/* Licensing information can be found at the end of the file. */
#include "lzr.h"
#include <SDL2/SDL.h>
#ifdef LZR_ENABLE_GFX
#	include <SDL2/SDL2_gfxPrimitives.h>
#endif
#ifdef LZR_ENABLE_IMAGE
#	include <SDL2/SDL_image.h>
#endif
#ifdef LZR_ENABLE_MIXER
#	include <SDL2/SDL_mixer.h>
#endif
#ifdef LZR_ENABLE_DEVMODE
#	include <sys/stat.h>
#endif
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>

#define UNPACKED_COLOR      color[0], color[1], color[2]
#define UNPACKED_COLOR_RGBA color[0], color[1], color[2], color[3]
#define SCODE_BIND_MENU     SDL_SCANCODE_F1
#define SCODE_FULLSCREEN    SDL_SCANCODE_F11

static LZR_Config config = {0};
static char *basepath = NULL;
static SDL_Window *window = NULL;
static SDL_Renderer *renderer = NULL;
static SDL_Texture *target = NULL;
static uint_least64_t next_time = 0;
static uint_least64_t min_dt = 0;
static bool should_quit = false;
static struct {
	SDL_Texture *tex;
	int width, height;
	char *path;
	long mtime;
} images[LZR_MAX_IMAGES] = {0};
static unsigned int color[4] = {0};
static unsigned int map[LZR_BUTTON_COUNT] = {
    SDL_SCANCODE_LEFT, SDL_SCANCODE_RIGHT, SDL_SCANCODE_UP,
    SDL_SCANCODE_DOWN, SDL_SCANCODE_X,     SDL_SCANCODE_C};
static bool input[LZR_BUTTON_COUNT] = {false};
static SDL_Point *points = NULL;
static uint64_t tick = 0;
static int off_x = 0;
static int off_y = 0;
static float scale = 1.0;
static int mouse_x = 0;
static int mouse_y = 0;

#ifdef LZR_ENABLE_MIXER
static struct {
	Mix_Chunk *ptr;
} sounds[LZR_MAX_SOUNDS] = {0};
static Mix_Music *music = NULL;
#endif

static char *_lzrstrdup(const char *str)
{
	char *const cpy = malloc(strlen(str) + 1);
	if (cpy == NULL)
		return NULL;
	strcpy(cpy, str);
	return cpy;
}

static int _scode_to_button(unsigned int scode)
{
	for (int i = 0; i < LZR_BUTTON_MOUSE_L; i++)
		if (map[i] == scode)
			return i;
	return -1;
}

static void _draw_btn(SDL_Renderer *ren, int btn, int x, int y,
                      unsigned int size)
{
#ifdef LZR_ENABLE_GFX
	const unsigned int size_2thirds = size * 2 / 3;
	switch (btn) {
	case LZR_BUTTON_LEFT:
		filledTrigonRGBA(ren, x - size / 2, y, x + size / 2,
		                 y + size_2thirds, x + size / 2,
		                 y - size_2thirds, 0, 0, 0, 255);
		break;
	case LZR_BUTTON_RIGHT:
		filledTrigonRGBA(ren, x + size / 2, y, x - size / 2,
		                 y + size_2thirds, x - size / 2,
		                 y - size_2thirds, 0, 0, 0, 255);
		break;
	case LZR_BUTTON_UP:
		filledTrigonRGBA(ren, x, y - size / 2, x - size_2thirds,
		                 y + size / 2, x + size_2thirds, y + size / 2,
		                 0, 0, 0, 255);
		break;
	case LZR_BUTTON_DOWN:
		filledTrigonRGBA(ren, x, y + size / 2, x - size_2thirds,
		                 y - size / 2, x + size_2thirds, y - size / 2,
		                 0, 0, 0, 255);
		break;
	case LZR_BUTTON_O:
		filledCircleRGBA(ren, x, y, size * 2 / 3, 0, 0, 0, 255);
		break;
	case LZR_BUTTON_X:
		thickLineRGBA(ren, x - size / 2, y - size / 2, x + size / 2,
		              y + size / 2, size / 16 + 1, 0, 0, 0, 255);
		thickLineRGBA(ren, x + size / 2, y - size / 2, x - size / 2,
		              y + size / 2, size / 16 + 1, 0, 0, 0, 255);
		break;
	default:
		break;
	}
#else
	(void)ren, (void)btn, (void)x, (void)y, (void)size;
#endif
}

