<?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
 *
 * This Mime handler requires ImageMagick
 *
 * @version 0.7.0
 * @package WB
 * @subpackage vfs
 */
class WBVFS_Mime_Image extends WBVFS_Mime
{
   /**
    * max image size for import
    */
    const IMAGE_SIZE_MAX = 1000;

   /**
    * max image size to resize to
    */
    const IMAGE_RESIZE_MAX = 3000;

   /**
    * max factor to resize images
    */
    const IMAGE_RESIZE_MAX_FACTOR = 5;

    /**
     * Factor for panorama image aspect
     */
    const IMAGE_PANORAMA_DETECT_FACTOR = 3;

    /**
     * Factor for panorama image aspect
     */
    const IMAGE_PANORAMA_RESIZE_MAX_FACTOR = 10;

    /**
     * mogrify command
     * @link http://www.imagemagick.org
     */
    protected static $magickMogrify = 'mogrify';

    /**
     * convert command
     * @link http://www.imagemagick.org
     */
    protected static $magickConvert = 'convert';

    /**
     * rotate image accoring to exif header
     * @var string
     */
    protected static $exifAutotran = 'exifautotran';

    /**
     * too to convert PDFs to images
     */
    protected static $pdftoppm = 'pdftoppm';

    /**
     * ffmpeg command
     */
    protected static $ffmpeg  =   'ffmpeg';

    /**
     * list of mime types that are convertable to image
     *
     * Can convert
     *   - video
     *
     * @var array
     */
    protected $convertable = array(
                            'video',
                            'text',
                            'audio',
                            'application'
                        );

    /**
     * major mime type
     * @var string
     */
    protected $mimeMajor = 'image';

    /**
     * 2nd constructor
     *
     * initialize tools
     */
    protected function init()
    {
        self::$ffmpeg           =   WBParam::get('wb/vfs/mime/ffmpeg', self::$ffmpeg);
        self::$magickMogrify    =   WBParam::get('wb/vfs/mime/imagemagick/mogrify', self::$magickMogrify);
        self::$magickConvert    =   WBParam::get('wb/vfs/mime/imagemagick/convert', self::$magickConvert);
        self::$pdftoppm         =   WBParam::get('wb/vfs/mime/pdftoppm', self::$pdftoppm);
        self::$exifAutotran     =   WBParam::get('wb/vfs/mime/exif/autotran', self::$exifAutotran);
    }

    /**
     * inform when file has been set
     *
     * Resolve file name extension
     * @param string $name
     */
    protected function onSetFile($name = '')
    {
        $this->mimeMajor    =   'image';
        $this->resolveExtension();
    }

    /**
     * inform when virtual file was set
     *
     *
     */
    protected function onSetVirtualFile()
    {
        switch ($this->mimeMajor) {
            case 'image':
                break;
            case 'video':
                $this->mimeMinor    =   'jpeg';
                break;
            default:
                $this->mimeMinor    =   'png';
                break;
        }

        $this->mimeMajor    =   'image';
        $this->resolveExtension();
    }

    /**
     * get information about this file
     *
     * Extract from image:
     *  - width
     *  - height
     *  - par (pixel aspect ration)
     *  - exif header
     *  - panorama mode
     *
     * @return array
     */
    public function getInfo()
    {
        $size       =   getimagesize($this->file);
        $size[0]    =   max(1, $size[0]);
        $size[1]    =   max(1, $size[1]);
        $this->info =   array(
                        'width'     =>  $size[0],
                        'height'    =>  $size[1],
                        'exif'      =>  array(),
                        'panorama'  =>  $this->detectPanoramaMode($size)
                    );

        switch ($this->mimeMinor) {
            case 'jpeg':
            case 'tiff':
                $exif   = @exif_read_data($this->file);
				if (!is_array($exif)) {
					break;
				}

                // remove obvious exif headers
                $exifIgnore =   array('filename', 'filedatetime', 'filesize', 'filetype', 'mimetype', 'computed');
                foreach ($exif as $key => $value) {
                    if (in_array(strtolower($key), $exifIgnore)) {
                        continue;
                    }
                    if (is_scalar($value) && strlen($value) > 1000) {
                        continue;
                    }

