Switched tag unsaved changes modal to new modal pattern

refs https://github.com/TryGhost/Team/issues/1734
refs https://github.com/TryGhost/Team/issues/559
refs https://github.com/TryGhost/Ghost/issues/14101

- switches to newer modal patterns ready for later Ember upgrades

ghost/admin/app/controllers/tag.js

@@ -3,15 +3,12 @@ import DeleteTagModal from '../components/tags/delete-tag-modal';
 import {action} from '@ember/object';
 import {inject as service} from '@ember/service';
 import {task} from 'ember-concurrency';
-import {tracked} from '@glimmer/tracking';
 
 export default class TagController extends Controller {
     @service modals;
     @service notifications;
     @service router;
 
-    @tracked showUnsavedChangesModal;
-
     get tag() {
         return this.model;
     }
@@ -23,37 +20,6 @@ export default class TagController extends Controller {
         });
     }
 
-    @action
-    toggleUnsavedChangesModal(transition) {
-        let leaveTransition = this.leaveScreenTransition;
-
-        if (!transition && this.showUnsavedChangesModal) {
-            this.leaveScreenTransition = null;
-            this.showUnsavedChangesModal = false;
-            return;
-        }
-
-        if (!leaveTransition || transition.targetName === leaveTransition.targetName) {
-            this.leaveScreenTransition = transition;
-
-            // if a save is running, wait for it to finish then transition
-            if (this.saveTask.isRunning) {
-                return this.saveTask.last.then(() => {
-                    transition.retry();
-                });
-            }
-
-            // we genuinely have unsaved data, show the modal
-            this.showUnsavedChangesModal = true;
-        }
-    }
-
-    @action
-    leaveScreen() {
-        this.tag.rollbackAttributes();
-        return this.leaveScreenTransition.retry();
-    }
-
     @task({drop: true})
     *saveTask() {
         let {tag} = this;

ghost/admin/app/routes/tag.js

@@ -1,7 +1,10 @@
 import AuthenticatedRoute from 'ghost-admin/routes/authenticated';
+import ConfirmUnsavedChangesModal from '../components/modals/confirm-unsaved-changes';
+import {action} from '@ember/object';
 import {inject as service} from '@ember/service';
 
 export default class TagRoute extends AuthenticatedRoute {
+    @service modals;
     @service router;
     @service session;
 
@@ -9,14 +12,6 @@ export default class TagRoute extends AuthenticatedRoute {
     // and refresh in the background
     _requiresBackgroundRefresh = true;
 
-    constructor() {
-        super(...arguments);
-
-        this.router.on('routeWillChange', (transition) => {
-            this.showUnsavedChangesModal(transition);
-        });
-    }
-
     beforeModel() {
         super.beforeModel(...arguments);
 
@@ -48,26 +43,49 @@ export default class TagRoute extends AuthenticatedRoute {
     }
 
     deactivate() {
-        super.deactivate(...arguments);
-
-        // clean up newly created records and revert unsaved changes to existing
-        this.controller.tag.rollbackAttributes();
-
         this._requiresBackgroundRefresh = true;
+
+        this.confirmModal = null;
+        this.hasConfirmed = false;
     }
 
-    showUnsavedChangesModal(transition) {
+    @action
-        if (transition.from && transition.from.name === this.routeName && transition.targetName) {
+    async willTransition(transition) {
-            let {controller} = this;
+        if (this.hasConfirmed) {
+            return true;
+        }
 
-            // tag.changedAttributes is always true for new tags but number of changed attrs is reliable
-            let isChanged = Object.keys(controller.tag.changedAttributes()).length > 0;
-
-            if (!controller.tag.isDeleted && isChanged) {
         transition.abort();
-                controller.toggleUnsavedChangesModal(transition);
+
+        // wait for any existing confirm modal to be closed before allowing transition
+        if (this.confirmModal) {
             return;
         }
+
+        if (this.controller.saveTask?.isRunning) {
+            await this.controller.saveTask.last;
         }
+
+        const shouldLeave = await this.confirmUnsavedChanges();
+
+        if (shouldLeave) {
+            this.controller.model.rollbackAttributes();
+            this.hasConfirmed = true;
+            return transition.retry();
+        }
+    }
+
+    async confirmUnsavedChanges() {
+        if (this.controller.model?.hasDirtyAttributes) {
+            this.confirmModal = this.modals
+                .open(ConfirmUnsavedChangesModal)
+                .finally(() => {
+                    this.confirmModal = null;
+                });
+
+            return this.confirmModal;
+        }
+
+        return true;
     }
 }

ghost/admin/app/templates/tag.hbs

@@ -28,11 +28,3 @@
         </div>
     {{/unless}}
 </section>
-
-{{#if this.showUnsavedChangesModal}}
-    <GhFullscreenModal
-        @modal="leave-settings"
-        @confirm={{this.leaveScreen}}
-        @close={{this.toggleUnsavedChangesModal}}
-        @modifier="action wide" />
-{{/if}}