static void _bind_menu(void)
{
	SDL_Log("entering bind menu");
	SDL_Window *win = NULL;
	SDL_Renderer *ren = NULL;
	if (SDL_CreateWindowAndRenderer(256, 256, 0, &win, &ren) < 0) {
		SDL_Log("%s", SDL_GetError());
		return;
	}
	int btn = 0;
	SDL_Event e;
	while (btn < LZR_BUTTON_MOUSE_L) {
		while (SDL_PollEvent(&e)) {
			if (e.type != SDL_KEYDOWN || e.key.repeat ||
			    e.key.keysym.scancode == SCODE_BIND_MENU ||
			    e.key.keysym.scancode == SCODE_FULLSCREEN)
				continue;
			if (e.key.keysym.scancode == SDL_SCANCODE_ESCAPE ||
			    e.type == SDL_QUIT)
				goto exit_bind_menu;
			LZR_ButtonBind(btn, e.key.keysym.scancode);
			btn++;
		}
		SDL_SetRenderDrawColor(ren, 220, 220, 200, 255);
		SDL_RenderClear(ren);
		SDL_SetRenderDrawColor(ren, 0, 0, 0, 255);
		_draw_btn(ren, btn, 128, 128, 104);
		SDL_RenderPresent(ren);
		sleep(0);
	}
exit_bind_menu:
	SDL_DestroyRenderer(ren);
	SDL_DestroyWindow(win);
	SDL_Log("leaving bind menu");
}

int LZR_Init(LZR_Config cfg)
{
	memcpy(&config, &cfg, sizeof(config));
	if (config.display_width == 0) {
		SDL_Log("display_width can't be 0");
		return -1;
	}
	if (config.display_height == 0) {
		SDL_Log("display_height can't be 0");
		return -1;
	}
	if (config.title == NULL) {
		SDL_Log("title is NULL, defaulting to 'LZR'");
		config.title = "LZR";
	}
	if (config.tile_size == 0)
		config.tile_size = 1;
	if (config.ratio <= 0.0)
		config.ratio = 1.0;
	else {
		const double ratio =
		    (float)config.display_width / (float)config.display_height;
		config.ratio /= ratio;
	}
	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
#ifdef LZR_ENABLE_IMAGE
	if (IMG_Init(IMG_INIT_PNG) != IMG_INIT_PNG) {
		SDL_Log("%s", IMG_GetError());
		return -1;
	}
#endif
#ifdef LZR_ENABLE_MIXER
	if (Mix_Init(MIX_INIT_FLAC) != MIX_INIT_FLAC) {
		SDL_Log("%s", Mix_GetError());
		return -1;
	}
	if (Mix_OpenAudio(44100, MIX_DEFAULT_FORMAT, 8, 1024) < 0) {
		SDL_Log("%s", Mix_GetError());
		return -1;
	}
#endif
	basepath = SDL_GetBasePath();
	if (basepath == NULL) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	const int dwidth = config.display_width * config.ratio;
	window = SDL_CreateWindow(config.title, SDL_WINDOWPOS_UNDEFINED,
	                          SDL_WINDOWPOS_UNDEFINED, dwidth,
	                          config.display_height, SDL_WINDOW_RESIZABLE);
	if (window == NULL) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
	if (renderer == NULL) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	target = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGB888,
	                           SDL_TEXTUREACCESS_TARGET,
	                           config.display_width, config.display_height);
	if (target == NULL) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	points =
	    calloc(cfg.display_width * cfg.display_height, sizeof(SDL_Point));
	if (points == NULL) {
		SDL_Log("calloc failed");
		return -1;
	}
	SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, 0);
	if (config.target_fps) {
		min_dt = 1000 / config.target_fps;
		next_time = SDL_GetTicks64();
	}
	if (config.hide_cursor && SDL_ShowCursor(SDL_DISABLE) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (LZR_DrawSetColor(1.0f, 1.0f, 1.0f, 1.0f))
		return -1;
	return 0;
}

