class Container {
  // 容器配置
 private options: Options;
  // 容器节点
 private node: NodeInterface;
  // 是否 focus
 private _focused: boolean = false;
 #styleElement?: Element;

 constructor(selector: Selector, options: Options) {
  this.node = $(selector);
  this.options = options;
  this._init();
    // 初始化容器 focus
  this._focused =
   document.activeElement !== null &&
   this.node.equal(document.activeElement);
 }

 _init() {
  const { lang, tabIndex, className } = this.options;
    // 设置 container 的 data-element 元素类型为 root
  this.node.attributes(DATA_ELEMENT, ROOT);
    // 设置 container 的通用属性
  this.node.attributes({
   contenteditable: 'true',
   role: 'textbox',
   autocorrect: lang === 'en-US' ? 'on' : 'off',
   autocomplete: 'off',
   spellcheck: lang === 'en-US' ? 'true' : 'false',
   'data-gramm': 'false',
  });

  if (tabIndex !== undefined) {
   this.node.attributes('tabindex', tabIndex);
  }

  if (!this.node.hasClass('am-engine')) {
   this.node.addClass('am-engine');
  }

  if (isMobile) this.node.addClass('am-engine-mobile');

  // className 支持 array 和 string
    if (className !== undefined) {
   (Array.isArray(className)
    ? className
    : className.split(/\s+/)
   ).forEach((name) => {
    if (name.trim() !== '') this.node.addClass(name);
   });
  }
 }

 init() {
  const { engine } = this.options;
    // 监听 container 的 input 事件
  this.node.on('input', (e) => {
      // 预览模式不作处理
   if (engine.readonly) {
    return;
   }

   // card: card model instance
      // 不处理卡片中的输入事件
      if (engine.card.find(e.target)) {
    return;
   }
   const range = engine.change.range.get();
   range.handleBr(true);
  });
  // 编辑器文档尾部始终保持一行
  this.node.on('click', (event: MouseEvent) => {
   if (event.target && $(event.target).isEditable()) {
    // 获取到编辑器内最后一个子节点
    const block = this.node.last();
    if (block) {
     //不是卡片不处理
     if (!block.isCard()) return;
     //节点不可见不处理
     if (
      (block.get<HTMLElement>()?.offsetTop || 0) +
       (block.get<Element>()?.clientHeight || 0) >
      event.offsetY
     )
      return;
    }
    const node = $('<p><br /></p>');
    this.node.append(node);
    const range = engine.change.range.get();
        // 聚焦光标在最后一行
    range.select(node, true).collapse(false);
    engine.change.apply(range);
   }
  });
  let isMousedown = false;
  this.node.on(isMobile ? 'touchstart' : 'mousedown', () => {
   isMousedown = true;
   setTimeout(() => {
    if (!this._focused) {
     this._focused = true;
          // 鼠标按下触发 focus 事件
     engine.trigger('focus');
    }
    isMousedown = false;
   }, 10);
  });
  this.node.on('focus', () => {
   isMousedown = false;
   this._focused = true;
   engine.trigger('focus');
  });
  this.node.on('blur', () => {
   if (isMousedown) return;
   isMousedown = false;
   this._focused = false;
   engine.trigger('blur');
  });
 }

 isFocus() {
  return this._focused;
 }

 getNode() {
  return this.node;
 }

 setReadonly(readonly: boolean) {
  this.node.attributes('contenteditable', readonly ? 'false' : 'true');
 }

 showPlaceholder() {
  const { placeholder } = this.options;
  if (placeholder) {
   if (this.#styleElement && this.#styleElement.parentNode)
    document.body.removeChild(this.#styleElement);
   this.#styleElement = document.createElement('style');
   //const left = this.node.css('padding-left');
   //const top = this.node.css('padding-top');
      // 创建 placeholder 伪元素
   const styleText = document.createTextNode(`.am-engine:before {
                content: attr(data-placeholder);
                pointer-events: none;
                position: absolute;
                color: #bbbfc4;
                height: 0;
            }`);
   this.#styleElement.appendChild(styleText);
   document.body.appendChild(this.#styleElement);
   this.node.attributes({
    'data-placeholder': placeholder,
   });
  } else if (this.#styleElement && this.#styleElement.parentNode)
   document.body.removeChild(this.#styleElement);
 }

 hidePlaceholder() {
  this.node.removeAttributes('data-placeholder');
 }

 destroy() {
  const { className, engine } = this.options;
  this.node.removeAttributes(DATA_ELEMENT);
  this.node.removeAttributes('contenteditable');
  this.node.removeAttributes('role');
  this.node.removeAttributes('autocorrect');
  this.node.removeAttributes('autocomplete');
  this.node.removeAttributes('spellcheck');
  this.node.removeAttributes('data-gramm');
  this.node.removeAttributes('tabindex');
  this.node.removeAttributes('data-placeholder');
  if (this.#styleElement) document.body.removeChild(this.#styleElement);
  if (this.options.className) {
   (Array.isArray(className)
    ? className
    : (className || '').split(/\s+/)
   ).forEach((name) => {
    if (name.trim() !== '') this.node.removeClass(name);
   });
  }

  if (engine.card.closest(this.node)) this.node.removeClass('am-engine');
  this.node.removeAllEvents();
 }
}

export default Container;