/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

import 'vs/css!./dropdown';
import { IAction, IActionRunner } from '../../../../../vs/base/common/actions';
import { IDisposable } from '../../../../../vs/base/common/lifecycle';
import { AnchorAlignment } from '../../../../../vs/base/browser/ui/contextview/contextview';
import { ResolvedKeybinding } from '../../../../../vs/base/common/keyCodes';
import { append, $ } from '../../../../../vs/base/browser/dom';
import { Emitter } from '../../../../../vs/base/common/event';
import {
  BaseActionViewItem,
  IBaseActionViewItemOptions,
} from '../../../../../vs/base/browser/ui/actionbar/actionViewItems';
import {
  IActionProvider,
  DropdownMenu,
  IDropdownMenuOptions,
  ILabelRenderer,
} from '../../../../../vs/base/browser/ui/dropdown/dropdown';
import { IContextMenuProvider } from '../../../../../vs/base/browser/contextmenu';
import { IActionViewItemProvider } from '../../../../../vs/base/browser/ui/actionbar/actionbar';

export interface IKeybindingProvider {
  (action: IAction): ResolvedKeybinding | undefined;
}

export interface IAnchorAlignmentProvider {
  (): AnchorAlignment;
}

export interface IDropdownMenuActionViewItemOptions
  extends IBaseActionViewItemOptions {
  readonly actionViewItemProvider?: IActionViewItemProvider;
  readonly keybindingProvider?: IKeybindingProvider;
  readonly actionRunner?: IActionRunner;
  readonly classNames?: string[] | string;
  readonly anchorAlignmentProvider?: IAnchorAlignmentProvider;
  readonly menuAsChild?: boolean;
}

export class DropdownMenuActionViewItem extends BaseActionViewItem {
  private menuActionsOrProvider: readonly IAction[] | IActionProvider;
  private dropdownMenu: DropdownMenu | undefined;
  private contextMenuProvider: IContextMenuProvider;
  private actionItem: HTMLElement | null = null;

  private _onDidChangeVisibility = this._register(new Emitter<boolean>());

  protected override readonly options: IDropdownMenuActionViewItemOptions;

  constructor(
    action: IAction,
    menuActionsOrProvider: readonly IAction[] | IActionProvider,
    contextMenuProvider: IContextMenuProvider,
    options: IDropdownMenuActionViewItemOptions = Object.create(null)
  ) {
    super(null, action, options);

    this.menuActionsOrProvider = menuActionsOrProvider;
    this.contextMenuProvider = contextMenuProvider;
    this.options = options;

    if (this.options.actionRunner) {
      this.actionRunner = this.options.actionRunner;
    }
  }

  override render(container: HTMLElement): void {
    this.actionItem = container;

    const labelRenderer: ILabelRenderer = (
      el: HTMLElement
    ): IDisposable | null => {
      this.element = append(el, $('a.action-label'));

      let classNames: string[] = [];

      if (typeof this.options.classNames === 'string') {
        classNames = this.options.classNames.split(/\s+/g).filter((s) => !!s);
      } else if (this.options.classNames) {
        classNames = this.options.classNames;
      }

      // todo@aeschli: remove codicon, should come through `this.options.classNames`
      if (!classNames.find((c) => c === 'icon')) {
        classNames.push('codicon');
      }

      this.element.classList.add(...classNames);

      this.element.setAttribute('role', 'button');
      this.element.setAttribute('aria-haspopup', 'true');
      this.element.setAttribute('aria-expanded', 'false');
      this.element.title = this._action.label || '';

      return null;
    };

    const isActionsArray = Array.isArray(this.menuActionsOrProvider);
    const options: IDropdownMenuOptions = {
      contextMenuProvider: this.contextMenuProvider,
      labelRenderer: labelRenderer,
      menuAsChild: this.options.menuAsChild,
      actions: isActionsArray
        ? (this.menuActionsOrProvider as IAction[])
        : undefined,
      actionProvider: isActionsArray
        ? undefined
        : (this.menuActionsOrProvider as IActionProvider),
    };

    this.dropdownMenu = this._register(new DropdownMenu(container, options));
    this._register(
      this.dropdownMenu.onDidChangeVisibility((visible) => {
        this.element?.setAttribute('aria-expanded', `${visible}`);
        this._onDidChangeVisibility.fire(visible);
      })
    );

    this.dropdownMenu.menuOptions = {
      actionViewItemProvider: this.options.actionViewItemProvider,
      actionRunner: this.actionRunner,
      getKeyBinding: this.options.keybindingProvider,
      context: this._context,
    };

    if (this.options.anchorAlignmentProvider) {
      const that = this;

      this.dropdownMenu.menuOptions = {
        ...this.dropdownMenu.menuOptions,
        get anchorAlignment(): AnchorAlignment {
          return that.options.anchorAlignmentProvider!();
        },
      };
    }

    this.updateEnabled();
  }

  override setActionContext(newContext: unknown): void {
    super.setActionContext(newContext);

    if (this.dropdownMenu) {
      if (this.dropdownMenu.menuOptions) {
        this.dropdownMenu.menuOptions.context = newContext;
      } else {
        this.dropdownMenu.menuOptions = { context: newContext };
      }
    }
  }

  protected override updateEnabled(): void {
    const disabled = !this.getAction().enabled;
    this.actionItem?.classList.toggle('disabled', disabled);
    this.element?.classList.toggle('disabled', disabled);
  }
}