// Copyright 2020 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import {Debouncer, DOM, V8CustomElement} from './helper.mjs';

DOM.defineCustomElement('view/tool-tip',
                        (templateText) =>
                            class Tooltip extends V8CustomElement {
  _targetNode;
  _content;
  _isHidden = true;
  _debouncedSetData = new Debouncer((...args) => this._setData(...args), 500)

  constructor() {
    super(templateText);
    this._intersectionObserver = new IntersectionObserver((entries) => {
      if (entries[0].intersectionRatio <= 0) {
        this.hide();
      } else {
        this.show();
        this.requestUpdate(true);
      }
    });
    document.addEventListener('click', (event) => {
      // Only hide the tooltip if we click anywhere outside of it.
      let target = event.target;
      while (target) {
        if (target == this) return;
        target = target.parentNode;
      }
      this.hide()
    });
  }

  _update() {
    if (!this._targetNode || this._isHidden) return;
    if (!this._targetNode.parentNode) return;
    const rect = this._targetNode.getBoundingClientRect();
    rect.x += rect.width / 2;
    let atRight = this._useRight(rect.x);
    let atBottom = this._useBottom(rect.y);
    if (atBottom) rect.y += rect.height;
    this._setPosition(rect, atRight, atBottom);
    this.requestUpdate(true);
  }

  set data({content, positionOrTargetNode, immediate}) {
    if (immediate) {
      this._debouncedSetData.callNow(content, positionOrTargetNode)
    } else {
      this._debouncedSetData.call(content, positionOrTargetNode)
    }
  }

  _setData(content, positionOrTargetNode) {
    if (positionOrTargetNode.nodeType === undefined) {
      this._targetNode = undefined;
      const position = positionOrTargetNode;
      this._setPosition(
          position, this._useRight(position.x), this._useBottom(position.y));
    } else {
      this._setTargetNode(positionOrTargetNode);
    }
    this._setContent(content);
  }

  _setTargetNode(targetNode) {
    this._intersectionObserver.disconnect();
    this._targetNode = targetNode;
    if (targetNode === undefined) return;
    if (!(targetNode instanceof SVGElement)) {
      this._intersectionObserver.observe(targetNode);
    }
    this.requestUpdate(true);
  }

  _setPosition(viewportPosition, atRight, atBottom) {
    const horizontalMode = atRight ? 'right' : 'left';
    const verticalMode = atBottom ? 'bottom' : 'top';
    this.bodyNode.className = horizontalMode + ' ' + verticalMode;
    const pageX = viewportPosition.x + window.scrollX;
    this.style.left = `${pageX}px`;
    const pageY = viewportPosition.y + window.scrollY;
    this.style.top = `${pageY}px`;
  }

  _useBottom(viewportY) {
    return viewportY <= 400;
  }

  _useRight(viewportX) {
    return viewportX < document.documentElement.clientWidth / 2;
  }

  _setContent(content) {
    if (!content) return this.hide();
    this.show();
    if (this._content === content) return;
    this._content = content;

    if (typeof content === 'string') {
      this.contentNode.innerHTML = content;
      this.contentNode.className = 'textContent';
    } else if (content?.nodeType && content?.nodeName) {
      this._setContentNode(content);
    } else {
      if (this.contentNode.firstChild?.localName == 'property-link-table') {
        this.contentNode.firstChild.propertyDict = content;
      } else {
        const node = DOM.element('property-link-table');
        node.instanceLinkButtons = true;
        node.propertyDict = content;
        this._setContentNode(node);
      }
    }
  }

  _setContentNode(content) {
    const newContent = DOM.div();
    newContent.appendChild(content);
    this.contentNode.replaceWith(newContent);
    newContent.id = 'content';
  }

  hide() {
    this._content = undefined;
    if (this._isHidden) return;
    this._isHidden = true;
    this.bodyNode.style.display = 'none';
    this.targetNode = undefined;
  }

  show() {
    if (!this._isHidden) return;
    this.bodyNode.style.display = 'block';
    this._isHidden = false;
  }

  get bodyNode() {
    return this.$('#body');
  }

  get contentNode() {
    return this.$('#content');
  }
});