class ChainQueue {
 constructor(items) {
  this.items = items || []
  this.maxNum = 200
 }
}

// 添加数组队列
entryArrQueue(node) {
 Array.isArray(node)
 node.map(item => this.items.push(item))
}

// 添加队列
entryQueue(node) {
 if (this.items.length > this.maxNum) {
  return
 }
 if (Array.isArray(node)) {
  node.map(item => this.items.push(item))
 } else {
  this.items.push(node)
 }
}

deleteQueue(func = () => {}) {
 assert(isFunc(func), `${func} is not function`)
 func(this.items.shift())
}

front() {
 return this.items[0]
}

clear() {
 this.items = []
}

const isFunc = v => typeof v === 'function'
const assert = (condition, msg) => {
 if (!condition) throw new Error(`[dashboard]${msg}`)
}
class ChainQueue {
 constructor(items) {
  this.items = items || []
  this.maxNum = 200
 }

 // 添加数组队列
 entryArrQueue(node) {
  Array.isArray(node)
  node.map(item => this.items.push(item))
 }

 // 添加队列
 entryQueue(node) {
  if (this.items.length > this.maxNum) {
   return
  }
  if (Array.isArray(node)) {
   node.map(item => this.items.push(item))
  } else {
   this.items.push(node)
  }
 }

 // 删除队列，返回删除的当前的项目
 deleteQueue(func = () => {}) {
  assert(isFunc(func), `${func} is not function`)
  func(this.items.shift())
 }

 // 返回队列的第一个
 front() {
  return this.items[0]
 }

 // 清除队列
 clear() {
  this.items = []
 }
 get size() {
  return this.items.length
 }

 get isEmpty() {
  return !this.items.length
 }

 print() {
  console.log(this.items.toString())
  console.log(this.items)
 }
 result() {
  return this.items
 }
}

module.exports = ChainQueue

// export default ChainQueue
// export default (ChainQueue = new ChainQueue())