slideshow.php

<?php //phpcs:ignore WordPress.Files.FileName.InvalidClassFileName

use Automattic\Jetpack\Assets;

/**
 * Slideshow shortcode.
 * Adds a new "slideshow" gallery type when adding a gallery using the classic editor.
 *
 * @package Jetpack
 */

/**
 * Slideshow shortcode usage: [gallery type="slideshow"] or the older [slideshow]
 */
class Jetpack_Slideshow_Shortcode {
	/**
	 * Number of slideshows on a page.
	 *
	 * @var int
	 */
	public $instance_count = 0;

	/**
	 * Constructor
	 */
	public function __construct() {
		global $shortcode_tags;

		// Only if the slideshow shortcode has not already been defined.
		if ( ! array_key_exists( 'slideshow', $shortcode_tags ) ) {
			add_shortcode( 'slideshow', array( $this, 'shortcode_callback' ) );
		}

		// Only if the gallery shortcode has not been redefined.
		if ( isset( $shortcode_tags['gallery'] ) && 'gallery_shortcode' === $shortcode_tags['gallery'] ) {
			add_filter( 'post_gallery', array( $this, 'post_gallery' ), 1002, 2 );
			add_filter( 'jetpack_gallery_types', array( $this, 'add_gallery_type' ), 10 );
		}
	}

	/**
	 * Responds to the [gallery] shortcode, but not an actual shortcode callback.
	 *
	 * @param string $value An empty string if nothing has modified the gallery output, the output html otherwise.
	 * @param array  $attr  The shortcode attributes array.
	 *
	 * @return string The (un)modified $value
	 */
	public function post_gallery( $value, $attr ) {
		// Bail if somebody else has done something.
		if ( ! empty( $value ) ) {
			return $value;
		}

		// If [gallery type="slideshow"] have it behave just like [slideshow].
		if ( ! empty( $attr['type'] ) && 'slideshow' === $attr['type'] ) {
			return $this->shortcode_callback( $attr );
		}

		return $value;
	}

	/**
	 * Add the Slideshow type to gallery settings
	 *
	 * @see Jetpack_Tiled_Gallery::media_ui_print_templates
	 *
	 * @param array $types An array of types where the key is the value, and the value is the caption.
	 *
	 * @return array
	 */
	public function add_gallery_type( $types = array() ) {
		$types['slideshow'] = esc_html__( 'Slideshow', 'jetpack' );

		return $types;
	}

	/**
	 * Display shortcode.
	 *
	 * @param array $attr Shortcode attributes.
	 */
	public function shortcode_callback( $attr ) {
		$post_id = get_the_ID();

		$attr = shortcode_atts(
			array(
				'trans'     => 'fade',
				'order'     => 'ASC',
				'orderby'   => 'menu_order ID',
				'id'        => $post_id,
				'include'   => '',
				'exclude'   => '',
				'autostart' => true,
				'size'      => '',
			),
			$attr,
			'slideshow'
		);

		if ( 'rand' === strtolower( $attr['order'] ) ) {
			$attr['orderby'] = 'none';
		}

		$attr['orderby'] = sanitize_sql_orderby( $attr['orderby'] );
		if ( ! $attr['orderby'] ) {
			$attr['orderby'] = 'menu_order ID';
		}

		if ( ! $attr['size'] ) {
			$attr['size'] = 'full';
		}

		// Don't restrict to the current post if include.
		$post_parent = ( empty( $attr['include'] ) ) ? intval( $attr['id'] ) : null;

		$attachments = get_posts(
			array(
				'post_status'      => 'inherit',
				'post_type'        => 'attachment',
				'post_mime_type'   => 'image',
				'posts_per_page'   => - 1,
				'post_parent'      => $post_parent,
				'order'            => $attr['order'],
				'orderby'          => $attr['orderby'],
				'include'          => $attr['include'],
				'exclude'          => $attr['exclude'],
				'suppress_filters' => false,
			)
		);

		if ( count( $attachments ) < 1 ) {
			return false;
		}

		$gallery_instance = sprintf( 'gallery-%d-%d', $attr['id'], ++$this->instance_count );

		$gallery = array();
		foreach ( $attachments as $attachment ) {
			$attachment_image_src   = wp_get_attachment_image_src( $attachment->ID, $attr['size'] );
			$attachment_image_src   = $attachment_image_src[0]; // [url, width, height].
			$attachment_image_title = get_the_title( $attachment->ID );
			$attachment_image_alt   = get_post_meta( $attachment->ID, '_wp_attachment_image_alt', true );
			/**
			 * Filters the Slideshow slide caption.
			 *
			 * @module shortcodes
			 *
			 * @since 2.3.0
			 *
			 * @param string wptexturize( strip_tags( $attachment->post_excerpt ) ) Post excerpt.
			 * @param string $attachment ->ID Attachment ID.
			 */
			$caption = apply_filters( 'jetpack_slideshow_slide_caption', wptexturize( wp_strip_all_tags( $attachment->post_excerpt ) ), $attachment->ID );

			$gallery[] = (object) array(
				'src'      => (string) esc_url_raw( $attachment_image_src ),
				'id'       => (string) $attachment->ID,
				'title'    => (string) esc_attr( $attachment_image_title ),
				'alt'      => (string) esc_attr( $attachment_image_alt ),
				'caption'  => (string) $caption,
				'itemprop' => 'image',
			);
		}

