MessageCache invalidation improvements

[mediawiki.git] / includes / media / MediaTransformOutput.php

<?php
/**
 * Base class for the output of file transformation methods.
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Media
 */

/**
 * Base class for the output of MediaHandler::doTransform() and File::transform().
 *
 * @ingroup Media
 */
abstract class MediaTransformOutput {
        /** @var array Associative array mapping optional supplementary image files
         *  from pixel density (eg 1.5 or 2) to additional URLs.
         */
        public $responsiveUrls = [];

        /** @var File */
        protected $file;

        /** @var int Image width */
        protected $width;

        /** @var int Image height */
        protected $height;

        /** @var string URL path to the thumb */
        protected $url;

        /** @var bool|string */
        protected $page;

        /** @var bool|string Filesystem path to the thumb  */
        protected $path;

        /** @var bool|string Language code, false if not set */
        protected $lang;

        /** @var bool|string Permanent storage path  */
        protected $storagePath = false;

        /**
         * @return int Width of the output box
         */
        public function getWidth() {
                return $this->width;
        }

        /**
         * @return int Height of the output box
         */
        public function getHeight() {
                return $this->height;
        }

        /**
         * @return File
         */
        public function getFile() {
                return $this->file;
        }

        /**
         * Get the final extension of the thumbnail.
         * Returns false for scripted transformations.
         * @return string|bool
         */
        public function getExtension() {
                return $this->path ? FileBackend::extensionFromPath( $this->path ) : false;
        }

        /**
         * @return string|bool The thumbnail URL
         */
        public function getUrl() {
                return $this->url;
        }

        /**
         * @return string|bool The permanent thumbnail storage path
         */
        public function getStoragePath() {
                return $this->storagePath;
        }

        /**
         * @param string $storagePath The permanent storage path
         * @return void
         */
        public function setStoragePath( $storagePath ) {
                $this->storagePath = $storagePath;
                if ( $this->path === false ) {
                        $this->path = $storagePath;
                }
        }

        /**
         * Fetch HTML for this transform output
         *
         * @param array $options Associative array of options. Boolean options
         *     should be indicated with a value of true for true, and false or
         *     absent for false.
         *
         *     alt          Alternate text or caption
         *     desc-link    Boolean, show a description link
         *     file-link    Boolean, show a file download link
         *     custom-url-link    Custom URL to link to
         *     custom-title-link  Custom Title object to link to
         *     valign       vertical-align property, if the output is an inline element
         *     img-class    Class applied to the "<img>" tag, if there is such a tag
         *
         * For images, desc-link and file-link are implemented as a click-through. For
         * sounds and videos, they may be displayed in other ways.
         *
         * @return string
         */
        abstract public function toHtml( $options = [] );

        /**
         * This will be overridden to return true in error classes
         * @return bool
         */
        public function isError() {
                return false;
        }

        /**
         * Check if an output thumbnail file actually exists.
         *
         * This will return false if there was an error, the
         * thumbnail is to be handled client-side only, or if
         * transformation was deferred via TRANSFORM_LATER.
         * This file may exist as a new file in /tmp, a file
         * in permanent storage, or even refer to the original.
         *
         * @return bool
         */
        public function hasFile() {
                // If TRANSFORM_LATER, $this->path will be false.
                // Note: a null path means "use the source file".
                return ( !$this->isError() && ( $this->path || $this->path === null ) );
        }

        /**
         * Check if the output thumbnail is the same as the source.
         * This can occur if the requested width was bigger than the source.
         *
         * @return bool
         */
        public function fileIsSource() {
                return ( !$this->isError() && $this->path === null );
        }

        /**
         * Get the path of a file system copy of the thumbnail.
         * Callers should never write to this path.
         *
         * @return string|bool Returns false if there isn't one
         */
        public function getLocalCopyPath() {
                if ( $this->isError() ) {
                        return false;
                } elseif ( $this->path === null ) {
                        return $this->file->getLocalRefPath(); // assume thumb was not scaled
                } elseif ( FileBackend::isStoragePath( $this->path ) ) {
                        $be = $this->file->getRepo()->getBackend();
                        // The temp file will be process cached by FileBackend
                        $fsFile = $be->getLocalReference( [ 'src' => $this->path ] );

                        return $fsFile ? $fsFile->getPath() : false;
                } else {
                        return $this->path; // may return false
                }
        }

        /**
         * Stream the file if there were no errors
         *
         * @param array $headers Additional HTTP headers to send on success
         * @return Status
         * @since 1.27
         */
        public function streamFileWithStatus( $headers = [] ) {
                if ( !$this->path ) {
                        return Status::newFatal( 'backend-fail-stream', '<no path>' );
                } elseif ( FileBackend::isStoragePath( $this->path ) ) {
                        $be = $this->file->getRepo()->getBackend();
                        return $be->streamFile( [ 'src' => $this->path, 'headers' => $headers ] );
                } else { // FS-file
                        $success = StreamFile::stream( $this->getLocalCopyPath(), $headers );
                        return $success ? Status::newGood() : Status::newFatal( 'backend-fail-stream', $this->path );
                }
        }

