/wp-content/plugins/jetpack/class.photon.php

<?php



class Jetpack_Photon {

	/**

	 * Class variables

	 */

	// Oh look, a singleton

	private static $__instance = null;



	// Allowed extensions must match http://code.trac.wordpress.org/browser/photon/index.php#L31

	protected static $extensions = array(

		'gif',

		'jpg',

		'jpeg',

		'png'

	);



	// Don't access this directly. Instead, use self::image_sizes() so it's actually populated with something.

	protected static $image_sizes = null;



	/**

	 * Singleton implementation

	 *

	 * @return object

	 */

	public static function instance() {

		if ( ! is_a( self::$__instance, 'Jetpack_Photon' ) ) {

			self::$__instance = new Jetpack_Photon;

			self::$__instance->setup();

		}



		return self::$__instance;

	}



	/**

	 * Silence is golden.

	 */

	private function __construct() {}



	/**

	 * Register actions and filters, but only if basic Photon functions are available.

	 * The basic functions are found in ./functions.photon.php.

	 *

	 * @uses add_action, add_filter

	 * @return null

	 */

	private function setup() {

		// Display warning if site is private

		add_action( 'jetpack_activate_module_photon', array( $this, 'action_jetpack_activate_module_photon' ) );



		if ( ! function_exists( 'jetpack_photon_url' ) )

			return;



		// Images in post content and galleries

		add_filter( 'the_content', array( __CLASS__, 'filter_the_content' ), 999999 );

		add_filter( 'get_post_galleries', array( __CLASS__, 'filter_the_galleries' ), 999999 );



		// Core image retrieval

		add_filter( 'image_downsize', array( $this, 'filter_image_downsize' ), 10, 3 );



		// Helpers for maniuplated images

		add_action( 'wp_enqueue_scripts', array( $this, 'action_wp_enqueue_scripts' ), 9 );

	}



	/**

	 * Check if site is private and warn user if it is

	 *

	 * @uses Jetpack::check_privacy

	 * @action jetpack_activate_module_photon

	 * @return null

	 */

	public function action_jetpack_activate_module_photon() {

		Jetpack::check_privacy( __FILE__ );

	}



	/**

	 ** IN-CONTENT IMAGE MANIPULATION FUNCTIONS

	 **/



	/**

	 * Match all images and any relevant <a> tags in a block of HTML.

	 *

	 * @param string $content Some HTML.

	 * @return array An array of $images matches, where $images[0] is

	 *         an array of full matches, and the link_url, img_tag,

	 *         and img_url keys are arrays of those matches.

	 */

	public static function parse_images_from_html( $content ) {

		$images = array();



		if ( preg_match_all( '#(?:<a[^>]+?href=["|\'](?P<link_url>[^\s]+?)["|\'][^>]*?>\s*)?(?P<img_tag><img[^>]+?src=["|\'](?P<img_url>[^\s]+?)["|\'].*?>){1}(?:\s*</a>)?#is', $content, $images ) ) {

			foreach ( $images as $key => $unused ) {

				// Simplify the output as much as possible, mostly for confirming test results.

				if ( is_numeric( $key ) && $key > 0 )

					unset( $images[$key] );

			}



			return $images;

		}



		return array();

	}



	/**

	 * Try to determine height and width from strings WP appends to resized image filenames.

	 *

	 * @param string $src The image URL.

	 * @return array An array consisting of width and height.

	 */

	public static function parse_dimensions_from_filename( $src ) {

		$width_height_string = array();



		if ( preg_match( '#-(\d+)x(\d+)\.(?:' . implode('|', self::$extensions ) . '){1}$#i', $src, $width_height_string ) ) {

			$width = (int) $width_height_string[1];

			$height = (int) $width_height_string[2];



			if ( $width && $height )

				return array( $width, $height );

		}



		return array( false, false );

	}



	/**

	 * Identify images in post content, and if images are local (uploaded to the current site), pass through Photon.

