text: // MIT License
  
  // Copyright (c) 2017 Vadim Grigoruk @nesbox
  
  // 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.
  
  #include <stdio.h>
  #include <SDL.h>
  #include <tic80.h>
  
  #define TIC80_WINDOW_SCALE 3
  
  static struct
  {
  	bool quit;
  } state =
  {
  	.quit = false,
  };
  
  static void onExit()
  {
  	state.quit = true;
  }
  
  s32 main(s32 argc, char **argv)
  {
  	char* cart = (argc > 1) ? argv[1] : "cart.tic";
  	FILE* file = fopen(cart, "rb");
  
  	if(file)
  	{
  		fseek(file, 0, SEEK_END);
  		s32 size = ftell(file);
  		fseek(file, 0, SEEK_SET);
  
  		void* cart = SDL_malloc(size);
  		if(cart) fread(cart, size, 1, file);
  		fclose(file);
  
  		if(cart)
  		{
  			SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO);
  
  			{
  				SDL_Window* window = SDL_CreateWindow("TIC-80 SDL demo", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, TIC80_FULLWIDTH * TIC80_WINDOW_SCALE, TIC80_FULLHEIGHT * TIC80_WINDOW_SCALE, SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE);
  				SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
  				SDL_Texture* texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ABGR8888, SDL_TEXTUREACCESS_STREAMING, TIC80_FULLWIDTH, TIC80_FULLHEIGHT);
  
  				SDL_AudioDeviceID audioDevice = 0;
  				SDL_AudioSpec audioSpec;
  				SDL_AudioCVT cvt;
  				bool audioStarted = false;
  
  				{
  					SDL_AudioSpec want =
  					{
  						.freq = TIC80_SAMPLERATE,
  						.format = AUDIO_S16,
  						.channels = 2,
  						.userdata = NULL,
  					};
  
  					audioDevice = SDL_OpenAudioDevice(NULL, 0, &want, &audioSpec, SDL_AUDIO_ALLOW_ANY_CHANGE);
  
  					SDL_BuildAudioCVT(&cvt, want.format, want.channels, audioSpec.freq, audioSpec.format, audioSpec.channels, audioSpec.freq);
  
  					if (cvt.needed)
  					{
  						cvt.len = audioSpec.freq * sizeof(s16) / TIC80_FRAMERATE;
  						cvt.buf = SDL_malloc(cvt.len * cvt.len_mult);
  					}
  				}
  
  				tic80_input input;
  				SDL_memset(&input, 0, sizeof input);
  
  				tic80* tic = tic80_create(audioSpec.freq);
  
  				tic->callback.exit = onExit;
  
  				tic80_load(tic, cart, size);
  
  				if(tic)
  				{
  					u64 nextTick = SDL_GetPerformanceCounter();
  					const u64 Delta = SDL_GetPerformanceFrequency() / TIC80_FRAMERATE;
  
  					while(!state.quit)
  					{
  						SDL_Event event;
  
  						while(SDL_PollEvent(&event))
  						{
  							switch(event.type)
  							{
  							case SDL_QUIT:
  								state.quit = true;
  								break;
  							}
  						}
  
  						{
  							input.gamepads.data = 0;
  							const uint8_t* keyboard = SDL_GetKeyboardState(NULL);
  
  							static const SDL_Scancode Keys[] =
  							{
  								SDL_SCANCODE_UP,
  								SDL_SCANCODE_DOWN,
  								SDL_SCANCODE_LEFT,
  								SDL_SCANCODE_RIGHT,
  
  								SDL_SCANCODE_Z,
  								SDL_SCANCODE_X,
  								SDL_SCANCODE_A,
  								SDL_SCANCODE_S,
  							};
  
  							for (s32 i = 0; i < SDL_arraysize(Keys); i++)
  							{
  								if (keyboard[Keys[i]])
  								{
  									input.gamepads.first.data |= (1 << i);
  								}
  							}
  						}
  
  						nextTick += Delta;
  
  						tic80_tick(tic, &input);
  
  						if (!audioStarted && audioDevice)
  						{
  							audioStarted = true;
  							SDL_PauseAudioDevice(audioDevice, 0);
  						}
  
  						{
  							SDL_PauseAudioDevice(audioDevice, 0);
  							s32 size = tic->sound.count * sizeof(tic->sound.samples[0]);
  
  							if (cvt.needed)
  							{
  								SDL_memcpy(cvt.buf, tic->sound.samples, size);
  								SDL_ConvertAudio(&cvt);
  								SDL_QueueAudio(audioDevice, cvt.buf, cvt.len_cvt);
  							}
  							else SDL_QueueAudio(audioDevice, tic->sound.samples, size);
  						}
  
  						SDL_RenderClear(renderer);
  
  						{
  							void* pixels = NULL;
  							s32 pitch = 0;
  							SDL_Rect destination;
  							SDL_LockTexture(texture, NULL, &pixels, &pitch);
  							SDL_memcpy(pixels, tic->screen, pitch * TIC80_FULLHEIGHT);
  							SDL_UnlockTexture(texture);
  
  							// Render the image in the proper aspect ratio.
  							{
  								s32 windowWidth, windowHeight;
  								SDL_GetWindowSize(window, &windowWidth, &windowHeight);
  								float widthRatio = (float)windowWidth / TIC80_FULLWIDTH;
  								float heightRatio = (float)windowHeight / TIC80_FULLHEIGHT;
  								float optimalSize = widthRatio < heightRatio ? widthRatio : heightRatio;
  								destination.w = (s32)(TIC80_FULLWIDTH * optimalSize);
  								destination.h = (s32)(TIC80_FULLHEIGHT * optimalSize);
  								destination.x = windowWidth / 2 - destination.w / 2;
  								destination.y = windowHeight / 2 - destination.h / 2;
  							}
  
  							SDL_RenderCopy(renderer, texture, NULL, &destination);
  						}
  
  						SDL_RenderPresent(renderer);
  
  						{
  							s64 delay = nextTick - SDL_GetPerformanceCounter();
  
  							if (delay < 0)
  								nextTick -= delay;
  							else SDL_Delay((u32)(delay * 1000 / SDL_GetPerformanceFrequency()));
  						}
  
  					}
  
  					tic80_delete(tic);
  				}
  
  				SDL_DestroyTexture(texture);
  				SDL_DestroyRenderer(renderer);
  				SDL_DestroyWindow(window);
  				SDL_CloseAudioDevice(audioDevice);
  			}
  
  			SDL_free(cart);
  		}
  	}
  
  	return 0;
  }
  