include/media/Metadata.h

/*
 * Copyright (C) 2009 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.
 */

#ifndef ANDROID_MEDIA_METADATA_H__
#define ANDROID_MEDIA_METADATA_H__

#include <sys/types.h>
#include <utils/Errors.h>
#include <utils/RefBase.h>
#include <utils/SortedVector.h>

namespace android {
class Parcel;

namespace media {

// Metadata is a class to build/serialize a set of metadata in a Parcel.
//
// This class should be kept in sync with android/media/Metadata.java.
// It provides all the metadata ids available and methods to build the
// header, add records and adjust the set size header field.
//
// Typical Usage:
// ==============
//  Parcel p;
//  media::Metadata data(&p);
//
//  data.appendHeader();
//  data.appendBool(Metadata::kPauseAvailable, true);
//   ... more append ...
//  data.updateLength();
//

class Metadata {
  public:
    typedef int32_t Type;
    typedef SortedVector<Type> Filter;

    static const Type kAny = 0;

    // Playback capabilities.
    static const Type kPauseAvailable        = 1; // Boolean
    static const Type kSeekBackwardAvailable = 2; // Boolean
    static const Type kSeekForwardAvailable  = 3; // Boolean
    static const Type kSeekAvailable         = 4; // Boolean

    // Keep in sync with android/media/Metadata.java
    static const Type kTitle                 = 5; // String
    static const Type kComment               = 6; // String
    static const Type kCopyright             = 7; // String
    static const Type kAlbum                 = 8; // String
    static const Type kArtist                = 9; // String
    static const Type kAuthor                = 10; // String
    static const Type kComposer              = 11; // String
    static const Type kGenre                 = 12; // String
    static const Type kDate                  = 13; // Date
    static const Type kDuration              = 14; // Integer(millisec)
    static const Type kCdTrackNum            = 15; // Integer 1-based
    static const Type kCdTrackMax            = 16; // Integer
    static const Type kRating                = 17; // String
    static const Type kAlbumArt              = 18; // byte[]
    static const Type kVideoFrame            = 19; // Bitmap

    static const Type kBitRate               = 20; // Integer, Aggregate rate of
    // all the streams in bps.

    static const Type kAudioBitRate          = 21; // Integer, bps
    static const Type kVideoBitRate          = 22; // Integer, bps
    static const Type kAudioSampleRate       = 23; // Integer, Hz
    static const Type kVideoframeRate        = 24; // Integer, Hz

    // See RFC2046 and RFC4281.
    static const Type kMimeType              = 25; // String
    static const Type kAudioCodec            = 26; // String
    static const Type kVideoCodec            = 27; // String

    static const Type kVideoHeight           = 28; // Integer
    static const Type kVideoWidth            = 29; // Integer
    static const Type kNumTracks             = 30; // Integer
    static const Type kDrmCrippled           = 31; // Boolean

    // @param p[inout] The parcel to append the metadata records
    // to. The global metadata header should have been set already.
    explicit Metadata(Parcel *p);
    ~Metadata();

    // Rewind the underlying parcel, undoing all the changes.
    void resetParcel();

    // Append the size and 'META' marker.
    bool appendHeader();

    // Once all the records have been added, call this to update the
    // lenght field in the header.
    void updateLength();

    // append* are methods to append metadata.
    // @param key Is the metadata Id.
    // @param val Is the value of the metadata.
    // @return true if successful, false otherwise.
    // TODO: add more as needed to handle other types.
    bool appendBool(Type key, bool val);
    bool appendInt32(Type key, int32_t val);

  private:
    Metadata(const Metadata&);
    Metadata& operator=(const Metadata&);


    // Checks the key is valid and not already present.
    bool checkKey(Type key);

    Parcel *mData;
    size_t mBegin;
};

}  // namespace android::media
}  // namespace android

#endif  // ANDROID_MEDIA_METADATA_H__