void LZR_Quit(void)
{
#ifdef LZR_ENABLE_MIXER
	for (int i = 0; i < LZR_MAX_SOUNDS; i--)
		if (sounds[i].ptr != NULL) {
			Mix_FreeChunk(sounds[i].ptr);
			sounds[i].ptr = NULL;
		}
	Mix_CloseAudio();
	Mix_Quit();
#endif
	for (int i = 0; i < LZR_MAX_IMAGES; i++) {
		if (images[i].tex != NULL) {
			SDL_DestroyTexture(images[i].tex);
			images[i].tex = NULL;
		}
		if (images[i].path != NULL) {
			free(images[i].path);
			images[i].path = NULL;
		}
	}
	if (points != NULL) {
		free(points);
		points = NULL;
	}
	if (target != NULL) {
		SDL_DestroyTexture(target);
		target = NULL;
	}
	if (renderer != NULL) {
		SDL_DestroyRenderer(renderer);
		renderer = NULL;
	}
	if (window != NULL) {
		SDL_DestroyWindow(window);
		window = NULL;
	}
	if (basepath != NULL) {
		SDL_free(basepath);
		basepath = NULL;
	}
#ifdef LZR_ENABLE_IMAGE
	IMG_Quit();
#endif
	SDL_Quit();
}

bool LZR_ShouldQuit(void)
{
	return should_quit;
}

char *LZR_PathPrefix(const char *path)
{
	if (path == NULL) {
		SDL_Log("path is NULL");
		return NULL;
	}
	if (basepath == NULL) {
		SDL_Log("basepath is NULL");
		return _lzrstrdup(path);
	}
	char *const buf = malloc(strlen(basepath) + strlen(path) + 1);
	if (buf == NULL) {
		SDL_Log("malloc failed");
		return NULL;
	}
	strcpy(buf, basepath);
	strcat(buf, path);
	return buf;
}

int LZR_ImageLoad(const char *path)
{
	char *apath;
	long mtime = 0;
#ifdef LZR_ENABLE_DEVMODE
	apath = LZR_PathPrefix(path);
	if (apath == NULL)
		return -1;
	struct stat st = {0};
	(void)stat(apath, &st); /* stat can fail safely */
	mtime = st.st_mtim.tv_nsec;
#endif
	int i;
	for (i = 0; i < LZR_MAX_IMAGES; i++) {
		if (images[i].path != NULL &&
		    strcmp(images[i].path, path) == 0) {
			if (mtime != images[i].mtime) {
				SDL_Log("reloading %d", i);
				break;
			}
			return i;
		}
		if (images[i].tex == NULL)
			break;
	}
	if (i >= LZR_MAX_IMAGES) {
		SDL_Log("reached image limit (%d)", LZR_MAX_IMAGES);
		return -1;
	}
	apath = LZR_PathPrefix(path);
	if (apath == NULL) {
		SDL_Log("LZR_PathPrefix failed");
		return -1;
	}
#ifdef LZR_ENABLE_IMAGE
	SDL_Surface *const surf = IMG_Load(apath);
#else
	SDL_Surface *const surf = SDL_LoadBMP(apath);
#endif
	free(apath);
	if (surf == NULL) {
		SDL_Log("%s: %s", path, SDL_GetError());
		return -1;
	}
	SDL_Texture *const tex = SDL_CreateTextureFromSurface(renderer, surf);
	SDL_FreeSurface(surf);
	if (tex == NULL) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (images[i].tex != NULL)
		SDL_DestroyTexture(images[i].tex);
	images[i].tex = tex;
	images[i].mtime = mtime;
	if (SDL_SetTextureBlendMode(images[i].tex, SDL_BLENDMODE_BLEND) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (SDL_QueryTexture(tex, NULL, NULL, &images[i].width,
	                     &images[i].height)) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (images[i].path == NULL)
		images[i].path = _lzrstrdup(path);
	return i;
}