                    $this->info['exif'][$key] =   $value;
                }
                break;
        }


        return $this->info;
    }

    /**
     * Detect Panorama Mode by Size
     *
     * @param array $size
     * @return string 'x', 'y' or ''
     */
    private function detectPanoramaMode($size)
    {
        // detect panorama mode
        if ($size[0] > (self::IMAGE_PANORAMA_DETECT_FACTOR * $size[1])) {
            return 'x';
        }
        if ($size[1] > (self::IMAGE_PANORAMA_DETECT_FACTOR * $size[0])) {
            return 'y';
        }
        return '';
    }

    /**
     * execute command
     *
     * Available commands:
     *   - rotate
     *   - flip/flop
     *   - crop
     *   - grayscale
     *   - monochrome
     *
     * @todo implement commands
     * @param string $cmd
     * @param array $arg
     */
    public function execute($cmd, $arg = array())
    {
        $log    =   array(
                'file'      =>  $this->vfile->getId(),
                'mime'      =>  $this->mimeMajor,
                'cmd'       =>  $cmd,
                'status'    =>  'done'
            );
            
        $file   =   WBClass::create('WBFile');
        /** @var $file WBFile */
        $file->tempnam('img');
        $file->copy($this->vfile->getPath() . '.org');

        $cmd    =   trim(strtolower($cmd));
        switch($cmd) {
            case 'rotate':
                $angle  =   intval($arg['angle']) % 360;
                $exe    =   sprintf( '%s -rotate %s %s', self::$magickMogrify, $angle, $file->realpath());
                break;

            case 'grayscale':
                $exe    =   sprintf( '%s -colorspace Gray %s', self::$magickMogrify, $file->realpath());
                break;

            case 'monochrome':
            case 'flip':
            case 'flop':
                $exe    =   sprintf( '%s -%s %s', self::$magickMogrify, $cmd, $file->realpath());
                break;

            default:
                $log['status']  =   'commandunknown';
                $this->log->err($log);
                return;
                break;
        }

        exec($exe, $out, $ret);
        if ($ret > 0) {
            $file->unlink();
            return;
        }
        
        // copy attributes
        $save   =   array(
                'dir'           =>  $this->vfile->getDir(),
                'description'   =>  $this->vfile->getDescription()
            );
        $name   =   $this->vfile->getName();

        // what to do with the orginal?
        switch ($arg['original']) {
            case 'replace':
                copy($file->realpath(), $this->vfile->getPath() . '.org');
                $this->vfile->reimport();
                break;
                
            case 'remove':
                $this->vfile->delete();
                // fall through to create a new VFS file
                
            default:
            case 'copy':
                $new    =   $this->vfile->import($file->realpath(), $name);
                if (!$new->isOK()) {
                    $file->unlink();
                    return;
                }
                $new->save($save);
                $this->vfile    =   $new;
                break;
        }

        $this->log->notice($log);
    }

    /**
     * import file
     *
     * Check whether image extends max-size and resize it
     * Convert non-web-format images to JPEG
     */
    public function import()
    {
        // scalable vector graphic - use the original
        if ('svg+xml' == $this->mimeMinor) {
            return;
        }

        // resize to max size
        $size   =   getimagesize($this->file);

        // build mogrify command
        $cmd    =   array(
                            self::$magickConvert,
                            $this->file,
                            '-strip',
                            '-colorspace sRGB'
                        );

        // resizing image during import increased speed of further image processing
        switch ($this->info['panorama']) {
            case 'x':
                if ($size[1] > self::IMAGE_SIZE_MAX) {
                    $cmd[]  =   '-resize ' . (self::IMAGE_PANORAMA_RESIZE_MAX_FACTOR * self::IMAGE_SIZE_MAX) . 'x' . self::IMAGE_SIZE_MAX;
                }
                break;

            case 'y':
                if ($size[0] > self::IMAGE_SIZE_MAX) {
                    $cmd[]  =   '-resize ' . self::IMAGE_SIZE_MAX . 'x' . (self::IMAGE_PANORAMA_RESIZE_MAX_FACTOR * self::IMAGE_SIZE_MAX);
                }
                break;

            default:
            case '':
                if (max($size[0], $size[1] ) > self::IMAGE_SIZE_MAX) {
                    $cmd[]  =   '-resize ' . self::IMAGE_SIZE_MAX . 'x' . self::IMAGE_SIZE_MAX;
                }
                break;
        }