	 *

	 * @param string $content

	 * @uses self::validate_image_url, apply_filters, jetpack_photon_url, esc_url

	 * @filter the_content

	 * @return string

	 */

	public static function filter_the_content( $content ) {

		$images = Jetpack_Photon::parse_images_from_html( $content );



		if ( ! empty( $images ) ) {

			$content_width = Jetpack::get_content_width();



			$image_sizes = self::image_sizes();

			$upload_dir = wp_upload_dir();



			foreach ( $images[0] as $index => $tag ) {

				// Default to resize, though fit may be used in certain cases where a dimension cannot be ascertained

				$transform = 'resize';



				// Start with a clean attachment ID each time

				$attachment_id = false;



				// Flag if we need to munge a fullsize URL

				$fullsize_url = false;



				// Identify image source

				$src = $src_orig = $images['img_url'][ $index ];



				// Allow specific images to be skipped

				if ( apply_filters( 'jetpack_photon_skip_image', false, $src, $tag ) )

					continue;



				// Support Automattic's Lazy Load plugin

				// Can't modify $tag yet as we need unadulterated version later

				if ( preg_match( '#data-lazy-src=["|\'](.+?)["|\']#i', $images['img_tag'][ $index ], $lazy_load_src ) ) {

					$placeholder_src = $placeholder_src_orig = $src;

					$src = $src_orig = $lazy_load_src[1];

				} elseif ( preg_match( '#data-lazy-original=["|\'](.+?)["|\']#i', $images['img_tag'][ $index ], $lazy_load_src ) ) {

					$placeholder_src = $placeholder_src_orig = $src;

					$src = $src_orig = $lazy_load_src[1];

				}



				// Check if image URL should be used with Photon

				if ( self::validate_image_url( $src ) ) {

					// Find the width and height attributes

					$width = $height = false;



					// First, check the image tag

					if ( preg_match( '#width=["|\']?([\d%]+)["|\']?#i', $images['img_tag'][ $index ], $width_string ) )

						$width = $width_string[1];



					if ( preg_match( '#height=["|\']?([\d%]+)["|\']?#i', $images['img_tag'][ $index ], $height_string ) )

						$height = $height_string[1];



					// Can't pass both a relative width and height, so unset the height in favor of not breaking the horizontal layout.

					if ( false !== strpos( $width, '%' ) && false !== strpos( $height, '%' ) )

						$width = $height = false;



					// Detect WP registered image size from HTML class

					if ( preg_match( '#class=["|\']?[^"\']*size-([^"\'\s]+)[^"\']*["|\']?#i', $images['img_tag'][ $index ], $size ) ) {

						$size = array_pop( $size );



						if ( false === $width && false === $height && 'full' != $size && array_key_exists( $size, $image_sizes ) ) {

							$width = (int) $image_sizes[ $size ]['width'];

							$height = (int) $image_sizes[ $size ]['height'];

							$transform = $image_sizes[ $size ]['crop'] ? 'resize' : 'fit';

						}

					} else {

						unset( $size );

					}



					// WP Attachment ID, if uploaded to this site

					if ( preg_match( '#class=["|\']?[^"\']*wp-image-([\d]+)[^"\']*["|\']?#i', $images['img_tag'][ $index ], $attachment_id ) && ( 0 === strpos( $src, $upload_dir['baseurl'] ) || apply_filters( 'jetpack_photon_image_is_local', false, compact( 'src', 'tag', 'images', 'index' ) ) ) ) {

						$attachment_id = intval( array_pop( $attachment_id ) );



						if ( $attachment_id ) {

							$attachment = get_post( $attachment_id );



							// Basic check on returned post object

							if ( is_object( $attachment ) && ! is_wp_error( $attachment ) && 'attachment' == $attachment->post_type ) {

								$src_per_wp = wp_get_attachment_image_src( $attachment_id, isset( $size ) ? $size : 'full' );



								if ( self::validate_image_url( $src_per_wp[0] ) ) {

									$src = $src_per_wp[0];

									$fullsize_url = true;



									// Prevent image distortion if a detected dimension exceeds the image's natural dimensions

									if ( ( false !== $width && $width > $src_per_wp[1] ) || ( false !== $height && $height > $src_per_wp[2] ) ) {

