/**
 * Copyright (C) 2021 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 <IMediaExtractor.h>
#include <dlfcn.h>
#include <signal.h>
#include <stdlib.h>
#include <fcntl.h>

#include "../includes/common.h"
#include "../includes/memutils.h"

#if _32_BIT
#define LIBNAME "/system/lib/extractors/libmidiextractor.so"
#define LIBNAME_APEX                                                           \
  "/apex/com.android.media/lib/extractors/libmidiextractor.so"
#elif _64_BIT
#define LIBNAME "/system/lib64/extractors/libmidiextractor.so"
#define LIBNAME_APEX                                                           \
  "/apex/com.android.media/lib64/extractors/libmidiextractor.so"
#endif

char enable_selective_overload = ENABLE_NONE;

using namespace android;

class XMFDataSource : public DataSource {
public:
  int mFdData;
  int mFdInfo;
  XMFDataSource(int fdData, int fdInfo) {
    mFdData = fdData;
    mFdInfo = fdInfo;
  }

  ~XMFDataSource() = default;

  virtual ssize_t readAt(off64_t offset __attribute__((unused)), void *data,
                         size_t size) {
    uint32_t infoOffset, infoSize;
    read(mFdInfo, &infoSize, sizeof(int32_t));
    read(mFdInfo, &infoOffset, sizeof(int32_t));
    lseek(mFdData, infoOffset, SEEK_SET);
    read(mFdData, data, infoSize);
    return size;
  }

  virtual status_t getSize(off64_t *size) {
    *size = 0x10000;
    return 0;
  }
  virtual status_t initCheck() const { return 0; }
};

void close_resources(int fdData, int fdInfo, void *libHandle) {
  if (fdData >= 0) {
    ::close(fdData);
  }
  if (fdInfo >= 0) {
    ::close(fdInfo);
  }
  if (libHandle) {
    dlclose(libHandle);
  }
}

int main(int argc, char **argv) {
  if (argc < 3) {
    return EXIT_FAILURE;
  }
  enable_selective_overload = ENABLE_ALL;
  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;
  }

  int fdData = open(argv[1], O_RDONLY);
  if (fdData < 0) {
    dlclose(libHandle);
    return EXIT_FAILURE;
  }
  int fdInfo = open(argv[2], O_RDONLY);
  if (fdInfo < 0) {
    close_resources(fdData, fdInfo, libHandle);
    return EXIT_FAILURE;
  }

  sp<DataSource> dataSource = (sp<DataSource>)new XMFDataSource(fdData, fdInfo);
  if (!dataSource) {
    close_resources(fdData, fdInfo, libHandle);
    return EXIT_FAILURE;
  }

  void *meta = nullptr;
  FreeMetaFunc freeMeta = nullptr;

  float confidence = 0.0f;
  if (getDef().def_version == EXTRACTORDEF_VERSION_NDK_V1) {
    getDef().u.v2.sniff(dataSource->wrap(), &confidence, &meta, &freeMeta);
  } else if (getDef().def_version == EXTRACTORDEF_VERSION_NDK_V2) {
    getDef().u.v3.sniff(dataSource->wrap(), &confidence, &meta, &freeMeta);
  }

  close_resources(fdData, fdInfo, libHandle);
  enable_selective_overload = ENABLE_NONE;
  return EXIT_SUCCESS;
}