(function() { "use strict"; var diffcount; var Diff = function (options) { var diff = this; Object.keys(options).forEach(function(option) { diff[option] = options[option]; }); }; Diff.prototype = { toString: function() { return JSON.stringify(this); } // TODO: compress diff output by replacing these keys with numbers or alike: /* 'addAttribute' = 0, 'modifyAttribute' = 1, 'removeAttribute' = 2, 'modifyTextElement' = 3, 'relocateGroup' = 4, 'removeElement' = 5, 'addElement' = 6, 'removeTextElement' = 7, 'addTextElement' = 8, 'replaceElement' = 9, 'modifyValue' = 10, 'modifyChecked' = 11, 'modifySelected' = 12, 'modifyComment' = 13, 'action' = 14, 'route' = 15, 'oldValue' = 16, 'newValue' = 17, 'element' = 18, 'group' = 19, 'from' = 20, 'to' = 21, 'name' = 22, 'value' = 23, 'data' = 24, 'attributes' = 25, 'nodeName' = 26, 'childNodes' = 27, 'checked' = 28, 'selected' = 29;*/ }; var SubsetMapping = function SubsetMapping(a, b) { this.oldValue = a; this.newValue = b; }; SubsetMapping.prototype = { contains: function contains(subset) { if (subset.length < this.length) { return subset.newValue >= this.newValue && subset.newValue < this.newValue + this.length; } return false; }, toString: function toString() { return this.length + " element subset, first mapping: old " + this.oldValue + " → new " + this.newValue; } }; var elementDescriptors = function(el) { var output = []; if (el.nodeName !== '#text' && el.nodeName !== '#comment') { output.push(el.nodeName); if (el.attributes) { if (el.attributes['class']) { output.push(el.nodeName + '.' + el.attributes['class'].replace(/ /g, '.')); } if (el.attributes.id) { output.push(el.nodeName + '#' + el.attributes.id); } } } return output; }; var findUniqueDescriptors = function(li) { var uniqueDescriptors = {}, duplicateDescriptors = {}; li.forEach(function(node) { elementDescriptors(node).forEach(function(descriptor) { var inUnique = descriptor in uniqueDescriptors, inDupes = descriptor in duplicateDescriptors; if (!inUnique && !inDupes) { uniqueDescriptors[descriptor] = true; } else if (inUnique) { delete uniqueDescriptors[descriptor]; duplicateDescriptors[descriptor] = true; } }); }); return uniqueDescriptors; }; var uniqueInBoth = function(l1, l2) { var l1Unique = findUniqueDescriptors(l1), l2Unique = findUniqueDescriptors(l2), inBoth = {}; Object.keys(l1Unique).forEach(function(key) { if (l2Unique[key]) { inBoth[key] = true; } }); return inBoth; }; var removeDone = function(tree) { delete tree.outerDone; delete tree.innerDone; delete tree.valueDone; if (tree.childNodes) { return tree.childNodes.every(removeDone); } else { return true; } }; var isEqual = function(e1, e2) { var e1Attributes, e2Attributes; if (!['nodeName', 'value', 'checked', 'selected', 'data'].every(function(element) { if (e1[element] !== e2[element]) { return false; } return true; })) { return false; } if (Boolean(e1.attributes) !== Boolean(e2.attributes)) { return false; } if (Boolean(e1.childNodes) !== Boolean(e2.childNodes)) { return false; } if (e1.attributes) { e1Attributes = Object.keys(e1.attributes); e2Attributes = Object.keys(e2.attributes); if (e1Attributes.length !== e2Attributes.length) { return false; } if (!e1Attributes.every(function(attribute) { if (e1.attributes[attribute] !== e2.attributes[attribute]) { return false; } })) { return false; } } if (e1.childNodes) { if (e1.childNodes.length !== e2.childNodes.length) { return false; } if (!e1.childNodes.every(function(childNode, index) { return isEqual(childNode, e2.childNodes[index]); })) { return false; } } return true; }; var roughlyEqual = function(e1, e2, uniqueDescriptors, sameSiblings, preventRecursion) { var childUniqueDescriptors, nodeList1, nodeList2; if (!e1 || !e2) { return false; } if (e1.nodeName !