        /**
         * Stream the file if there were no errors
         *
         * @deprecated since 1.26, use streamFileWithStatus
         * @param array $headers Additional HTTP headers to send on success
         * @return bool Success
         */
        public function streamFile( $headers = [] ) {
                $this->streamFileWithStatus( $headers )->isOK();
        }

        /**
         * Wrap some XHTML text in an anchor tag with the given attributes
         *
         * @param array $linkAttribs
         * @param string $contents
         * @return string
         */
        protected function linkWrap( $linkAttribs, $contents ) {
                if ( $linkAttribs ) {
                        return Xml::tags( 'a', $linkAttribs, $contents );
                } else {
                        return $contents;
                }
        }

        /**
         * @param string $title
         * @param string|array $params Query parameters to add
         * @return array
         */
        public function getDescLinkAttribs( $title = null, $params = [] ) {
                if ( is_array( $params ) ) {
                        $query = $params;
                } else {
                        $query = [];
                }
                if ( $this->page && $this->page !== 1 ) {
                        $query['page'] = $this->page;
                }
                if ( $this->lang ) {
                        $query['lang'] = $this->lang;
                }

                if ( is_string( $params ) && $params !== '' ) {
                        $query = $params . '&' . wfArrayToCgi( $query );
                }

                $attribs = [
                        'href' => $this->file->getTitle()->getLocalURL( $query ),
                        'class' => 'image',
                ];
                if ( $title ) {
                        $attribs['title'] = $title;
                }

                return $attribs;
        }
}

/**
 * Media transform output for images
 *
 * @ingroup Media
 */
class ThumbnailImage extends MediaTransformOutput {
        /**
         * Get a thumbnail object from a file and parameters.
         * If $path is set to null, the output file is treated as a source copy.
         * If $path is set to false, no output file will be created.
         * $parameters should include, as a minimum, (file) 'width' and 'height'.
         * It may also include a 'page' parameter for multipage files.
         *
         * @param File $file
         * @param string $url URL path to the thumb
         * @param string|bool $path Filesystem path to the thumb
         * @param array $parameters Associative array of parameters
         */
        function __construct( $file, $url, $path = false, $parameters = [] ) {
                # Previous parameters:
                #   $file, $url, $width, $height, $path = false, $page = false

                $defaults = [
                        'page' => false,
                        'lang' => false
                ];

                if ( is_array( $parameters ) ) {
                        $actualParams = $parameters + $defaults;
                } else {
                        # Using old format, should convert. Later a warning could be added here.
                        $numArgs = func_num_args();
                        $actualParams = [
                                'width' => $path,
                                'height' => $parameters,
                                'page' => ( $numArgs > 5 ) ? func_get_arg( 5 ) : false
                        ] + $defaults;
                        $path = ( $numArgs > 4 ) ? func_get_arg( 4 ) : false;
                }

                $this->file = $file;
                $this->url = $url;
                $this->path = $path;

                # These should be integers when they get here.
                # If not, there's a bug somewhere.  But let's at
                # least produce valid HTML code regardless.
                $this->width = round( $actualParams['width'] );
                $this->height = round( $actualParams['height'] );

                $this->page = $actualParams['page'];
                $this->lang = $actualParams['lang'];
        }

        /**
         * Return HTML <img ... /> tag for the thumbnail, will include
         * width and height attributes and a blank alt text (as required).
         *
         * @param array $options Associative array of options. Boolean options
         *     should be indicated with a value of true for true, and false or
         *     absent for false.
         *
         *     alt          HTML alt attribute
         *     title        HTML title attribute
         *     desc-link    Boolean, show a description link
         *     file-link    Boolean, show a file download link
         *     valign       vertical-align property, if the output is an inline element
         *     img-class    Class applied to the \<img\> tag, if there is such a tag
         *     desc-query   String, description link query params
         *     override-width     Override width attribute. Should generally not set
         *     override-height    Override height attribute. Should generally not set
         *     no-dimensions      Boolean, skip width and height attributes (useful if
         *                        set in CSS)
         *     custom-url-link    Custom URL to link to
         *     custom-title-link  Custom Title object to link to
         *     custom target-link Value of the target attribute, for custom-target-link
         *     parser-extlink-*   Attributes added by parser for external links:
         *          parser-extlink-rel: add rel="nofollow"
         *          parser-extlink-target: link target, but overridden by custom-target-link
         *
         * For images, desc-link and file-link are implemented as a click-through. For
         * sounds and videos, they may be displayed in other ways.
         *
         * @throws MWException
         * @return string
         */
        function toHtml( $options = [] ) {
                if ( count( func_get_args() ) == 2 ) {
                        throw new MWException( __METHOD__ . ' called in the old style' );
                }

                $alt = isset( $options['alt'] ) ? $options['alt'] : '';

                $query = isset( $options['desc-query'] ) ? $options['desc-query'] : '';

