<?php
// This file is part of the Query submission plugin
//
// 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/>.

namespace tool_brickfield\local\areas\core_question;

use core\event\question_created;
use core\event\question_updated;
use tool_brickfield\area_base;

/**

<  * Base class for various question-related areas



>  * Base class for various question-related areas.


 *
 * This is an abstract class so it will be skipped by manager when it finds all areas
 *
 * @package    tool_brickfield
 * @copyright  2020 onward: Brickfield Education Labs, www.brickfield.ie
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
abstract class base extends area_base {

    /**
     * Find recordset of the relevant areas.

>      *


     * @param \core\event\base $event
     * @return \moodle_recordset|null

<      * @throws \coding_exception
<      * @throws \dml_exception


     */
    public function find_relevant_areas(\core\event\base $event): ?\moodle_recordset {
        global $DB;

< 


        if (($event instanceof question_created) || ($event instanceof question_updated)) {

<             $rs = $DB->get_recordset_sql(
<                 "SELECT {$this->get_type()} AS type,



>             $sql = "SELECT {$this->get_type()} AS type,


                ctx.id AS contextid,
                {$this->get_standard_area_fields_sql()}

<                 t.id AS itemid,



>                        q.id AS itemid,


                {$this->get_course_and_cat_sql($event)}

<                 t.{$this->get_fieldname()} AS content
<             FROM {question} t
<             INNER JOIN {question_categories} qc ON qc.id = t.category
<             INNER JOIN {context} ctx ON ctx.id = qc.contextid
<             WHERE (t.id = :refid)
<             ORDER BY t.id",
<                 [
<                     'refid' => $event->objectid,
<                 ]);



>                        q.{$this->get_fieldname()} AS content
>                   FROM {question} q
>             INNER JOIN {question_versions} qv
>                     ON qv.questionid = q.id
>             INNER JOIN {question_bank_entries} qbe
>                     ON qbe.id = qv.questionbankentryid
>             INNER JOIN {question_categories} qc
>                     ON qc.id = qbe.questioncategoryid
>             INNER JOIN {context} ctx
>                     ON ctx.id = qc.contextid
>                  WHERE (q.id = :refid)
>               ORDER BY q.id";
> 
>             $rs = $DB->get_recordset_sql($sql, ['refid' => $event->objectid]);


            return $rs;
        }
        return null;
    }

    /**
     * Find recordset of the course areas.

>      *


     * @param int $courseid
     * @return \moodle_recordset

<      * @throws \coding_exception
<      * @throws \dml_exception


     */
    public function find_course_areas(int $courseid): ?\moodle_recordset {
        global $DB;

< 


        $coursecontext = \context_course::instance($courseid);

<         return $DB->get_recordset_sql(
<             "SELECT {$this->get_type()} AS type,
<                 ctx.id AS contextid,
<                 {$this->get_standard_area_fields_sql()}
<                 t.id AS itemid,
<                 {$courseid} AS courseid,
<                 null AS categoryid,
<                 t.{$this->get_fieldname()} AS content
<             FROM {question} t
<             INNER JOIN {question_categories} qc ON qc.id = t.category
<             INNER JOIN {context} ctx ON ctx.id = qc.contextid
<             WHERE (ctx.contextlevel = :ctxcourse AND ctx.id = qc.contextid AND ctx.instanceid = :courseid) OR
<                 (ctx.contextlevel = :module AND {$DB->sql_like('ctx.path', ':coursecontextpath')})
<             ORDER BY t.id ASC",
<             [



>         $param = [


                'ctxcourse' => CONTEXT_COURSE,
                'courseid' => $courseid,
                'module' => CONTEXT_MODULE,
                'coursecontextpath' => $DB->sql_like_escape($coursecontext->path) . '/%',

<             ]);



>         ];
> 
>         $sql = "SELECT {$this->get_type()} AS type,
>                        ctx.id AS contextid,
>                        {$this->get_standard_area_fields_sql()}
>                        q.id AS itemid,
>                        {$courseid} AS courseid,
>                        null AS categoryid,
>                        q.{$this->get_fieldname()} AS content
>                   FROM {question} q
>             INNER JOIN {question_versions} qv
>                     ON qv.questionid = q.id
>             INNER JOIN {question_bank_entries} qbe
>                     ON qbe.id = qv.questionbankentryid
>             INNER JOIN {question_categories} qc
>                     ON qc.id = qbe.questioncategoryid
>             INNER JOIN {context} ctx
>                     ON ctx.id = qc.contextid
>                  WHERE (ctx.contextlevel = :ctxcourse
>                    AND ctx.id = qc.contextid
>                    AND ctx.instanceid = :courseid)
>                     OR (ctx.contextlevel = :module
>                    AND {$DB->sql_like('ctx.path', ':coursecontextpath')})
>               ORDER BY q.id ASC";
> 
>         return $DB->get_recordset_sql($sql, $param);


    }

    /**
     * Return an array of area objects that contain content at the site and system levels only. This would be question content from
     * question categories at the system context only.

