<?php

/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at https://github.com/JamesHeinrich/getID3       //
//            or https://www.getid3.org                        //
//            or http://getid3.sourceforge.net                 //
//  see readme.txt for more details                            //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.audio.wavpack.php                                    //
// module for analyzing WavPack v4.0+ Audio files              //
// dependencies: NONE                                          //
//                                                            ///
/////////////////////////////////////////////////////////////////

if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
	exit;
}
class getid3_wavpack extends getid3_handler
{
	/**
	 * @return bool
	 */
	public function Analyze() {
		$info = &$this->getid3->info;

		$this->fseek($info['avdataoffset']);

		while (true) {

			$wavpackheader = $this->fread(32);

			if ($this->ftell() >= $info['avdataend']) {
				break;
			} elseif (feof($this->getid3->fp)) {
				break;
			} elseif (
				isset($info['wavpack']['blockheader']['total_samples']) &&
				isset($info['wavpack']['blockheader']['block_samples']) &&
				($info['wavpack']['blockheader']['total_samples'] > 0) &&
				($info['wavpack']['blockheader']['block_samples'] > 0) &&
				(!isset($info['wavpack']['riff_trailer_size']) || ($info['wavpack']['riff_trailer_size'] <= 0)) &&
				((isset($info['wavpack']['config_flags']['md5_checksum']) && ($info['wavpack']['config_flags']['md5_checksum'] === false)) || !empty($info['md5_data_source']))) {
					break;
			}

			$blockheader_offset = $this->ftell() - 32;
			$blockheader_magic  =                              substr($wavpackheader,  0,  4);
			$blockheader_size   = getid3_lib::LittleEndian2Int(substr($wavpackheader,  4,  4));

			$magic = 'wvpk';
			if ($blockheader_magic != $magic) {
				$this->error('Expecting "'.getid3_lib::PrintHexBytes($magic).'" at offset '.$blockheader_offset.', found "'.getid3_lib::PrintHexBytes($blockheader_magic).'"');
				switch (isset($info['audio']['dataformat']) ? $info['audio']['dataformat'] : '') {
					case 'wavpack':
					case 'wvc':
						break;
					default:
						unset($info['fileformat']);
						unset($info['audio']);
						unset($info['wavpack']);
						break;
				}
				return false;
			}

			if (empty($info['wavpack']['blockheader']['block_samples']) ||
				empty($info['wavpack']['blockheader']['total_samples']) ||
				($info['wavpack']['blockheader']['block_samples'] <= 0) ||
				($info['wavpack']['blockheader']['total_samples'] <= 0)) {
				// Also, it is possible that the first block might not have
				// any samples (block_samples == 0) and in this case you should skip blocks
				// until you find one with samples because the other information (like
				// total_samples) are not guaranteed to be correct until (block_samples > 0)

				// Finally, I have defined a format for files in which the length is not known
				// (for example when raw files are created using pipes). In these cases
				// total_samples will be -1 and you must seek to the final block to determine
				// the total number of samples.


				$info['audio']['dataformat']   = 'wavpack';
				$info['fileformat']            = 'wavpack';
				$info['audio']['lossless']     = true;
				$info['audio']['bitrate_mode'] = 'vbr';

				$info['wavpack']['blockheader']['offset'] = $blockheader_offset;
				$info['wavpack']['blockheader']['magic']  = $blockheader_magic;
				$info['wavpack']['blockheader']['size']   = $blockheader_size;

				if ($info['wavpack']['blockheader']['size'] >= 0x100000) {
					$this->error('Expecting WavPack block size less than "0x100000", found "'.$info['wavpack']['blockheader']['size'].'" at offset '.$info['wavpack']['blockheader']['offset']);
					switch (isset($info['audio']['dataformat']) ? $info['audio']['dataformat'] : '') {
						case 'wavpack':
						case 'wvc':
							break;
						default:
							unset($info['fileformat']);
							unset($info['audio']);
							unset($info['wavpack']);
							break;
					}
					return false;
				}