== e2.nodeName) { return false; } if (e1.nodeName === '#text') { // Note that we initially don't care what the text content of a node is, // the mere fact that it's the same tag and "has text" means it's roughly // equal, and then we can find out the true text difference later. return preventRecursion ? true : e1.data === e2.data; } if (e1.nodeName in uniqueDescriptors) { return true; } if (e1.attributes && e2.attributes) { if (e1.attributes.id && e1.attributes.id === e2.attributes.id) { var idDescriptor = e1.nodeName + '#' + e1.attributes.id; if (idDescriptor in uniqueDescriptors) { return true; } } if (e1.attributes['class'] && e1.attributes['class'] === e2.attributes['class']) { var classDescriptor = e1.nodeName + '.' + e1.attributes['class'].replace(/ /g, '.'); if (classDescriptor in uniqueDescriptors) { return true; } } } if (sameSiblings) { return true; } nodeList1 = e1.childNodes ? e1.childNodes.slice().reverse() : []; nodeList2 = e2.childNodes ? e2.childNodes.slice().reverse() : []; if (nodeList1.length !== nodeList2.length) { return false; } if (preventRecursion) { return nodeList1.every(function(element, index) { return element.nodeName === nodeList2[index].nodeName; }); } else { // note: we only allow one level of recursion at any depth. If 'preventRecursion' // was not set, we must explicitly force it to true for child iterations. childUniqueDescriptors = uniqueInBoth(nodeList1, nodeList2); return nodeList1.every(function(element, index) { return roughlyEqual(element, nodeList2[index], childUniqueDescriptors, true, true); }); } }; var cloneObj = function(obj) { // TODO: Do we really need to clone here? Is it not enough to just return the original object? return JSON.parse(JSON.stringify(obj)); //return obj; }; /** * based on https://en.wikibooks.org/wiki/Algorithm_implementation/Strings/Longest_common_substring#JavaScript */ var findCommonSubsets = function(c1, c2, marked1, marked2) { var lcsSize = 0, index = [], matches = Array.apply(null, new Array(c1.length + 1)).map(function() { return []; }), // set up the matching table uniqueDescriptors = uniqueInBoth(c1, c2), // If all of the elements are the same tag, id and class, then we can // consider them roughly the same even if they have a different number of // children. This will reduce removing and re-adding similar elements. subsetsSame = c1.length === c2.length, origin, ret; if (subsetsSame) { c1.some(function(element, i) { var c1Desc = elementDescriptors(element), c2Desc = elementDescriptors(c2[i]); if (c1Desc.length !== c2Desc.length) { subsetsSame = false; return true; } c1Desc.some(function(description, i) { if (description !== c2Desc[i]) { subsetsSame = false; return true; } }); if (!subsetsSame) { return true; } }); } // fill the matches with distance values c1.forEach(function(c1Element, c1Index) { c2.forEach(function(c2Element, c2Index) { if (!marked1[c1Index] && !marked2[c2Index] && roughlyEqual(c1Element, c2Element, uniqueDescriptors, subsetsSame)) { matches[c1Index + 1][c2Index + 1] = (matches[c1Index][c2Index] ? matches[c1Index][c2Index] + 1 : 1); if (matches[c1Index + 1][c2Index + 1] >= lcsSize) { lcsSize = matches[c1Index + 1][c2Index + 1]; index = [c1Index + 1, c2Index + 1]; } } else { matches[c1Index + 1][c2Index + 1] = 0; } }); }); if (lcsSize === 0) { return false; } origin = [index[0] - lcsSize, index[1] - lcsSize]; ret = new SubsetMapping(origin[0], origin[1]); ret.length = lcsSize; return ret; }; /** * This should really be a predefined function in Array... */ var makeArray = function(n, v) { return Array.apply(null, new Array(n)).map(function() { return v; }); }; /** * Generate arrays that indicate which node belongs to which subset, * or whether it's actually an orphan node, existing in only one * of the two trees, rather than somewhere in both. * * So if t1 =
