/*
 * Copyright (c) 2023 Fancy Code.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include "FfmpegReadFile.h"
#include "FfmpegBase.h"
#include "ILog.h"
#include "MediaBase.h"
#include "StatusCode.h"
#include <cstdlib>
#include <string>
#ifdef __cplusplus
extern "C" {
#endif
#include <libavcodec/packet.h>
#include <libavformat/avformat.h>
#include <libavutil/avutil.h>
#include <libavutil/error.h>
#ifdef __cplusplus
}
#endif
#include <chrono>
#include <math.h>
#include <memory>
#include <thread>
FfmpegReadFile::FfmpegReadFile()
    : mReadVideoCallback(nullptr), mReadVideoCallbackContext(nullptr), mReadAudioCallback(nullptr),
      mReadAudioCallbackContext(nullptr)
{
}
StatusCode FfmpegReadFile::StartReadFile(const std::string &path)
{
    InitFfmpeg();
    int result = 0;
    const AVInputFormat *iformat = av_find_input_format(FfmpegBase::InputFormat(mType));
    AVFormatContext *pFormatCtx = nullptr;
    if ((result = avformat_open_input(&pFormatCtx, path.c_str(), iformat, nullptr)) < 0) {
        char error_str[AV_ERROR_MAX_STRING_SIZE] = {0};
        LogError("Couldn't open file: %s, result=%s\n",
                 path.c_str(),
                 av_make_error_string(error_str, AV_ERROR_MAX_STRING_SIZE, result));
        return CreateStatusCode(STATUS_CODE_NOT_OK);
    }
    if (avformat_find_stream_info(pFormatCtx, nullptr) < 0) {
        LogError("Couldn't find stream information.\n");
        avformat_close_input(&pFormatCtx);
        return CreateStatusCode(STATUS_CODE_NOT_OK);
    }
    int mediaStreamIndex = -1;
    for (unsigned int i = 0; i < pFormatCtx->nb_streams; i++) {
        if (pFormatCtx->streams[i]->codecpar->codec_type == mFFmpegMediaType) {
            mediaStreamIndex = i;
            break;
        }
    }
    if (mediaStreamIndex == -1) {
        LogError("Didn't find a stream.\n");
        avformat_close_input(&pFormatCtx);
        return CreateStatusCode(STATUS_CODE_NOT_OK);
    }
    auto taskTimerThread = [=](std::shared_ptr<FfmpegReadFile> media) {
        LogInfo("ReadFileThread start.\n");
        media->ReadFileThread(pFormatCtx, mediaStreamIndex);
    };
    std::shared_ptr<FfmpegReadFile> media = std::dynamic_pointer_cast<FfmpegReadFile>(FfmpegBase::shared_from_this());
    mTaskTimerThread = std::thread(taskTimerThread, media);
    return CreateStatusCode(STATUS_CODE_OK);
}
StatusCode FfmpegReadFile::StopReadFile(void)
{
    mTaskRuning = false;
    if (mTaskTimerThread.joinable()) {
        mTaskTimerThread.join();
    }
    return CreateStatusCode(STATUS_CODE_OK);
}
StatusCode FfmpegReadFile::SetReadVideoCallback(ReadVideoFileCallback callback, void *context)
{
    mReadVideoCallback = callback;
    mReadVideoCallbackContext = context;
    return CreateStatusCode(STATUS_CODE_OK);
}
StatusCode FfmpegReadFile::SetReadAudioCallback(ReadVideoFileCallback callback, void *context)
{
    mReadAudioCallback = callback;
    mReadAudioCallbackContext = context;
    return CreateStatusCode(STATUS_CODE_OK);
}
void FfmpegReadFile::ReadFileThread(AVFormatContext *pFormatCtx, int mediaStreamIndex)
{
    mTaskRuning = true;
    if (AVMEDIA_TYPE_VIDEO == mFFmpegMediaType && nullptr == mReadVideoCallback) {
        LogWarning("ReadVideoCallback is null.\n");
    }
    if (AVMEDIA_TYPE_AUDIO == mFFmpegMediaType && nullptr == mReadVideoCallback) {
        LogWarning("ReadVideoCallback is null.\n");
    }
    AVPacket packet;
    unsigned int playTimeMs = 0;
    // av_new_packet(&packet, AV_INPUT_BUFFER_MIN_SIZE);
    while (av_read_frame(pFormatCtx, &packet) >= 0) {
        if (nullptr == mReadVideoCallback) {
            av_packet_unref(&packet);
            continue;
        }
        if (false == mTaskRuning) {
            LogInfo("Stop read file thread.\n");
            break;
        }
        // Checks whether the packet belongs to a video stream.
        if (packet.stream_index == mediaStreamIndex) {
            playTimeMs = (packet.duration * pFormatCtx->streams[mediaStreamIndex]->time_base.num * 1000) /
                         pFormatCtx->streams[mediaStreamIndex]->time_base.den;
            // LogInfo("Frame data address: %p, length: %zu\n", packet.data, packet.size);
            // LogInfo("Play time ms:%d\n", playTimeMs);
            ReadFrame(&packet);
            std::this_thread::sleep_for(std::chrono::milliseconds(playTimeMs));
        }
        // Release the data packet.
        av_packet_unref(&packet);
    }
    av_packet_unref(&packet);

    avformat_close_input(&pFormatCtx);
}
void inline FfmpegReadFile::ReadFrame(AVPacket *packet)
{
    if (AVMEDIA_TYPE_VIDEO == mFFmpegMediaType) {
        mReadVideoCallback(packet->data, packet->size, mReadVideoCallbackContext);
    }
    else if (AVMEDIA_TYPE_AUDIO == mFFmpegMediaType) {
        mReadVideoCallback(packet->data, packet->size, mReadVideoCallbackContext);
    }
}