				$info['wavpack']['blockheader']['minor_version'] = ord($wavpackheader[8]);
				$info['wavpack']['blockheader']['major_version'] = ord($wavpackheader[9]);

				if (($info['wavpack']['blockheader']['major_version'] != 4) ||
					(($info['wavpack']['blockheader']['minor_version'] < 4) &&
					($info['wavpack']['blockheader']['minor_version'] > 16))) {
						$this->error('Expecting WavPack version between "4.2" and "4.16", found version "'.$info['wavpack']['blockheader']['major_version'].'.'.$info['wavpack']['blockheader']['minor_version'].'" at offset '.$info['wavpack']['blockheader']['offset']);
						switch (isset($info['audio']['dataformat']) ? $info['audio']['dataformat'] : '') {
							case 'wavpack':
							case 'wvc':
								break;
							default:
								unset($info['fileformat']);
								unset($info['audio']);
								unset($info['wavpack']);
								break;
						}
						return false;
				}

				$info['wavpack']['blockheader']['track_number']  = ord($wavpackheader[10]); // unused
				$info['wavpack']['blockheader']['index_number']  = ord($wavpackheader[11]); // unused
				$info['wavpack']['blockheader']['total_samples'] = getid3_lib::LittleEndian2Int(substr($wavpackheader, 12,  4));
				$info['wavpack']['blockheader']['block_index']   = getid3_lib::LittleEndian2Int(substr($wavpackheader, 16,  4));
				$info['wavpack']['blockheader']['block_samples'] = getid3_lib::LittleEndian2Int(substr($wavpackheader, 20,  4));
				$info['wavpack']['blockheader']['flags_raw']     = getid3_lib::LittleEndian2Int(substr($wavpackheader, 24,  4));
				$info['wavpack']['blockheader']['crc']           = getid3_lib::LittleEndian2Int(substr($wavpackheader, 28,  4));

				$info['wavpack']['blockheader']['flags']['bytes_per_sample']     =    1 + ($info['wavpack']['blockheader']['flags_raw'] & 0x00000003);
				$info['wavpack']['blockheader']['flags']['mono']                 = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000004);
				$info['wavpack']['blockheader']['flags']['hybrid']               = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000008);
				$info['wavpack']['blockheader']['flags']['joint_stereo']         = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000010);
				$info['wavpack']['blockheader']['flags']['cross_decorrelation']  = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000020);
				$info['wavpack']['blockheader']['flags']['hybrid_noiseshape']    = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000040);
				$info['wavpack']['blockheader']['flags']['ieee_32bit_float']     = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000080);
				$info['wavpack']['blockheader']['flags']['int_32bit']            = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000100);
				$info['wavpack']['blockheader']['flags']['hybrid_bitrate_noise'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000200);
				$info['wavpack']['blockheader']['flags']['hybrid_balance_noise'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000400);
				$info['wavpack']['blockheader']['flags']['multichannel_initial'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000800);
				$info['wavpack']['blockheader']['flags']['multichannel_final']   = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00001000);

				$info['audio']['lossless'] = !$info['wavpack']['blockheader']['flags']['hybrid'];
			}

			while (!feof($this->getid3->fp) && ($this->ftell() < ($blockheader_offset + $blockheader_size + 8))) {

				$metablock = array('offset'=>$this->ftell());
				$metablockheader = $this->fread(2);
				if (feof($this->getid3->fp)) {
					break;
				}
				$metablock['id'] = ord($metablockheader[0]);
				$metablock['function_id'] = ($metablock['id'] & 0x3F);
				$metablock['function_name'] = $this->WavPackMetablockNameLookup($metablock['function_id']);

				// The 0x20 bit in the id of the meta subblocks (which is defined as
				// ID_OPTIONAL_DATA) is a permanent part of the id. The idea is that
				// if a decoder encounters an id that it does not know about, it uses
				// that "ID_OPTIONAL_DATA" flag to determine what to do. If it is set
				// then the decoder simply ignores the metadata, but if it is zero
				// then the decoder should quit because it means that an understanding
				// of the metadata is required to correctly decode the audio.
				$metablock['non_decoder'] = (bool) ($metablock['id'] & 0x20);

