<?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.tag.apetag.php                                       //

// module for analyzing APE tags                               //

// dependencies: NONE                                          //

//                                                            ///

/////////////////////////////////////////////////////////////////

if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers

	exit;

}

class getid3_apetag extends getid3_handler

{

	/**

	 * true: return full data for all attachments;

	 * false: return no data for all attachments;

	 * integer: return data for attachments <= than this;

	 * string: save as file to this directory.

	 *

	 * @var int|bool|string

	 */

	public $inline_attachments = true;

	public $overrideendoffset  = 0;

	/**

	 * @return bool

	 */

	public function Analyze() {

		$info = &$this->getid3->info;

		if (!getid3_lib::intValueSupported($info['filesize'])) {

			$this->warning('Unable to check for APEtags because file is larger than '.round(PHP_INT_MAX / 1073741824).'GB');

			return false;

		}

		$id3v1tagsize     = 128;

		$apetagheadersize = 32;

		$lyrics3tagsize   = 10;

		if ($this->overrideendoffset == 0) {

			$this->fseek(0 - $id3v1tagsize - $apetagheadersize - $lyrics3tagsize, SEEK_END);

			$APEfooterID3v1 = $this->fread($id3v1tagsize + $apetagheadersize + $lyrics3tagsize);

			//if (preg_match('/APETAGEX.{24}TAG.{125}$/i', $APEfooterID3v1)) {

			if (substr($APEfooterID3v1, strlen($APEfooterID3v1) - $id3v1tagsize - $apetagheadersize, 8) == 'APETAGEX') {

				// APE tag found before ID3v1

				$info['ape']['tag_offset_end'] = $info['filesize'] - $id3v1tagsize;

			//} elseif (preg_match('/APETAGEX.{24}$/i', $APEfooterID3v1)) {

			} elseif (substr($APEfooterID3v1, strlen($APEfooterID3v1) - $apetagheadersize, 8) == 'APETAGEX') {

				// APE tag found, no ID3v1

				$info['ape']['tag_offset_end'] = $info['filesize'];

			}

		} else {

			$this->fseek($this->overrideendoffset - $apetagheadersize);

			if ($this->fread(8) == 'APETAGEX') {

				$info['ape']['tag_offset_end'] = $this->overrideendoffset;

			}

		}

		if (!isset($info['ape']['tag_offset_end'])) {

			// APE tag not found

			unset($info['ape']);

			return false;

		}

		// shortcut

		$thisfile_ape = &$info['ape'];

		$this->fseek($thisfile_ape['tag_offset_end'] - $apetagheadersize);

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

		if (!($thisfile_ape['footer'] = $this->parseAPEheaderFooter($APEfooterData))) {

			$this->error('Error parsing APE footer at offset '.$thisfile_ape['tag_offset_end']);

			return false;

		}

		if (isset($thisfile_ape['footer']['flags']['header']) && $thisfile_ape['footer']['flags']['header']) {

			$this->fseek($thisfile_ape['tag_offset_end'] - $thisfile_ape['footer']['raw']['tagsize'] - $apetagheadersize);

			$thisfile_ape['tag_offset_start'] = $this->ftell();

			$APEtagData = $this->fread($thisfile_ape['footer']['raw']['tagsize'] + $apetagheadersize);

		} else {

			$thisfile_ape['tag_offset_start'] = $thisfile_ape['tag_offset_end'] - $thisfile_ape['footer']['raw']['tagsize'];

			$this->fseek($thisfile_ape['tag_offset_start']);

			$APEtagData = $this->fread($thisfile_ape['footer']['raw']['tagsize']);

		}

		$info['avdataend'] = $thisfile_ape['tag_offset_start'];

		if (isset($info['id3v1']['tag_offset_start']) && ($info['id3v1']['tag_offset_start'] < $thisfile_ape['tag_offset_end'])) {

			$this->warning('ID3v1 tag information ignored since it appears to be a false synch in APEtag data');

			unset($info['id3v1']);

			foreach ($info['warning'] as $key => $value) {

				if ($value == 'Some ID3v1 fields do not use NULL characters for padding') {

					unset($info['warning'][$key]);

					sort($info['warning']);

					break;

