Add choice for code format (#668)

Author: fulldecent

classes/certificate.php

@@ -539,23 +539,48 @@ public static function issue_certificate($certificateid, $userid) {
     }
 
     /**
-     * Generates a 10-digit code of random letters and numbers.
+     * Generates an unused code of random letters and numbers.
      *
      * @return string
      */
-    public static function generate_code() {
+    public static function generate_code(): string {
         global $DB;
 
-        $uniquecodefound = false;
-        $code = random_string(10);
-        while (!$uniquecodefound) {
-            if (!$DB->record_exists('customcert_issues', ['code' => $code])) {
-                $uniquecodefound = true;
-            } else {
-                $code = random_string(10);
-            }
-        }
+        // Get the user's selected method from settings.
+        $method = get_config('customcert', 'codegenerationmethod');
 
+        do {
+            $code = match ($method) {
+                '0' => self::generate_code_upper_lower_digits(),
+                '1' => self::generate_code_digits_with_hyphens(),
+                default => self::generate_code_upper_lower_digits(),
+            };
+        } while ($DB->record_exists('customcert_issues', ['code' => $code]));
         return $code;
     }
+
+    /**
+     * Generate a random code of the format XXXXXXXXXX, where each X is a character from the set [A-Za-z0-9].
+     * Does not check that it is unused.
+     *
+     * @return string
+     */
+    private static function generate_code_upper_lower_digits(): string {
+        return random_string(10);
+    }
+
+    /**
+     * Generate an random code of the format XXXX-XXXX-XXXX, where each X is a random digit.
+     * Does not check that it is unused.
+     *
+     * @return string
+     */
+    private static function generate_code_digits_with_hyphens(): string {
+        return sprintf(
+            '%04d-%04d-%04d',
+            random_int(0, 9999),
+            random_int(0, 9999),
+            random_int(0, 9999)
+        );
+    }
 }

lang/en/customcert.php

@@ -243,3 +243,7 @@
 $string['verifycertificatedesc'] = 'This link will take you to a new screen where you will be able to verify certificates on the site';
 $string['width'] = 'Width';
 $string['width_help'] = 'This is the width of the certificate PDF in mm. For reference an A4 piece of paper is 210mm wide and a letter is 216mm wide.';
+$string['codegenerationmethod'] = 'Code generation method';
+$string['codegenerationmethod_desc'] = 'Choose between the two methods for generating certificate codes.';
+$string['codegenerationmethod_upperlowerdigits'] = '6aOdbLEuoC (Upper/lower/digits random string)';
+$string['codegenerationmethod_digitshyphens'] = '0123-4567-8901 (Digits with hyphens)';

settings.php

@@ -81,6 +81,17 @@
 $settings->add(new admin_setting_heading('defaults',
     get_string('modeditdefaults', 'admin'), get_string('condifmodeditdefaults', 'admin')));
 
+$settings->add(new admin_setting_configselect(
+    'customcert/codegenerationmethod',
+    get_string('codegenerationmethod', 'customcert'),
+    get_string('codegenerationmethod_desc', 'customcert'),
+    0, // Default option (0 = Upper/lower/digits random string method).
+    [
+        0 => get_string('codegenerationmethod_upperlowerdigits', 'customcert'), // Upper/lower/digits random string.
+        1 => get_string('codegenerationmethod_digitshyphens', 'customcert')  // Digits with hyphens numeric code.
+    ]
+));
+
 $yesnooptions = [
     0 => get_string('no'),
     1 => get_string('yes'),