<?php

/**

 * WordPress API for creating bbcode-like tags or what WordPress calls

 * "shortcodes". The tag and attribute parsing or regular expression code is

 * based on the Textpattern tag parser.

 *

 * A few examples are below:

 *

 * [shortcode /]

 * [shortcode foo="bar" baz="bing" /]

 * [shortcode foo="bar"]content[/shortcode]

 *

 * Shortcode tags support attributes and enclosed content, but does not entirely

 * support inline shortcodes in other shortcodes. You will have to call the

 * shortcode parser in your function to account for that.

 *

 * {@internal

 * Please be aware that the above note was made during the beta of WordPress 2.6

 * and in the future may not be accurate. Please update the note when it is no

 * longer the case.}}

 *

 * To apply shortcode tags to content:

 *

 *     $out = do_shortcode( $content );

 *

 *

 * @package WordPress

 * @subpackage Shortcodes

 * @since 2.5.0

 */

/**

 * Container for storing shortcode tags and their hook to call for the shortcode

 *

 * @since 2.5.0

 *

 * @name $shortcode_tags

 * @var array

 * @global array $shortcode_tags

 */

$shortcode_tags = array();

/**

 * Adds a new shortcode.

 *

 * Care should be taken through prefixing or other means to ensure that the

 * shortcode tag being added is unique and will not conflict with other,

 * already-added shortcode tags. In the event of a duplicated tag, the tag

 * loaded last will take precedence.

 *

 * @since 2.5.0

 *

 * @global array $shortcode_tags

 *

 * @param string   $tag      Shortcode tag to be searched in post content.

 * @param callable $callback The callback function to run when the shortcode is found.

 *                           Every shortcode callback is passed three parameters by default,

 *                           including an array of attributes (`$atts`), the shortcode content

 *                           or null if not set (`$content`), and finally the shortcode tag

 *                           itself (`$shortcode_tag`), in that order.

 */

function add_shortcode( $tag, $callback ) {

	global $shortcode_tags;

		$message = __( 'Invalid shortcode name: Empty name given.' );

		_doing_it_wrong( __FUNCTION__, $message, '4.4.0' );

		return;

	}

	if ( 0 !== preg_match( '@[<>&/\[\]\x00-\x20=]@', $tag ) ) {

		$message = sprintf( __( 'Invalid shortcode name: %1$s. Do not use spaces or reserved characters: %2$s' ), $tag, '& / < > [ ] =' );

		_doing_it_wrong( __FUNCTION__, $message, '4.4.0' );

		return;

	}

	$shortcode_tags[ $tag ] = $callback;

}

/**

 * Removes hook for shortcode.

 *

 * @since 2.5.0

 *

 * @global array $shortcode_tags

 *

 * @param string $tag Shortcode tag to remove hook for.

 */

function remove_shortcode( $tag ) {

	global $shortcode_tags;

	unset( $shortcode_tags[ $tag ] );

}

/**

 * Clear all shortcodes.

 *

 * This function is simple, it clears all of the shortcode tags by replacing the

 * shortcodes global by a empty array. This is actually a very efficient method

 * for removing all shortcodes.

 *

 * @since 2.5.0

 *

 * @global array $shortcode_tags

 */

function remove_all_shortcodes() {

	global $shortcode_tags;

	$shortcode_tags = array();

}

/**

 * Whether a registered shortcode exists named $tag

 *

 * @since 3.6.0

 *

 * @global array $shortcode_tags List of shortcode tags and their callback hooks.

 *

 * @param string $tag Shortcode tag to check.

 * @return bool Whether the given shortcode exists.

 */

function shortcode_exists( $tag ) {

	global $shortcode_tags;

	return array_key_exists( $tag, $shortcode_tags );

}

/**

 * Whether the passed content contains the specified shortcode

 *

 * @since 3.6.0

 *

 * @global array $shortcode_tags

 *

 * @param string $content Content to search for shortcodes.

 * @param string $tag     Shortcode tag to check.

 * @return bool Whether the passed content contains the given shortcode.

 */

function has_shortcode( $content, $tag ) {

	if ( false === strpos( $content, '[' ) ) {

		return false;

	}

	if ( shortcode_exists( $tag ) ) {

		preg_match_all( '/' . get_shortcode_regex() . '/', $content, $matches, PREG_SET_ORDER );

		if ( empty( $matches ) ) {

			return false;

		}

		foreach ( $matches as $shortcode ) {

			if ( $tag === $shortcode[2] ) {

				return true;

			} elseif ( ! empty( $shortcode[5] ) && has_shortcode( $shortcode[5], $tag ) ) {

				return true;

			}

		}

	}

	return false;

}

/**

 * Search content for shortcodes and filter shortcodes through their hooks.

 *

 * If there are no shortcode tags defined, then the content will be returned

 * without any filtering. This might cause issues when plugins are disabled but

 * the shortcode will still show up in the post or content.

 *

 * @since 2.5.0

 *

 * @global array $shortcode_tags List of shortcode tags and their callback hooks.

 *

 * @return string Content with shortcodes filtered out.

 */

function do_shortcode( $content, $ignore_html = false ) {

	global $shortcode_tags;

	if ( false === strpos( $content, '[' ) ) {

		return $content;

	}

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

		return $content;

	}

	// Find all registered tag names in $content.

	preg_match_all( '@\[([^<>&/\[\]\x00-\x20=]++)@', $content, $matches );

	$tagnames = array_intersect( array_keys( $shortcode_tags ), $matches[1] );

	if ( empty( $tagnames ) ) {

		return $content;

	}

	$content = do_shortcodes_in_html_tags( $content, $ignore_html, $tagnames );

	$pattern = get_shortcode_regex( $tagnames );

	$content = preg_replace_callback( "/$pattern/", 'do_shortcode_tag', $content );

	$content = unescape_invalid_shortcodes( $content );

	return $content;

}

/**

 * Retrieve the shortcode regular expression for searching.