				}

			}

		}

		$offset = 0;

		if (isset($thisfile_ape['footer']['flags']['header']) && $thisfile_ape['footer']['flags']['header']) {

			if ($thisfile_ape['header'] = $this->parseAPEheaderFooter(substr($APEtagData, 0, $apetagheadersize))) {

				$offset += $apetagheadersize;

			} else {

				$this->error('Error parsing APE header at offset '.$thisfile_ape['tag_offset_start']);

				return false;

			}

		}

		// shortcut

		$info['replay_gain'] = array();

		$thisfile_replaygain = &$info['replay_gain'];

		for ($i = 0; $i < $thisfile_ape['footer']['raw']['tag_items']; $i++) {

			$value_size = getid3_lib::LittleEndian2Int(substr($APEtagData, $offset, 4));

			$offset += 4;

			$item_flags = getid3_lib::LittleEndian2Int(substr($APEtagData, $offset, 4));

			$offset += 4;

			if (strstr(substr($APEtagData, $offset), "\x00") === false) {

				$this->error('Cannot find null-byte (0x00) separator between ItemKey #'.$i.' and value. ItemKey starts '.$offset.' bytes into the APE tag, at file offset '.($thisfile_ape['tag_offset_start'] + $offset));

				return false;

			}

			$ItemKeyLength = strpos($APEtagData, "\x00", $offset) - $offset;

			$item_key      = strtolower(substr($APEtagData, $offset, $ItemKeyLength));

			// shortcut

			$thisfile_ape['items'][$item_key] = array();

			$thisfile_ape_items_current = &$thisfile_ape['items'][$item_key];

			$thisfile_ape_items_current['offset'] = $thisfile_ape['tag_offset_start'] + $offset;

			$offset += ($ItemKeyLength + 1); // skip 0x00 terminator

			$thisfile_ape_items_current['data'] = substr($APEtagData, $offset, $value_size);

			$offset += $value_size;

			$thisfile_ape_items_current['flags'] = $this->parseAPEtagFlags($item_flags);

			switch ($thisfile_ape_items_current['flags']['item_contents_raw']) {

				case 0: // UTF-8

				case 2: // Locator (URL, filename, etc), UTF-8 encoded

					$thisfile_ape_items_current['data'] = explode("\x00", $thisfile_ape_items_current['data']);

					break;

				case 1:  // binary data

				default:

					break;

			}

			switch (strtolower($item_key)) {

				// http://wiki.hydrogenaud.io/index.php?title=ReplayGain#MP3Gain

				case 'replaygain_track_gain':

					if (preg_match('#^([\\-\\+][0-9\\.,]{8})( dB)?$#', $thisfile_ape_items_current['data'][0], $matches)) {

						$thisfile_replaygain['track']['adjustment'] = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!

						$thisfile_replaygain['track']['originator'] = 'unspecified';

					} else {

						$this->warning('MP3gainTrackGain value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'replaygain_track_peak':

					if (preg_match('#^([0-9\\.,]{8})$#', $thisfile_ape_items_current['data'][0], $matches)) {

						$thisfile_replaygain['track']['peak']       = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!

						$thisfile_replaygain['track']['originator'] = 'unspecified';

						if ($thisfile_replaygain['track']['peak'] <= 0) {

							$this->warning('ReplayGain Track peak from APEtag appears invalid: '.$thisfile_replaygain['track']['peak'].' (original value = "'.$thisfile_ape_items_current['data'][0].'")');

						}

					} else {

						$this->warning('MP3gainTrackPeak value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'replaygain_album_gain':

					if (preg_match('#^([\\-\\+][0-9\\.,]{8})( dB)?$#', $thisfile_ape_items_current['data'][0], $matches)) {

						$thisfile_replaygain['album']['adjustment'] = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!

						$thisfile_replaygain['album']['originator'] = 'unspecified';

					} else {

						$this->warning('MP3gainAlbumGain value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'replaygain_album_peak':

					if (preg_match('#^([0-9\\.,]{8})$#', $thisfile_ape_items_current['data'][0], $matches)) {

						$thisfile_replaygain['album']['peak']       = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!

