// Array[Object], ance: 当前children列表. 
let parentList = []
let List = [] // Array[Object], ance: 当前children列表. current: 当前子元素遍历下标. 遍历方式从深处开始遍历,"树"的数据结构
function writeText(item, childArr=[], childIndex, parent=document.querySelector('.text-wrap')) {
    let data = {}
    if(childArr.length > 0){
        data = childArr[childIndex]
    }else {
        data = item
    }
    let num = 0;
    let text = data.text ? data.text : ''
    let dom = document.createElement(data.name)
    dom.setAttribute('class', data.class || '')
    parent.appendChild(dom)
    let timer = setInterval(() => {
        if(num <= text.length){
            dom.innerHTML = text.substr(0, num)
            resume.scrollTop = 100000
            num++
        }else{
            clearInterval(timer)
            if (data.children) {
                List.push({
                    ance: data.children,
                    current: 0,
                    length: data.children.length
                })
                parentList.push(dom)
                writeText('', data.children, 0, dom)
            }else if (childArr.length > 0) {
                if(childArr.length-1 > childIndex){
                    writeText('', childArr, ++childIndex, parentList[parentList.length-1])
                    List[List.length-1].current = List[List.length-1].current + 1
                }else {
                    parentList.pop()
                    filterLength()
                }
            }else if (textArr.length-1 > currentIndex_) { // 
                writeText(textArr[++currentIndex_])
                parentList = []
            }
        }
    }, 20);
}
function filterLength () {
    for (let i = List.length-1; i >=0; i--) {
        if(List[i].length-1 == List[i].current){
            List.pop()
        }else{
            List[List.length-1].current = List[List.length-1].current + 1
            break;
        }
    }
    if(List.length>0){
        writeText('', List[List.length-1].ance, List[List.length-1].current,parentList[parentList.length-1])
    }else if(textArr.length-1 > currentIndex_){
        writeText(textArr[++currentIndex_])
        parentList = []
    }
}