        // make image format usable for web
        $ext    =   'jpeg';
        switch ($this->mimeMinor) {
            case 'svg+xml':
                // this should never happen - see shortcut above
                return;
                break;

            case 'gif':
            case 'png':
                $ext    =   $this->mimeMinor;
                break;

            case 'jpeg':
                // rotate image according to orientation stored in exif header
                exec(self::$exifAutotran . ' ' . $this->file, $out, $ret);
                break;

            default:
                $cmd[]  =   '-format jpeg';
                $cmd[]  =   '-fill white';
                $cmd[]  =   '-opaque none';
                break;
        }


        $cmd[]  =   $this->file . '.' . $ext;
        $cmd    =   implode(' ', $cmd);
        $log    =   array(
                        'mime'      =>  'image',
                        'action'    =>  'import',
                        'exec'      =>  $cmd
        );
        $this->log->info($log);
        exec($cmd, $out, $ret);


        /*
         *  some image formats like Adobe's Photoshop provide multiple
         *  layers. Mogrify extracts all laysers and converts them
         *  to individual JPEG images. Image #0 represents the merged
         *  layers
         *
         *  Therefore import #0 and trash all layer images
         */
        if (file_exists($this->file . '-0.' . $ext)) {
            rename($this->file . '-0.' . $ext, $this->file);
            exec('rm ' . $this->file . '-*');
            return;
        }

        // remove extension
        if (file_exists($this->file . '.' . $ext)) {
            rename($this->file . '.' . $ext, $this->file);
        }

        return;
    }

    /**
     * get file name of requested file
     *
     * @return string
     */
    protected function doGetRequestedFile(&$redirect)
    {
        $this->incrementable    =   false;

        $this->file =   $this->vfile->getPath();
        $major      =   $this->vfile->getMime(WBVFS_File::MIME_MAJOR);
        $minor      =   $this->vfile->getMime(WBVFS_File::MIME_MINOR);
        switch ($major) {
            case 'image':
                $org                =   array($this->vfile->getInfo('width'), $this->vfile->getInfo('height'));
                $this->mimeMinor    =   $minor;

                // just deliver file, don't resize, because it is scalable anyway
                if ('svg+xml' == $minor) {
                    return $this->file;
                }
                break;

            case 'video':
                $org                =   array($this->vfile->getInfo('width'), $this->vfile->getInfo('height'));
                $this->convertVideo($org);
                break;

            case 'application':
                if ($this->convertApplication($minor, $org)) {
                    break;
                }

            default;
                $org            =   array(64, 64);
                $this->file     =   $this->getIcon($major, $this->vfile->getMime(WBVFS_File::MIME_MINOR));
                break;
        }

        // increment view counter
        if ($this->resize($org, $redirect) && $major == 'image') {
            // only for real images
            $size   =   explode('x', $this->req->get('size', ''));

            if (!count($size) == 2 || !is_numeric($size[0]) || !is_numeric($size[1])) {
                $size   =   $org;
            }

            // must have resonable size, like 300x300
            $res    =   array(300, 300);

            // for small images, half of the image's file is suffice
            if ($org[0] < $res[0]) {
                $res[0] =   floor($org[0] / 2);
            }
            if ($org[1] < $res[1]) {
                $res[1] =   floor($org[1] / 2);
            }

            if ($res[0] < $size[0] && $res[1] < $size[1]) {
                $this->incrementable    =   true;
            }