				$metablock['padded_data'] = (bool) ($metablock['id'] & 0x40);
				$metablock['large_block'] = (bool) ($metablock['id'] & 0x80);
				if ($metablock['large_block']) {
					$metablockheader .= $this->fread(2);
				}
				$metablock['size'] = getid3_lib::LittleEndian2Int(substr($metablockheader, 1)) * 2; // size is stored in words
				$metablock['data'] = null;
				$metablock['comments'] = array();

				if ($metablock['size'] > 0) {

					switch ($metablock['function_id']) {
						case 0x21: // ID_RIFF_HEADER
						case 0x22: // ID_RIFF_TRAILER
						case 0x23: // ID_REPLAY_GAIN
						case 0x24: // ID_CUESHEET
						case 0x25: // ID_CONFIG_BLOCK
						case 0x26: // ID_MD5_CHECKSUM
							$metablock['data'] = $this->fread($metablock['size']);

							if ($metablock['padded_data']) {
								// padded to the nearest even byte
								$metablock['size']--;
								$metablock['data'] = substr($metablock['data'], 0, -1);
							}
							break;

						case 0x00: // ID_DUMMY
						case 0x01: // ID_ENCODER_INFO
						case 0x02: // ID_DECORR_TERMS
						case 0x03: // ID_DECORR_WEIGHTS
						case 0x04: // ID_DECORR_SAMPLES
						case 0x05: // ID_ENTROPY_VARS
						case 0x06: // ID_HYBRID_PROFILE
						case 0x07: // ID_SHAPING_WEIGHTS
						case 0x08: // ID_FLOAT_INFO
						case 0x09: // ID_INT32_INFO
						case 0x0A: // ID_WV_BITSTREAM
						case 0x0B: // ID_WVC_BITSTREAM
						case 0x0C: // ID_WVX_BITSTREAM
						case 0x0D: // ID_CHANNEL_INFO
							$this->fseek($metablock['offset'] + ($metablock['large_block'] ? 4 : 2) + $metablock['size']);
							break;

						default:
							$this->warning('Unexpected metablock type "0x'.str_pad(dechex($metablock['function_id']), 2, '0', STR_PAD_LEFT).'" at offset '.$metablock['offset']);
							$this->fseek($metablock['offset'] + ($metablock['large_block'] ? 4 : 2) + $metablock['size']);
							break;
					}

					switch ($metablock['function_id']) {
						case 0x21: // ID_RIFF_HEADER
							getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true);
							$original_wav_filesize = getid3_lib::LittleEndian2Int(substr($metablock['data'], 4, 4));

							$getid3_temp = new getID3();
							$getid3_temp->openfile($this->getid3->filename);
							$getid3_riff = new getid3_riff($getid3_temp);
							$getid3_riff->ParseRIFFdata($metablock['data']);
							$metablock['riff']            = $getid3_temp->info['riff'];
							$info['audio']['sample_rate'] = $getid3_temp->info['riff']['raw']['fmt ']['nSamplesPerSec'];
							unset($getid3_riff, $getid3_temp);

							$metablock['riff']['original_filesize'] = $original_wav_filesize;
							$info['wavpack']['riff_trailer_size'] = $original_wav_filesize - $metablock['riff']['WAVE']['data'][0]['size'] - $metablock['riff']['header_size'];
							$info['playtime_seconds'] = $info['wavpack']['blockheader']['total_samples'] / $info['audio']['sample_rate'];

							// Safe RIFF header in case there's a RIFF footer later
							$metablockRIFFheader = $metablock['data'];
							break;


						case 0x22: // ID_RIFF_TRAILER
							$metablockRIFFfooter = isset($metablockRIFFheader) ? $metablockRIFFheader : ''.$metablock['data'];
							getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true);

