/* Copyright (C) 2025 Kasm Web
*
 * This is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this software; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 * USA.
 */

#include "benchmark.h"
#include <string>
#include <stdexcept>
#include <rfb/LogWriter.h>
#include "VNCServer.h"

static rfb::LogWriter vlog("Benchmarking");

void benchmark(const std::string &path) {
    AVFormatContext *format_ctx = nullptr;
    if (avformat_open_input(&format_ctx, path.c_str(), nullptr, nullptr) < 0)
        throw std::runtime_error("Could not open video file");

    FormatCtxGuard format_ctx_guard{format_ctx};

    // Find stream info
    if (avformat_find_stream_info(format_ctx, nullptr) < 0)
        throw std::runtime_error("Could not find stream info");

    // Find video stream
    int video_stream_idx = -1;
    for (uint32_t i = 0; i < format_ctx->nb_streams; ++i) {
        if (format_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
            video_stream_idx = static_cast<int>(i);
            break;
        }
    }

    if (video_stream_idx == -1)
        throw std::runtime_error("No video stream found");

    // Get codec parameters and decoder
    const auto *codec_parameters = format_ctx->streams[video_stream_idx]->codecpar;
    const auto *codec = avcodec_find_decoder(codec_parameters->codec_id);
    if (!codec)
        throw std::runtime_error("Codec not found");

    CodecCtxGuard codex_ctx_guard{avcodec_alloc_context3(codec)};
    auto *codec_ctx = codex_ctx_guard.get();

    if (!codec_ctx || avcodec_parameters_to_context(codec_ctx, codec_parameters) < 0)
        throw std::runtime_error("Failed to set up codec context");

    if (avcodec_open2(codec_ctx, codec, nullptr) < 0)
        throw std::runtime_error("Could not open codec");

    // Allocate frame and packet
    FrameGuard frame_guard{av_frame_alloc()};
    auto *frame = frame_guard.get();

    PacketGuard packet_guard{av_packet_alloc()};
    auto *packet = packet_guard.get();

    if (!frame || !packet)
        throw std::runtime_error("Could not allocate frame or packet");

    // Scaling context to convert to RGB24
    SwsContext *sws_ctx = sws_getContext(
        codec_ctx->width, codec_ctx->height, codec_ctx->pix_fmt,
        codec_ctx->width, codec_ctx->height, AV_PIX_FMT_RGB24,
        SWS_BILINEAR, nullptr, nullptr, nullptr
    );

    if (!sws_ctx)
        throw std::runtime_error("Could not create scaling context");

    SwsContextGuard sws_ctx_guard{sws_ctx};

    FrameGuard rgb_frame_guard{av_frame_alloc()};
    auto *rgb_frame = rgb_frame_guard.get();

    if (!rgb_frame)
        throw std::runtime_error("Could not allocate frame");

    rgb_frame->format = AV_PIX_FMT_RGB24;
    rgb_frame->width = codec_ctx->width;
    rgb_frame->height = codec_ctx->height;

    static const rfb::PixelFormat pf{32, 24, false, true, 0xFF, 0xFF, 0xFF, 0, 8, 16};
    const rfb::Rect rect{0, 0, rgb_frame->width, rgb_frame->height};

    rfb::ManagedPixelBuffer pb{pf, rect.width(), rect.height()};

    server->setPixelBuffer(&pb);

    if (av_frame_get_buffer(rgb_frame, 0) != 0)
        throw std::runtime_error("Could not allocate frame data");

    while (av_read_frame(format_ctx, packet) == 0) {
        if (packet->stream_index == video_stream_idx) {
            if (avcodec_send_packet(codec_ctx, packet) == 0) {
                while (avcodec_receive_frame(codec_ctx, frame) == 0) {
                    // Convert to RGB
                    sws_scale(sws_ctx, frame->data, frame->linesize, 0, frame->height,
                              rgb_frame->data, rgb_frame->linesize);


                    pb.imageRect(rect, rgb_frame->data[0], rect.width());
                }
            }
        }
        av_packet_unref(packet);
    }
}