<?php
// This file is part of the Studyplan plugin for Moodle
//
// 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 <https://www.gnu.org/licenses/>.
/**
 * Class to abstract information about (category) context for web service export
 * @package    local_treestudyplan
 * @copyright  2023 P.M. Kuipers
 * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

namespace local_treestudyplan;
use \context;

/**
 * Class to abstract information about (category) context for web service export
 */
class contextinfo {
    /** @var context */
    public $context;

    /**
     * Create new based on context
     * @param context $context The context to describe
     */
    public function __construct(context $context) {
        $this->context = $context;
    }

    /**
     * Describe the result for the webservice model
     * @param int $value Webservice requirement constant
     * @return external_single_structure Webservice output structure
     */
    public static function structure($value = VALUE_REQUIRED) {
        return new \external_single_structure([
            "name" => new \external_value(PARAM_TEXT, 'context name'),
            "shortname" => new \external_value(PARAM_TEXT, 'context short name'),
            "path" => new \external_multiple_structure( new \external_value(PARAM_TEXT)),
            "shortpath" => new \external_multiple_structure( new \external_value(PARAM_TEXT)),
        ], 'context information', $value);
    }

    /**
     * Make the webservice result model
     * @return array Webservice value
     */
    public function model() {

        $ctxpath = array_reverse($this->context->get_parent_context_ids(true));
        if (count($ctxpath) > 1 && $ctxpath[0] == 1) {
            array_shift($ctxpath);
        }
        return  [
            "name" => $this->context->get_context_name(false, false),
            "shortname" => $this->context->get_context_name(false, true),
            "path" => array_map(function($c) {
                return \context::instance_by_id($c)->get_context_name(false, false);
            }, $ctxpath),
            "shortpath" => array_map(function($c) {
                return \context::instance_by_id($c)->get_context_name(false, true);
            }, $ctxpath),
        ];
    }

    /**
     * Make new Contextinfo for context id
     * @param int $contextid Context id
     * @return self Contextinfo based on context id
     */
    public static function by_id($contextid): self {
        return new self(self::context_by_id($contextid));
    }

    /**
     * Find context by id, but also return system context for context id 0
     * @param int $contextid Context id
     * @return context The context
     */
    private static function context_by_id($contextid): \context {
        if ($contextid <= 1) {
            $contextid = 1;
        }
        return \context::instance_by_id($contextid);
    }

}