, t2 =
. * The longest subset is "
" (length 2), so it will group 0. * The second longest is "" (length 1), so it will be group 1. * gaps1 will therefore be [1,0,0] and gaps2 [0,0,1]. * * If an element is not part of any group, it will stay being 'true', which * is the initial value. For example: * t1 =


, t2 =
* * The "

" and "" do only show up in one of the two and will * therefore be marked by "true". The remaining parts are parts of the * groups 0 and 1: * gaps1 = [1, true, 0, 0], gaps2 = [true, 0, 0, 1] * */ var getGapInformation = function(t1, t2, stable) { var gaps1 = t1.childNodes ? makeArray(t1.childNodes.length, true) : [], gaps2 = t2.childNodes ? makeArray(t2.childNodes.length, true) : [], group = 0; // give elements from the same subset the same group number stable.forEach(function(subset) { var i, endOld = subset.oldValue + subset.length, endNew = subset.newValue + subset.length; for (i = subset.oldValue; i < endOld; i += 1) { gaps1[i] = group; } for (i = subset.newValue; i < endNew; i += 1) { gaps2[i] = group; } group += 1; }); return { gaps1: gaps1, gaps2: gaps2 }; }; /** * Find all matching subsets, based on immediate child differences only. */ var markSubTrees = function(oldTree, newTree) { // note: the child lists are views, and so update as we update old/newTree var oldChildren = oldTree.childNodes ? oldTree.childNodes : [], newChildren = newTree.childNodes ? newTree.childNodes : [], marked1 = makeArray(oldChildren.length, false), marked2 = makeArray(newChildren.length, false), subsets = [], subset = true, returnIndex = function() { return arguments[1]; }, markBoth = function(i) { marked1[subset.oldValue + i] = true; marked2[subset.newValue + i] = true; }; while (subset) { subset = findCommonSubsets(oldChildren, newChildren, marked1, marked2); if (subset) { subsets.push(subset); Array.apply(null, new Array(subset.length)).map(returnIndex).forEach(markBoth); } } return subsets; }; function swap(obj, p1, p2) { (function(_) { obj[p1] = obj[p2]; obj[p2] = _; }(obj[p1])); } var DiffTracker = function() { this.list = []; }; DiffTracker.prototype = { list: false, add: function(diffs) { var list = this.list; diffs.forEach(function(diff) { list.push(diff); }); }, forEach: function(fn) { this.list.forEach(fn); } }; var diffDOM = function(options) { var defaults = { debug: false, diffcap: 10, // Limit for how many diffs are accepting when debugging. Inactive when debug is false. maxDepth: false, // False or a numeral. If set to a numeral, limits the level of depth that the the diff mechanism looks for differences. If false, goes through the entire tree. valueDiffing: true, // Whether to take into consideration the values of forms that differ from auto assigned values (when a user fills out a form). // syntax: textDiff: function (node, currentValue, expectedValue, newValue) textDiff: function() { arguments[0].data = arguments[3]; return; }, // empty functions were benchmarked as running faster than both // `f && f()` and `if (f) { f(); }` preVirtualDiffApply: function () {}, postVirtualDiffApply: function () {}, preDiffApply: function () {}, postDiffApply: function () {}, filterOuterDiff: null }, i; if (typeof options === "undefined") { options = {}; } for (i in defaults) { if (typeof options[i] === "undefined") { this[i] = defaults[i]; } else { this[i] = options[i]; } } }; diffDOM.Diff = Diff; diffDOM.prototype = { // ===== Create a diff ===== diff: function(t1Node, t2Node) { var t1 = this.nodeToObj(t1Node), t2 = this.nodeToObj(t2Node); diffcount = 0; if (this.debug) { this.t1Orig = this.nodeToObj(t1Node); this.t2Orig = this.nodeToObj(t2Node); } this.tracker = new DiffTracker(); return this.findDiffs(t1, t2); }, findDiffs: function(t1, t2) { var diffs; do { if (this.debug) { diffcount += 1; if (diffcount > this.diffcap) { window.diffError = [this.t1Orig, this.t2Orig]; throw new Error("surpassed diffcap:" + JSON.stringify(this.t1Orig) + " -> " + JSON.stringify(this.t2Orig)); } } diffs = this.findNextDiff(t1, t2, []); if (diffs.length === 0) { // Last check if the elements really are the same now. // If not, remove all info about being done and start over. // Somtimes a node can be marked as done, but the creation of subsequent diffs means that it has to be changed anyway. if (!isEqual(t1, t2)) { removeDone(t1); diffs = this.findNextDiff(t1, t2, []); } } if (diffs.length > 0) { this.tracker.add(diffs); this.applyVirtual(t1, diffs); } } while (diffs.length > 0); return this.tracker.list; }, findNextDiff: function(t1, t2, route) { var diffs, fdiffs; if (this.maxDepth && route.length > this.maxDepth) { return []; } // outer differences? if (!t1.outerDone) { diffs = this.findOuterDiff(t1, t2, route); if (this.filterOuterDiff) { fdiffs = this.filterOuterDiff(t1, t2, diffs); if (fdiffs) diffs = fdiffs; } if (diffs.length > 0) { t1.outerDone = true; return diffs; } else { t1.outerDone = true; } } // inner differences? if (!t1.innerDone) { diffs = this.findInnerDiff(t1, t2, route); if (diffs.length > 0) { return diffs; } else { t1.innerDone = true; } } if (this.valueDiffing && !t1.valueDone) { // value differences? diffs = this.findValueDiff(t1, t2, route); if (diffs.length > 0) { t1.valueDone = true; return diffs; } else { t1.valueDone = true; } } // no differences return []; }, findOuterDiff: function(t1, t2, route) { var diffs = [], attr1, attr2; if (t1.nodeName !== t2.nodeName) { return [new Diff({ action: 'replaceElement', oldValue: cloneObj(t1), newValue: cloneObj(t2), route: route })]; } if (t1.data !== t2.data) { // Comment or text node. if (t1.nodeName === '#text') { return [new Diff({ action: 'modifyTextElement', route: route, oldValue: t1.data, newValue: t2.data })]; } else { return [new Diff({ action: 'modifyComment', route: route, oldValue: t1.data, newValue: t2.data })]; } } attr1 = t1.attributes ? Object.keys(t1.attributes).sort() : []; attr2 = t2.attributes ? Object.keys(t2.attributes).sort() : []; attr1.forEach(function(attr) { var pos = attr2.indexOf(attr); if (pos === -1) { diffs.push(new Diff({ action: 'removeAttribute', route: route, name: attr, value: t1.attributes[attr] })); } else { attr2.splice(pos, 1); if (t1.attributes[attr] !== t2.attributes[attr]) { diffs.push(new Diff({ action: 'modifyAttribute', route: route, name: attr, oldValue: t1.attributes[attr], newValue: t2.attributes[attr] })); } } }); attr2.forEach(function(attr) { diffs.push(new Diff({ action: 'addAttribute', route: route, name: attr, value: t2.attributes[attr] })); }); return diffs; }, nodeToObj: function(node) { var objNode = {}, dobj = this; objNode.nodeName = node.nodeName; if (objNode.nodeName === '#text' || objNode.nodeName === '#comment') { objNode.data = node.data; } else { if (node.attributes && node.attributes.length > 0) { objNode.attributes = {}; Array.prototype.slice.call(node.attributes).forEach( function(attribute) { objNode.attributes[attribute.name] = attribute.value; } ); } if (node.childNodes && node.childNodes.length > 0) { objNode.childNodes = []; Array.prototype.slice.call(node.childNodes).forEach( function(childNode) { objNode.childNodes.push(dobj.nodeToObj(childNode)); } ); } if (this.valueDiffing) { if (node.value !== undefined) { objNode.value = node.value; } if (node.checked !== undefined) { objNode.checked = node.checked; } if (node.selected !