<?php
/**
 * Virtual File System: Mime
 *
 * $Id$
 *
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @license PHP License
 * @package WB
 * @subpackage vfs
 */

WBClass::load('WBVFS_Mime');

/**
 * Virtual File System: Mime_Audio
 *
 * Mime handler for audio files. Default file name extension is "mp3"
 * Also all audio files are guessed to be mp3s 
 *
 *
 * @version 0.3.0
 * @package WB
 * @subpackage vfs
 */
class WBVFS_Mime_Audio extends WBVFS_Mime
{
    /**
     * file name extension
     * @var string
     */
    protected $extension = 'mp3';
    
    /**
     * ffmpeg command
     * @link  http://www.ffmpeg.org/
     */
    protected static $ffmpeg  =   'ffmpeg';

    /**
     * Configuration
     * @var WBConfig
     */
    private $config;

    /**
     * initialize tools
     *
     * set command line tools
     */
    public static function staticConstruct()
    {
        self::$ffmpeg           =   WBParam::get('wb/vfs/mime/ffmpeg', self::$ffmpeg);
    }

    /**
     * 2nd constructor
     *
     */
    protected function init()
    {
        $this->config   =   WBClass::create('WBConfig');
        $this->config->load('vfs/transcode/audio');
    }

    /**
     * get information about this file
     *
     * @return array
     */
    public function getInfo()
    {
        $ret    =   null;
        $out    =   array();
        $cmd    =   sprintf('%s -hide_banner -vstats -i %s 2>&1', self::$ffmpeg, $this->file);
        exec($cmd, $out, $ret);

        $this->info =   $this->parseFfprobe($out);
        return $this->info;
    }

    /**
     * Import File
     *
     */
    public function import()
    {
    }
    
    /**
     * Get File Name of Requested File
     *
     * @param bool $redirect whether to redirect
     * @return string
     */
    protected function doGetRequestedFile(&$redirect)
    {
        $this->file =   $this->vfile->getPath();

        $prefix     =   strtolower($this->requestedMimeMinor);
        if (WBVFS::MIME_PLAIN == $prefix) {
            $prefix =   'ogg';
        }

        $this->extension    =   $this->config->get($prefix . '/extension', $prefix);
        if ($prefix == $this->vfile->getMime(WBVFS_File::MIME_MINOR)) {
            return $this->file;
        }

        $this->mimeMinor    =   $this->config->get($prefix . '/mimeminor', $prefix);

        $cacheDir           =   $this->mkCacheDir();
        if (!file_exists($cacheDir . '/' . $prefix)) {
            // this sort of locks the file an prevents multi processings
            touch($cacheDir . '/' . $prefix);
            chmod($cacheDir . '/' . $prefix, 0666);
            $this->transcode($prefix, $cacheDir);
        }
        $this->file         =   $cacheDir . '/' . $prefix;
        return $this->file;
    }

    /**
     * Execute transcoding
     *
     * Set current file to file the one coresponding to requested mime minor type
     * Find matching transcoding targets in config. Populate and execute transcoding
     * commands. If there is a faststart tag, execute post processing command
     *
     * @param string $prefix
     * @param string $cacheDir
     */
    private function transcode($prefix, $cacheDir)
    {
        $now    =   WBClock::now();
        $cwd    =   $this->mkWorkingDir('audio');
        $des    =   'out.' . $prefix;

        // multi or single pass commands
        $cmd        =   $this->config->get($prefix . '/template/cmd', '{FFMPEG} -i {INFILE} -f mp3 -y {OUTFILE} 2>&1');
        if (!is_array($cmd)) {
            $cmd    =   array($cmd);
        }

        $optionA    =   $this->config->get($prefix . '/option/audio', array());
        if (!is_array($optionA)) {
            $optionA    =   trim($optionA);
            if (empty($optionA)) {
                $optionA    =   array();
            }
            else {
                $optionA    =   array($optionA);
            }
        }
        $vars       =   array(
                            'cwd'           =>  $cwd,
                            'presetdir'     =>  WBParam::get('wb/dir/system') . '/resource/mime/video/ffmpeg',
                            'ffmpeg'        =>  self::$ffmpeg,
                            'infile'        =>  $this->file,
                            'outfile'       =>  $des,
                            'option_audio'  =>  implode(' ', $optionA)
                        );

        $oldcwd =   getcwd();
        chdir($cwd);

        // execute all commands
        foreach ($cmd as $c) {
            $c      =   WBString::populate($c, $vars);
            $out    =   array();
            $ret    =   null;
            exec($c, $out, $ret);
            if ($ret > 0) {
                $log    =   array(
                        'file'      =>  basename($this->file),
                        'size'      =>  filesize($this->file),
                        'mime'      =>  'audio',
                        'action'    =>  'convert',
                        'prefix'    =>  $prefix,
                        'cmd'		=>	$c
                    );
                $this->log->err($log);
            }
        }

        rename($des, $cacheDir . '/' . $prefix);

        chdir($oldcwd);
        $this->rmWorkingDir($cwd);

        chmod($cacheDir . '/' . $prefix, 0666);
        $log    =   array(
                        'file'      =>  basename($this->file),
                        'size'      =>  filesize($this->file),
                        'mime'      =>  'audio',
                        'action'    =>  'convert',
                        'target'    =>  $prefix,
                        'elapsed'   =>  WBClock::stop($now, 1000, 1) . 'ms'
        );
        $this->log->notice($log);
    }
}