/*---------------------------------------------------------------------------------------------
 *  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!./overlayWidgets';
import {
  FastDomNode,
  createFastDomNode,
} from '../../../../../vs/base/browser/fastDomNode';
import {
  IOverlayWidget,
  OverlayWidgetPositionPreference,
} from '../../../../../vs/editor/browser/editorBrowser';
import {
  PartFingerprint,
  PartFingerprints,
  ViewPart,
} from '../../../../../vs/editor/browser/view/viewPart';
import {
  RenderingContext,
  RestrictedRenderingContext,
} from '../../../../../vs/editor/common/view/renderingContext';
import { ViewContext } from '../../../../../vs/editor/common/view/viewContext';
import * as viewEvents from '../../../../../vs/editor/common/view/viewEvents';
import { EditorOption } from '../../../../../vs/editor/common/config/editorOptions';

interface IWidgetData {
  widget: IOverlayWidget;
  preference: OverlayWidgetPositionPreference | null;
  domNode: FastDomNode<HTMLElement>;
}

interface IWidgetMap {
  [key: string]: IWidgetData;
}

export class ViewOverlayWidgets extends ViewPart {
  private _widgets: IWidgetMap;
  private readonly _domNode: FastDomNode<HTMLElement>;

  private _verticalScrollbarWidth: number;
  private _minimapWidth: number;
  private _horizontalScrollbarHeight: number;
  private _editorHeight: number;
  private _editorWidth: number;

  constructor(context: ViewContext) {
    super(context);

    const options = this._context.configuration.options;
    const layoutInfo = options.get(EditorOption.layoutInfo);

    this._widgets = {};
    this._verticalScrollbarWidth = layoutInfo.verticalScrollbarWidth;
    this._minimapWidth = layoutInfo.minimap.minimapWidth;
    this._horizontalScrollbarHeight = layoutInfo.horizontalScrollbarHeight;
    this._editorHeight = layoutInfo.height;
    this._editorWidth = layoutInfo.width;

    this._domNode = createFastDomNode(document.createElement('div'));
    PartFingerprints.write(this._domNode, PartFingerprint.OverlayWidgets);
    this._domNode.setClassName('overlayWidgets');
  }

  public override dispose(): void {
    super.dispose();
    this._widgets = {};
  }

  public getDomNode(): FastDomNode<HTMLElement> {
    return this._domNode;
  }

  // ---- begin view event handlers

  public override onConfigurationChanged(
    e: viewEvents.ViewConfigurationChangedEvent
  ): boolean {
    const options = this._context.configuration.options;
    const layoutInfo = options.get(EditorOption.layoutInfo);

    this._verticalScrollbarWidth = layoutInfo.verticalScrollbarWidth;
    this._minimapWidth = layoutInfo.minimap.minimapWidth;
    this._horizontalScrollbarHeight = layoutInfo.horizontalScrollbarHeight;
    this._editorHeight = layoutInfo.height;
    this._editorWidth = layoutInfo.width;
    return true;
  }

  // ---- end view event handlers

  public addWidget(widget: IOverlayWidget): void {
    const domNode = createFastDomNode(widget.getDomNode());

    this._widgets[widget.getId()] = {
      widget: widget,
      preference: null,
      domNode: domNode,
    };

    // This is sync because a widget wants to be in the dom
    domNode.setPosition('absolute');
    domNode.setAttribute('widgetId', widget.getId());
    this._domNode.appendChild(domNode);

    this.setShouldRender();
  }

  public setWidgetPosition(
    widget: IOverlayWidget,
    preference: OverlayWidgetPositionPreference | null
  ): boolean {
    const widgetData = this._widgets[widget.getId()];
    if (widgetData.preference === preference) {
      return false;
    }

    widgetData.preference = preference;
    this.setShouldRender();

    return true;
  }

  public removeWidget(widget: IOverlayWidget): void {
    const widgetId = widget.getId();
    if (this._widgets.hasOwnProperty(widgetId)) {
      const widgetData = this._widgets[widgetId];
      const domNode = widgetData.domNode.domNode;
      delete this._widgets[widgetId];

      domNode.parentNode!.removeChild(domNode);
      this.setShouldRender();
    }
  }

  private _renderWidget(widgetData: IWidgetData): void {
    const domNode = widgetData.domNode;

    if (widgetData.preference === null) {
      domNode.unsetTop();
      return;
    }

    if (
      widgetData.preference === OverlayWidgetPositionPreference.TOP_RIGHT_CORNER
    ) {
      domNode.setTop(0);
      domNode.setRight(2 * this._verticalScrollbarWidth + this._minimapWidth);
    } else if (
      widgetData.preference ===
      OverlayWidgetPositionPreference.BOTTOM_RIGHT_CORNER
    ) {
      const widgetHeight = domNode.domNode.clientHeight;
      domNode.setTop(
        this._editorHeight - widgetHeight - 2 * this._horizontalScrollbarHeight
      );
      domNode.setRight(2 * this._verticalScrollbarWidth + this._minimapWidth);
    } else if (
      widgetData.preference === OverlayWidgetPositionPreference.TOP_CENTER
    ) {
      domNode.setTop(0);
      domNode.domNode.style.right = '50%';
    }
  }

  public prepareRender(ctx: RenderingContext): void {
    // Nothing to read
  }

  public render(ctx: RestrictedRenderingContext): void {
    this._domNode.setWidth(this._editorWidth);

    const keys = Object.keys(this._widgets);
    for (let i = 0, len = keys.length; i < len; i++) {
      const widgetId = keys[i];
      this._renderWidget(this._widgets[widgetId]);
    }
  }
}