== undefined) { objNode.selected = node.selected; } } } return objNode; }, objToNode: function(objNode, insideSvg) { var node, dobj = this; if (objNode.nodeName === '#text') { node = document.createTextNode(objNode.data); } else if (objNode.nodeName === '#comment') { node = document.createComment(objNode.data); } else { if (objNode.nodeName === 'svg' || insideSvg) { node = document.createElementNS('http://www.w3.org/2000/svg', objNode.nodeName); insideSvg = true; } else { node = document.createElement(objNode.nodeName); } if (objNode.attributes) { Object.keys(objNode.attributes).forEach(function(attribute) { try { node.setAttribute(attribute, objNode.attributes[attribute]); } catch (e) { console.debug(e); } }); } if (objNode.childNodes) { objNode.childNodes.forEach(function(childNode) { try { node.appendChild(dobj.objToNode(childNode, insideSvg)); } catch (e) { console.debug(e); } }); } if (this.valueDiffing) { if (objNode.value) { node.value = objNode.value; } if (objNode.checked) { node.checked = objNode.checked; } if (objNode.selected) { node.selected = objNode.selected; } } } return node; }, findInnerDiff: function(t1, t2, route) { var subtrees = (t1.childNodes && t2.childNodes) ? markSubTrees(t1, t2) : [], t1ChildNodes = t1.childNodes ? t1.childNodes : [], t2ChildNodes = t2.childNodes ? t2.childNodes : [], childNodesLengthDifference, diffs = [], index = 0, last, e1, e2, i; if (subtrees.length > 0) { /* One or more groups have been identified among the childnodes of t1 * and t2. */ diffs = this.attemptGroupRelocation(t1, t2, subtrees, route); if (diffs.length > 0) { return diffs; } } /* 0 or 1 groups of similar child nodes have been found * for t1 and t2. 1 If there is 1, it could be a sign that the * contents are the same. When the number of groups is below 2, * t1 and t2 are made to have the same length and each of the * pairs of child nodes are diffed. */ last = Math.max(t1ChildNodes.length, t2ChildNodes.length); if (t1ChildNodes.length !== t2ChildNodes.length) { childNodesLengthDifference = true; } for (i = 0; i < last; i += 1) { e1 = t1ChildNodes[i]; e2 = t2ChildNodes[i]; if (childNodesLengthDifference) { /* t1 and t2 have different amounts of childNodes. Add * and remove as necessary to obtain the same length */ if (e1 && !e2) { if (e1.nodeName === '#text') { diffs.push(new Diff({ action: 'removeTextElement', route: route.concat(index), value: e1.data })); index -= 1; } else { diffs.push(new Diff({ action: 'removeElement', route: route.concat(index), element: cloneObj(e1) })); index -= 1; } } else if (e2 && !e1) { if (e2.nodeName === '#text') { diffs.push(new Diff({ action: 'addTextElement', route: route.concat(i), value: e2.data })); } else { diffs.push(new Diff({ action: 'addElement', route: route.concat(i), element: cloneObj(e2) })); } } } /* We are now guaranteed that childNodes e1 and e2 exist, * and that they can be diffed. */ /* Diffs in child nodes should not affect the parent node, * so we let these diffs be submitted together with other * diffs. */ if (e1 && e2) { diffs = diffs.concat(this.findNextDiff(e1, e2, route.concat(index))); } index += 1; } t1.innerDone = true; return diffs; }, attemptGroupRelocation: function(t1, t2, subtrees, route) { /* Either t1.childNodes and t2.childNodes have the same length, or * there are at least two groups of similar elements can be found. * attempts are made at equalizing t1 with t2. First all initial * elements with no group affiliation (gaps=true) are removed (if * only in t1) or added (if only in t2). Then the creation of a group * relocation diff is attempted. */ var gapInformation = getGapInformation(t1, t2, subtrees), gaps1 = gapInformation.gaps1, gaps2 = gapInformation.gaps2, shortest = Math.min(gaps1.length, gaps2.length), destinationDifferent, toGroup, group, node, similarNode, testI, diffs = [], index1, index2, j; for (index2 = 0, index1 = 0; index2 < shortest; index1 += 1, index2 += 1) { if (gaps1[index2] === true) { node = t1.childNodes[index1]; if (node.nodeName === '#text') { if (t2.childNodes[index2].nodeName === '#text' && node.data !