		} else {
			_cursor.delta.x = ev.motion.x - _cursor.pos.x;
			_cursor.delta.y = ev.motion.y - _cursor.pos.y;
			_cursor.pos.x = ev.motion.x;
			_cursor.pos.y = ev.motion.y;
			_cursor.dirty = true;
		}
		break;

	case SDL_MOUSEBUTTONDOWN:
		if (_rightclick_emulate && (SDL_CALL SDL_GetModState() & (KMOD_LCTRL | KMOD_RCTRL)))
			ev.button.button = SDL_BUTTON_RIGHT;

		switch (ev.button.button) {
			case SDL_BUTTON_LEFT:
				_left_button_down = true;
				break;
			case SDL_BUTTON_RIGHT:
				_right_button_down = true;
				_right_button_clicked = true;
				break;
			case SDL_BUTTON_WHEELUP:
				_cursor.wheel--;
				break;
			case SDL_BUTTON_WHEELDOWN:
				_cursor.wheel++;
				break;
			default:
				break;
		}
		break;

	case SDL_MOUSEBUTTONUP:
		if (_rightclick_emulate) {
			_right_button_down = false;
			_left_button_down = false;
			_left_button_clicked = false;
		} else if (ev.button.button == SDL_BUTTON_LEFT) {
			_left_button_down = false;
			_left_button_clicked = false;
		} else if (ev.button.button == SDL_BUTTON_RIGHT) {
			_right_button_down = false;
		}
		break;

	case SDL_QUIT:
		// do not ask to quit on the main screen
		if (_game_mode != GM_MENU) {
			if(_patches.autosave_on_exit) {
				DoExitSave();
				return ML_QUIT;
			} else
				AskExitGame();
		} else
			return ML_QUIT;
		break;

		case SDL_KEYDOWN: /* Toggle full-screen on ALT + ENTER/F */
		if ((ev.key.keysym.mod & (KMOD_ALT | KMOD_META)) &&
				(ev.key.keysym.sym == SDLK_RETURN || ev.key.keysym.sym == SDLK_f)) {
			ToggleFullScreen(!_fullscreen);
		} else
			_pressed_key = ConvertSdlKeyIntoMy(&ev.key.keysym);

		break;

	case SDL_VIDEORESIZE: {
		int w = clamp(ev.resize.w, 64, MAX_SCREEN_WIDTH);
		int h = clamp(ev.resize.h, 64, MAX_SCREEN_HEIGHT);
		ChangeResInGame(w, h);
		break;
	}
	}
	return -1;
}

static const char *SdlVideoStart(const char * const *parm)
{
	char buf[30];

	const char *s = SdlOpen(SDL_INIT_VIDEO);
	if (s != NULL) return s;

	SDL_CALL SDL_VideoDriverName(buf, 30);
	DEBUG(misc, 1) ("sdl: using driver '%s'", buf);

	GetVideoModes();
	CreateMainSurface(_cur_resolution[0], _cur_resolution[1]);
	MarkWholeScreenDirty();

	SDL_CALL SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
	SDL_CALL SDL_EnableUNICODE(1);
	return NULL;
}

static void SdlVideoStop(void)
{
	SdlClose(SDL_INIT_VIDEO);
}

static int SdlVideoMainLoop(void)
{
	uint32 next_tick = SDL_CALL SDL_GetTicks() + 30;
	uint32 cur_ticks;
	uint32 pal_tick = 0;
	int i;
	uint32 mod;
	int numkeys;
	Uint8 *keys;

	for (;;) {
		InteractiveRandom(); // randomness

		while ((i = PollEvent()) == -1) {}
		if (i >= 0) return i;

		if (_exit_game) return ML_QUIT;

		mod = SDL_CALL SDL_GetModState();
		keys = SDL_CALL SDL_GetKeyState(&numkeys);
#if defined(_DEBUG)
		if (_shift_pressed)
#else
		if (keys[SDLK_TAB])
#endif
		{
			if (!_networking && _game_mode != GM_MENU) _fast_forward |= 2;
		} else if (_fast_forward & 2) {
			_fast_forward = 0;
		}

		cur_ticks = SDL_CALL SDL_GetTicks();
		if ((_fast_forward && !_pause) || cur_ticks > next_tick)
			next_tick = cur_ticks;

		if (cur_ticks == next_tick) {
			next_tick += 30;

			_ctrl_pressed = !!(mod & (KMOD_LCTRL | KMOD_RCTRL));
			_shift_pressed = !!(mod & (KMOD_LSHIFT | KMOD_RSHIFT));
			_dbg_screen_rect = !!(mod & KMOD_CAPS);

			// determine which directional keys are down
			_dirkeys =
				(keys[SDLK_LEFT]  ? 1 : 0) |
				(keys[SDLK_UP]    ? 2 : 0) |
				(keys[SDLK_RIGHT] ? 4 : 0) |
				(keys[SDLK_DOWN]  ? 8 : 0);
			GameLoop();

			_screen.dst_ptr = _sdl_screen->pixels;
			UpdateWindows();
			if (++pal_tick > 4) {
				CheckPaletteAnim();
				pal_tick = 1;
			}
			DrawSurfaceToScreen();
		} else {
			SDL_CALL SDL_Delay(1);
			_screen.dst_ptr = _sdl_screen->pixels;
			DrawTextMessage();
			DrawMouseCursor();
			DrawSurfaceToScreen();
		}
	}
}

static bool SdlVideoChangeRes(int w, int h)
{
	return CreateMainSurface(w, h);
}

static void SdlVideoFullScreen(bool full_screen)
{
	_fullscreen = full_screen;
	GetVideoModes(); // get the list of available video modes
	if (!_video_driver->change_resolution(_cur_resolution[0], _cur_resolution[1]))
		_fullscreen ^= true; // switching resolution failed, put back full_screen to original status
}

const HalVideoDriver _sdl_video_driver = {
	SdlVideoStart,
	SdlVideoStop,
	SdlVideoMakeDirty,
	SdlVideoMainLoop,
	SdlVideoChangeRes,
	SdlVideoFullScreen,
};

static void CDECL fill_sound_buffer(void *userdata, Uint8 *stream, int len)
{
	MxMixSamples(_mixer, stream, len / 4);
}

static const char *SdlSoundStart(const char * const *parm)
{
	SDL_AudioSpec spec;

	const char *s = SdlOpen(SDL_INIT_AUDIO);
	if (s != NULL) return s;

	spec.freq = GetDriverParamInt(parm, "hz", 11025);
	spec.format = AUDIO_S16SYS;
	spec.channels = 2;
	spec.samples = 512;
	spec.callback = fill_sound_buffer;
	SDL_CALL SDL_OpenAudio(&spec, &spec);
	SDL_CALL SDL_PauseAudio(0);
	return NULL;
}

static void SdlSoundStop(void)
{
	SDL_CALL SDL_CloseAudio();
	SdlClose(SDL_INIT_AUDIO);
}

const HalSoundDriver _sdl_sound_driver = {
	SdlSoundStart,
	SdlSoundStop,
};

#endif /* WITH_SDL */