 *

 * The regular expression combines the shortcode tags in the regular expression

 * in a regex class.

 *

 * The regular expression contains 6 different sub matches to help with parsing.

 *

 * 1 - An extra [ to allow for escaping shortcodes with double [[]]

 * 2 - The shortcode name

 * 3 - The shortcode argument list

 * 4 - The self closing /

 * 5 - The content of a shortcode when it wraps some content.

 * 6 - An extra ] to allow for escaping shortcodes with double [[]]

 *

 * @since 2.5.0

 * @since 4.4.0 Added the `$tagnames` parameter.

 *

 * @global array $shortcode_tags

 *

 * @param array $tagnames Optional. List of shortcodes to find. Defaults to all registered shortcodes.

 * @return string The shortcode search regular expression

 */

function get_shortcode_regex( $tagnames = null ) {

	global $shortcode_tags;

	if ( empty( $tagnames ) ) {

		$tagnames = array_keys( $shortcode_tags );

	}

	$tagregexp = join( '|', array_map( 'preg_quote', $tagnames ) );

	// Also, see shortcode_unautop() and shortcode.js.

	// phpcs:disable Squiz.Strings.ConcatenationSpacing.PaddingFound -- don't remove regex indentation

		.     '(?:'

		.     ')*?'

		. ')'

		. '(?:'

		. '|'

		.     '(?:'

		.             '(?:'

		.             ')*+'

		.         ')'

		.     ')?'

		. ')'

	// phpcs:enable

}

/**

 * Regular Expression callable for do_shortcode() for calling shortcode hook.

 *

 * @see get_shortcode_regex for details of the match array contents.

 *

 * @since 2.5.0

 * @access private

 *

 * @global array $shortcode_tags

 *

 * @param array $m Regular expression match array

 * @return string|false False on failure.

 */

function do_shortcode_tag( $m ) {

	global $shortcode_tags;

		return substr( $m[0], 1, -1 );

	}

	$tag  = $m[2];

	$attr = shortcode_parse_atts( $m[3] );

	if ( ! is_callable( $shortcode_tags[ $tag ] ) ) {

		$message = sprintf( __( 'Attempting to parse a shortcode without a valid callback: %s' ), $tag );

		_doing_it_wrong( __FUNCTION__, $message, '4.3.0' );

		return $m[0];

	}

	/**

	 * Filters whether to call a shortcode callback.

	 *

	 * shortcode generation process, returning that value instead.

	 *

	 * @since 4.7.0

	 *

	 * @param string       $tag         Shortcode name.

	 * @param array|string $attr        Shortcode attributes array or empty string.

	 * @param array        $m           Regular expression match array.

	 */

	$return = apply_filters( 'pre_do_shortcode_tag', false, $tag, $attr, $m );

	if ( false !== $return ) {

		return $return;

	}

	$content = isset( $m[5] ) ? $m[5] : null;

	$output = $m[1] . call_user_func( $shortcode_tags[ $tag ], $attr, $content, $tag ) . $m[6];

	/**

	 * Filters the output created by a shortcode callback.

	 *

	 * @since 4.7.0

	 *

	 * @param string       $output Shortcode output.

	 * @param string       $tag    Shortcode name.

	 * @param array|string $attr   Shortcode attributes array or empty string.

	 * @param array        $m      Regular expression match array.

	 */

	return apply_filters( 'do_shortcode_tag', $output, $tag, $attr, $m );

}

/**

 * Search only inside HTML elements for shortcodes and process them.

 *

 * Any [ or ] characters remaining inside elements will be HTML encoded

 * to prevent interference with shortcodes that are outside the elements.

 * Assumes $content processed by KSES already.  Users with unfiltered_html

 * capability may get unexpected output if angle braces are nested in tags.

 *

 * @since 4.2.3

 *

 * @return string Content with shortcodes filtered out.

 */

function do_shortcodes_in_html_tags( $content, $ignore_html, $tagnames ) {

	// Normalize entities in unfiltered HTML before adding placeholders.

	$trans   = array(

		'[' => '[',

		']' => ']',

	);

	$content = strtr( $content, $trans );

	$trans   = array(

		'[' => '[',

		']' => ']',

	);

	$pattern = get_shortcode_regex( $tagnames );

	$textarr = wp_html_split( $content );

	foreach ( $textarr as &$element ) {

			continue;

		}

		$noopen  = false === strpos( $element, '[' );

		$noclose = false === strpos( $element, ']' );

		if ( $noopen || $noclose ) {

			// This element does not contain shortcodes.

			if ( $noopen xor $noclose ) {

				$element = strtr( $element, $trans );

			}

			continue;

		}

		if ( $ignore_html || '<!--' === substr( $element, 0, 4 ) || '<![CDATA[' === substr( $element, 0, 9 ) ) {

			$element = strtr( $element, $trans );

			continue;

		}

		$attributes = wp_kses_attr_parse( $element );

		if ( false === $attributes ) {

			// Some plugins are doing things like [name] <[email]>.

			if ( 1 === preg_match( '%^<\s*\[\[?[^\[\]]+\]%', $element ) ) {

				$element = preg_replace_callback( "/$pattern/", 'do_shortcode_tag', $element );

			}

			$element = strtr( $element, $trans );

			continue;

		}

		$front   = array_shift( $attributes );

		$back    = array_pop( $attributes );

		$matches = array();

		preg_match( '%[a-zA-Z0-9]+%', $front, $matches );