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

WBClass::load('WBMarkup_Handler');

/**
 * Markup Scanner Handler: Validator
 *
 * Validate against policy
 *
 * @version 0.1.0
 * @package wb
 * @subpackage Markup
 */
class WBMarkup_Handler_Validator implements WBMarkup_Handler
{
    /**
     * @var WBConfig
     */
    private $policy;
    
    /**
     * List of errors
     * @var array
     */
    private $errors =   array();
    
    /**
     * List of validators
     * @var array
     */
    private $validators =   array();
        
    /**
     * Constructor 
     * 
     * Initialize configuration object
     */
    public function __construct($parameters = array())
    {
        $this->policy =   WBClass::create('WBConfig');
    }

    /**
     * Set Alternative Policy File
     * 
     * Use this method to load a different policy file than __default.
     * @see onScanStart()
     * @param string 
     */
    public function setPolicy($policy = '__default')
    {
        $this->policy->load('wxml/policy/' . $policy);
    }

   /**
    * Handler to be called right before scan starts
    *
    * Load validator policy if not done already
    *
    * @param string $content
    * @return bool usually true, false to stop the scanner
    */
    public function onScanStart(&$content)
    {
        if (!$this->policy->has()) {
            $this->policy->load('wxml/policy/__default');
        }
        
        $rules  =   $this->policy->get('policy/rule');
        foreach ($rules as $r) {
            $val    =   WBClass::create('WBMarkup_Validator_' . $r['validator']);
            if (isset($r['params']) && is_array($r['params'])) {
                $val->configure($r['params']);
            }
            $this->validators[] =   $val;
        }

        
        return true;
    }
    
   /**
    * Handler to be called for each opening tag
    *
    * Gonna be callled if the Scanner finds a StartElement
    *
    * @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, $isEmpty)
    {
        foreach ($this->validators as $i => $v) {
            if ($v->validateStartElement($ns, $tag, $attributes, $isEmpty)) {
                $code   =   $v->getErrorCode();
                if (0 < $code) {
                    $this->errors[] =   array(
                                                'code'  =>  $i * 10000 + $code,
                                                'msg'   =>  $v->getErrorMsg()
                                            );
                }
                break;
            }
        }

        return true;
    }
    
   /**
    * Handler to be called if character data comes in
    *
    * Gonna be called if the Scanner find cData
    *
    * @param string $cData = the cData
    * @return bool usually true, false to stop the scanner
    * @return bool usually true, false to stop the scanner
    */
    public function onCharacterData($cData)
    {
        return true;
    }
    
   /**
    * Handler to be called for each closing tag
    *
    * Gonna be called if the Scanner finds a EndElement
    *
    * @param string $ns    = The NameSpace
    * @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)
    {
        return true;
    }
        
   /**
    * Handler to be called when scanner reaches the end of input stream
    *
    * This function gonna be called when the Scanner was'nt
    * distrubed by the client and has finished scanning the
    * whole content string.
    *
    * @return bool usually true, false to stop the scanner
    */
    public function onScanComplete()
    {
        return true;
    }

   /**
    * Occurs if a entity element will be found inside cdata
    *
    * This function gonna be called if the scanner finds a entity element
    * like e.g. &nbsp; The Client may then decided want he wants to do with it
    *
    * @param $entity        = the entity without the surrounding & and ;, e.g. nbsp
    * @param $isUnicode = true if it is a unicode string, false if not
    *
    * @return bool usually true, false to stop the scanner
    */
    public function onEntityElement($entity, $isUnicode)
    {
        return true;
    }
    
   /**
    * Receive result
    *
    * This function is meant to be called after scan has completed and
    * everything went alright. getParsedContent() gives you access to
    * whatever this handler build up.
    *
    * @return mixed contente
    */
    public function getParsedContent()
    {
        return '';
    }
    
    /**
     * Get list of validation errors
     * 
     * @return array
     */
    public function getErrors()
    {
        return $this->errors;
    }
}