<?php
/**
 * Markup Handler: XML2Html
 *
 * $Id$
 *
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @license PHP License
 * @package wb
 * @subpackage Markup
 */

WBClass::load('WBString'
    , 'WBMarkup_Handler_Xml2Wxml');

/**
 * Markup Scanner Handler: XML2HTML
 *
 * Convert Wombat XML data to HTML
 *
 * @version 0.5.0
 * @package wb
 * @subpackage Markup
 */
class WBMarkup_Handler_Xml2Html extends WBMarkup_Handler_Xml2Wxml
{
    /**
     * actual wxml config
     * @var WBConfig
     */
    private $config;

    /**
     * List of WBMarkup_Listener
     * @var array
     */
    private $listener = array();

    /**
     * template engine
     * @var patTemplate
     */
    private $tmpl;

    /**
     * template dir
     * @var string
     */
    private $tmplDir    =   '';

    /**
     * constructor
     *
     * Load config
     */
    public function __construct()
    {
        $this->config   =   WBClass::create('WBConfig');
        $this->config->load('wxml/config');
        $this->initTmplEngine();
    }

    /**
     * override default template dir
     *
     * @param string $dir
     */
    public function setTmplDir($dir)
    {
        if (empty($dir)) {
            return;
        }
        $this->tmplDir  =   $dir;
        $this->initTmplEngine($dir);
    }

    /**
     * Initialize Template Engine
     *
     * Load default convert if available
     * @param string $dir
     */
    private function initTmplEngine($dir = '')
    {
        if (empty($dir)) {
            $dir    =   '__default';
        }

        $base   =   WBParam::get('wb/dir/base');
        $tmpl   =   'Wxml/converter/' . trim($dir, '/') . $this->getPatTemplateSuffix();;
        if (!file_exists( $base . '/template/'  . $tmpl)) {
            return;
        }
        if (!$this->tmpl) {
            $this->tmpl     =   $this->createPatTemplate();
        }
        $this->tmpl->readTemplatesFromInput($tmpl);
    }

    /**
     * Get patTemplate object
     * 
     * @return patTemplate
     */
    protected function createPatTemplate()
    {
        return WBClass::create('patTemplate');
    }

    /**
     * Get File Name Suffix
     *
     * @return string
     */
    protected function getPatTemplateSuffix()
    {
        return '.tmpl';
    }

   /**
    * handler on start beginning of scan
    *
    *
    *
    * @param string $content
    * @return bool usually true, false to stop the scanner
    */
    public function onScanStart(&$content)
    {
        if (!parent::onScanStart($content)) {
            return false;
        }

        foreach ($this->listener as $l) {
            $l->onScanStart($content);
        }

        return true;
    }

    /**
     * add tag listener
     *
     * @param WBMarkup_Listener $l
     */
    public function addListener($l)
    {
        $l->onScanStart($this->content);
        $this->listener[]   =   $l;
    }

   /**
    * handler on start element
    *
    * @param string $ns The used namespace, if set. otherwise null
    * @param string $tag the tag itself
    * @param array  $attributes the attributes of the found element
    * @param bool $isEmpty true if it is a start- and closing-Element (e.g. <br />)
    * @return bool usually true, false to stop the scanner
    */
    public function onStartElement($ns, $tag, $attributes, $isEmpty)
    {
        if (!parent::onStartElement($ns, $tag, $attributes, $isEmpty)) {
            return false;
        }

        foreach ($this->listener as $l) {
            $l->onStartElement($this->doc[$this->depth]);
        }

        return true;
    }

   /**
    * handler fo cData
    *
    * Simply add cDate to document
    *
    * Copied regular expression to find and replace URL from
    * {@link http://snipplr.com/view/6889/regular-expressions-for-uri-validationparsing/}
    * and removed parentheses
    *
    * @uses replaceUrlString()
    * @param string $cData character data
    * @return bool usually true, false to stop the scanner
    */
    public function onCharacterData($cData)
    {
        // find and replace URL strings
        if (strstr($cData, '://')) {

            $regex  =   '/(https?|ftp):\\/\\/((?:[a-z0-9@:.-]|%[0-9A-F]{2}){3,})(?::(\\d+))?((?:\\/(?:[a-z0-9-._~!$&\'*+,;=:@]|%[0-9A-F]{2})*)*)(?:\\?((?:[a-z0-9-._~!$&\'*+,;=:\\/?@]|%[0-9A-F]{2})*))?(?:#((?:[a-z0-9-._~!$&\'*+,;=:\\/?@]|%[0-9A-F]{2})*))?/i';
            $cData =   preg_replace_callback($regex
                                , array($this, 'replaceUrlString')
                                , $cData);
        }

        return parent::onCharacterData($cData);
    }

   /**
    * test handler on end element
    *
    * @param string $ns The used namespace, if set. otherwise null
    * @param string $tag the tag itself
    * @param bool $empty defines if the tag is empty
    * @return bool usually true, false to stop the scanner
    */
    public function onEndElement($ns, $tag, $empty)
    {
        // serialize node
        if( !$this->depth ) {
            return true;
        }
        $node   =   array_pop($this->doc);

