From f62874d87b659050001521b42a9ef7008f74488c Mon Sep 17 00:00:00 2001
From: Mohammad Farouk <phun.for.physics@gmail.com>
Date: Thu, 3 Oct 2024 17:57:24 +0300
Subject: [PATCH] Add overrides class

---
 classes/restriction/overrides.php | 151 ++++++++++++++++++++++++++++++
 1 file changed, 151 insertions(+)
 create mode 100644 classes/restriction/overrides.php

diff --git a/classes/restriction/overrides.php b/classes/restriction/overrides.php
new file mode 100644
index 00000000..8505065b
--- /dev/null
+++ b/classes/restriction/overrides.php
@@ -0,0 +1,151 @@
+<?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/>.
+
+namespace enrol_wallet\restriction;
+
+/**
+ * Class overrides
+ *
+ * @package    enrol_wallet
+ * @copyright  2024 Mohammad Farouk <phun.for.physics@gmail.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class overrides {
+    /**
+     * The database table name.
+     * @var string
+     */
+    public const TABLE = 'enrol_wallet_overrides';
+
+    /**
+     * Check if the user has an override from been restricted in this instance.
+     * @param int $instanceid
+     * @param int $userid
+     * @return bool
+     */
+    public static function is_instance_overridden($instanceid, $userid = 0) {
+        $rules = self::get_instance_overridden_rules($instanceid, $userid);
+        return !empty($rules) && !empty($rules['restrictions']);
+    }
+
+    /**
+     * Get restriction rules for an instance for a given user.
+     * @param int $instanceid
+     * @param int $userid
+     * @return array|null
+     */
+    public static function get_instance_overridden_rules($instanceid, $userid = 0) {
+        global $DB, $USER, $CFG;
+        if (empty($userid)) {
+            $userid = $USER->id;
+        }
+
+        if (isguestuser($userid)) {
+            return null;
+        }
+
+        // Check if this user is a part of an overridden cohort.
+        require_once($CFG->dirroot . '/cohort/lib.php');
+        $usercohorts = cohort_get_user_cohorts($userid);
+        $cohortsids = [];
+        foreach ($usercohorts as $cohort) {
+            $cohortsids[] = $cohort->id;
+        }
+        unset($usercohorts);
+
+        $cohortsids = array_unique($cohortsids);
+        [$cohortsin, $cohortsparams] = $DB->get_in_or_equal($cohortsids, SQL_PARAMS_NAMED);
+        $sql = "SELECT id, rules
+                FROM {enrol_wallet_overrides}
+                WHERE (userid = :userid
+                       OR cohortid $cohortsin)
+                  AND thing = :enrol
+                  AND thingid = :instanceid";
+
+        $params = [
+            'userid' => $userid,
+            'thing'  => 'enrol',
+            'thingid' => $instanceid,
+        ] + $cohortsparams;
+
+        $records = $DB->get_records_sql($sql, $params);
+
+        if (count($records) > 1) {
+            $return = [];
+            foreach ($records as $r) {
+                $rules = json_decode($r->rules, true);
+                if (!empty($rules)) {
+                    // Merge the rules.
+                    foreach ($rules as $key => $bool) {
+                        if ((bool)$bool) {
+                            $return[$key] = true;
+                        }
+                    }
+                }
+            }
+            return $return;
+        } else {
+            $record = reset($records);
+            return json_decode($record->rules, true);
+        }
+    }
+
+    /**
+     * Override a user from restriction for an enrol wallet instance.
+     * @param int $instanceid
+     * @param int $id user id or cohort id if cohort set to true.
+     * @param bool $iscohort if this is a cohort overriding
+     * @return bool
+     */
+    public static function override_instance($instanceid, $id, $iscohort = false) {
+        global $DB, $USER;
+        $conditions = [
+            'thing'   => 'enrol',
+            'thingid' => $instanceid,
+        ];
+
+        if ($iscohort) {
+            $conditions['cohortid'] = $id;
+        } else {
+            $conditions['userid'] = $id;
+        }
+
+        if ($record = $DB->get_record(self::TABLE, $conditions)) {
+
+            $rules = json_decode($record->rules, true);
+            if (empty($rules)) {
+                $rules = [];
+            }
+
+            $rules['restriction'] = true;
+            $record->rules = json_encode($rules);
+            $record->timemodified = time();
+            $record->usermodified = $USER->id;
+
+            return $DB->update_record(self::TABLE, $record);
+        }
+        $rules = [
+            'restriction' => true,
+        ];
+        $record = $conditions + [
+            'timecreated'  => time(),
+            'timemodified' => time(),
+            'usermodified' => $USER->id,
+            'rules'        => json_encode($rules),
+        ];
+        return $DB->insert_record(self::TABLE, $record, false);
+    }
+}