										$width = false == $width ? false : min( $width, $src_per_wp[1] );

										$height = false == $height ? false : min( $height, $src_per_wp[2] );

									}



									// If no width and height are found, max out at source image's natural dimensions

									// Otherwise, respect registered image sizes' cropping setting

									if ( false == $width && false == $height ) {

										$width = $src_per_wp[1];

										$height = $src_per_wp[2];

										$transform = 'fit';

									} elseif ( isset( $size ) && array_key_exists( $size, $image_sizes ) && isset( $image_sizes[ $size ]['crop'] ) ) {

										$transform = (bool) $image_sizes[ $size ]['crop'] ? 'resize' : 'fit';

									}

								}

							} else {

								unset( $attachment_id );

								unset( $attachment );

							}

						}

					}



					// If image tag lacks width and height arguments, try to determine from strings WP appends to resized image filenames.

					if ( false === $width && false === $height ) {

						list( $width, $height ) = Jetpack_Photon::parse_dimensions_from_filename( $src );

					}



					// If width is available, constrain to $content_width

					if ( false !== $width && false === strpos( $width, '%' ) && is_numeric( $content_width ) ) {

						if ( $width > $content_width && false !== $height && false === strpos( $height, '%' ) ) {

							$height = round( ( $content_width * $height ) / $width );

							$width = $content_width;

						} elseif ( $width > $content_width ) {

							$width = $content_width;

						}

					}



					// Set a width if none is found and $content_width is available

					// If width is set in this manner and height is available, use `fit` instead of `resize` to prevent skewing

					if ( false === $width && is_numeric( $content_width ) ) {

						$width = (int) $content_width;



						if ( false !== $height )

							$transform = 'fit';

					}



					// Detect if image source is for a custom-cropped thumbnail and prevent further URL manipulation.

					if ( ! $fullsize_url && preg_match_all( '#-e[a-z0-9]+(-\d+x\d+)?\.(' . implode('|', self::$extensions ) . '){1}$#i', basename( $src ), $filename ) )

						$fullsize_url = true;



					// Build URL, first maybe removing WP's resized string so we pass the original image to Photon

					if ( ! $fullsize_url ) {

						$src = self::strip_image_dimensions_maybe( $src );

					}



					// Build array of Photon args and expose to filter before passing to Photon URL function

					$args = array();



					if ( false !== $width && false !== $height && false === strpos( $width, '%' ) && false === strpos( $height, '%' ) )

						$args[ $transform ] = $width . ',' . $height;

					elseif ( false !== $width )

						$args['w'] = $width;

					elseif ( false !== $height )

						$args['h'] = $height;



					$args = apply_filters( 'jetpack_photon_post_image_args', $args, compact( 'tag', 'src', 'src_orig', 'width', 'height' ) );



					$photon_url = jetpack_photon_url( $src, $args );



					// Modify image tag if Photon function provides a URL

					// Ensure changes are only applied to the current image by copying and modifying the matched tag, then replacing the entire tag with our modified version.

					if ( $src != $photon_url ) {

						$new_tag = $tag;



						// If present, replace the link href with a Photoned URL for the full-size image.

						if ( ! empty( $images['link_url'][ $index ] ) && self::validate_image_url( $images['link_url'][ $index ] ) )

							$new_tag = preg_replace( '#(href=["|\'])' . $images['link_url'][ $index ] . '(["|\'])#i', '\1' . jetpack_photon_url( $images['link_url'][ $index ] ) . '\2', $new_tag, 1 );



						// Supplant the original source value with our Photon URL

						$photon_url = esc_url( $photon_url );

						$new_tag = str_replace( $src_orig, $photon_url, $new_tag );



						// If Lazy Load is in use, pass placeholder image through Photon

						if ( isset( $placeholder_src ) && self::validate_image_url( $placeholder_src ) ) {

							$placeholder_src = jetpack_photon_url( $placeholder_src );



							if ( $placeholder_src != $placeholder_src_orig )

