<?php
/**
 * PHPTAL templating engine
 *
 * PHP Version 5
 *
 * @category HTML
 * @package  PHPTAL
 * @author   Laurent Bedubourg <lbedubourg@motion-twin.com>
 * @author   Kornel Lesiński <kornel@aardvarkmedia.co.uk>
 * @license  http://www.gnu.org/licenses/lgpl.html GNU Lesser General Public License
 * @version  SVN: $Id: XmlnsState.php 605 2009-05-03 02:50:26Z kornel $
 * @link     http://phptal.org/
 */
/**
 * Stores XMLNS aliases fluctuation in the xml flow.
 *
 * This class is used to bind a PHPTAL namespace to an alias, for example using
 * xmlns:t="http://xml.zope.org/namespaces/tal" and later use t:repeat instead
 * of tal:repeat.
 *
 * @package PHPTAL
 * @subpackage Dom
 * @author Laurent Bedubourg <lbedubourg@motion-twin.com>
 */
class PHPTAL_Dom_XmlnsState
{
    /** Create a new XMLNS state inheriting provided aliases. */
    public function __construct(array $prefix_to_uri, $current_default)
    {
        $this->prefix_to_uri = $prefix_to_uri;
        $this->current_default = $current_default;
    }

    public function prefixToNamespaceURI($prefix)
    {
        if ($prefix === 'xmlns') return 'http://www.w3.org/2000/xmlns/';
        if ($prefix === 'xml') return 'http://www.w3.org/XML/1998/namespace';

        // domdefs provides fallback for all known phptal ns
        if (isset($this->prefix_to_uri[$prefix])) {
            return $this->prefix_to_uri[$prefix];
        } else {
            return PHPTAL_Dom_Defs::getInstance()->prefixToNamespaceURI($prefix);
        }
    }

    /** Returns true if $attName is a valid attribute name, false otherwise. */
    public function isValidAttributeNS($namespace_uri, $local_name)
    {
        return PHPTAL_Dom_Defs::getInstance()->isValidAttributeNS($namespace_uri, $local_name);
    }

    public function isHandledNamespace($namespace_uri)
    {
        return PHPTAL_Dom_Defs::getInstance()->isHandledNamespace($namespace_uri);
    }

    /**
     * Returns a new XmlnsState inheriting of $this if $nodeAttributes contains
     * xmlns attributes, returns $this otherwise.
     *
     * This method is used by the PHPTAL parser to keep track of xmlns fluctuation for
     * each encountered node.
     */
    public function newElement(array $nodeAttributes)
    {
        $prefix_to_uri = $this->prefix_to_uri;
        $current_default = $this->current_default;

        $changed = false;
        foreach ($nodeAttributes as $qname => $value) {
            if (preg_match('/^xmlns:(.+)$/', $qname, $m)) {
                $changed = true;
                list(,$prefix) = $m;
                $prefix_to_uri[$prefix] = $value;
            }

            if ($qname == 'xmlns') {$changed=true;$current_default = $value;}
        }

        if ($changed) {
            return new PHPTAL_Dom_XmlnsState($prefix_to_uri, $current_default);
        } else {
            return $this;
        }
    }

    function getCurrentDefaultNamespaceURI()
    {
        return $this->current_default;
    }

    private $prefix_to_uri, $current_default;
}