        }
        $this->resolveExtension();
        return $this->file;
    }

    /**
     * tell file name extension
     *
     * Calculate suitable file name extension accotding
     * to minor mime type
     */
    protected function resolveExtension()
    {
        // figure out file extension
        switch ($this->mimeMinor) {
            case 'svg+xml':
                $this->extension    =   'svg';
                break;
            case 'png':
                $this->extension    =   'png';
                break;
            case 'gif':
                $this->extension    =   'gif';
                break;
            default:
            case 'jpg':
                $this->extension    =   'jpg';
                break;
        }
    }

    /**
     * get path of icon
     *
     * try to find icon path for mime type
     *
     * @param string $major
     * @param string $minor
     * @return string
     */
    protected function getIcon($major, $minor)
    {
        $this->mimeMinor    =   'png';
        $this->resolveExtension();

        // application icons
        if ($major == 'application') {
            $icon   =   $major . '-' . $minor;
            $file   =   WBParam::get('wb/dir/base')
                    . '/resource/mime/icon/'
                    . $icon
                    . '.png';
            if (!file_exists($file)) {
                $file   =   WBParam::get('wb/dir/system')
                        . '/resource/mime/icon/'
                        . $icon
                        . '.png';
            }
            if (file_exists($file)) {
                return $file;
            }
        }

        // icons by major mime type
        $icon       =   $major;
        if (!in_array($major, array('text', 'audio', 'application'))) {
            $icon   =   'unknown';
        }

        // get icon for major mime type
        $file   =   WBParam::get('wb/dir/base')
                . '/resource/mime/icon/'
                . $icon
                . '.png';
        if (!file_exists($file)) {
            $file   =   WBParam::get('wb/dir/system')
                    . '/resource/mime/icon/'
                    . $icon
                    . '.png';
        }
        return $file;
    }

    /**
     * Convert application/* to image
     *
     * Some application file are convertable to images. Support for the
     * the following sub-mime-types:
     *  - pdf
     * @param string $minor
     * @param array $org
     * @return bool true if mime type is convertable
     */
    private function convertApplication($minor, &$org)
    {
        if ('pdf' != $minor) {
            return false;
        }

        $org        =   array();
        $cacheDir   =   $this->mkCacheDir();

        // convert PDF to png
        if (!file_exists($cacheDir . '/image.jpg')) {
            $cmd    =   array(self::$pdftoppm);
            //$cmd[]  =   '-jpeg';
            $cmd[]  =   '-f 1';
            $cmd[]  =   '-l 1';
            $cmd[]  =   $this->file;
            $cmd[]  =   $cacheDir . '/image';
            $cmd    =   implode(' ', $cmd);
            $log    =   array(
                            'mime'      =>  'image',
                            'action'    =>  'convert-pdf',
                            'exec'      =>  $cmd
            );
            $this->log->info($log);
            exec($cmd, $out, $ret);

            // depending on the amount of pages, zero or more "0" will be added to the filename
            for ($i = 0; $i < 5; ++$i) {
                $imageFilename  =   $cacheDir . '/image-'. str_repeat('0', $i) .'1.ppm';
                if (file_exists($imageFilename)) {
                    rename($imageFilename, $cacheDir . '/image.ppm');
                    break;
                }
            }

            $cmd    =   array(self::$magickMogrify);
            $cmd[]  =   '-format jpeg';
            $cmd[]  =   $cacheDir . '/image.ppm';
            $cmd    =   implode(' ', $cmd);

            $log    =   array(
                            'mime'      =>  'image',
                            'action'    =>  'convert-pdf',
                            'exec'      =>  $cmd
                        );
            $this->log->info($log);
            exec($cmd, $out, $ret);

            if (file_exists($cacheDir . '/image.jpeg')) {
                rename($cacheDir . '/image.jpeg', $cacheDir . '/image.jpg');
            }

            unlink($cacheDir . '/image.ppm');

