avalon2/src/renders/share.js

an elegant efficient express mvvm framework

import { avalon, createFragment } from '../seed/core'
import { lookupOption, getSelectedValue } from '../directives/duplex/option'

function getChildren(arr) {
    var count = 0
    for (var i = 0, el; el = arr[i++];) {
        if (el.nodeName === '#document-fragment') {
            count += getChildren(el.children)
        } else {
            count += 1
        }
    }
    return count
}
export function groupTree(parent, children) {
    children && children.forEach(function (vdom) {
        if (!vdom)
            return
        var vlength = vdom.children && getChildren(vdom.children)
        if (vdom.nodeName === '#document-fragment') {
            var dom = createFragment()
        } else {
            dom = avalon.vdom(vdom, 'toDOM')
            var domlength = dom.childNodes && dom.childNodes.length
            if (domlength && vlength && domlength > vlength) {
                if (!appendChildMayThrowError[dom.nodeName]) {
                    avalon.clearHTML(dom)
                }
            }
        }
        if (vlength) {
            groupTree(dom, vdom.children)
            if (vdom.nodeName === 'select') {
                var values = []
                getSelectedValue(vdom, values)
                lookupOption(vdom, values)
            }
        }
        //高级版本可以尝试 querySelectorAll

        try {
            if (!appendChildMayThrowError[parent.nodeName]) {
                parent.appendChild(dom)
            }
        } catch (e) { }
    })
}

export function dumpTree(elem) {
    if (elem) {
        var firstChild
        while (firstChild = elem.firstChild) {
            if (firstChild.nodeType === 1) {
                dumpTree(firstChild)
            }
            elem.removeChild(firstChild)
        }
    }
}

export function getRange(childNodes, node) {
    var i = childNodes.indexOf(node) + 1
    var deep = 1,
        nodes = [],
        end
    nodes.start = i
    while (node = childNodes[i++]) {
        nodes.push(node)
        if (node.nodeName === '#comment') {
            if (startWith(node.nodeValue, 'ms-for:')) {
                deep++
            } else if (node.nodeValue === 'ms-for-end:') {
                deep--
                if (deep === 0) {
                    end = node
                    nodes.pop()
                    break
                }
            }
        }
    }
    nodes.end = end
    return nodes
}

export function startWith(long, short) {
    return long.indexOf(short) === 0
}

var appendChildMayThrowError = {
    '#text': 1,
    '#comment': 1,
    script: 1,
    style: 1,
    noscript: 1
}