feat(labs): super editor (#2001)

packages/web/src/javascripts/Components/NoteView/Controller/ItemGroupController.ts

@@ -0,0 +1,117 @@
+import { WebApplication } from '@/Application/Application'
+import { removeFromArray } from '@standardnotes/utils'
+import { FileItem, SNNote } from '@standardnotes/snjs'
+import { NoteViewController } from './NoteViewController'
+import { FileViewController } from './FileViewController'
+import { TemplateNoteViewControllerOptions } from './TemplateNoteViewControllerOptions'
+
+type ItemControllerGroupChangeCallback = (activeController: NoteViewController | FileViewController | undefined) => void
+
+export class ItemGroupController {
+  public itemControllers: (NoteViewController | FileViewController)[] = []
+  changeObservers: ItemControllerGroupChangeCallback[] = []
+  eventObservers: (() => void)[] = []
+
+  constructor(private application: WebApplication) {}
+
+  public deinit(): void {
+    ;(this.application as unknown) = undefined
+
+    this.eventObservers.forEach((removeObserver) => {
+      removeObserver()
+    })
+
+    this.changeObservers.length = 0
+
+    for (const controller of this.itemControllers) {
+      this.closeItemController(controller, { notify: false })
+    }
+
+    this.itemControllers.length = 0
+  }
+
+  async createItemController(context: {
+    file?: FileItem
+    note?: SNNote
+    templateOptions?: TemplateNoteViewControllerOptions
+  }): Promise<NoteViewController | FileViewController> {
+    if (this.activeItemViewController) {
+      this.closeItemController(this.activeItemViewController, { notify: false })
+    }
+
+    let controller!: NoteViewController | FileViewController
+
+    if (context.file) {
+      controller = new FileViewController(this.application, context.file)
+    } else if (context.note) {
+      controller = new NoteViewController(this.application, context.note)
+    } else if (context.templateOptions) {
+      controller = new NoteViewController(this.application, undefined, context.templateOptions)
+    } else {
+      throw Error('Invalid input to createItemController')
+    }
+
+    this.itemControllers.push(controller)
+
+    await controller.initialize()
+
+    this.notifyObservers()
+
+    return controller
+  }
+
+  public closeItemController(
+    controller: NoteViewController | FileViewController,
+    { notify = true }: { notify: boolean } = { notify: true },
+  ): void {
+    controller.deinit()
+
+    removeFromArray(this.itemControllers, controller)
+
+    if (notify) {
+      this.notifyObservers()
+    }
+  }
+
+  closeActiveItemController(): void {
+    const activeController = this.activeItemViewController
+
+    if (activeController) {
+      this.closeItemController(activeController, { notify: true })
+    }
+  }
+
+  closeAllItemControllers(): void {
+    for (const controller of this.itemControllers) {
+      this.closeItemController(controller, { notify: false })
+    }
+
+    this.notifyObservers()
+  }
+
+  get activeItemViewController(): NoteViewController | FileViewController | undefined {
+    return this.itemControllers[0]
+  }
+
+  /**
+   * Notifies observer when the active controller has changed.
+   */
+  public addActiveControllerChangeObserver(callback: ItemControllerGroupChangeCallback): () => void {
+    this.changeObservers.push(callback)
+
+    if (this.activeItemViewController) {
+      callback(this.activeItemViewController)
+    }
+
+    const thislessChangeObservers = this.changeObservers
+    return () => {
+      removeFromArray(thislessChangeObservers, callback)
+    }
+  }
+
+  private notifyObservers(): void {
+    for (const observer of this.changeObservers) {
+      observer(this.activeItemViewController)
+    }
+  }
+}