int LZR_SoundLoad(const char *path, float volume)
{
#ifdef LZR_ENABLE_MIXER
	int i;
	for (i = 0; i < LZR_MAX_SOUNDS; i++)
		if (sounds[i].ptr == NULL)
			break;
	if (i >= LZR_MAX_SOUNDS) {
		SDL_Log("reached sounds limit (%d)", LZR_MAX_SOUNDS);
		return -1;
	}
	char *const apath = LZR_PathPrefix(path);
	if (apath == NULL) {
		SDL_Log("LZR_PathPrefix failed");
		return -1;
	}
	Mix_Chunk *const chunk = Mix_LoadWAV(apath);
	free(apath);
	if (chunk == NULL) {
		SDL_Log("%s: %s", path, Mix_GetError());
		return -1;
	}
	Mix_VolumeChunk(chunk, volume);
	sounds[i].ptr = chunk;
	return i;
#else
	(void)path, (void)volume;
	return -1;
#endif
}

bool LZR_PollEvent(LZR_Event *e)
{
	if (e == NULL) {
		SDL_Log("e is NULL");
		return false;
	}
	SDL_Event se;
	while (SDL_PollEvent(&se)) {
		switch (se.type) {
		case SDL_QUIT:
			e->type = LZR_EVENT_QUIT;
			should_quit = true;
			return true;
		case SDL_KEYDOWN: {
			if (!config.disable_bind_menu &&
			    se.key.keysym.scancode == SCODE_BIND_MENU)
				_bind_menu();
			if (se.key.keysym.scancode == SCODE_FULLSCREEN)
				LZR_ToggleFullscreen();
			const int b = _scode_to_button(se.key.keysym.scancode);
			if (se.key.repeat || b < 0)
				break;
			e->type = LZR_EVENT_BUTTON_DOWN;
			e->button = b;
			input[b] = true;
			return true;
		}
		case SDL_MOUSEBUTTONDOWN: {
			e->type = LZR_EVENT_BUTTON_DOWN;
			e->button = LZR_BUTTON_MOUSE_L + se.button.button - 1;
			e->x = se.button.x, e->y = se.button.y;
			LZR_ScreenTransform(&e->x, &e->y);
			mouse_x = e->x, mouse_y = e->y;
			if (e->button >= LZR_BUTTON_COUNT)
				continue;
			input[e->button] = true;
			return true;
		}
		case SDL_KEYUP: {
			const int b = _scode_to_button(se.key.keysym.scancode);
			if (b < 0)
				break;
			e->type = LZR_EVENT_BUTTON_UP;
			e->button = b;
			input[b] = false;
			return true;
		}
		case SDL_MOUSEBUTTONUP: {
			e->type = LZR_EVENT_BUTTON_DOWN;
			e->button = LZR_BUTTON_MOUSE_L + se.button.button - 1;
			e->x = se.button.x, e->y = se.button.y;
			LZR_ScreenTransform(&e->x, &e->y);
			mouse_x = e->x, mouse_y = e->y;
			if (e->button >= LZR_BUTTON_COUNT)
				continue;
			input[e->button] = false;
			return true;
		}
		case SDL_MOUSEMOTION: {
			e->type = LZR_EVENT_MOUSE_MOVE;
			e->x = se.motion.x, e->y = se.motion.y;
			LZR_ScreenTransform(&e->x, &e->y);
			mouse_x = e->x, mouse_y = e->y;
			return true;
		}
		default:
			break;
		}
	}
	return false;
}

