/* SPDX-License-Identifier: Unlicense
 */

#include "graphics.hpp"
#include "vdp.hpp"

#include <cstdlib>

Graphics::Graphics()
{
#if HAS_GRAPHICS == 1
    SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);

    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
        return;
    }
    _window = SDL_CreateWindow("Gut (SEGA MD/G emulator)",
                              SDL_WINDOWPOS_UNDEFINED,
                              SDL_WINDOWPOS_UNDEFINED,
                              VDP().render_width, VDP().render_height,
                              SDL_WINDOW_RESIZABLE);
    if (!_window) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set create window: %s\n", SDL_GetError());
        SDL_Quit();
        return;
    }
    _renderer = SDL_CreateRenderer(_window, -1, 0);
    if (!_renderer) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set create renderer: %s\n", SDL_GetError());
        SDL_Quit();
        return;
    }
    _render_texture = SDL_CreateTexture(
            _renderer,
            SDL_PIXELFORMAT_ARGB8888,
            SDL_TEXTUREACCESS_STREAMING,
            VDP().render_width,
            VDP().render_height);
    if (!_render_texture) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set create texture: %s\n", SDL_GetError());
        SDL_Quit();
        return;
    }
#endif
    _initialized_ok = true;
}

Graphics::~Graphics()
{
#if HAS_GRAPHICS == 1
    SDL_DestroyTexture(_render_texture);
    SDL_DestroyRenderer(_renderer);
    SDL_DestroyWindow(_window);
    SDL_Quit();
#endif
}

void Graphics::Render(const VDP& vdp)
{
    const uint8_t* buffer = vdp.GetRenderedBuffer();
#if HAS_GRAPHICS == 1
    void* pixels;
    int pitch;
    if (SDL_LockTexture(_render_texture, NULL, &pixels, &pitch) < 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't lock texture: %s\n", SDL_GetError());
        abort();
    }
    for (int row = 0; (size_t)row < VDP().render_height; row++) {
        uint32_t *dst = (uint32_t*)((uint8_t*)pixels + row * pitch);
        for (int col = 0; (size_t)col < VDP().render_width; col++, buffer += 4) {
            const uint32_t color = ((buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]);
            *dst++ = color;
        }
    }
    SDL_UnlockTexture(_render_texture);
    SDL_RenderClear(_renderer);
    SDL_RenderCopy(_renderer, _render_texture, NULL, NULL);
    SDL_RenderPresent(_renderer);
#else
    (void) buffer;
#endif
}