        // inform listener
        foreach ($this->listener as $l) {
            $l->onEndElement($node);
        }

        if ($node['ns']) {
            $this->convert($node['ns'], $node['tag'], $node);
        } else {
            $this->convertDefault($node['tag'], $node);
        }

        --$this->depth;
        if( $this->depth < 0 ) {
            $this->depth    =   0;
        }

        $this->doc[$this->depth]['cData'][]    =   $this->node2String($node);
        return true;
    }

   /**
    * called right after scan is complete
    *
    * @return bool usually true, false to stop the scanner
    */
    public function onScanComplete()
    {
        $this->content  =   $this->node2String($this->doc[0]);

        // inform listener
        foreach ($this->listener as $l) {
            $l->onScanComplete($this->content);
        }

        // inform converter
        foreach (array_keys($this->con) as $con) {
            $this->con[$con]->reset();
        }

        // flush listener
        $this->listener =   array();
        return true;
    }

    /**
     * convert node
     *
     * transform namespaced tags to HTML
     *
     * @todo convert empty namespace (standard HTML) to known WB namespace, if possible
     * @param string $ns
     * @param string $tag
     * @param array $node
     */
    protected function convert($ns, $tag, &$node)
    {
        $con    =   $this->getConverter($ns, $tag);
        if (!$con) {
            return '';
        }
        if (!empty($this->tmplDir)) {
            $con->setTmplDir($this->tmplDir);
        }
        return $con->toHtml($node);
    }

    /**
     * convert node of default namespace
     *
     * @param string $tag
     * @param array $node
     */
    protected function convertDefault($tag, &$node)
    {
        if (!$this->tmpl || !$this->tmpl->exists('snippet_' . $tag)) {
            $this->handleBr($node);
            $this->insertAutoLink($node);
            return;
        }

        $html   =   array(
                        'ns'            =>  null,
                        'tag'           =>  '',
                        'attributes'    =>  array(),
                        'isEmpty'       =>  false,
                        'cData'         =>  array()
                    );
        $cData  =   implode('', $node['cData']);
        $this->tmpl->clearTemplate('snippet_' . $tag);
        $this->tmpl->addVar('snippet_' . $tag, 'cdata', $cData);

        $html['cData'][]    =   $this->tmpl->getParsedTemplate('snippet_' . $tag);
        $node   =   $html;
    }

    /**
     * Handle BR
     *
     * Either strip or keep BR-tags
     *
     * @param array $node
     */
    private function handleBr(&$node)
    {
        if (!empty($node['ns']) || 'br' != $node['tag']) {
            return;
        }

        $action =   $this->config->get('html/br/convert', 'keep');
        switch (strtolower($action)) {
            case 'strip':
                $node   =   array(
                                'ns'            =>  null,
                                'tag'           =>  '',
                                'attributes'    =>  array(),
                                'isEmpty'       =>  false,
                                'cData'         =>  array()
                            );
                break;

            default:
            case 'keep':
                break;
        }
    }

    /**
     * add auto links for each headline
     *
     * See in config whether to add a link to this tag.
     *
     * @param array $node
     */
    private function insertAutoLink(&$node)
    {
        // only headline tags h1-h6
        if (!empty($node['ns']) || !in_array($node['tag'], array('h1', 'h2', 'h3', 'h4', 'h5', 'h6'))) {
            return;
        }

        $tags   =   $this->config->get('html/heading/autolink/tag', array());
        $title  =   $this->config->get('html/heading/autolink/title', 'Link to paragraph %s');

        $cData  =   $node['cData'];
        $cData  =   implode("\n", $cData);
        $cData  =   strip_tags($cData);
        $cData  =   str_replace('&nbsp;', ' ', $cData);
        $cData  =   trim($cData);
        $title  =   sprintf($title, $cData);
        $cData  =   substr($cData, 0, 40);
        $cData  =   urlencode($cData);
        array_unshift($node['cData'], '<a name="'.$cData.'"></a>');
        if (empty($tags)) {
            return;
        }

        if (!in_array($node['tag'], $tags)) {
            return;
        }

        $class  =   $this->config->get('html/heading/autolink/class', 'wxml paragraph');
        $cd     =   $this->config->get('html/heading/autolink/cdata', '&para;');
        array_push($node['cData'], sprintf('<a class="%s" title="%s" href="#%s">%s</a>', $class, $title, $cData, $cd));
    }

    /**
     * replace URL string with propper node
     *
     * @see preg_replace_callback()
     * @param array $match
     * @return string
     */
    public function replaceUrlString($match)
    {
        // convert URL to node
        $atts   =   array(
                        'type'  =>  'external',
                        'href'  =>  $match[1] . '://' . $match[2] . $match[4],
                        'title' =>  ''
                    );

        // parameter?
        if (isset($match[5])) {
            $atts['href']   .=  '?' . $match[5];
        }
        $atts['title']  =   urldecode($atts['href']);

        $this->onStartElement('wb', 'a', $atts, false);
        $this->doc[$this->depth]['cData'][] =   $atts['title'];
        $this->onEndElement('wb', 'a', false);
        return array_pop($this->doc[$this->depth]['cData']);
    }
}