void LZR_CycleEvents(void)
{
	LZR_Event e;
	while (LZR_PollEvent(&e))
		;
}

bool LZR_ButtonDown(LZR_Button btn)
{
	if (btn >= 0 && btn < LZR_BUTTON_COUNT)
		return input[btn];
	else
		SDL_Log("%d button doesn't exist", btn);
	return false;
}

void LZR_ButtonBind(LZR_Button btn, unsigned int code)
{
	if (btn < LZR_BUTTON_MOUSE_L && code != SCODE_BIND_MENU) {
		map[btn] = code;
		SDL_Log("bound key %s to button %u",
		        SDL_GetScancodeName(map[btn]), btn);
	} else
		SDL_Log("button %u can't be remapped to key %s", btn,
		        SDL_GetScancodeName(code));
}

int LZR_DrawBegin(void)
{
	if (config.target_fps > 0)
		next_time += min_dt;
	if (SDL_SetRenderTarget(renderer, target) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
	SDL_RenderClear(renderer);
	return 0;
}

int LZR_DrawEnd(void)
{
	if (SDL_SetRenderTarget(renderer, NULL)) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	LZR_DrawSetColor(0.0f, 0.0f, 0.0f, 1.0f);
	if (LZR_DrawClear()) {
		SDL_Log("LZY_DrawClear failed");
		return -1;
	}
	if (config.target_fps) {
		const uint_least64_t cur_time = SDL_GetTicks64();
		if (next_time <= cur_time)
			next_time = cur_time;
		else
			SDL_Delay(next_time - cur_time);
	}
	int win_w, win_h;
	SDL_GetWindowSize(window, &win_w, &win_h);
	const int width = config.display_width * config.ratio;
	const int height = config.display_height;
	const int ratio_w = win_w / width;
	const int ratio_h = win_h / height;
	scale = (ratio_w <= ratio_h) ? ratio_w : ratio_h;
	off_x = (win_w - width * scale) / 2;
	off_y = (win_h - height * scale) / 2;
	const SDL_Rect dest = {off_x, off_y, width * scale, height * scale};
	if (SDL_RenderCopyEx(renderer, target, NULL, &dest, 0.0, NULL, 0) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	SDL_RenderPresent(renderer);
	tick++;
	return 0;
}

int LZR_DrawSetColor(float r, float g, float b, float a)
{
	const unsigned int ur = (unsigned int)(r * 255) & 255;
	const unsigned int ug = (unsigned int)(g * 255) & 255;
	const unsigned int ub = (unsigned int)(b * 255) & 255;
	const unsigned int ua = (unsigned int)(a * 255) & 255;
	if (SDL_SetRenderDrawColor(renderer, ur, ug, ub, ua) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	color[0] = ur, color[1] = ug, color[2] = ub, color[3] = ua;
	return 0;
}

int LZR_DrawClear(void)
{
	if (SDL_RenderClear(renderer) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawPoint(int x, int y)
{
	if (SDL_RenderDrawPoint(renderer, x, y) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawPoints(int *x, int *y, int n)
{

	if (n > (int)(config.display_width * config.display_height)) {
		SDL_Log("%d > %u", n,
		        config.display_width * config.display_height);
		return -1;
	}
	for (int i = 0; i < n; i++) {
		points[i].x = x[i];
		points[i].y = y[i];
	}
	if (SDL_RenderDrawPoints(renderer, points, n) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawLine(int x0, int y0, int x1, int y1)
{
	if (SDL_RenderDrawLine(renderer, x0, y0, x1, y1) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawRectangle(bool fill, int x, int y, int w, int h)
{
	SDL_Rect rect = {x, y, w, h};
	if ((fill ? SDL_RenderFillRect : SDL_RenderDrawRect)(renderer, &rect)) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawCircle(bool fill, int x, int y, int radius)
{
#ifdef LZR_ENABLE_GFX
	if ((fill ? filledCircleRGBA : circleRGBA)(renderer, x, y, radius,
	                                           UNPACKED_COLOR_RGBA) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
#else
	(void)fill, (void)x, (void)y, (void)radius;
	SDL_Log("LZR GFX module is disabled");
	return -1;
#endif
}

