#include "gui.h"
#include <stdbool.h>

#include <SDL.h>
#include <SDL_image.h>
#include <SDL_ttf.h>

const SCREEN_WIDTH = 800;
const SCREEN_HEIGHT = 920;

SDL_Window* window = NULL;
// SDL_Surface* screenSurface = NULL;
SDL_Renderer *window_renderer = NULL;
SDL_Texture* tile_texture = NULL;
SDL_Texture* tile_textures[13];
SDL_Rect tile_size;
SDL_Texture* game_over_texture = NULL;

SDL_Texture *texture_from_png(char *n) {
    SDL_Surface *s = IMG_Load(n);
    SDL_Texture *t = SDL_CreateTextureFromSurface( window_renderer, s);
    SDL_FreeSurface(s);
    return t;
}

void gui_init() {

    //Initialize SDL
    if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
    {
        printf( "SDL could not initialize! SDL_Error: %s\n", SDL_GetError() );
    }

    window = SDL_CreateWindow( "2048", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN );
    if( window == NULL )
    {
        printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
    }
    // screenSurface = SDL_GetWindowSurface(window);
    // SDL_FillRect(screenSurface, NULL, SDL_MapRGB(screenSurface->format, 255, 255, 255));


    // create renderer and render white window
    window_renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
    SDL_SetRenderDrawColor(window_renderer, 0xFF, 0xFF, 0xFF, 0xFF );
    SDL_RenderClear(window_renderer);
    SDL_RenderPresent(window_renderer);
    // SDL_UpdateWindowSurface(window);

    // load up textures
    tile_texture = texture_from_png("res/tile.png");
    tile_textures[0] = tile_texture;
    tile_textures[2] = texture_from_png("res/2.png");
    tile_textures[3] = texture_from_png("res/4.png");
    tile_textures[4] = texture_from_png("res/8.png");
    tile_textures[5] = texture_from_png("res/16.png");
    tile_textures[6] = texture_from_png("res/32.png");
    tile_textures[7] = texture_from_png("res/64.png");
    tile_textures[8] = texture_from_png("res/128.png");
    tile_textures[9] = texture_from_png("res/256.png");
    tile_textures[10] = texture_from_png("res/512.png");
    tile_textures[11] = texture_from_png("res/1024.png");
    tile_textures[12] = texture_from_png("res/2048.png");
    tile_size.x = 0;
    tile_size.y = 0;
    SDL_QueryTexture(tile_texture, NULL, NULL, &tile_size.w, &tile_size.h);

    game_over_texture = texture_from_png("res/game_over.png");
}

void gui_destroy() {
    //Destroy window
    SDL_DestroyWindow( window );
    SDL_DestroyRenderer(window_renderer);
    for (int i = 0; i < 13; i++) {
        SDL_DestroyTexture(tile_textures[i]);
    }
    SDL_DestroyTexture(game_over_texture);

    //Quit SDL subsystems
    SDL_Quit();

}

void gui_loop(Game *game) {
    bool quit = false;
    bool needs_redraw = true; // there's no need to redraw window when nothing's changed. will be set to false later. first run has to be always done
    SDL_Event e;

    while(!quit) {
        while( SDL_PollEvent( &e ) != 0 )
        {
            switch( e.type ) {
                /* Keyboard event */
                /* Pass the event data onto PrintKeyInfo() */
                case SDL_KEYDOWN:
                    switch (e.key.keysym.sym) {
                        case SDLK_h:
                        case SDLK_LEFT:
                        case SDLK_4:
                            needs_redraw = true;
                            game_move(game, Left);
                            break;
                        case SDLK_l:
                        case SDLK_RIGHT:
                        case SDLK_6:
                            needs_redraw = true;
                            game_move(game, Right);
                            break;
                        case SDLK_j:
                        case SDLK_DOWN:
                        case SDLK_2:
                            needs_redraw = true;
                            game_move(game, Down);
                            break;
                        case SDLK_k:
                        case SDLK_UP:
                        case SDLK_8:
                            needs_redraw = true;
                            game_move(game, Up);
                            break;
                    }
                    break;
                case SDL_QUIT:
                    quit = 1;
                    break;
            }
        }

        if (needs_redraw) {
            SDL_RenderClear(window_renderer);
            SDL_Rect tile_rect = tile_size;
            for (int i = 0; i < game->field_size_x; i++) {
                tile_rect.x = i * 175 + 50;
                for (int j = 0; j < game->field_size_y; j++) {
                    tile_rect.y = j * 175 + 150;
                    
                    // get texture index from  value
                    for (int k = 0; k < 13; k++) {
                        if (!(game->field[j][i] >> k)) {
                            SDL_RenderCopy( window_renderer, tile_textures[k], NULL, &tile_rect);
                            break;
                        }
                    }
                    // SDL_RenderCopy( window_renderer, tile_texture, NULL, &tile_rect);
                }
            }
            if (game->game_over) {
                // render game over screen
                SDL_RenderCopy(window_renderer, game_over_texture, NULL, NULL);
            }
            SDL_RenderPresent(window_renderer);
            needs_redraw = false;
        }
        
    }

}