								$new_tag = str_replace( $placeholder_src_orig, esc_url( $placeholder_src ), $new_tag );



							unset( $placeholder_src );

						}



						// Remove the width and height arguments from the tag to prevent distortion

						$new_tag = preg_replace( '#(?<=\s)(width|height)=["|\']?[\d%]+["|\']?\s?#i', '', $new_tag );



						// Tag an image for dimension checking

						$new_tag = preg_replace( '#(\s?/)?>(\s*</a>)?$#i', ' data-recalc-dims="1"\1>\2', $new_tag );



						// Replace original tag with modified version

						$content = str_replace( $tag, $new_tag, $content );

					}

				} elseif ( preg_match( '#^http(s)?://i[\d]{1}.wp.com#', $src ) && ! empty( $images['link_url'][ $index ] ) && self::validate_image_url( $images['link_url'][ $index ] ) ) {

					$new_tag = preg_replace( '#(href=["|\'])' . $images['link_url'][ $index ] . '(["|\'])#i', '\1' . jetpack_photon_url( $images['link_url'][ $index ] ) . '\2', $tag, 1 );



					$content = str_replace( $tag, $new_tag, $content );

				}

			}

		}



		return $content;

	}



	public static function filter_the_galleries( $galleries ) {

		if ( empty( $galleries ) || ! is_array( $galleries ) ) {

			return $galleries;

		}



		// Pass by reference, so we can modify them in place.

		foreach ( $galleries as &$this_gallery ) {

			if ( is_string( $this_gallery ) ) {

				$this_gallery = self::filter_the_content( $this_gallery );

		// LEAVING COMMENTED OUT as for the moment it doesn't seem

		// necessary and I'm not sure how it would propagate through.

		//	} elseif ( is_array( $this_gallery )

		//	           && ! empty( $this_gallery['src'] )

		//	           && ! empty( $this_gallery['type'] )

		//	           && in_array( $this_gallery['type'], array( 'rectangle', 'square', 'circle' ) ) ) {

		//		$this_gallery['src'] = array_map( 'jetpack_photon_url', $this_gallery['src'] );

			}

		}

		unset( $this_gallery ); // break the reference.



		return $galleries;

	}



	/**

	 ** CORE IMAGE RETRIEVAL

	 **/



	/**

	 * Filter post thumbnail image retrieval, passing images through Photon

	 *

	 * @param string|bool $image

	 * @param int $attachment_id

	 * @param string|array $size

	 * @uses is_admin, apply_filters, wp_get_attachment_url, self::validate_image_url, this::image_sizes, jetpack_photon_url

	 * @filter image_downsize

	 * @return string|bool

	 */

	public function filter_image_downsize( $image, $attachment_id, $size ) {

		// Don't foul up the admin side of things, and provide plugins a way of preventing Photon from being applied to images.

		if ( is_admin() || apply_filters( 'jetpack_photon_override_image_downsize', false, compact( 'image', 'attachment_id', 'size' ) ) )

			return $image;



		// Get the image URL and proceed with Photon-ification if successful

		$image_url = wp_get_attachment_url( $attachment_id );



		if ( $image_url ) {

			// Check if image URL should be used with Photon

			if ( ! self::validate_image_url( $image_url ) )

				return $image;



			// If an image is requested with a size known to WordPress, use that size's settings with Photon

			if ( ( is_string( $size ) || is_int( $size ) ) && array_key_exists( $size, self::image_sizes() ) ) {

				$image_args = self::image_sizes();

				$image_args = $image_args[ $size ];



				$photon_args = array();



				// `full` is a special case in WP

				// To ensure filter receives consistent data regardless of requested size, `$image_args` is overridden with dimensions of original image.

				if ( 'full' == $size ) {

					$image_meta = wp_get_attachment_metadata( $attachment_id );

					if ( isset( $image_meta['width'], $image_meta['height'] ) ) {

						// 'crop' is true so Photon's `resize` method is used

						$image_args = array(

							'width'  => $image_meta['width'],

							'height' => $image_meta['height'],

							'crop'   => true

						);

