#include <stdio.h>
#include <stdbool.h>
#include <unistd.h>
#include <assert.h>
#include <ctype.h>
#include <Core/gb.h>

#include "get_image_for_rom.h"

unsigned int duration = 60*10;

struct local_data {
    unsigned long frames;
    bool running;
};

static char *async_input_callback(GB_gameboy_t *gb)
{
    return NULL;
}

static void log_callback(GB_gameboy_t *gb, const char *string, GB_log_attributes attributes)
{

}


static void vblank(GB_gameboy_t *gb)
{

    struct local_data *local_data = (struct local_data *)GB_get_user_data(gb);

    if (local_data->frames == duration) {
        local_data->running = false;
    }
    else if (local_data->frames == duration - 1) {
        GB_set_rendering_disabled(gb, false);
    }

    local_data->frames++;
}

static uint32_t rgb_encode(GB_gameboy_t *gb, uint8_t r, uint8_t g, uint8_t b)
{
    return (b << 16) | (g << 8) | (r) | 0xFF000000;
}

int get_image_for_rom_common(GB_gameboy_t gb, const char *filename, uint32_t *output, uint8_t *cgb_flag) {
    GB_set_vblank_callback(&gb, (GB_vblank_callback_t) vblank);
    GB_set_pixels_output(&gb, output);
    GB_set_rgb_encode_callback(&gb, rgb_encode);
    GB_set_async_input_callback(&gb, async_input_callback);
    GB_set_log_callback(&gb, log_callback);
    GB_set_color_correction_mode(&gb, GB_COLOR_CORRECTION_EMULATE_HARDWARE);
    
    size_t length = strlen(filename);
    char extension[4] = {0,};
    if (length > 4) {
        if (filename[length - 4] == '.') {
            extension[0] = tolower(filename[length - 3]);
            extension[1] = tolower(filename[length - 2]);
            extension[2] = tolower(filename[length - 1]);
        }
    }
    if (strcmp(extension, "isx") == 0) {
        if (GB_load_isx(&gb, filename)) {
            GB_free(&gb);
            return 1;
        }
    }
    else if (GB_load_rom(&gb, filename)) {
        GB_free(&gb);
        return 1;
    }

    /* Run emulation */
    struct local_data local_data = {0,};
    GB_set_user_data(&gb, &local_data);
    local_data.running = true;
    local_data.frames = 0;
    GB_set_rendering_disabled(&gb, true);
    GB_set_turbo_mode(&gb, true, true);

    *cgb_flag = GB_read_memory(&gb, 0x143) & 0xC0;

    while (local_data.running) {
        GB_run(&gb);
    }

    GB_free(&gb);
    return 0;
}

int get_image_for_rom_alt(const char *filename, const unsigned char *buffer, size_t size, uint32_t *output, uint8_t *cgb_flag)
{
    GB_gameboy_t gb;
    GB_init(&gb, GB_MODEL_CGB_E);
    GB_load_boot_rom_from_buffer(&gb, buffer, size);

    return get_image_for_rom_common(gb, filename, output, cgb_flag);
}

int get_image_for_rom(const char *filename, const char *boot_path, uint32_t *output, uint8_t *cgb_flag)
{
    GB_gameboy_t gb;
    GB_init(&gb, GB_MODEL_CGB_E);
    if (GB_load_boot_rom(&gb, boot_path)) {
        GB_free(&gb);
        return 1;
    }

    return get_image_for_rom_common(gb, filename, output, cgb_flag);
}