            $size   =   getimagesize($cacheDir . '/image.jpg');
            if (max(intval($size[0]), intval($size[1])) > self::IMAGE_SIZE_MAX) {
                $cmd    =   array(self::$magickMogrify);
                $cmd[]  =   '-resize ' . self::IMAGE_SIZE_MAX . 'x' . self::IMAGE_SIZE_MAX;
                $cmd[]  =   $cacheDir . '/image.jpg';
                $cmd    =   implode(' ', $cmd);
                $log    =   array(
                                'mime'      =>  'image',
                                'action'    =>  'convert-pdf-resize',
                                'exec'      =>  $cmd
                );
                $this->log->info($log);
                exec($cmd, $out, $ret);
            }
        }

        $this->file =   $cacheDir . '/image.jpg';

        $size   =   getimagesize($this->file);
        $org    =   array($size[0], $size[1]);
        return true;
    }

    /**
     * convert video to browser compatible image
     *
     * Either convert to animation or to sinplge image
     *
     * @param array $org original size
     * @return bool true on success
     */
    public function convertVideo($org)
    {
        $target =   'image';

        $now    =   WBClock::now();
        $log    =   array(
                        'mime'      =>  'image',
                        'action'    =>  'convert',
                        'source'    =>  'video',
                        'cache'     =>  'hit',
                        'elapsed'   =>  '0ms'
            );
        $cacheDir   =   $this->mkCacheDir();
        if (file_exists($cacheDir . '/' . $target) && filesize($cacheDir . '/' . $target) > 10) {
            $this->file =   $cacheDir . '/' . $target;
            $this->mimeMinor    =   'jpeg';
            if ($target == 'anim') {
                $this->mimeMinor    =   'gif';
            }
            $log['elapsed']     =   WBClock::stop($now, 1000, 1) . 'ms';
            $this->log->notice($log);
            return true;
        }

        // this sort of locks the file an prevents multi processings
        touch($cacheDir . '/' . $target, null);
        chmod($cacheDir . '/' . $target, 0666);

        // build preview
        if ($target == 'anim') {
            $image  =   $this->convertVideo2Anim($org);
        } else {
            $image  =   $this->convertVideo2Image($org);
        }

        $this->file =   $cacheDir . '/' . $target;
        $this->mimeMinor    =   'jpeg';
        if ($target == 'anim') {
            $this->mimeMinor    =   'gif';
        }
        $this->resolveExtension();

        rename($image, $this->file);
        chmod($this->file, 0666);

        $log['elapsed']     =   WBClock::stop($now, 1000, 1) . 'ms';
        $log['cache']       =   'miss';
        $this->log->notice($log);

    }

    /**
     * extract simple image from video
     *
     * @param array $org original size
     * @return string image file name
     */
    public function convertVideo2Image($org)
    {
        $tmpDir =   WBParam::get('wb/dir/base') . '/var/tmp';
        $image  =   tempnam($tmpDir, 'vfsVideoImage');

        $seconds    =   array(100, 50, 20, 5, 1, 0);
        $cmd        =  '%s -i %s -ss %%d -an -vframes 1 -f image2 -y %s 2>&1';
        $cmd        =  sprintf($cmd, self::$ffmpeg, $this->file, $image);

        foreach ($seconds as $sec) {
            if ($sec > $this->vfile->getInfo('seconds')) {
                continue;
            }

            $out    =   array();
            $ret    =   null;
            exec(sprintf($cmd, $sec), $out, $ret);
            if(filesize($image)) {
                exec(self::$magickMogrify . ' -resize ' . implode('x', $org) . '! ' . $image);
                return $image;
            }
            clearstatcache();
        }

        // shis should never happen!
        unlink($image);
        return $image;
    }

    /**
     * build an animated gif as preview for viedeo
     *
     * Extract frames after X second of the movie. Use every 25th
     * frame to build a preview animatrion.
     *
     * @param array $org original size
     * @return string image file name
     */
    public function convertVideo2Anim($org)
    {
        $tmpDir =   WBParam::get('wb/dir/base') . '/var/tmp';
        $image  =   tempnam($tmpDir, 'vfsVideoAnim');

        $seconds    =   array(100, 50, 20, 5, 1);
        foreach ($seconds as $sec) {
            if ($this->vfile->getInfo('seconds') > ($sec + 40)) {
                break;
            }
        }

