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


/**
 * Datasource Reference
 *
 * Things that refer to other things :-)
 *
 * @version 0.1.0
 * @package wb
 * @subpackage Markup
 */
class WBDatasource_Reference extends WBStdClass implements WBDatasource_Callback
{
    /**
     * table name: reference
     */
    const TABLE_REFERENCE = 'reference';

    /**
     * table name: dictionary url
     */
    const TABLE_URL = 'url';

    /**
     *
     * @var WBDatasource_Table
     */
    private $table;

    /**
     * URL
     * @var WBDictionary_URL
     */
    private $url;

    /**
     * Additional URL path in page layout
     * @var string
     */
    private $urlPath;

    /**
     * Current list of references
     * @var array
     */
    private $list;

    /**
     * current default namespace
     * @var string
     */
    private $ns = '';

    /**
     * current default tag
     * @var string
     */
    private $tag = '';

    /**
     * Resolve URL id to actual URL string
     * @var bool
     */
    private $urlResolve = true;

    /**
     * URLs primary key column in database
     * @var string
     */
    private $urlPrimary;

    /**
     * Config
     * @var WBConfig
     */
    private $config;

    /**
     * Constructor
     *
     * Init table access
     */
    public function __construct($parameter = array())
    {
        WBClass::load('WBDatasource_Table'
            , 'WBDictionary_URL');

        $this->table        =   WBClass::create('WBDatasource_Table');
        $this->url          =   WBClass::create('WBDictionary_URL');

        $this->urlPrimary   =   $this->table->getIdentifier('url');

        $this->config       =   WBClass::create('WBConfig');
        $this->config->load('vfs/dereferer', true);
    }

    /**
     * Set namespace
     *
     * @param string $ns
     * @return WBDatasource_Reference self
     */
    public function setNamespace($ns = '')
    {
        $this->ns   =   $ns;
        return $this;
    }

    /**
     * Set tag
     *
     * @param string $ns
     * @return WBDatasource_Reference self
     */
    public function setTag($tag = '')
    {
        $this->tag  =   $tag;
        return $this;
    }

    /**
     * Set list of references for id
     *
     * @param string $id
     * @param string $ns namespace (optionally)
     * @param string $tag tag (optionally)
     * @return array
     */
    public function get($id, $tag = null, $ns = null)
    {
        if (!isset($ns)) {
            $ns     =   $this->ns;
        }
        if (!isset($tag)) {
            $tag    =   $this->tag;
        }

        $clause         =   array();
        $clause[]       =   array(
                                'field' =>  'xid',
                                'value' =>  $id
                            );
        $clause[]       =   array(
                                'field' =>  'xtag',
                                'value' =>  $tag
                            );
        $clause[]       =   array(
                                'field' =>  'xnamespace',
                                'value' =>  $ns
                            );

        $options    =   array(
                                'callback'  =>  $this
                            );
        $list       =   $this->table->get(self::TABLE_REFERENCE, null, null, $clause, $options);

        // additional sources
        $sources    =   $this->config->get('sources/' . $this->ns, array());
        foreach ($sources as $src) {
        
        }

        return $list;
    }


    /**
     * Set URL target for reference
     *
     * Set either object, URLid or simply just the URL-string
     *
     * @param WBDictionary_URL $url
     * @param string $path
     * @return WBDatasource_Reference self
     */
    public function setUrl($url, $path = '')
    {
        $this->urlPath  =   $path;
        if ($url instanceof WBDictionary_URL) {
            $this->url  =   $url;
            return $this;
        }

        if (preg_match('/^d+$/', $url)) {
            $this->url->load($url);
            return $this;
        }
        $this->url->addWord($url);
        return $this;
    }

    /**
     * Add id to reference list
     *
     * @see save()
     * @param string $id
     * @param string $ns namespace (optionally)
     * @param string $tag tag (optionally)
     * @return array
     */
    public function add($id, $tag = null, $ns = null)
    {
        if (!isset($ns)) {
            $ns     =   $this->ns;
        }
        if (!isset($tag)) {
            $tag    =   $this->tag;
        }
        $this->list[]   =   array(
                                'xid'           =>  $id,
                                'xtag'          =>  $tag,
                                'xnamespace'    =>  $ns
                            );

    }

    /**
     * Save Current Records
     *
     * Delete old records,
     * Add current records
     * Flush list
     */
    public function save()
    {
        $this->deleteRecords();
        $this->addRecords($this->list);
        $this->list =   array();
    }

    /**
     * Add Records to Reference Table
     *
     * Store list in database
     *
     * @param array $list
     */
    private function addRecords($list)
    {
        $proto      =   array(
                            $this->urlPrimary   =>  $this->url->getId(),
                            'path'              =>  $this->urlPath,
                            'xnamespace'        =>  '',
                            'xtag'              =>  '',
                            'xid'               =>  ''
                    );
        $save   =   array();
        foreach ($list as $l) {
            $save[] =   array_merge($proto, $l);
        }

        // nothing to save
        if (empty($save)) {
            return;
        }
        $this->table->save(self::TABLE_REFERENCE, '__new', $save);
    }

    /**
     * Delete Stored Records
     *
     * Remove all references to current URL
     */
    private function deleteRecords()
    {
        $clause     =   array();
        $clause[]   =   array(
                            'field' =>  $this->urlPrimary,
                            'value' =>  $this->url->getId()
                            );
        $clause[]   =   array(
                            'field' =>  'path',
                            'value' =>  $this->urlPath
                        );
        $this->table->delete(self::TABLE_REFERENCE, null, null, $clause);

    }

   /**
    * Callback when receive whole entry
    *
    * @param string $src name of source
    * @param string $key
    * @param array $data loaded data
    * @return bool true on success
    */
    public function onDatasourceGet($src, $key, &$data)
    {
        if (self::TABLE_REFERENCE != $src || !$this->urlResolve) {
            return true;
        }

        // resolve URL
        $this->url->load($data[$this->urlPrimary]);
        $data['url']    =   $this->url->getWord();
        $data['page']   =   $data['url'];
        $page       =   explode('/', $data['page']);
        if (2 < count($page)) {
            $data['page']  =   urldecode(array_pop($page));
        }

        $all    =   $this->url->get();
        $data['title']  =   $all['title'];

        return true;
    }
}