                $attribs = [
                        'alt' => $alt,
                        'src' => $this->url,
                ];

                if ( !empty( $options['custom-url-link'] ) ) {
                        $linkAttribs = [ 'href' => $options['custom-url-link'] ];
                        if ( !empty( $options['title'] ) ) {
                                $linkAttribs['title'] = $options['title'];
                        }
                        if ( !empty( $options['custom-target-link'] ) ) {
                                $linkAttribs['target'] = $options['custom-target-link'];
                        } elseif ( !empty( $options['parser-extlink-target'] ) ) {
                                $linkAttribs['target'] = $options['parser-extlink-target'];
                        }
                        if ( !empty( $options['parser-extlink-rel'] ) ) {
                                $linkAttribs['rel'] = $options['parser-extlink-rel'];
                        }
                } elseif ( !empty( $options['custom-title-link'] ) ) {
                        /** @var Title $title */
                        $title = $options['custom-title-link'];
                        $linkAttribs = [
                                'href' => $title->getLinkURL(),
                                'title' => empty( $options['title'] ) ? $title->getFullText() : $options['title']
                        ];
                } elseif ( !empty( $options['desc-link'] ) ) {
                        $linkAttribs = $this->getDescLinkAttribs(
                                empty( $options['title'] ) ? null : $options['title'],
                                $query
                        );
                } elseif ( !empty( $options['file-link'] ) ) {
                        $linkAttribs = [ 'href' => $this->file->getUrl() ];
                } else {
                        $linkAttribs = false;
                        if ( !empty( $options['title'] ) ) {
                                $attribs['title'] = $options['title'];
                        }
                }

                if ( empty( $options['no-dimensions'] ) ) {
                        $attribs['width'] = $this->width;
                        $attribs['height'] = $this->height;
                }
                if ( !empty( $options['valign'] ) ) {
                        $attribs['style'] = "vertical-align: {$options['valign']}";
                }
                if ( !empty( $options['img-class'] ) ) {
                        $attribs['class'] = $options['img-class'];
                }
                if ( isset( $options['override-height'] ) ) {
                        $attribs['height'] = $options['override-height'];
                }
                if ( isset( $options['override-width'] ) ) {
                        $attribs['width'] = $options['override-width'];
                }

                // Additional densities for responsive images, if specified.
                // If any of these urls is the same as src url, it'll be excluded.
                $responsiveUrls = array_diff( $this->responsiveUrls, [ $this->url ] );
                if ( !empty( $responsiveUrls ) ) {
                        $attribs['srcset'] = Html::srcSet( $responsiveUrls );
                }

                Hooks::run( 'ThumbnailBeforeProduceHTML', [ $this, &$attribs, &$linkAttribs ] );

                return $this->linkWrap( $linkAttribs, Xml::element( 'img', $attribs ) );
        }
}

/**
 * Basic media transform error class
 *
 * @ingroup Media
 */
class MediaTransformError extends MediaTransformOutput {
        /** @var string HTML formatted version of the error */
        private $htmlMsg;

        /** @var string Plain text formatted version of the error */
        private $textMsg;

        function __construct( $msg, $width, $height /*, ... */ ) {
                $args = array_slice( func_get_args(), 3 );
                $htmlArgs = array_map( 'htmlspecialchars', $args );
                $htmlArgs = array_map( 'nl2br', $htmlArgs );

                $this->htmlMsg = wfMessage( $msg )->rawParams( $htmlArgs )->escaped();
                $this->textMsg = wfMessage( $msg )->rawParams( $htmlArgs )->text();
                $this->width = intval( $width );
                $this->height = intval( $height );
                $this->url = false;
                $this->path = false;
        }

        function toHtml( $options = [] ) {
                return "<div class=\"MediaTransformError\" style=\"" .
                        "width: {$this->width}px; height: {$this->height}px; display:inline-block;\">" .
                        $this->htmlMsg .
                        "</div>";
        }

        function toText() {
                return $this->textMsg;
        }

        function getHtmlMsg() {
                return $this->htmlMsg;
        }

        function isError() {
                return true;
        }
}

/**
 * Shortcut class for parameter validation errors
 *
 * @ingroup Media
 */
class TransformParameterError extends MediaTransformError {
        function __construct( $params ) {
                parent::__construct( 'thumbnail_error',
                        max( isset( $params['width'] ) ? $params['width'] : 0, 120 ),
                        max( isset( $params['height'] ) ? $params['height'] : 0, 120 ),
                        wfMessage( 'thumbnail_invalid_params' )->text() );
        }
}

/**
 * Shortcut class for parameter file size errors
 *
 * @ingroup Media
 * @since 1.25
 */
class TransformTooBigImageAreaError extends MediaTransformError {
        function __construct( $params, $maxImageArea ) {
                $msg = wfMessage( 'thumbnail_toobigimagearea' );

                parent::__construct( 'thumbnail_error',
                        max( isset( $params['width'] ) ? $params['width'] : 0, 120 ),
                        max( isset( $params['height'] ) ? $params['height'] : 0, 120 ),
                        $msg->rawParams(
                                $msg->getLanguage()->formatComputingNumbers(
                                        $maxImageArea, 1000, "size-$1pixel" )
                                )->text()
                        );
        }
}