#include "XCEngine/RHI/OpenGL/OpenGLScreenshot.h"
#include "XCEngine/RHI/OpenGL/OpenGLDevice.h"
#include "XCEngine/RHI/OpenGL/OpenGLSwapChain.h"
#include "XCEngine/Debug/Logger.h"
#include "XCEngine/Debug/ConsoleLogSink.h"
#include "XCEngine/Containers/String.h"

#include <glad/glad.h>

#include <cstdio>
#include <cstdlib>
#include <cstring>

using namespace XCEngine::Debug;

namespace XCEngine {
namespace RHI {
namespace {

bool SavePPM(const char* filename, int width, int height) {
    unsigned char* pixels = (unsigned char*)malloc(width * height * 3);
    if (!pixels) {
        Logger::Get().Error(LogCategory::Rendering, "[OpenGLScreenshot] Failed to allocate pixel buffer");
        return false;
    }

    glFinish();
    glReadBuffer(GL_BACK);
    glPixelStorei(GL_PACK_ALIGNMENT, 1);
    glPixelStorei(GL_PACK_ROW_LENGTH, 0);
    glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
    glPixelStorei(GL_PACK_SKIP_ROWS, 0);
    glReadPixels(0, 0, width, height, GL_RGB, GL_UNSIGNED_BYTE, pixels);

    FILE* f = fopen(filename, "wb");
    if (!f) {
        Logger::Get().Error(LogCategory::Rendering, "[OpenGLScreenshot] Failed to open file");
        free(pixels);
        return false;
    }

    fprintf(f, "P6\n%d %d\n255\n", width, height);

    unsigned char* row = (unsigned char*)malloc(width * 3);
    for (int y = height - 1; y >= 0; y--) {
        memcpy(row, pixels + y * width * 3, width * 3);
        fwrite(row, 1, width * 3, f);
    }

    free(row);
    free(pixels);
    fclose(f);

    Logger::Get().Debug(LogCategory::Rendering, "[OpenGLScreenshot] Screenshot saved");
    return true;
}

} // anonymous namespace

bool OpenGLScreenshot::Capture(OpenGLDevice& device, OpenGLSwapChain& swapChain, const char* filename) {
    return Capture(device, swapChain, filename, swapChain.GetWidth(), swapChain.GetHeight());
}

bool OpenGLScreenshot::Capture(OpenGLDevice& device, OpenGLSwapChain& swapChain, const char* filename, int width, int height) {
    (void)device;
    (void)swapChain;
    return SavePPM(filename, width, height);
}

} // namespace RHI
} // namespace XCEngine