		$color = Jetpack_Options::get_option( 'slideshow_background_color', 'black' );

		$js_attr = array(
			'gallery'   => $gallery,
			'selector'  => $gallery_instance,
			'trans'     => $attr['trans'] ? $attr['trans'] : 'fade',
			'autostart' => $attr['autostart'] ? $attr['autostart'] : 'true',
			'color'     => $color,
		);

		// Show a link to the gallery in feeds.
		if ( is_feed() ) {
			return sprintf(
				'<a href="%s">%s</a>',
				esc_url( get_permalink( $post_id ) . '#' . $gallery_instance . '-slideshow' ),
				esc_html__( 'Click to view slideshow.', 'jetpack' )
			);
		}

		return $this->slideshow_js( $js_attr );
	}

	/**
	 * Render the slideshow js
	 *
	 * Returns the necessary markup and js to fire a slideshow.
	 *
	 * @param array $attr Attributes for the slideshow.
	 *
	 * @uses $this->enqueue_scripts()
	 *
	 * @return string HTML output.
	 */
	public function slideshow_js( $attr ) {
		// Enqueue scripts.
		$this->enqueue_scripts();

		$output = '';

		if ( defined( 'JSON_HEX_AMP' ) ) {
			// This is nice to have, but not strictly necessary since we use _wp_specialchars() below.
			$gallery = wp_json_encode( $attr['gallery'], JSON_HEX_TAG | JSON_HEX_AMP | JSON_HEX_APOS | JSON_HEX_QUOT ); // phpcs:ignore PHPCompatibility
		} else {
			$gallery = wp_json_encode( $attr['gallery'] );
		}

		$output .= '<p class="jetpack-slideshow-noscript robots-nocontent">' . esc_html__( 'This slideshow requires JavaScript.', 'jetpack' ) . '</p>';

		/*
		 * The input to json_encode() above can contain '&quot;'.
		 *
		 * For calls to json_encode() lacking the JSON_HEX_AMP option,
		 * that '&quot;' is left unaltered.  Running '&quot;' through esc_attr()
		 * also leaves it unaltered since esc_attr() does not double-encode.
		 *
		 * This means we end up with an attribute like
		 * `data-gallery="{&quot;foo&quot;:&quot;&quot;&quot;}"`,
		 * which is interpreted by the browser as `{"foo":"""}`,
		 * which cannot be JSON decoded.
		 *
		 * The preferred workaround is to include the JSON_HEX_AMP (and friends)
		 * options, but these are not available until 5.3.0.
		 * Alternatively, we can use _wp_specialchars( , , , true ) instead of
		 * esc_attr(), which will double-encode.
		 *
		 * Since we can't rely on JSON_HEX_AMP, we do both.
		 *
		 * @todo Update when minimum is PHP 5.3+
		 */
		$gallery_attributes = _wp_specialchars( wp_check_invalid_utf8( $gallery ), ENT_QUOTES, false, true );

		$output .= sprintf(
			'<div id="%s" class="slideshow-window jetpack-slideshow slideshow-%s" data-trans="%s" data-autostart="%s" data-gallery="%s" itemscope itemtype="https://schema.org/ImageGallery"></div>',
			esc_attr( $attr['selector'] . '-slideshow' ),
			esc_attr( $attr['color'] ),
			esc_attr( $attr['trans'] ),
			esc_attr( $attr['autostart'] ),
			$gallery_attributes
		);

		return $output;
	}

	/**
	 * Actually enqueues the scripts and styles.
	 */
	public function enqueue_scripts() {

		wp_enqueue_script( 'jquery-cycle', plugins_url( '/js/jquery.cycle.min.js', __FILE__ ), array( 'jquery' ), '20161231', true );
		wp_enqueue_script(
			'jetpack-slideshow',
			Assets::get_file_url_for_environment( '_inc/build/shortcodes/js/slideshow-shortcode.min.js', 'modules/shortcodes/js/slideshow-shortcode.js' ),
			array( 'jquery-cycle' ),
			'20160119.1',
			true
		);
		wp_enqueue_style(
			'jetpack-slideshow',
			plugins_url( '/css/slideshow-shortcode.css', __FILE__ ),
			array(),
			JETPACK__VERSION
		);
		wp_style_add_data( 'jetpack-slideshow', 'rtl', 'replace' );

		wp_localize_script(
			'jetpack-slideshow',
			'jetpackSlideshowSettings',
			/**
			 * Filters the slideshow JavaScript spinner.
			 *
			 * @module shortcodes
			 *
			 * @since 2.1.0
			 * @since 4.7.0 Added the `speed` option to the array of options.
			 *
			 * @param array $args
			 * - string - spinner - URL of the spinner image.
			 * - string - speed   - Speed of the slideshow. Defaults to 4000.
			 */
			apply_filters(
				'jetpack_js_slideshow_settings',
				array(
					'spinner' => plugins_url( '/img/slideshow-loader.gif', __FILE__ ),
					'speed'   => '4000',
				)
			)
		);
	}

	/**
	 * Instantiate shortcode.
	 */
	public static function init() {
		new Jetpack_Slideshow_Shortcode();
	}
}

Jetpack_Slideshow_Shortcode::init();