					}

				}



				// Expose determined arguments to a filter before passing to Photon

				$transform = $image_args['crop'] ? 'resize' : 'fit';



				// Check specified image dimensions and account for possible zero values; photon fails to resize if a dimension is zero.

				if ( 0 == $image_args['width'] || 0 == $image_args['height'] ) {

					if ( 0 == $image_args['width'] && 0 < $image_args['height'] ) {

						$photon_args['h'] = $image_args['height'];

					} elseif ( 0 == $image_args['height'] && 0 < $image_args['width'] ) {

						$photon_args['w'] = $image_args['width'];

					}

				} else {

					if ( ( 'resize' === $transform ) && $image_meta = wp_get_attachment_metadata( $attachment_id ) ) {

						// Lets make sure that we don't upscale images since wp never upscales them as well

						$smaller_width  = ( ( $image_meta['width']  < $image_args['width']  ) ? $image_meta['width']  : $image_args['width']  );

						$smaller_height = ( ( $image_meta['height'] < $image_args['height'] ) ? $image_meta['height'] : $image_args['height'] );



						$photon_args[ $transform ] = $smaller_width . ',' . $smaller_height;

					} else {

						$photon_args[ $transform ] = $image_args['width'] . ',' . $image_args['height'];

					}



				}



				$photon_args = apply_filters( 'jetpack_photon_image_downsize_string', $photon_args, compact( 'image_args', 'image_url', 'attachment_id', 'size', 'transform' ) );



				// Generate Photon URL

				$image = array(

					jetpack_photon_url( $image_url, $photon_args ),

					false,

					false

				);

			} elseif ( is_array( $size ) ) {

				// Pull width and height values from the provided array, if possible

				$width = isset( $size[0] ) ? (int) $size[0] : false;

				$height = isset( $size[1] ) ? (int) $size[1] : false;



				// Don't bother if necessary parameters aren't passed.

				if ( ! $width || ! $height )

					return $image;



				// Expose arguments to a filter before passing to Photon

				$photon_args = array(

					'fit' => $width . ',' . $height

				);



				$photon_args = apply_filters( 'jetpack_photon_image_downsize_array', $photon_args, compact( 'width', 'height', 'image_url', 'attachment_id' ) );



				// Generate Photon URL

				$image = array(

					jetpack_photon_url( $image_url, $photon_args ),

					false,

					false

				);

			}

		}



		return $image;

	}



	/**

	 ** GENERAL FUNCTIONS

	 **/



	/**

	 * Ensure image URL is valid for Photon.

	 * Though Photon functions address some of the URL issues, we should avoid unnecessary processing if we know early on that the image isn't supported.

	 *

	 * @param string $url

	 * @uses wp_parse_args

	 * @return bool

	 */

	protected static function validate_image_url( $url ) {

		$parsed_url = @parse_url( $url );



		if ( ! $parsed_url )

			return false;



		// Parse URL and ensure needed keys exist, since the array returned by `parse_url` only includes the URL components it finds.

		$url_info = wp_parse_args( $parsed_url, array(

			'scheme' => null,

			'host'   => null,

			'port'   => null,

			'path'   => null

		) );



		// Bail if scheme isn't http or port is set that isn't port 80

		if ( ( 'http' != $url_info['scheme'] || ! in_array( $url_info['port'], array( 80, null ) ) ) && apply_filters( 'jetpack_photon_reject_https', true ) )

			return false;



		// Bail if no host is found

		if ( is_null( $url_info['host'] ) )

			return false;



		// Bail if the image alredy went through Photon

		if ( preg_match( '#^i[\d]{1}.wp.com$#i', $url_info['host'] ) )

			return false;



		// Bail if no path is found

		if ( is_null( $url_info['path'] ) )

			return false;



		// Ensure image extension is acceptable

		if ( ! in_array( strtolower( pathinfo( $url_info['path'], PATHINFO_EXTENSION ) ), self::$extensions ) )

			return false;



		// If we got this far, we should have an acceptable image URL

		// But let folks filter to decline if they prefer.