== t2.childNodes[index2].data) { testI = index1; while (t1.childNodes.length > testI + 1 && t1.childNodes[testI + 1].nodeName === '#text') { testI += 1; if (t2.childNodes[index2].data === t1.childNodes[testI].data) { similarNode = true; break; } } if (!similarNode) { diffs.push(new Diff({ action: 'modifyTextElement', route: route.concat(index2), oldValue: node.data, newValue: t2.childNodes[index2].data })); return diffs; } } diffs.push(new Diff({ action: 'removeTextElement', route: route.concat(index2), value: node.data })); gaps1.splice(index2, 1); shortest = Math.min(gaps1.length, gaps2.length); index2 -= 1; } else { diffs.push(new Diff({ action: 'removeElement', route: route.concat(index2), element: cloneObj(node) })); gaps1.splice(index2, 1); shortest = Math.min(gaps1.length, gaps2.length); index2 -= 1; } } else if (gaps2[index2] === true) { node = t2.childNodes[index2]; if (node.nodeName === '#text') { diffs.push(new Diff({ action: 'addTextElement', route: route.concat(index2), value: node.data })); gaps1.splice(index2, 0, true); shortest = Math.min(gaps1.length, gaps2.length); index1 -= 1; } else { diffs.push(new Diff({ action: 'addElement', route: route.concat(index2), element: cloneObj(node) })); gaps1.splice(index2, 0, true); shortest = Math.min(gaps1.length, gaps2.length); index1 -= 1; } } else if (gaps1[index2] !== gaps2[index2]) { if (diffs.length > 0) { return diffs; } // group relocation group = subtrees[gaps1[index2]]; toGroup = Math.min(group.newValue, (t1.childNodes.length - group.length)); if (toGroup !== group.oldValue) { // Check whether destination nodes are different than originating ones. destinationDifferent = false; for (j = 0; j < group.length; j += 1) { if (!roughlyEqual(t1.childNodes[toGroup + j], t1.childNodes[group.oldValue + j], [], false, true)) { destinationDifferent = true; } } if (destinationDifferent) { return [new Diff({ action: 'relocateGroup', groupLength: group.length, from: group.oldValue, to: toGroup, route: route })]; } } } } return diffs; }, findValueDiff: function(t1, t2, route) { // Differences of value. Only useful if the value/selection/checked value // differs from what is represented in the DOM. For example in the case // of filled out forms, etc. var diffs = []; if (t1.selected !== t2.selected) { diffs.push(new Diff({ action: 'modifySelected', oldValue: t1.selected, newValue: t2.selected, route: route })); } if ((t1.value || t2.value) && t1.value !== t2.value && t1.nodeName !== 'OPTION') { diffs.push(new Diff({ action: 'modifyValue', oldValue: t1.value, newValue: t2.value, route: route })); } if (t1.checked !== t2.checked) { diffs.push(new Diff({ action: 'modifyChecked', oldValue: t1.checked, newValue: t2.checked, route: route })); } return diffs; }, // ===== Apply a virtual diff ===== applyVirtual: function(tree, diffs) { var dobj = this; if (diffs.length === 0) { return true; } diffs.forEach(function(diff) { dobj.applyVirtualDiff(tree, diff); }); return true; }, getFromVirtualRoute: function(tree, route) { var node = tree, parentNode, nodeIndex; route = route.slice(); while (route.length > 0) { if (!node.childNodes) { return false; } nodeIndex = route.splice(0, 1)[0]; parentNode = node; node = node.childNodes[nodeIndex]; } return { node: node, parentNode: parentNode, nodeIndex: nodeIndex }; }, applyVirtualDiff: function(tree, diff) { var routeInfo = this.getFromVirtualRoute(tree, diff.route), node = routeInfo.node, parentNode = routeInfo.parentNode, nodeIndex = routeInfo.nodeIndex, newNode, route, c; // pre-diff hook var info = { diff: diff, node: node }; if (this.preVirtualDiffApply(info)) { return true; } switch (diff.action) { case 'addAttribute': if (!node.attributes) { node.attributes = {}; } node.attributes[diff.name] = diff.value; if (diff.name === 'checked') { node.checked = true; } else if (diff.name === 'selected') { node.selected = true; } else if (node.nodeName === 'INPUT' && diff.name === 'value') { node.value = diff.value; } break; case 'modifyAttribute': node.attributes[diff.name] = diff.newValue; if (node.nodeName === 'INPUT' && diff.name === 'value') { node.value = diff.value; } break; case 'removeAttribute': delete node.attributes[diff.name]; if (Object.keys(node.attributes).length === 0) { delete node.attributes; } if (diff.name === 'checked') { node.checked = false; } else if (diff.name === 'selected') { delete node.selected; } else if (node.nodeName === 'INPUT' && diff.name === 'value') { delete node.value; } break; case 'modifyTextElement': node.data = diff.newValue; if (parentNode.nodeName === 'TEXTAREA') { parentNode.value = diff.newValue; } break; case 'modifyValue': node.value = diff.newValue; break; case 'modifyComment': node.data = diff.newValue; break; case 'modifyChecked': node.checked = diff.newValue; break; case 'modifySelected': node.selected = diff.newValue; break; case 'replaceElement': newNode = cloneObj(diff.newValue); newNode.outerDone = true; newNode.innerDone = true; newNode.valueDone = true; parentNode.childNodes[nodeIndex] = newNode; break; case 'relocateGroup': node.childNodes.splice(diff.from, diff.groupLength).reverse() .forEach(function(movedNode) { node.childNodes.splice(diff.to, 0, movedNode); }); break; case 'removeElement': parentNode.childNodes.splice(nodeIndex, 1); break; case 'addElement': route = diff.route.slice(); c = route.splice(route.length - 1, 1)[0]; node = this.getFromVirtualRoute(tree, route).node; newNode = cloneObj(diff.element); newNode.outerDone = true; newNode.innerDone = true; newNode.valueDone = true; if (!node.childNodes) { node.childNodes = []; } if (c >= node.childNodes.length) { node.childNodes.push(newNode); } else { node.childNodes.splice(c, 0, newNode); } break; case 'removeTextElement': parentNode.childNodes.splice(nodeIndex, 1); if (parentNode.nodeName === 'TEXTAREA') { delete parentNode.value; } break; case 'addTextElement': route = diff.route.slice(); c = route.splice(route.length - 1, 1)[0]; newNode = {}; newNode.nodeName = '#text'; newNode.data = diff.value; node = this.getFromVirtualRoute(tree, route).node; if (!node.childNodes) { node.childNodes = []; } if (c >= node.childNodes.length) { node.childNodes.push(newNode); } else { node.childNodes.splice(c, 0, newNode); } if (node.nodeName === 'TEXTAREA') { node.value = diff.newValue; } break; default: console.log('unknown action'); } // capture newNode for the callback info.newNode = newNode; this.postVirtualDiffApply(info); return; }, // ===== Apply a diff ===== apply: function(tree, diffs) { var dobj = this; if (diffs.length === 0) { return true; } diffs.forEach(function(diff) { if (!dobj.applyDiff(tree, diff)) { return false; } }); return true; }, getFromRoute: function(tree, route) { route = route.slice(); var c, node = tree; while (route.length > 0) { if (!node.childNodes) { return false; } c = route.splice(0, 1)[0]; node = node.childNodes[c]; } return node; }, applyDiff: function(tree, diff) { var node = this.getFromRoute(tree, diff.route), newNode, reference, route, c; // pre-diff hook var info = { diff: diff, node: node }; if (this.preDiffApply(info)) { return true; } switch (diff.action) { case 'addAttribute': if (!node || !node.setAttribute) { return false; } node.setAttribute(diff.name, diff.value); break; case 'modifyAttribute': if (!node || !node.setAttribute) { return false; } node.setAttribute(diff.name, diff.newValue); break; case 'removeAttribute': if (!node || !node.removeAttribute) { return false; } node.removeAttribute(diff.name); break; case 'modifyTextElement': if (!node || node.nodeType !