int LZR_DrawPolygon(bool fill, int *vx, int *vy, int n)
{
#ifdef LZR_ENABLE_GFX
	if (n > 32) {
		SDL_Log("%d > 32", n);
		return -1;
	}
	Sint16 x[32], y[32];
	for (int i = 0; i < n; i++)
		x[i] = vx[i], y[i] = vy[i];
	if ((fill ? filledPolygonRGBA : polygonRGBA)(renderer, x, y, n,
	                                             UNPACKED_COLOR_RGBA) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
#else
	(void)fill, (void)vx, (void)vy, (void)n;
	SDL_Log("LZR GFX module is disabled");
	return -1;
#endif
}

int LZR_DrawImage(int id, int x, int y)
{
	if (id < 0) {
		SDL_Log("id is negative");
		return -1;
	}
	if (id >= LZR_MAX_IMAGES || images[id].tex == NULL) {
		SDL_Log("no image with id %d", id);
		return -1;
	}
	if (SDL_SetTextureColorMod(images[id].tex, UNPACKED_COLOR) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (SDL_SetTextureAlphaMod(images[id].tex, color[3]) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	const SDL_Rect dest = {x, y, images[id].width, images[id].height};
	if (SDL_RenderCopy(renderer, images[id].tex, NULL, &dest) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawImageEx(int id, int x, int y, LZR_ImageDrawSettings stg)
{
	if (id < 0) {
		SDL_Log("id is negative");
		return -1;
	}
	if (id >= LZR_MAX_IMAGES || images[id].tex == NULL) {
		SDL_Log("no image with id %d", id);
		return -1;
	}
	const int width = (stg.width > 0) ? stg.width : images[id].width;
	const int height = (stg.height > 0) ? stg.height : images[id].height;
	if (stg.center) {
		x -= stg.scale_x * width / 2;
		y -= stg.scale_y * height / 2;
	}
	SDL_Rect src = {stg.ix, stg.iy, width, height};
	SDL_Rect dst = {x, y, width * stg.scale_x, height * stg.scale_y};
	if (stg.ix < 0) {
		src.w += stg.ix;
		dst.x = 0 - stg.ix;
		dst.w += stg.ix;
	}
	if (stg.iy < 0) {
		src.y = 0 - stg.iy;
		src.h += stg.iy;
		dst.y -= stg.iy;
		dst.h += stg.iy;
	}
	if (stg.ix + width > images[id].width) {
		src.w = images[id].width - stg.ix;
		dst.w = images[id].width - stg.ix;
	}
	if (stg.iy + height > images[id].height) {
		src.h = images[id].height - stg.iy;
		dst.h = images[id].height - stg.iy;
	}
	if (SDL_SetTextureColorMod(images[id].tex, UNPACKED_COLOR) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (SDL_SetTextureAlphaMod(images[id].tex, color[3]) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	const int flip = (stg.flip_v ? SDL_FLIP_VERTICAL : 0) |
	                 (stg.flip_h ? SDL_FLIP_HORIZONTAL : 0);
	if (SDL_RenderCopyEx(renderer, images[id].tex, &src, &dst,
	                     stg.angle * 360.0, NULL, flip)) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_DrawTile(int id, int tile, int x, int y, double rot, int flip)
{
	if (id < 0) {
		SDL_Log("id is negative");
		return -1;
	}
	if (id >= LZR_MAX_IMAGES || images[id].tex == NULL) {
		SDL_Log("no image with id %d", id);
		return -1;
	}
	if (tile < 0) {
		SDL_Log("tile is negative");
		return -1;
	}
	const int img_width = images[id].width / config.tile_size;
	const int img_height = images[id].height / config.tile_size;
	if (tile >= img_width * img_height) {
		SDL_Log("tile exceeds boundaries");
		return -1;
	}
	if (SDL_SetTextureColorMod(images[id].tex, UNPACKED_COLOR) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	if (SDL_SetTextureAlphaMod(images[id].tex, color[3]) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	SDL_Rect src;
	src.x = (tile % img_width) * config.tile_size;
	src.y = (tile / img_width) * config.tile_size;
	src.w = config.tile_size, src.h = config.tile_size;
	const SDL_Rect dst = {x, y, config.tile_size, config.tile_size};
	if (SDL_RenderCopyEx(renderer, images[id].tex, &src, &dst, rot, NULL,
	                     flip) < 0) {
		SDL_Log("%s", SDL_GetError());
		return -1;
	}
	return 0;
}

