/*
 * Copyright (C) 2012 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.
 */

package android.media;

import android.annotation.NonNull;
import android.media.MediaCryptoException;
import java.util.UUID;

MediaCrypto class can be used in conjunction with MediaCodec to decode encrypted media data. Crypto schemes are assigned 16 byte UUIDs, the method isCryptoSchemeSupported can be used to query if a given scheme is supported on the device. /**
 * MediaCrypto class can be used in conjunction with {@link android.media.MediaCodec}
 * to decode encrypted media data.
 *
 * Crypto schemes are assigned 16 byte UUIDs,
 * the method {@link #isCryptoSchemeSupported} can be used to query if a given
 * scheme is supported on the device.
 *
 */
public final class MediaCrypto {
    
Query if the given scheme identified by its UUID is supported on
this device.
Params:
uuid – The UUID of the crypto scheme./**
     * Query if the given scheme identified by its UUID is supported on
     * this device.
     * @param uuid The UUID of the crypto scheme.
     */
    public static final boolean isCryptoSchemeSupported(@NonNull UUID uuid) {
        return isCryptoSchemeSupportedNative(getByteArrayFromUUID(uuid));
    }

    @NonNull
    private static final byte[] getByteArrayFromUUID(@NonNull UUID uuid) {
        long msb = uuid.getMostSignificantBits();
        long lsb = uuid.getLeastSignificantBits();

        byte[] uuidBytes = new byte[16];
        for (int i = 0; i < 8; ++i) {
            uuidBytes[i] = (byte)(msb >>> (8 * (7 - i)));
            uuidBytes[8 + i] = (byte)(lsb >>> (8 * (7 - i)));
        }

        return uuidBytes;
    }

    private static final native boolean isCryptoSchemeSupportedNative(@NonNull byte[] uuid);

    
Instantiate a MediaCrypto object using opaque, crypto scheme specific
data.
Params:
uuid – The UUID of the crypto scheme.
initData – Opaque initialization data specific to the crypto scheme./**
     * Instantiate a MediaCrypto object using opaque, crypto scheme specific
     * data.
     * @param uuid The UUID of the crypto scheme.
     * @param initData Opaque initialization data specific to the crypto scheme.
     */
    public MediaCrypto(@NonNull UUID uuid, @NonNull byte[] initData) throws MediaCryptoException {
        native_setup(getByteArrayFromUUID(uuid), initData);
    }

    
Query if the crypto scheme requires the use of a secure decoder
to decode data of the given mime type.
Params:
mime – The mime type of the media data/**
     * Query if the crypto scheme requires the use of a secure decoder
     * to decode data of the given mime type.
     * @param mime The mime type of the media data
     */
    public final native boolean requiresSecureDecoderComponent(@NonNull String mime);

    
Associate a MediaDrm session with this MediaCrypto instance. The MediaDrm session is used to securely load decryption keys for a crypto scheme. The crypto keys loaded through the MediaDrm session may be selected for use during the decryption operation performed by MediaCodec.queueSecureInputBuffer by specifying their key ids in the CryptoInfo.key field. 
Params:
sessionId – the MediaDrm sessionId to associate with this
MediaCrypto instance
Throws:
MediaCryptoException – on failure to set the sessionId/**
     * Associate a MediaDrm session with this MediaCrypto instance.  The
     * MediaDrm session is used to securely load decryption keys for a
     * crypto scheme.  The crypto keys loaded through the MediaDrm session
     * may be selected for use during the decryption operation performed
     * by {@link android.media.MediaCodec#queueSecureInputBuffer} by specifying
     * their key ids in the {@link android.media.MediaCodec.CryptoInfo#key} field.
     * @param sessionId the MediaDrm sessionId to associate with this
     * MediaCrypto instance
     * @throws MediaCryptoException on failure to set the sessionId
     */
    public final native void setMediaDrmSession(@NonNull byte[] sessionId)
        throws MediaCryptoException;

    @Override
    protected void finalize() {
        native_finalize();
    }

    public native final void release();
    private static native final void native_init();

    private native final void native_setup(@NonNull byte[] uuid, @NonNull byte[] initData)
        throws MediaCryptoException;

    private native final void native_finalize();

    static {
        System.loadLibrary("media_jni");
        native_init();
    }

    private long mNativeContext;
}