== 3) { return false; } this.textDiff(node, node.data, diff.oldValue, diff.newValue); break; case 'modifyValue': if (!node || typeof node.value === 'undefined') { return false; } node.value = diff.newValue; break; case 'modifyComment': if (!node || typeof node.data === 'undefined') { return false; } this.textDiff(node, node.data, diff.oldValue, diff.newValue); break; case 'modifyChecked': if (!node || typeof node.checked === 'undefined') { return false; } node.checked = diff.newValue; break; case 'modifySelected': if (!node || typeof node.selected === 'undefined') { return false; } node.selected = diff.newValue; break; case 'replaceElement': node.parentNode.replaceChild(this.objToNode(diff.newValue, node.namespaceURI === 'http://www.w3.org/2000/svg'), node); break; case 'relocateGroup': Array.apply(null, new Array(diff.groupLength)).map(function() { return node.removeChild(node.childNodes[diff.from]); }).forEach(function(childNode, index) { if (index === 0) { reference = node.childNodes[diff.to]; } node.insertBefore(childNode, reference); }); break; case 'removeElement': node.parentNode.removeChild(node); break; case 'addElement': route = diff.route.slice(); c = route.splice(route.length - 1, 1)[0]; node = this.getFromRoute(tree, route); node.insertBefore(this.objToNode(diff.element, node.namespaceURI === 'http://www.w3.org/2000/svg'), node.childNodes[c]); break; case 'removeTextElement': if (!node || node.nodeType !== 3) { return false; } node.parentNode.removeChild(node); break; case 'addTextElement': route = diff.route.slice(); c = route.splice(route.length - 1, 1)[0]; newNode = document.createTextNode(diff.value); node = this.getFromRoute(tree, route); if (!node || !node.childNodes) { return false; } node.insertBefore(newNode, node.childNodes[c]); break; default: console.log('unknown action'); } // if a new node was created, we might be interested in it // post diff hook info.newNode = newNode; this.postDiffApply(info); return true; }, // ===== Undo a diff ===== undo: function(tree, diffs) { diffs = diffs.slice(); var dobj = this; if (!diffs.length) { diffs = [diffs]; } diffs.reverse(); diffs.forEach(function(diff) { dobj.undoDiff(tree, diff); }); }, undoDiff: function(tree, diff) { switch (diff.action) { case 'addAttribute': diff.action = 'removeAttribute'; this.applyDiff(tree, diff); break; case 'modifyAttribute': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'removeAttribute': diff.action = 'addAttribute'; this.applyDiff(tree, diff); break; case 'modifyTextElement': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'modifyValue': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'modifyComment': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'modifyChecked': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'modifySelected': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'replaceElement': swap(diff, 'oldValue', 'newValue'); this.applyDiff(tree, diff); break; case 'relocateGroup': swap(diff, 'from', 'to'); this.applyDiff(tree, diff); break; case 'removeElement': diff.action = 'addElement'; this.applyDiff(tree, diff); break; case 'addElement': diff.action = 'removeElement'; this.applyDiff(tree, diff); break; case 'removeTextElement': diff.action = 'addTextElement'; this.applyDiff(tree, diff); break; case 'addTextElement': diff.action = 'removeTextElement'; this.applyDiff(tree, diff); break; default: console.log('unknown action'); } } }; if (typeof exports !== 'undefined') { if (typeof module !== 'undefined' && module.exports) { exports = module.exports = diffDOM; } exports.diffDOM = diffDOM; } else { // `window` in the browser, or `exports` on the server this.diffDOM = diffDOM; } }.call(this));