class BaseElement {
  constructor(elementType = 'div', engineId) {
    this.element = document.createElement(elementType)
    this.element.style.position = 'absolute'
    this.engineId = engineId
    this.x = 0
    this.y = 0
    this.width = 0
    this.height = 0
  }

  setPosition(x = 0, y = 0) {
    this.element.style.left = `${x}px`
    this.element.style.top = `${y}px`
    this.x = x
    this.y = y
  }

  setSize(width = 0, height = 0) {
    if (width) {
      this.element.style.width = typeof width === 'number' ? `${width}px` : width
      this.width = width
    }
    if (height) {
      this.element.style.height = typeof height === 'number' ? `${height}px` : height
      this.height = height
    }
  }

  setStyle(style) {
    Object.assign(this.element.style, style)
  }

  add(child) {
    child && this.element.appendChild(child.element || child)
  }

  remove(child) {
    child && this.element.removeChild(child.element || child)
  }

  on(event, callback) {
    this.element.addEventListener(event, callback)
  }

  off(event, callback) {
    this.element.removeEventListener(event, callback)
  }

  hide() {
    this.element.style.display = 'none'
  }

  show() {
    this.element.style.display = 'block'
  }
}

class Sprite extends BaseElement {
  constructor(img, x, y, width, height, engineId) {
    super('div', engineId)
    this.imgElement = document.createElement('img')
    this.imgElement.src = img.src
    this.imgElement.style.cssText = '-webkit-user-drag: none; user-drag: none;'
    this.element.appendChild(this.imgElement)

    this.setPosition(x, y)
    this.setSize(width, height)
    this.element.setAttribute('data-sprite-id', engineId)

    // 精灵特有方法
    this.name = name => this.element.setAttribute('data-name', name)
    this.animate = keyframes => (this.element.style.animation = keyframes)
  }
}

class Box extends BaseElement {
  constructor(x, y, width, height, engineId) {
    super('div', engineId)
    this.setPosition(x, y)
    this.setSize(width, height)
    this.element.setAttribute('data-box-id', engineId)
  }
}

class TextElement extends BaseElement {
  constructor(text, x, y, engineId) {
    super('div', engineId)
    this.element.innerText = text
    this.setPosition(x, y)
    this.element.setAttribute('data-text-id', engineId)

    // 文本特有方法
    this.set = text => (this.element.innerText = text)
    this.setColor = color => (this.element.style.color = color)
    this.setFont = font => (this.element.style.font = font)
  }
}

class HtmlElement extends BaseElement {
  constructor(html, x, y, engineId) {
    super('div', engineId)
    this.element.innerHTML = html
    this.setPosition(x, y)
    this.element.setAttribute('data-html-id', engineId)

    // HTML特有方法
    this.set = html => (this.element.innerHTML = html)
    this.get = () => this.element.innerHTML
    this.getSize = () => {
      const rect = this.element.getBoundingClientRect()
      return { width: rect.width, height: rect.height }
    }
  }
}

class SvgElement extends BaseElement {
  constructor(x, y, width, height, content, engineId) {
    super('div', engineId)
    this.element.innerHTML = content
    this.setPosition(x, y)
    this.setSize(width, height)
    this.element.setAttribute('data-svg-id', engineId)

    // SVG特有方法
    this.setContent = content => (this.element.innerHTML = content)
  }
}

class Engine {
  constructor(element = document.body, options = {}) {
    const defaultOptions = {
      width: 800,
      height: 600,
      background: 'transparent',
    }

    this.options = { ...defaultOptions, ...options }
    this.images = []
    this.width = this.options.width
    this.height = this.options.height
    this.element = typeof element === 'string' ? document.querySelector(element) : element
    this.id = Date.now().toString(16)

    this.createStage()
  }

  createStage() {
    this.stage = document.createElement('div')
    this.stage.setAttribute('data-engine-id', this.id)

    Object.assign(this.stage.style, {
      width: `${this.options.width}px`,
      height: `${this.options.height}px`,
      position: 'relative',
      userSelect: 'none',
      overflow: 'hidden',
      background: this.options.background,
      transform: 'translateZ(0)',
    })

    // 添加舞台操作方法
    this.stage.add = child => child && this.stage.appendChild(child.element || child)
    this.stage.remove = child => child && this.stage.removeChild(child.element || child)

    this.element.appendChild(this.stage)
  }

  load(src = '') {
    return new Promise((resolve, reject) => {
      const img = new Image()
      img.src = src
      img.onload = () => resolve(img)
      img.onerror = reject
      this.images.push(img)
    })
  }

  createSprite(img, x = 0, y = 0, width = 0, height = 0) {
    return new Sprite(img, x, y, width, height, this.id)
  }

  createBox(x = 0, y = 0, width = 0, height = 0) {
    return new Box(x, y, width, height, this.id)
  }

  createText(text = '', x = 0, y = 0) {
    return new TextElement(text, x, y, this.id)
  }

  createHtml(html = '', x = 0, y = 0) {
    return new HtmlElement(html, x, y, this.id)
  }

  createSvg(x = 0, y = 0, width = 0, height = 0, content = '') {
    return new SvgElement(x, y, width, height, content, this.id)
  }

  destroy() {
    if (this.stage && this.stage.parentNode) {
      this.stage.parentNode.removeChild(this.stage)
    }

    // 清理所有图像引用
    this.images.forEach(img => {
      img.onload = null
      img.onerror = null
      img.src = ''
    })

    // 清除所有引用
    this.images = []
    this.stage = null
    this.element = null
    this.options = null
  }
}