<?php
/**
 * DokuWiki Plugin struct (Action Component)
 *
 * @license GPL 2 http://www.gnu.org/licenses/gpl-2.0.html
 * @author  Andreas Gohr, Michael Große <dokuwiki@cosmocode.de>
 */

// must be run within Dokuwiki
use plugin\struct\meta\Schema;
use plugin\struct\meta\StructException;

if(!defined('DOKU_INC')) die();

class action_plugin_struct_ajax extends DokuWiki_Action_Plugin {

    /**
     * Registers a callback function for a given event
     *
     * @param Doku_Event_Handler $controller DokuWiki's event controller object
     * @return void
     */
    public function register(Doku_Event_Handler $controller) {
        $controller->register_hook('AJAX_CALL_UNKNOWN', 'BEFORE', $this, 'handle_ajax');
    }

    /**
     * Pass Ajax call to a type
     *
     * @param Doku_Event $event event object by reference
     * @param mixed $param [the parameters passed as fifth argument to register_hook() when this
     *                           handler was registered]
     * @return bool
     */
    public function handle_ajax(Doku_Event $event, $param) {
        if($event->data != 'plugin_struct') return;
        $event->preventDefault();
        $event->stopPropagation();

        header('Content-Type: application/json');
        try {
            $result = $this->executeTypeAjax();
        } catch(StructException $e) {
            $result = array(
                'error' => $e->getMessage()
            );
            http_status(500);
        }

        $json = new JSON;
        echo $json->encode($result);
    }

    /**
     * Check the input variables and run the AJAX call
     *
     * @throws StructException
     * @return mixed
     */
    protected function executeTypeAjax() {
        global $INPUT;

        $col = $INPUT->str('column');
        if(blank($col)) throw new StructException('No column provided');
        list($schema, $colname) = explode('.', $col, 2);
        if(blank($schema) || blank($colname)) throw new StructException('Column format is wrong');

        $schema = new Schema($schema);
        if(!$schema->getId()) throw new StructException('Unknown Schema');

        $column = $schema->findColumn($colname);
        if($column === false) throw new StructException('Column not found');

        return $column->getType()->handleAjax();
    }
}