		return apply_filters( 'photon_validate_image_url', true, $url, $parsed_url );

	}



	/**

	 * Checks if the file exists before it passes the file to photon

	 *

	 * @param string $src The image URL

	 * @return string

	 **/

	protected static function strip_image_dimensions_maybe( $src ){

		$stripped_src = $src;



		// Build URL, first removing WP's resized string so we pass the original image to Photon

		if ( preg_match( '#(-\d+x\d+)\.(' . implode('|', self::$extensions ) . '){1}$#i', $src, $src_parts ) ) {

			$stripped_src = str_replace( $src_parts[1], '', $src );

			$upload_dir = wp_upload_dir();



			// Extracts the file path to the image minus the base url

			$file_path = substr( $stripped_src, strlen ( $upload_dir['baseurl'] ) );



			if( file_exists( $upload_dir["basedir"] . $file_path ) )

				$src = $stripped_src;

		}



		return $src;

	}



	/**

	 * Provide an array of available image sizes and corresponding dimensions.

	 * Similar to get_intermediate_image_sizes() except that it includes image sizes' dimensions, not just their names.

	 *

	 * @global $wp_additional_image_sizes

	 * @uses get_option

	 * @return array

	 */

	protected static function image_sizes() {

		if ( null == self::$image_sizes ) {

			global $_wp_additional_image_sizes;



			// Populate an array matching the data structure of $_wp_additional_image_sizes so we have a consistent structure for image sizes

			$images = array(

				'thumb'  => array(

					'width'  => intval( get_option( 'thumbnail_size_w' ) ),

					'height' => intval( get_option( 'thumbnail_size_h' ) ),

					'crop'   => (bool) get_option( 'thumbnail_crop' )

				),

				'medium' => array(

					'width'  => intval( get_option( 'medium_size_w' ) ),

					'height' => intval( get_option( 'medium_size_h' ) ),

					'crop'   => false

				),

				'large'  => array(

					'width'  => intval( get_option( 'large_size_w' ) ),

					'height' => intval( get_option( 'large_size_h' ) ),

					'crop'   => false

				),

				'full'   => array(

					'width'  => null,

					'height' => null,

					'crop'   => false

				)

			);



			// Compatibility mapping as found in wp-includes/media.php

			$images['thumbnail'] = $images['thumb'];



			// Update class variable, merging in $_wp_additional_image_sizes if any are set

			if ( is_array( $_wp_additional_image_sizes ) && ! empty( $_wp_additional_image_sizes ) )

				self::$image_sizes = array_merge( $images, $_wp_additional_image_sizes );

			else

				self::$image_sizes = $images;

		}



		return is_array( self::$image_sizes ) ? self::$image_sizes : array();

	}



	/**

	 * Pass og:image URLs through Photon

	 *

	 * @param array $tags

	 * @param array $parameters

	 * @uses jetpack_photon_url

	 * @return array

	 */

	function filter_open_graph_tags( $tags, $parameters ) {

		if ( empty( $tags['og:image'] ) ) {

			return $tags;

		}



		$photon_args = array(

			'fit' => sprintf( '%d,%d', 2 * $parameters['image_width'], 2 * $parameters['image_height'] ),

		);



		if ( is_array( $tags['og:image'] ) ) {

			$images = array();

			foreach ( $tags['og:image'] as $image ) {

				$images[] = jetpack_photon_url( $image, $photon_args );

			}

			$tags['og:image'] = $images;

		} else {

			$tags['og:image'] = jetpack_photon_url( $tags['og:image'], $photon_args );

		}



		return $tags;

	}



	/**

	 * Enqueue Photon helper script

	 *

	 * @uses wp_enqueue_script, plugins_url

	 * @action wp_enqueue_script

	 * @return null

	 */

	public function action_wp_enqueue_scripts() {

		wp_enqueue_script( 'jetpack-photon', plugins_url( 'modules/photon/photon.js', JETPACK__PLUGIN_FILE ), array( 'jquery' ), 20130122, true );

	}

}