						$thisfile_replaygain['album']['originator'] = 'unspecified';

						if ($thisfile_replaygain['album']['peak'] <= 0) {

							$this->warning('ReplayGain Album peak from APEtag appears invalid: '.$thisfile_replaygain['album']['peak'].' (original value = "'.$thisfile_ape_items_current['data'][0].'")');

						}

					} else {

						$this->warning('MP3gainAlbumPeak value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'mp3gain_undo':

					if (preg_match('#^[\\-\\+][0-9]{3},[\\-\\+][0-9]{3},[NW]$#', $thisfile_ape_items_current['data'][0])) {

						list($mp3gain_undo_left, $mp3gain_undo_right, $mp3gain_undo_wrap) = explode(',', $thisfile_ape_items_current['data'][0]);

						$thisfile_replaygain['mp3gain']['undo_left']  = intval($mp3gain_undo_left);

						$thisfile_replaygain['mp3gain']['undo_right'] = intval($mp3gain_undo_right);

						$thisfile_replaygain['mp3gain']['undo_wrap']  = (($mp3gain_undo_wrap == 'Y') ? true : false);

					} else {

						$this->warning('MP3gainUndo value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'mp3gain_minmax':

					if (preg_match('#^[0-9]{3},[0-9]{3}$#', $thisfile_ape_items_current['data'][0])) {

						list($mp3gain_globalgain_min, $mp3gain_globalgain_max) = explode(',', $thisfile_ape_items_current['data'][0]);

						$thisfile_replaygain['mp3gain']['globalgain_track_min'] = intval($mp3gain_globalgain_min);

						$thisfile_replaygain['mp3gain']['globalgain_track_max'] = intval($mp3gain_globalgain_max);

					} else {

						$this->warning('MP3gainMinMax value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'mp3gain_album_minmax':

					if (preg_match('#^[0-9]{3},[0-9]{3}$#', $thisfile_ape_items_current['data'][0])) {

						list($mp3gain_globalgain_album_min, $mp3gain_globalgain_album_max) = explode(',', $thisfile_ape_items_current['data'][0]);

						$thisfile_replaygain['mp3gain']['globalgain_album_min'] = intval($mp3gain_globalgain_album_min);

						$thisfile_replaygain['mp3gain']['globalgain_album_max'] = intval($mp3gain_globalgain_album_max);

					} else {

						$this->warning('MP3gainAlbumMinMax value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');

					}

					break;

				case 'tracknumber':

					if (is_array($thisfile_ape_items_current['data'])) {

						foreach ($thisfile_ape_items_current['data'] as $comment) {

							$thisfile_ape['comments']['track_number'][] = $comment;

						}

					}

					break;

				case 'cover art (artist)':

				case 'cover art (back)':

				case 'cover art (band logo)':

				case 'cover art (band)':

				case 'cover art (colored fish)':

				case 'cover art (composer)':

				case 'cover art (conductor)':

				case 'cover art (front)':

				case 'cover art (icon)':

				case 'cover art (illustration)':

				case 'cover art (lead)':

				case 'cover art (leaflet)':

				case 'cover art (lyricist)':

				case 'cover art (media)':

				case 'cover art (movie scene)':

				case 'cover art (other icon)':

				case 'cover art (other)':

				case 'cover art (performance)':

				case 'cover art (publisher logo)':

				case 'cover art (recording)':

				case 'cover art (studio)':

					// list of possible cover arts from https://github.com/mono/taglib-sharp/blob/taglib-sharp-2.0.3.2/src/TagLib/Ape/Tag.cs

					if (is_array($thisfile_ape_items_current['data'])) {

						$this->warning('APEtag "'.$item_key.'" should be flagged as Binary data, but was incorrectly flagged as UTF-8');

						$thisfile_ape_items_current['data'] = implode("\x00", $thisfile_ape_items_current['data']);

					}

					list($thisfile_ape_items_current['filename'], $thisfile_ape_items_current['data']) = explode("\x00", $thisfile_ape_items_current['data'], 2);

					$thisfile_ape_items_current['data_offset'] = $thisfile_ape_items_current['offset'] + strlen($thisfile_ape_items_current['filename']."\x00");

