root/trunk/wp-includes/class.wp-dependencies.php

<?php
/**
 * BackPress Scripts enqueue.
 *
 * These classes were refactored from the WordPress WP_Scripts and WordPress
 * script enqueue API.
 *
 * @package BackPress
 * @since r74
 */

/**
 * BackPress enqueued dependiences class.
 *
 * @package BackPress
 * @uses _WP_Dependency
 * @since r74
 */
class WP_Dependencies {
    var $registered = array();
    var $queue = array();
    var $to_do = array();
    var $done = array();
    var $args = array();

    function WP_Dependencies() {
        $args = func_get_args();
        call_user_func_array( array(&$this, '__construct'), $args );
    }

    function __construct() {}

    /**
     * Do the dependencies
     *
     * Process the items passed to it or the queue.  Processes all dependencies.
     *
     * @param mixed handles (optional) items to be processed.  (void) processes queue, (string) process that item, (array of strings) process those items
     * @return array Items that have been processed
     */
    function do_items( $handles = false ) {
        // Print the queue if nothing is passed.  If a string is passed, print that script.  If an array is passed, print those scripts.
        $handles = false === $handles ? $this->queue : (array) $handles;
        $this->all_deps( $handles );

        foreach( $this->to_do as $handle ) {
            if ( !in_array($handle, $this->done) && isset($this->registered[$handle]) ) {
                if ( $this->registered[$handle]->src ) { // Else it defines a group.
                    $this->do_item( $handle );
                }
                $this->done[] = $handle;
            }
        }

        $this->to_do = array();
        return $this->done;
    }

    function do_item( $handle ) {
        return isset($this->registered[$handle]);
    }

    /**
     * Determines dependencies
     *
     * Recursively builds array of items to process taking dependencies into account.  Does NOT catch infinite loops.
     *

     * @param mixed handles Accepts (string) dep name or (array of strings) dep names
     * @param bool recursion Used internally when function calls itself
     */
    function all_deps( $handles, $recursion = false ) {
        if ( !$handles = (array) $handles )
            return false;

        foreach ( $handles as $handle ) {
            $handle = explode('?', $handle);
            if ( isset($handle[1]) )
                $this->args[$handle[0]] = $handle[1];
            $handle = $handle[0];

            if ( isset($this->to_do[$handle]) ) // Already grobbed it and its deps
                continue;

            $keep_going = true;
            if ( !isset($this->registered[$handle]) )
                $keep_going = false; // Script doesn't exist
            elseif ( $this->registered[$handle]->deps && array_diff($this->registered[$handle]->deps, array_keys($this->registered)) )
                $keep_going = false; // Script requires deps which don't exist (not a necessary check.  efficiency?)
            elseif ( $this->registered[$handle]->deps && !$this->all_deps( $this->registered[$handle]->deps, true ) )
                $keep_going = false; // Script requires deps which don't exist

            if ( !$keep_going ) { // Either script or its deps don't exist.
                if ( $recursion )
                    return false; // Abort this branch.
                else
                    continue; // We're at the top level.  Move on to the next one.
            }

            $this->to_do[$handle] = true;
        }

        if ( !$recursion ) // at the end
            $this->to_do = array_keys( $this->to_do );
        return true;
    }

    /**
     * Adds item
     *
     * Adds the item only if no item of that name already exists
     *
     * @param string handle Script name
     * @param string src Script url
     * @param array deps (optional) Array of script names on which this script depends
     * @param string ver (optional) Script version (used for cache busting)
     * @return array Hierarchical array of dependencies
     */
    function add( $handle, $src, $deps = array(), $ver = false, $args = null ) {
        if ( isset($this->registered[$handle]) )
            return false;
        $this->registered[$handle] = new _WP_Dependency( $handle, $src, $deps, $ver, $args );
        return true;
    }

    /**
     * Adds extra data
     *
     * Adds data only if script has already been added
     *
     * @param string handle Script name
     * @param string data_name Name of object in which to store extra data
     * @param array data Array of extra data
     * @return bool success
     */
    function add_data( $handle, $data_name, $data ) {
        if ( !isset($this->registered[$handle]) )
            return false;
        return $this->registered[$handle]->add_data( $data_name, $data );
    }

    function remove( $handles ) {
        foreach ( (array) $handles as $handle )
            unset($this->registered[$handle]);
    }

    function enqueue( $handles ) {
        foreach ( (array) $handles as $handle ) {
            $handle = explode('?', $handle);
            if ( !in_array($handle[0], $this->queue) && isset($this->registered[$handle[0]]) ) {
                $this->queue[] = $handle[0];
                if ( isset($handle[1]) )
                    $this->args[$handle[0]] = $handle[1];
            }
        }
    }

    function dequeue( $handles ) {
        foreach ( (array) $handles as $handle )
            unset( $this->queue[$handle] );
    }

    function query( $handle, $list = 'registered' ) { // registered, queue, done, to_do
        switch ( $list ) :
        case 'registered':
        case 'scripts': // back compat
            if ( isset($this->registered[$handle]) )
                return $this->registered[$handle];
            break;
        case 'to_print': // back compat
        case 'printed': // back compat
            if ( 'to_print' == $list )
                $list = 'to_do';
            else
                $list = 'printed';
        default:
            if ( in_array($handle, $this->$list) )
                return true;
            break;
        endswitch;
        return false;
    }

}

class _WP_Dependency {
    var $handle;
    var $src;
    var $deps = array();
    var $ver = false;
    var $args = null;

    var $extra = array();

    function _WP_Dependency() {
        @list($this->handle, $this->src, $this->deps, $this->ver, $this->args) = func_get_args();
        if ( !is_array($this->deps) )
            $this->deps = array();
        if ( !$this->ver )
            $this->ver = false;
    }

    function add_data( $name, $data ) {
        if ( !is_scalar($name) )
            return false;
        $this->extra[$name] = $data;
        return true;
    }
}