							$startoffset = $metablock['offset'] + ($metablock['large_block'] ? 4 : 2);
							$getid3_temp = new getID3();
							$getid3_temp->openfile($this->getid3->filename);
							$getid3_temp->info['avdataend']  = $info['avdataend'];
							//$getid3_temp->info['fileformat'] = 'riff';
							$getid3_riff = new getid3_riff($getid3_temp);
							$metablock['riff'] = $getid3_riff->ParseRIFF($startoffset, $startoffset + $metablock['size']);

							if (!empty($metablock['riff']['INFO'])) {
								getid3_riff::parseComments($metablock['riff']['INFO'], $metablock['comments']);
								$info['tags']['riff'] = $metablock['comments'];
							}
							unset($getid3_temp, $getid3_riff);
							break;


						case 0x23: // ID_REPLAY_GAIN
							$this->warning('WavPack "Replay Gain" contents not yet handled by getID3() in metablock at offset '.$metablock['offset']);
							break;


						case 0x24: // ID_CUESHEET
							$this->warning('WavPack "Cuesheet" contents not yet handled by getID3() in metablock at offset '.$metablock['offset']);
							break;


						case 0x25: // ID_CONFIG_BLOCK
							$metablock['flags_raw'] = getid3_lib::LittleEndian2Int(substr($metablock['data'], 0, 3));

							$metablock['flags']['adobe_mode']     = (bool) ($metablock['flags_raw'] & 0x000001); // "adobe" mode for 32-bit floats
							$metablock['flags']['fast_flag']      = (bool) ($metablock['flags_raw'] & 0x000002); // fast mode
							$metablock['flags']['very_fast_flag'] = (bool) ($metablock['flags_raw'] & 0x000004); // double fast
							$metablock['flags']['high_flag']      = (bool) ($metablock['flags_raw'] & 0x000008); // high quality mode
							$metablock['flags']['very_high_flag'] = (bool) ($metablock['flags_raw'] & 0x000010); // double high (not used yet)
							$metablock['flags']['bitrate_kbps']   = (bool) ($metablock['flags_raw'] & 0x000020); // bitrate is kbps, not bits / sample
							$metablock['flags']['auto_shaping']   = (bool) ($metablock['flags_raw'] & 0x000040); // automatic noise shaping
							$metablock['flags']['shape_override'] = (bool) ($metablock['flags_raw'] & 0x000080); // shaping mode specified
							$metablock['flags']['joint_override'] = (bool) ($metablock['flags_raw'] & 0x000100); // joint-stereo mode specified
							$metablock['flags']['copy_time']      = (bool) ($metablock['flags_raw'] & 0x000200); // copy file-time from source
							$metablock['flags']['create_exe']     = (bool) ($metablock['flags_raw'] & 0x000400); // create executable
							$metablock['flags']['create_wvc']     = (bool) ($metablock['flags_raw'] & 0x000800); // create correction file
							$metablock['flags']['optimize_wvc']   = (bool) ($metablock['flags_raw'] & 0x001000); // maximize bybrid compression
							$metablock['flags']['quality_mode']   = (bool) ($metablock['flags_raw'] & 0x002000); // psychoacoustic quality mode
							$metablock['flags']['raw_flag']       = (bool) ($metablock['flags_raw'] & 0x004000); // raw mode (not implemented yet)
							$metablock['flags']['calc_noise']     = (bool) ($metablock['flags_raw'] & 0x008000); // calc noise in hybrid mode
							$metablock['flags']['lossy_mode']     = (bool) ($metablock['flags_raw'] & 0x010000); // obsolete (for information)
							$metablock['flags']['extra_mode']     = (bool) ($metablock['flags_raw'] & 0x020000); // extra processing mode
							$metablock['flags']['skip_wvx']       = (bool) ($metablock['flags_raw'] & 0x040000); // no wvx stream w/ floats & big ints
							$metablock['flags']['md5_checksum']   = (bool) ($metablock['flags_raw'] & 0x080000); // compute & store MD5 signature
							$metablock['flags']['quiet_mode']     = (bool) ($metablock['flags_raw'] & 0x100000); // don't report progress %

							$info['wavpack']['config_flags'] = $metablock['flags'];


