<?php

// This file is part of Moodle - http://moodle.org/
//
// Moodle 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, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Form for editing HTML block instances.
 *
 * @package   block_html
 * @copyright 1999 onwards Martin Dougiamas (http://dougiamas.com)
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

class block_html extends block_base {

    function init() {
        $this->title = get_string('pluginname', 'block_html');
    }

    function applicable_formats() {
        return array('all' => true);
    }

    function specialization() {
        $this->title = isset($this->config->title) ? format_string($this->config->title) : format_string(get_string('newhtmlblock', 'block_html'));
    }

    function instance_allow_multiple() {
        return true;
    }

    function get_content() {
        if ($this->content !== NULL) {
            return $this->content;
        }

        if ($this->content_is_trusted()) {
            // fancy html allowed only on course, category and system blocks.
            $filteropt = new stdClass;
            $filteropt->noclean = true;
        } else {
            $filteropt = null;
        }

        $this->content = new stdClass;
        $this->content->footer = '';
        if (isset($this->config->text)) {
            // rewrite url
            $this->config->text = file_rewrite_pluginfile_urls($this->config->text, 'pluginfile.php', $this->context->id, 'block_html', 'content', NULL);
            $this->content->text = format_text($this->config->text, $this->config->format, $filteropt);
        } else {
            $this->content->text = '';
        }

        unset($filteropt); // memory footprint

        return $this->content;
    }


    /**
     * Serialize and store config data
     */
    function instance_config_save($data, $nolongerused = false) {
        global $DB;

        $config = clone($data);
        // Move embedded files into a proper filearea and adjust HTML links to match
        $config->text = file_save_draft_area_files($data->text['itemid'], $this->context->id, 'block_html', 'content', 0, array('subdirs'=>true), $data->text['text']);
        $config->format = $data->text['format'];

        parent::instance_config_save($config, $nolongerused);
    }

    function instance_delete() {
        global $DB;
        $fs = get_file_storage();
        $fs->delete_area_files($this->context->id, 'block_html');
        return true;
    }

    function content_is_trusted() {
        global $SCRIPT;

        if (!$context = get_context_instance_by_id($this->instance->parentcontextid)) {
            return false;
        }
        //find out if this block is on the profile page
        if ($context->contextlevel == CONTEXT_USER) {
            if ($SCRIPT === '/my/index.php') {
                // this is exception - page is completely private, nobody else may see content there
                // that is why we allow JS here
                return true;
            } else {
                // no JS on public personal pages, it would be a big security issue
                return false;
            }
        }

        return true;
    }

    /**
     * Will be called before an instance of this block is backed up, so that any links in
     * any links in any HTML fields on config can be encoded.
     * @return string
     */
    function get_backup_encoded_config() {
        /// Prevent clone for non configured block instance. Delegate to parent as fallback.
        if (empty($this->config)) {
            return parent::get_backup_encoded_config();
        }
        $data = clone($this->config);
        $data->text = backup_encode_absolute_links($data->text);
        return base64_encode(serialize($data));
    }

    /**
     * This function makes all the necessary calls to {@link restore_decode_content_links_worker()}
     * function in order to decode contents of this block from the backup
     * format to destination site/course in order to mantain inter-activities
     * working in the backup/restore process.
     *
     * This is called from {@link restore_decode_content_links()} function in the restore process.
     *
     * NOTE: There is no block instance when this method is called.
     *
     * @param object $restore Standard restore object
     * @return boolean
     **/
    function decode_content_links_caller($restore) {
        global $CFG, $DB;

        if ($restored_blocks = $DB->get_records_select("backup_ids", "table_name = 'block_instance' AND backup_code = ? AND new_id > 0", array($restore->backup_unique_code), "", "new_id")) {
            $restored_blocks = implode(',', array_keys($restored_blocks));
            $sql = "SELECT bi.*
                      FROM {block_instance} bi
                           JOIN {block} b ON b.id = bi.blockid
                     WHERE b.name = 'html' AND bi.id IN ($restored_blocks)";

            if ($instances = $DB->get_records_sql($sql)) {
                foreach ($instances as $instance) {
                    $blockobject = block_instance('html', $instance);
                    $blockobject->config->text = restore_decode_absolute_links($blockobject->config->text);
                    $blockobject->config->text = restore_decode_content_links_worker($blockobject->config->text, $restore);
                    $blockobject->instance_config_commit();
                }
            }
        }

        return true;
    }
}