MDL-84009 tool_mfa: Additional factor instances support

admin/tool/mfa/action.php

@@ -169,6 +169,17 @@ switch ($action) {
         echo $OUTPUT->heading(get_string('managefactor', 'factor_' . $factorobject->name));
         echo $OUTPUT->active_factors($factor);
         echo $OUTPUT->single_button($returnurl, get_string('back'));
+
+        // Displays a setup additional button in case it is needed.
+        if ($factorobject->show_additional_setup_button()) {
+            echo $OUTPUT->single_button(
+                url: new \moodle_url('action.php', ['action' => 'setup', 'factor' => $factor]),
+                label:  $factorobject->get_additional_setup_string(),
+                method: 'post',
+                options: ['type' => 'primary'],
+            );
+        }
+
         // JS for modal confirming replace and revoke actions.
         $PAGE->requires->js_call_amd('tool_mfa/confirmation_modal', 'init', [$context->id]);
 

admin/tool/mfa/classes/local/factor/object_factor_base.php

@@ -421,6 +421,18 @@ abstract class object_factor_base implements object_factor {
         return $this->has_setup();
     }
 
+    /**
+     * Returns true if a button should be shown to add factors of the same kind on the preferences page.
+     * For example, give user's the ability to set up multiple security keys.
+     *
+     * Override in child class if necessary.
+     *
+     * @return bool
+     */
+    public function show_additional_setup_button(): bool {
+        return false;
+    }
+
     /**
      * Returns true if a factor requires input from the user to verify.
      *
@@ -578,6 +590,18 @@ abstract class object_factor_base implements object_factor {
         return get_string('setupfactor', 'tool_mfa');
     }
 
+    /**
+     * Gets the string for additional setup button on preferences page.
+     * If the user has the ability to set up multiple security keys.
+     *
+     * Override in child class if necessary.
+     *
+     * @return string
+     */
+    public function get_additional_setup_string(): string {
+        return get_string('setupfactorbuttonadditional', 'tool_mfa');
+    }
+
     /**
      * Gets the string for manage button on preferences page.
      *

admin/tool/mfa/lang/en/tool_mfa.php

@@ -151,6 +151,7 @@ $string['settings:redir_exclusions_help'] = 'Each new line is a relative URL fro
 $string['settings:weight'] = 'Factor weight';
 $string['settings:weight_help'] = 'The weight of this factor if passed. A user needs at least 100 points to log in.';
 $string['setupfactor'] = 'Set up factor';
+$string['setupfactorbuttonadditional'] = 'Add additional factor';
 $string['setuprequired'] = 'User setup';
 $string['state:fail'] = 'Fail';
 $string['state:locked'] = 'Locked';