					$thisfile_ape_items_current['data_length'] = strlen($thisfile_ape_items_current['data']);

					do {

						$thisfile_ape_items_current['image_mime'] = '';

						$imageinfo = array();

						$imagechunkcheck = getid3_lib::GetDataImageSize($thisfile_ape_items_current['data'], $imageinfo);

						if (($imagechunkcheck === false) || !isset($imagechunkcheck[2])) {

							$this->warning('APEtag "'.$item_key.'" contains invalid image data');

							break;

						}

						$thisfile_ape_items_current['image_mime'] = image_type_to_mime_type($imagechunkcheck[2]);

						if ($this->inline_attachments === false) {

							// skip entirely

							unset($thisfile_ape_items_current['data']);

							break;

						}

						if ($this->inline_attachments === true) {

							// great

						} elseif (is_int($this->inline_attachments)) {

							if ($this->inline_attachments < $thisfile_ape_items_current['data_length']) {

								// too big, skip

								$this->warning('attachment at '.$thisfile_ape_items_current['offset'].' is too large to process inline ('.number_format($thisfile_ape_items_current['data_length']).' bytes)');

								unset($thisfile_ape_items_current['data']);

								break;

							}

						} elseif (is_string($this->inline_attachments)) {

							$this->inline_attachments = rtrim(str_replace(array('/', '\\'), DIRECTORY_SEPARATOR, $this->inline_attachments), DIRECTORY_SEPARATOR);

							if (!is_dir($this->inline_attachments) || !getID3::is_writable($this->inline_attachments)) {

								// cannot write, skip

								$this->warning('attachment at '.$thisfile_ape_items_current['offset'].' cannot be saved to "'.$this->inline_attachments.'" (not writable)');

								unset($thisfile_ape_items_current['data']);

								break;

							}

						}

						// if we get this far, must be OK

						if (is_string($this->inline_attachments)) {

							$destination_filename = $this->inline_attachments.DIRECTORY_SEPARATOR.md5($info['filenamepath']).'_'.$thisfile_ape_items_current['data_offset'];

							if (!file_exists($destination_filename) || getID3::is_writable($destination_filename)) {

								file_put_contents($destination_filename, $thisfile_ape_items_current['data']);

							} else {

								$this->warning('attachment at '.$thisfile_ape_items_current['offset'].' cannot be saved to "'.$destination_filename.'" (not writable)');

							}

							$thisfile_ape_items_current['data_filename'] = $destination_filename;

							unset($thisfile_ape_items_current['data']);

						} else {

							if (!isset($info['ape']['comments']['picture'])) {

								$info['ape']['comments']['picture'] = array();

							}

							$comments_picture_data = array();

							foreach (array('data', 'image_mime', 'image_width', 'image_height', 'imagetype', 'picturetype', 'description', 'datalength') as $picture_key) {

								if (isset($thisfile_ape_items_current[$picture_key])) {

									$comments_picture_data[$picture_key] = $thisfile_ape_items_current[$picture_key];

								}

							}

							$info['ape']['comments']['picture'][] = $comments_picture_data;

							unset($comments_picture_data);

						}

					} while (false); // @phpstan-ignore-line

					break;

				default:

					if (is_array($thisfile_ape_items_current['data'])) {

						foreach ($thisfile_ape_items_current['data'] as $comment) {

							$thisfile_ape['comments'][strtolower($item_key)][] = $comment;

						}

					}

					break;

			}

		}

		if (empty($thisfile_replaygain)) {

			unset($info['replay_gain']);

		}

		return true;

	}

	/**

	 * @param string $APEheaderFooterData

	 *

	 * @return array|false

	 */

	public function parseAPEheaderFooter($APEheaderFooterData) {

		// http://www.uni-jena.de/~pfk/mpp/sv8/apeheader.html

		// shortcut

		$headerfooterinfo = array();

		$headerfooterinfo['raw'] = array();

		$headerfooterinfo_raw = &$headerfooterinfo['raw'];

		$headerfooterinfo_raw['footer_tag']   =                  substr($APEheaderFooterData,  0, 8);

		if ($headerfooterinfo_raw['footer_tag'] != 'APETAGEX') {

			return false;

		}