        // extract some frames
        $cmd        =  '%s -i %s -ss %d -an -r 0.25 -vframes 10 -f image2 %s%%2d.jpg 2>&1';
        $cmd        =  sprintf($cmd, self::$ffmpeg, $this->file, $sec, $image);
        exec($cmd, $out, $ret);

        // join frame to animated gif
        $cmd    =   '%s -resize %s! -adjoin -delay 100 %s*.jpg %s.gif';
        $cmd    =  sprintf($cmd, self::$magickConvert, implode('x', $org), $image, $image);
        exec($cmd, $out, $ret);

        // remove temporary files
        $cmd    =   'rm -f %s*.jpg';
        $cmd    =  sprintf($cmd, $image);
        exec($cmd, $out, $ret);
        unlink($image);

        return $image . '.gif';
    }

    /**
     * change image to requested size
     *
     * Return true in case the file will be delivered, false on redirect
     *
     * @param array $redirect parameter
     * @return bool
     */
    protected function resize($org, &$redirect)
    {
        $size   =   explode('x', $this->req->get('size', ''));

        // shortcut if no size or invalid parameter
        if (count($size) != 2 || !is_numeric($size[0]) || !is_numeric($size[1])) {
            return true;
        }

        if (!$this->calcSize($size, $org)) {
            $redirect   =   array(
                                'get'   =>  array(
                                    'size'  =>  implode('x', $size)
                                )
                        );
            return false;
        }

        $size       =   implode('x', $size);
        $cacheDir   =   $this->mkCacheDir();
        $cacheFile  =   $cacheDir . '/' . $size;
        $now        =   WBClock::now();
        if (!file_exists($cacheFile)) {
            // resize image and cache it
            copy($this->file, $cacheFile);
            exec(self::$magickMogrify . ' -resize ' . $size . ' ' . $cacheFile);
            $log    =   array(
                        'mime'      =>  'image',
                        'action'    =>  'resize',
                        'size'      =>  $size,
                        'elapsed'   =>  WBClock::stop($now, 1000, 1) . 'ms'
                );
            $this->log->notice($log);
        }

        $this->file =   $cacheFile;
        return true;
    }

    /**
     * caluclate new image size
     *
     * calculate proper image size and resize factor while
     * keeping aspect.
     *
     * The reckoned width and height are stored in size-array
     *
     * In case the requested size is too far away from the calculated size,
     * it will return false to indicate that you better redirect
     *
     * @param array $size requested image size
     * @param array $org
     * @return true on success
     */
    protected function calcSize(&$size, $org)
    {
        $tmp    =   array();
        $tmp[0] =   min($size[0], self::IMAGE_RESIZE_MAX);
        $tmp[1] =   min($size[1], self::IMAGE_RESIZE_MAX);

        $panorama   =   $this->detectPanoramaMode($org);
        switch ($panorama) {
            case 'x':
                $tmp[0] =   min($size[0], (self::IMAGE_PANORAMA_RESIZE_MAX_FACTOR * self::IMAGE_RESIZE_MAX));
                break;

            case 'y':
                $tmp[1] =   min($size[1], (self::IMAGE_PANORAMA_RESIZE_MAX_FACTOR * self::IMAGE_RESIZE_MAX));
                break;

            default:
                break;
        }

        // get resize factor
        $divX   =   $tmp[0] / $org[0];
        $divY   =   $tmp[1] / $org[1];
        $factor =   min($divX, $divY, self::IMAGE_RESIZE_MAX_FACTOR);

        // make sure there is at least one pixel in width and height
        $x      =   max(1, round($org[0] * $factor));
        $y      =   max(1, round($org[1] * $factor));

        // this is the excact result
        if ($x == $size[0] && $y == $size[1]) {
            return true;
        }

        // be somewhat tolerant to avoid too many redirects
        if (abs($x - $tmp[0]) < 3 && abs($y - $tmp[1]) < 3) {
            $size[0]    = $x;
            $size[1]    = $y;
            return true;
        }

        // this is the new image size
        $size[0]    = $x;
        $size[1]    = $y;
        return false;
    }
}