#include "../rev.h"

#include "../blitter/factory.hpp"

#include "../network/network.h"

#include "../thread.h"

#include "../progress.h"

#include "../core/random_func.hpp"

#include "../core/math_func.hpp"

#include "../fileio_func.h"

#include "../framerate_type.h"

#include "../window_func.h"

#include "sdl2_v.h"

#include <SDL.h>

#include <mutex>

#include <condition_variable>

#ifdef __EMSCRIPTEN__

#	include <emscripten.h>

#	include <emscripten/html5.h>

#endif

#include "../safeguards.h"

static FVideoDriver_SDL iFVideoDriver_SDL;

static SDL_Window *_sdl_window;

static SDL_Surface *_sdl_surface;

static SDL_Surface *_sdl_rgb_surface;

static SDL_Surface *_sdl_real_surface;

/** Whether the drawing is/may be done in a separate thread. */

static bool _draw_threaded;

/** Mutex to keep the access to the shared memory controlled. */

static std::recursive_mutex *_draw_mutex = nullptr;

/** Signal to draw the next frame. */

static std::condition_variable_any *_draw_signal = nullptr;

/** Should we keep continue drawing? */

static volatile bool _draw_continue;

static Palette _local_palette;

static SDL_Palette *_sdl_palette;

#ifdef __EMSCRIPTEN__

/** Whether we just had a window-enter event. */

static bool _cursor_new_in_window = false;

#endif

#define MAX_DIRTY_RECTS 100

static SDL_Rect _dirty_rects[MAX_DIRTY_RECTS];

static int _num_dirty_rects;

void VideoDriver_SDL::MakeDirty(int left, int top, int width, int 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 void UpdatePalette()

{

	SDL_Color pal[256];

	for (int i = 0; i != _local_palette.count_dirty; i++) {

		pal[i].r = _local_palette.palette[_local_palette.first_dirty + i].r;

		pal[i].g = _local_palette.palette[_local_palette.first_dirty + i].g;

		pal[i].b = _local_palette.palette[_local_palette.first_dirty + i].b;

		pal[i].a = 0;

	}

	SDL_SetPaletteColors(_sdl_palette, pal, _local_palette.first_dirty, _local_palette.count_dirty);

	SDL_SetSurfacePalette(_sdl_surface, _sdl_palette);

}

static void MakePalette()

{

	if (_sdl_palette == nullptr) {

		_sdl_palette = SDL_AllocPalette(256);

		if (_sdl_palette == nullptr) usererror("SDL2: Couldn't allocate palette: %s", SDL_GetError());

	}

	_cur_palette.first_dirty = 0;

	_cur_palette.count_dirty = 256;

	_local_palette = _cur_palette;

	UpdatePalette();

	if (_sdl_surface != _sdl_real_surface) {

		/* When using a shadow surface, also set our palette on the real screen. This lets SDL

		 * allocate as many colors (or approximations) as

		 * possible, instead of using only the default SDL

		 * palette. This allows us to get more colors exactly

		 * right and might allow using better approximations for

		 * other colors.

		 *

		 * Note that colors allocations are tried in-order, so

		 * this favors colors further up into the palette. Also

		LoopOnce();

	}

	MainLoopCleanup();

#endif

}

void VideoDriver_SDL::MainLoopCleanup()

{

	if (_draw_mutex != nullptr) {

		_draw_continue = false;

		/* Sending signal if there is no thread blocked

		 * is very valid and results in noop */

		_draw_signal->notify_one();

		if (draw_lock.owns_lock()) draw_lock.unlock();

		draw_lock.release();

		draw_thread.join();

		delete _draw_mutex;

		delete _draw_signal;

		_draw_mutex = nullptr;

		_draw_signal = nullptr;

	}

#ifdef __EMSCRIPTEN__

	emscripten_exit_pointerlock();

	/* In effect, the game ends here. As emscripten_set_main_loop() caused

	 * the stack to be unwound, the code after MainLoop() in

	 * openttd_main() is never executed. */

	EM_ASM(if (window["openttd_syncfs"]) openttd_syncfs());

	EM_ASM(if (window["openttd_exit"]) openttd_exit());

#endif

}

bool VideoDriver_SDL::ChangeResolution(int w, int h)

{

	std::unique_lock<std::recursive_mutex> lock;

	if (_draw_mutex != nullptr) lock = std::unique_lock<std::recursive_mutex>(*_draw_mutex);

	return CreateMainSurface(w, h, true);

}

bool VideoDriver_SDL::ToggleFullscreen(bool fullscreen)

{

	std::unique_lock<std::recursive_mutex> lock;

	if (_draw_mutex != nullptr) lock = std::unique_lock<std::recursive_mutex>(*_draw_mutex);

	/* Remember current window size */

	if (fullscreen) {

		/* Find fullscreen window size */

		SDL_DisplayMode dm;

		if (SDL_GetCurrentDisplayMode(0, &dm) < 0) {

			DEBUG(driver, 0, "SDL_GetCurrentDisplayMode() failed: %s", SDL_GetError());

		} else {

			SDL_SetWindowSize(_sdl_window, dm.w, dm.h);

		}

	}

	DEBUG(driver, 1, "SDL2: Setting %s", fullscreen ? "fullscreen" : "windowed");

	int ret = SDL_SetWindowFullscreen(_sdl_window, fullscreen ? SDL_WINDOW_FULLSCREEN : 0);

	if (ret == 0) {

		/* Switching resolution succeeded, set fullscreen value of window. */

		_fullscreen = fullscreen;

	} else {

		DEBUG(driver, 0, "SDL_SetWindowFullscreen() failed: %s", SDL_GetError());

	}

	return ret == 0;

}

bool VideoDriver_SDL::AfterBlitterChange()

{

	assert(BlitterFactory::GetCurrentBlitter()->GetScreenDepth() != 0);

	int w, h;

	SDL_GetWindowSize(_sdl_window, &w, &h);

	return CreateMainSurface(w, h, false);

}

void VideoDriver_SDL::AcquireBlitterLock()

{

	if (_draw_mutex != nullptr) _draw_mutex->lock();

}

void VideoDriver_SDL::ReleaseBlitterLock()

{

	if (_draw_mutex != nullptr) _draw_mutex->unlock();

}

Dimension VideoDriver_SDL::GetScreenSize() const

{

	SDL_DisplayMode mode;

	if (SDL_GetCurrentDisplayMode(this->startup_display, &mode) != 0) return VideoDriver::GetScreenSize();

	return { static_cast<uint>(mode.w), static_cast<uint>(mode.h) };

}