int LZR_PlaySound(int id)
{
#ifdef LZR_ENABLE_MIXER
	if (id < 0) {
		SDL_Log("id is negative");
		return -1;
	}
	if (id >= LZR_MAX_SOUNDS || sounds[id].ptr == NULL) {
		SDL_Log("no sound with id %d", id);
		return -1;
	}
	if (Mix_PlayChannel(-1, sounds[id].ptr, 0) < 0) {
		SDL_Log("%s", Mix_GetError());
		return -1;
	}
	return 0;
#else
	(void)id;
	SDL_Log("LZR MIXER module is disabled");
	return -1;
#endif
}

int LZR_SetMusicVolume(float volume)
{
#ifdef LZR_ENABLE_MIXER
	if (Mix_VolumeMusic(volume * MIX_MAX_VOLUME) < 0) {
		SDL_Log("%s", Mix_GetError());
		return -1;
	}
	return 0;
#else
	(void)volume;
	SDL_Log("LZR MIXER module is disabled");
	return -1;
#endif
}

int LZR_PlayMusic(const char *path, int loops)
{
#ifdef LZR_ENABLE_MIXER
	LZR_StopMusic();
	char *const apath = LZR_PathPrefix(path);
	if (apath == NULL) {
		SDL_Log("LZR_PathPrefix failed");
		return -1;
	}
	music = Mix_LoadMUS(apath);
	free(apath);
	if (music == NULL) {
		SDL_Log("%s: %s", path, Mix_GetError());
		return -1;
	}
	if (Mix_PlayMusic(music, loops) < 0) {
		SDL_Log("%s", Mix_GetError());
		return -1;
	}
	Mix_RewindMusic();
	return 0;
#else
	(void)path, (void)loops;
	SDL_Log("LZR MIXER module is disabled");
	return -1;
#endif
}

void LZR_StopMusic(void)
{
#ifdef LZR_ENABLE_MIXER
	if (Mix_PlayingMusic())
		Mix_HaltMusic();
	if (music != NULL) {
		Mix_FreeMusic(music);
		music = NULL;
	}
#endif
}

void LZR_ToggleFullscreen(void)
{
	static int fullscreen = 0;
	fullscreen = !fullscreen;
	SDL_SetWindowFullscreen(window,
	                        fullscreen * SDL_WINDOW_FULLSCREEN_DESKTOP);
}

uint64_t LZR_GetTick(void)
{
	return tick;
}

void LZR_ScreenTransform(int *x, int *y)
{
	if (scale == 0.0)
		return;
	if (x != NULL) {
		*x -= off_x;
		*x /= scale;
	}
	if (y != NULL) {
		*y -= off_y;
		*y /= scale;
	}
}

void LZR_MousePosition(int *x, int *y)
{
	if (x != NULL)
		*x = mouse_x;
	if (y != NULL)
		*y = mouse_y;
}

/*
** Copyright (c) 2022, 2023 kdx
**
** Permission is hereby granted, free of charge, to any person obtaining a copy
** of this software and associated documentation files (the "Software"), to
** deal in the Software without restriction, including without limitation the
** rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
** sell copies of the Software, and to permit persons to whom the Software is
** furnished to do so, subject to the following conditions:
**
** The above copyright notice and this permission notice shall be included in
** all copies or substantial portions of the Software.
**
** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
** IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
** FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
** AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
** FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
** IN THE SOFTWARE.
*/