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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const EventEmitter = require("resource://devtools/shared/event-emitter.js");
// This serves as a local cache for the classes applied to each of the node we care about
// here.
// The map is indexed by NodeFront. Any time a new node is selected in the inspector, an
// entry is added here, indexed by the corresponding NodeFront.
// The value for each entry is an array of each of the class this node has. Items of this
// array are objects like: { name, isApplied } where the name is the class itself, and
// isApplied is a Boolean indicating if the class is applied on the node or not.
const CLASSES = new WeakMap();
/**
* Manages the list classes per DOM elements we care about.
* The actual list is stored in the CLASSES const, indexed by NodeFront objects.
* The responsibility of this class is to be the source of truth for anyone who wants to
* know which classes a given NodeFront has, and which of these are enabled and which are
* disabled.
* It also reacts to DOM mutations so the list of classes is up to date with what is in
* the DOM.
* It can also be used to enable/disable a given class, or add classes.
*
* @param {Inspector} inspector
* The current inspector instance.
*/
class ClassList {
constructor(inspector) {
EventEmitter.decorate(this);
this.inspector = inspector;
this.onMutations = this.onMutations.bind(this);
this.inspector.on("markupmutation", this.onMutations);
this.classListProxyNode = this.inspector.panelDoc.createElement("div");
this.previewClasses = [];
this.unresolvedStateChanges = [];
}
destroy() {
this.inspector.off("markupmutation", this.onMutations);
this.inspector = null;
this.classListProxyNode = null;
}
/**
* The current node selection (which only returns if the node is an ELEMENT_NODE type
* since that's the only type this model can work with.)
*/
get currentNode() {
if (
this.inspector.selection.isElementNode() &&
!this.inspector.selection.isPseudoElementNode()
) {
return this.inspector.selection.nodeFront;
}
return null;
}
/**
* The class states for the current node selection. See the documentation of the CLASSES
* constant.
*/
get currentClasses() {
if (!this.currentNode) {
return [];
}
if (!CLASSES.has(this.currentNode)) {
// Use the proxy node to get a clean list of classes.
this.classListProxyNode.className = this.currentNode.className;
const nodeClasses = [...new Set([...this.classListProxyNode.classList])]
.filter(
className =>
!this.previewClasses.some(
previewClass =>
previewClass.className === className &&
!previewClass.wasAppliedOnNode
)
)
.map(name => {
return { name, isApplied: true };
});
CLASSES.set(this.currentNode, nodeClasses);
}
return CLASSES.get(this.currentNode);
}
/**
* Same as currentClasses, but returns it in the form of a className string, where only
* enabled classes are added.
*/
get currentClassesPreview() {
const currentClasses = this.currentClasses
.filter(({ isApplied }) => isApplied)
.map(({ name }) => name);
const previewClasses = this.previewClasses
.filter(previewClass => !currentClasses.includes(previewClass.className))
.filter(item => item !== "")
.map(({ className }) => className);
return currentClasses.concat(previewClasses).join(" ").trim();
}
/**
* Set the state for a given class on the current node.
*
* @param {String} name
* The class which state should be changed.
* @param {Boolean} isApplied
* True if the class should be enabled, false otherwise.
* @return {Promise} Resolves when the change has been made in the DOM.
*/
setClassState(name, isApplied) {
// Do the change in our local model.
const nodeClasses = this.currentClasses;
nodeClasses.find(({ name: cName }) => cName === name).isApplied = isApplied;
return this.applyClassState();
}
/**
* Add several classes to the current node at once.
*
* @param {String} classNameString
* The string that contains all classes.
* @return {Promise} Resolves when the change has been made in the DOM.
*/
addClassName(classNameString) {
this.classListProxyNode.className = classNameString;
this.eraseClassPreview();
return Promise.all(
[...new Set([...this.classListProxyNode.classList])].map(name => {
return this.addClass(name);
})
);
}
/**
* Add a class to the current node at once.
*
* @param {String} name
* The class to be added.
* @return {Promise} Resolves when the change has been made in the DOM.
*/
addClass(name) {
// Avoid adding the same class again.
if (this.currentClasses.some(({ name: cName }) => cName === name)) {
return Promise.resolve();
}
// Change the local model, so we retain the state of the existing classes.
this.currentClasses.push({ name, isApplied: true });
return this.applyClassState();
}
/**
* Used internally by other functions like addClass or setClassState. Actually applies
* the class change to the DOM.
*
* @return {Promise} Resolves when the change has been made in the DOM.
*/
applyClassState() {
// If there is no valid inspector selection, bail out silently. No need to report an
// error here.
if (!this.currentNode) {
return Promise.resolve();
}
// Remember which node & className we applied until their mutation event is received, so we
// can filter out dom mutations that are caused by us in onMutations, even in situations when
// a new change is applied before that the event of the previous one has been received yet
this.unresolvedStateChanges.push({
node: this.currentNode,
className: this.currentClassesPreview,
});
// Apply the change to the node.
const mod = this.currentNode.startModifyingAttributes();
mod.setAttribute("class", this.currentClassesPreview);
return mod.apply();
}
onMutations(mutations) {
for (const { type, target, attributeName } of mutations) {
// Only care if this mutation is for the class attribute.
if (type !== "attributes" || attributeName !== "class") {
continue;
}
const isMutationForOurChange = this.unresolvedStateChanges.some(
previousStateChange =>
previousStateChange.node === target &&
previousStateChange.className === target.className
);
if (!isMutationForOurChange) {
CLASSES.delete(target);
if (target === this.currentNode) {
this.emit("current-node-class-changed");
}
} else {
this.removeResolvedStateChanged(target, target.className);
}
}
}
/**
* Get the available classNames in the document where the current selected node lives:
* - the one already used on elements of the document
* - the one defined in Stylesheets of the document
*
* @param {String} filter: A string the classNames should start with (an insensitive
* case matching will be done).
* @returns {Promise<Array<String>>} A promise that resolves with an array of strings
* matching the passed filter.
*/
getClassNames(filter) {
return this.currentNode.inspectorFront.pageStyle.getAttributesInOwnerDocument(
filter,
"class",
this.currentNode
);
}
previewClass(inputClasses) {
if (
this.previewClasses
.map(previewClass => previewClass.className)
.join(" ") !== inputClasses
) {
this.previewClasses = [];
inputClasses.split(" ").forEach(className => {
this.previewClasses.push({
className,
wasAppliedOnNode: this.isClassAlreadyApplied(className),
});
});
this.applyClassState();
}
}
eraseClassPreview() {
this.previewClass("");
}
removeResolvedStateChanged(currentNode, currentClassesPreview) {
this.unresolvedStateChanges.splice(
0,
this.unresolvedStateChanges.findIndex(
previousState =>
previousState.node === currentNode &&
previousState.className === currentClassesPreview
) + 1
);
}
isClassAlreadyApplied(className) {
return this.currentClasses.some(({ name }) => name === className);
}
}
module.exports = ClassList;