<?php

use oat\tao\helpers\Template;
use oat\tao\helpers\TreeHelper;

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; under version 2
 * of the License (non-upgradable).
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2008-2010 (original work) Deutsche Institut für Internationale Pädagogische Forschung (under the project TAO-TRANSFER);
 *               2009-2012 (update and modification) Public Research Centre Henri Tudor (under the project TAO-SUSTAIN & TAO-DEV);
 *
 */

/**
 * Helper to generate simple tree forms, that allow a user
 * to modify properties that have a resource range or domain
 *
 * @author Joel Bout, <joel@taotesting.com>
 * @package tao
 * @see core_kernel_classes_* packages

 */
class tao_helpers_form_GenerisTreeForm extends Renderer
{
    
    /**
     * Generates a form to define the values of a specific property for a resource
     *
     * @param core_kernel_classes_Resource $resource
     * @param core_kernel_classes_Property $property
     * @return tao_helpers_form_GenerisTreeForm
     */
    public static function buildTree(core_kernel_classes_Resource $resource, core_kernel_classes_Property $property)
    {
        $tree = new self($resource, $property);
        
        $range = $property->getRange();
        $tree->setData('rootNode', $range->getUri());
        $tree->setData('dataUrl', _url('getData', 'GenerisTree', 'tao'));
        $tree->setData('saveUrl', _url('setValues', 'GenerisTree', 'tao'));
        
        $values = $resource->getPropertyValues($property);
        $tree->setData('values', $values);
        $openNodeUris = TreeHelper::getNodesToOpen($values, $range);
        $tree->setData('openNodes', $openNodeUris);
        return $tree;
    }
    
    /**
     * Generates a form to define the reverse values of a specific property for a resource
     * This allows to set/remove multiple triples that share the same object
     *
     * @param core_kernel_classes_Resource $resource
     * @param core_kernel_classes_Property $property
     * @return tao_helpers_form_GenerisTreeForm
     */
    public static function buildReverseTree(core_kernel_classes_Resource $resource, core_kernel_classes_Property $property)
    {
        $tree = new self($resource, $property);
        
        $domainCollection = $property->getDomain();
        if (!$domainCollection->isEmpty()) {
            $domain = $domainCollection->get(0);
            $tree->setData('rootNode', $domain->getUri());
            $tree->setData('dataUrl', _url('getData', 'GenerisTree', 'tao'));
            $tree->setData('saveUrl', _url('setReverseValues', 'GenerisTree', 'tao'));
            
            $values = array_keys($domain->searchInstances([
                $property->getUri() => $resource
            ], ['recursive' => true, 'like' => false]));
            
            $tree->setData('values', $values);
            $openNodeUris = TreeHelper::getNodesToOpen($values, $domain);
            $tree->setData('openNodes', $openNodeUris);
        }
        return $tree;
    }
    
    /**
     * Should not be called directly but is public
     * since Renderer is public
     *
     * @param core_kernel_classes_Resource $resource
     * @param core_kernel_classes_Property $property
     */
    public function __construct(core_kernel_classes_Resource $resource, core_kernel_classes_Property $property)
    {
        $tpl = Template::getTemplate('form' . DIRECTORY_SEPARATOR . 'generis_tree_form.tpl', 'tao');
        parent::__construct($tpl);
        
        $this->setData('id', 'uid' . md5($property->getUri() . $resource->getUri()));
        $this->setData('title', $property->getLabel());
        
        $this->setData('resourceUri', $resource->getUri());
        $this->setData('propertyUri', $property->getUri());

        $this->setHiddenNodes([]);
    }

    /**
     * Set list of nodes id to be hidden
     *
     * @param Array $hiddenNodes
     */
    public function setHiddenNodes($hiddenNodes)
    {
        $this->setData('hiddenNodes', $hiddenNodes);
    }

    /**
     * Set the title of the tree widget
     *
     * @param string $title
     */
    public function setTitle($title)
    {
        $this->setData('title', $title);
    }
    
    /**
     * (non-PHPdoc)
     * @see Renderer::render()
     */
    public function render()
    {
        return parent::render();
    }
    
    public static function getSelectedInstancesFromPost()
    {
        $values = [];
        if (isset($_POST['instances'])) {
            $json = json_decode($_POST['instances']);
            if (!is_null($json)) {
                foreach ($json as $coded) {
                    $val = tao_helpers_Uri::decode($coded);
                    if (!empty($val)) {
                        $values[] = $val;
                    } else {
                        common_Logger::w('Empty URI in json array in ' . __FUNCTION__);
                    }
                }
            } else {
                common_Logger::w('json string could not be decoded in ' . __FUNCTION__);
            }
        } else {
            common_Logger::w('No post parameter instances in ' . __FUNCTION__);
        }
        // Make sure we return a set of unique URIs.
        return array_unique($values);
    }
}