/* Change playlist. The response comes as plain XML. */
public void sendChangePlaylist(
ChannelListener listener, Playlist playlist, String xml, String packetDescription)
throws DespotifyException {
/* Create channel and buffer. */
Channel channel = new Channel("Change-Playlist-Channel", Channel.Type.TYPE_PLAYLIST, listener);
byte[] xmlBytes = xml.getBytes();
ByteBuffer buffer = ByteBuffer.allocate(2 + 17 + 4 + 4 + 4 + 1 + 1 + xmlBytes.length);
/* Append channel id, playlist id and some bytes... */
buffer.putShort((short) channel.getId());
buffer.put(playlist.getByteUUID()); /* 16 bytes */
buffer.put((byte) 0x00); // 0x00 for adding tracks, 0x02 for the rest?
buffer.putInt(playlist.getRevision().intValue());
buffer.putInt(playlist.getTracks().size());
buffer.putInt(playlist.getChecksum().intValue()); /* -1: Create playlist. */
buffer.put((byte) (playlist.isCollaborative() ? 0x01 : 0x00));
buffer.put((byte) 0x03); /* Unknown */
buffer.put(xmlBytes);
buffer.flip();
/* Register channel. */
Channel.register(channel);
/* Send packet. */
this.sendPacket(PacketType.changePlaylist, buffer, packetDescription);
}
/* Request image using a 20 byte id. The response is a JPG. */
public void sendImageRequest(ChannelListener listener, String id) throws DespotifyException {
/* Create channel and buffer. */
Channel channel = new Channel("Image-Channel", Channel.Type.TYPE_IMAGE, listener);
ByteBuffer buffer = ByteBuffer.allocate(2 + 20);
/* Append channel id and image hash. */
buffer.putShort((short) channel.getId());
buffer.put(Hex.toBytes(id));
buffer.flip();
/* Register channel. */
Channel.register(channel);
/* Send packet. */
this.sendPacket(PacketType.image, buffer);
}
/* Request ads. The response is GZIP compressed XML. */
public void sendAdRequest(ChannelListener listener, int type) throws DespotifyException {
/* Create channel and buffer. */
Channel channel = new Channel("Ad-Channel", Channel.Type.TYPE_AD, listener);
ByteBuffer buffer = ByteBuffer.allocate(2 + 1);
/* Append channel id and ad type. */
buffer.putShort((short) channel.getId());
buffer.put((byte) type);
buffer.flip();
/* Register channel. */
Channel.register(channel);
/* Send packet. */
this.sendPacket(PacketType.requestAd, buffer);
}
/* Request AES key for a track. */
public void sendAesKeyRequest(ChannelListener listener, Track track) throws DespotifyException {
/* Create channel and buffer. */
Channel channel = new Channel("AES-Key-Channel", Channel.Type.TYPE_AESKEY, listener);
ByteBuffer buffer = ByteBuffer.allocate(20 + 16 + 2 + 2);
/* Request the AES key for this file by sending the file id and track id. */
buffer.put(Hex.toBytes(track.getFiles().get(0))); /* 20 bytes */
buffer.put(track.getByteUUID()); /* 16 bytes */
buffer.putShort((short) 0x0000);
buffer.putShort((short) channel.getId());
buffer.flip();
/* Register channel. */
Channel.register(channel);
/* Send packet. */
this.sendPacket(PacketType.requestKey, buffer);
}
/*
* Request a part of the encrypted file from the server.
*
* The data should be decrypted using AES key in CTR mode
* with AES key provided and a static IV, incremented for
* each 16 byte data processed.
*/
public void sendSubstreamRequest(ChannelListener listener, Track track, int offset, int length)
throws DespotifyException {
/* Create channel and buffer. */
Channel channel = new Channel("Substream-Channel", Channel.Type.TYPE_SUBSTREAM, listener);
ByteBuffer buffer = ByteBuffer.allocate(2 + 2 + 2 + 2 + 2 + 2 + 4 + 20 + 4 + 4);
/* Append channel id. */
buffer.putShort((short) channel.getId());
/* Unknown 10 bytes. */
buffer.putShort((short) 0x0800);
buffer.putShort((short) 0x0000);
buffer.putShort((short) 0x0000);
buffer.putShort((short) 0x0000);
buffer.putShort((short) 0x4e20);
/* Unknown (static value) */
buffer.putInt(200 * 1000);
/* 20 bytes file id. */
buffer.put(Hex.toBytes(track.getFiles().get(0)));
if (offset % 4096 != 0 || length % 4096 != 0) {
throw new IllegalArgumentException("Offset and length need to be a multiple of 4096.");
}
offset >>= 2;
length >>= 2;
/* Append offset and length. */
buffer.putInt(offset);
buffer.putInt(offset + length);
buffer.flip();
/* Register channel. */
Channel.register(channel);
/* Send packet. */
this.sendPacket(PacketType.getSubStream, buffer);
}