/*
This file is part of jpcsp.

Jpcsp is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Jpcsp is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Jpcsp.  If not, see <http://www.gnu.org/licenses/>.
 */
package jpcsp.media.codec.aac;

import static jpcsp.media.codec.aac.AacDecoder.AAC_ERROR;
import jpcsp.media.codec.util.IBitReader;

public class AACADTSHeaderInfo {
	int sampleRate;
	int samples;
	int bitRate;
	boolean crcAbsent;
	int objectType;
	int samplingIndex;
	int chanConfig;
	int numAacFrames;

	private static final int  AAC_ADTS_HEADER_SIZE = 7;

	private static final int mpeg4audioSampleRates[] = {
	    96000, 88200, 64000, 48000, 44100, 32000,
	    24000, 22050, 16000, 12000, 11025, 8000, 7350,
	    0, 0, 0
	};

	public int parse(IBitReader br) {
		if (br.read(12) != 0xFFF) {
			return AAC_ERROR;
		}

		br.skip(1);                     // id
		br.skip(2);                     // layer
		boolean crcAbs = br.readBool(); // protection_absent
		int aot = br.read(2);           // profile_objecttype
		int sr = br.read(4);            // sample_frequency_index
		if (mpeg4audioSampleRates[sr] == 0) {
			return AAC_ERROR;
		}
		br.skip(1);                     // private_bit
		int ch = br.read(3);            // channel_configuration

		br.skip(1);                     // original/copy
		br.skip(1);                     // home

		// adts_variable_header
		br.skip(1);                     // copyright_identification_bit
		br.skip(1);                     // copyright_identification_start
		int size = br.read(13);         // aac_frame_length
		if (size < AAC_ADTS_HEADER_SIZE) {
			return AAC_ERROR;
		}

		br.skip(11);                    // adts_buffer_fullness
		int rdb = br.read(2);           // number_of_raw_data_blocks_in_frame

		objectType    = aot + 1;
		chanConfig    = ch;
		crcAbsent     = crcAbs;
		numAacFrames  = rdb + 1;
		samplingIndex = sr;
		sampleRate    = mpeg4audioSampleRates[sr];
		samples       = (rdb + 1) * 1024;
		bitRate       = size * 8 * sampleRate / samples;

		return size;
	}
}