>      *


     * @return \moodle_recordset

<      * @throws \dml_exception


     */
    public function find_system_areas(): ?\moodle_recordset {
        global $DB;

< 
<         $select = 'SELECT ' . $this->get_type() . ' AS type, qc.contextid AS contextid, ' . $this->get_standard_area_fields_sql() .
<             ' t.id AS itemid, ' . SITEID . ' as courseid, cc.id as categoryid,' .
<             ' t.'.$this->get_fieldname().' AS content ';
<         $from = 'FROM {question} t ' .
<             'INNER JOIN {question_categories} qc ON qc.id = t.category ' .
<             'INNER JOIN {context} ctx ON ctx.id = qc.contextid ' .
<             'LEFT JOIN {course_categories} cc ON cc.id = ctx.instanceid AND ctx.contextlevel = :coursecat ';
<         $where = 'WHERE (ctx.contextlevel = :syscontext) OR (ctx.contextlevel = :coursecat2) ';
<         $order = 'ORDER BY t.id';


        $params = [
            'syscontext' => CONTEXT_SYSTEM,
            'coursecat' => CONTEXT_COURSECAT,
            'coursecat2' => CONTEXT_COURSECAT,
        ];


<         return $DB->get_recordset_sql($select . $from . $where . $order, $params);



>         $sql = "SELECT {$this->get_type()} AS type,
>                        qc.contextid AS contextid,
>                        {$this->get_standard_area_fields_sql()}
>                        q.id AS itemid,
>                        " . SITEID . "  as courseid,
>                        cc.id as categoryid,
>                        q.{$this->get_fieldname()} AS content
>                   FROM {question} q
>             INNER JOIN {question_versions} qv
>                     ON qv.questionid = q.id
>             INNER JOIN {question_bank_entries} qbe
>                     ON qbe.id = qv.questionbankentryid
>             INNER JOIN {question_categories} qc
>                     ON qc.id = qbe.questioncategoryid
>             INNER JOIN {context} ctx
>                     ON ctx.id = qc.contextid
>              LEFT JOIN {course_categories} cc
>                     ON cc.id = ctx.instanceid
>                    AND ctx.contextlevel = :coursecat
>                  WHERE (ctx.contextlevel = :syscontext)
>                     OR (ctx.contextlevel = :coursecat2)
>               ORDER BY q.id";
> 
>         return $DB->get_recordset_sql($sql, $params);


    }

    /**
     * Returns the moodle_url of the page to edit the error.

>      *


     * @param \stdClass $componentinfo
     * @return \moodle_url

<      * @throws \moodle_exception


     */
    public static function get_edit_url(\stdClass $componentinfo): \moodle_url {
        $questionid = $componentinfo->itemid;

<         // Question answers are editable on main question page



>         // Question answers are editable on main question page.


        // Hence, use refid for these links.

<         if ($componentinfo->tablename == 'question_answers') {



>         if ($componentinfo->tablename === 'question_answers') {


            $questionid = $componentinfo->refid;
        }
        // Default to SITEID if courseid is null, i.e. system or category level questions.
        $thiscourseid = ($componentinfo->courseid !== null) ? $componentinfo->courseid : SITEID;

<         return new \moodle_url('/question/question.php', ['courseid' => $thiscourseid, 'id' => $questionid]);



>         return new \moodle_url('/question/bank/editquestion/question.php', ['courseid' => $thiscourseid, 'id' => $questionid]);


    }

    /**
     * Determine the course and category id SQL depending on the specific context associated with question data.

>      *


     * @param \core\event\base $event
     * @return string

<      * @throws \dml_exception


     */
    protected function get_course_and_cat_sql(\core\event\base $event): string {

<         global $DB;
< 


        $courseid = 'null';
        $catid = 'null';


<         $sql = "
<                 SELECT ctx.instanceid, cm.course as courseid, ctx.contextlevel
<                 FROM {question} q
<                 INNER JOIN {question_categories} qc ON qc.id = q.category
<                 INNER JOIN {context} ctx ON ctx.id = qc.contextid
<                 LEFT JOIN {course_modules} cm ON cm.id = ctx.instanceid AND ctx.contextlevel = :coursemodule
<                 WHERE q.id = :refid
<             ";
<         $params = [
<             'coursemodule' => CONTEXT_MODULE,
<             'refid' => $event->objectid,
<         ];
< 
<         if ($record = $DB->get_record_sql($sql, $params)) {



>         if ($record = self::get_course_and_category(CONTEXT_MODULE, $event->objectid)) {


            if ($record->contextlevel == CONTEXT_MODULE) {
                $courseid = $record->courseid;
            } else if ($record->contextlevel == CONTEXT_COURSE) {
                $courseid = $record->instanceid;
            } else if ($record->contextlevel == CONTEXT_COURSECAT) {
                $catid = $record->instanceid;
            } else if ($record->contextlevel == CONTEXT_SYSTEM) {
                $courseid = 1;
            }
        }

        return "
            {$courseid} AS courseid,
            {$catid} AS categoryid,
        ";

>     }
    }
> 
}
>     /**
>      * Get the course and category data for the question.
>      *
>      * @param int $coursemodule
>      * @param int $refid
>      * @return \stdClass|false
>      */
>     public static function get_course_and_category($coursemodule, $refid) {
>         global $DB;
> 
>         $sql = 'SELECT ctx.instanceid,
>                        cm.course as courseid,
>                        ctx.contextlevel
>                   FROM {question} q
>             INNER JOIN {question_versions} qv
>                     ON qv.questionid = q.id
>             INNER JOIN {question_bank_entries} qbe
>                     ON qbe.id = qv.questionbankentryid
>             INNER JOIN {question_categories} qc
>                     ON qc.id = qbe.questioncategoryid
>             INNER JOIN {context} ctx
>                     ON ctx.id = qc.contextid
>              LEFT JOIN {course_modules} cm
>                     ON cm.id = ctx.instanceid
>                    AND ctx.contextlevel = :coursemodule
>                  WHERE q.id = :refid';
>         $params = [
>                 'coursemodule' => $coursemodule,
>                 'refid' => $refid
>         ];
>         return $DB->get_record_sql($sql, $params);