							$info['audio']['encoder_options'] = '';
							if ($info['wavpack']['blockheader']['flags']['hybrid']) {
								$info['audio']['encoder_options'] .= ' -b???';
							}
							$info['audio']['encoder_options'] .= ($metablock['flags']['adobe_mode']     ? ' -a' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['optimize_wvc']   ? ' -cc' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['create_exe']     ? ' -e' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['fast_flag']      ? ' -f' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['joint_override'] ? ' -j?' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['high_flag']      ? ' -h' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['md5_checksum']   ? ' -m' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['calc_noise']     ? ' -n' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['shape_override'] ? ' -s?' : '');
							$info['audio']['encoder_options'] .= ($metablock['flags']['extra_mode']     ? ' -x?' : '');
							if (!empty($info['audio']['encoder_options'])) {
								$info['audio']['encoder_options'] = trim($info['audio']['encoder_options']);
							} elseif (isset($info['audio']['encoder_options'])) {
								unset($info['audio']['encoder_options']);
							}
							break;


						case 0x26: // ID_MD5_CHECKSUM
							if (strlen($metablock['data']) == 16) {
								$info['md5_data_source'] = strtolower(getid3_lib::PrintHexBytes($metablock['data'], true, false, false));
							} else {
								$this->warning('Expecting 16 bytes of WavPack "MD5 Checksum" in metablock at offset '.$metablock['offset'].', but found '.strlen($metablock['data']).' bytes');
							}
							break;


						case 0x00: // ID_DUMMY
						case 0x01: // ID_ENCODER_INFO
						case 0x02: // ID_DECORR_TERMS
						case 0x03: // ID_DECORR_WEIGHTS
						case 0x04: // ID_DECORR_SAMPLES
						case 0x05: // ID_ENTROPY_VARS
						case 0x06: // ID_HYBRID_PROFILE
						case 0x07: // ID_SHAPING_WEIGHTS
						case 0x08: // ID_FLOAT_INFO
						case 0x09: // ID_INT32_INFO
						case 0x0A: // ID_WV_BITSTREAM
						case 0x0B: // ID_WVC_BITSTREAM
						case 0x0C: // ID_WVX_BITSTREAM
						case 0x0D: // ID_CHANNEL_INFO
							unset($metablock);
							break;
					}

				}
				if (!empty($metablock)) {
					$info['wavpack']['metablocks'][] = $metablock;
				}

			}

		}

		$info['audio']['encoder']         = 'WavPack v'.$info['wavpack']['blockheader']['major_version'].'.'.str_pad($info['wavpack']['blockheader']['minor_version'], 2, '0', STR_PAD_LEFT);
		$info['audio']['bits_per_sample'] = $info['wavpack']['blockheader']['flags']['bytes_per_sample'] * 8;
		$info['audio']['channels']        = ($info['wavpack']['blockheader']['flags']['mono'] ? 1 : 2);

		if (!empty($info['playtime_seconds'])) {

			$info['audio']['bitrate']     = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds'];

		} else {

			$info['audio']['dataformat']  = 'wvc';

		}

		return true;
	}

	/**
	 * @param int $id
	 *
	 * @return string
	 */
	public function WavPackMetablockNameLookup(&$id) {
		static $WavPackMetablockNameLookup = array(
			0x00 => 'Dummy',
			0x01 => 'Encoder Info',
			0x02 => 'Decorrelation Terms',
			0x03 => 'Decorrelation Weights',
			0x04 => 'Decorrelation Samples',
			0x05 => 'Entropy Variables',
			0x06 => 'Hybrid Profile',
			0x07 => 'Shaping Weights',
			0x08 => 'Float Info',
			0x09 => 'Int32 Info',
			0x0A => 'WV Bitstream',
			0x0B => 'WVC Bitstream',
			0x0C => 'WVX Bitstream',
			0x0D => 'Channel Info',
			0x21 => 'RIFF header',
			0x22 => 'RIFF trailer',
			0x23 => 'Replay Gain',
			0x24 => 'Cuesheet',
			0x25 => 'Config Block',
			0x26 => 'MD5 Checksum',
		);
		return (isset($WavPackMetablockNameLookup[$id]) ? $WavPackMetablockNameLookup[$id] : '');
	}

}
