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-rw-r--r--toolkit/mozapps/extensions/content/view-controller.js201
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diff --git a/toolkit/mozapps/extensions/content/view-controller.js b/toolkit/mozapps/extensions/content/view-controller.js
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+/* import-globals-from /toolkit/content/customElements.js */
+/* import-globals-from aboutaddonsCommon.js */
+/* exported loadView */
+
+// Used by external callers to load a specific view into the manager
+function loadView(viewId) {
+ if (!gViewController.readyForLoadView) {
+ throw new Error("loadView called before about:addons is initialized");
+ }
+ gViewController.loadView(viewId);
+}
+
+/**
+ * Helper for saving and restoring the scroll offsets when a previously loaded
+ * view is accessed again.
+ */
+var ScrollOffsets = {
+ _key: null,
+ _offsets: new Map(),
+ canRestore: true,
+
+ setView(historyEntryId) {
+ this._key = historyEntryId;
+ this.canRestore = true;
+ },
+
+ getPosition() {
+ if (!this.canRestore) {
+ return { top: 0, left: 0 };
+ }
+ let { scrollTop: top, scrollLeft: left } = document.documentElement;
+ return { top, left };
+ },
+
+ save() {
+ if (this._key) {
+ this._offsets.set(this._key, this.getPosition());
+ }
+ },
+
+ restore() {
+ let { top = 0, left = 0 } = this._offsets.get(this._key) || {};
+ window.scrollTo({ top, left, behavior: "auto" });
+ },
+};
+
+var gViewController = {
+ currentViewId: null,
+ readyForLoadView: false,
+ get defaultViewId() {
+ if (!isDiscoverEnabled()) {
+ return "addons://list/extension";
+ }
+ return "addons://discover/";
+ },
+ isLoading: true,
+ // All historyEntryId values must be unique within one session, because the
+ // IDs are used to map history entries to page state. It is not possible to
+ // see whether a historyEntryId was used in history entries before this page
+ // was loaded, so start counting from a random value to avoid collisions.
+ // This is used for scroll offsets in aboutaddons.js
+ nextHistoryEntryId: Math.floor(Math.random() * 2 ** 32),
+ views: {},
+
+ initialize(container) {
+ this.container = container;
+
+ window.addEventListener("popstate", this);
+ window.addEventListener("unload", this, { once: true });
+ Services.obs.addObserver(this, "EM-ping");
+ },
+
+ handleEvent(e) {
+ if (e.type == "popstate") {
+ this.renderState(e.state);
+ return;
+ }
+
+ if (e.type == "unload") {
+ Services.obs.removeObserver(this, "EM-ping");
+ // eslint-disable-next-line no-useless-return
+ return;
+ }
+ },
+
+ observe(subject, topic, data) {
+ if (topic == "EM-ping") {
+ this.readyForLoadView = true;
+ Services.obs.notifyObservers(window, "EM-pong");
+ }
+ },
+
+ notifyEMLoaded() {
+ this.readyForLoadView = true;
+ Services.obs.notifyObservers(window, "EM-loaded");
+ },
+
+ notifyEMUpdateCheckFinished() {
+ // Notify the observer about a completed update check (currently only used in tests).
+ Services.obs.notifyObservers(null, "EM-update-check-finished");
+ },
+
+ defineView(viewName, renderFunction) {
+ if (this.views[viewName]) {
+ throw new Error(
+ `about:addons view ${viewName} should not be defined twice`
+ );
+ }
+ this.views[viewName] = renderFunction;
+ },
+
+ parseViewId(viewId) {
+ const matchRegex = /^addons:\/\/([^\/]+)\/(.*)$/;
+ const [, viewType, viewParam] = viewId.match(matchRegex) || [];
+ return { type: viewType, param: decodeURIComponent(viewParam) };
+ },
+
+ loadView(viewId, replace = false) {
+ viewId = viewId.startsWith("addons://") ? viewId : `addons://${viewId}`;
+ if (viewId == this.currentViewId) {
+ return Promise.resolve();
+ }
+
+ // Always rewrite history state instead of pushing incorrect state for initial load.
+ replace = replace || !this.currentViewId;
+
+ const state = {
+ view: viewId,
+ previousView: replace ? null : this.currentViewId,
+ historyEntryId: ++this.nextHistoryEntryId,
+ };
+ if (replace) {
+ history.replaceState(state, "");
+ } else {
+ history.pushState(state, "");
+ }
+ return this.renderState(state);
+ },
+
+ async renderState(state) {
+ let { param, type } = this.parseViewId(state.view);
+
+ if (!type || this.views[type] == null) {
+ console.warn(`No view for ${type} ${param}, switching to default`);
+ this.resetState();
+ return;
+ }
+
+ this.currentViewId = state.view;
+ this.isLoading = true;
+
+ // Perform tasks before view load
+ document.dispatchEvent(
+ new CustomEvent("view-selected", {
+ detail: { id: state.view, param, type },
+ })
+ );
+
+ // Render the fragment
+ this.container.setAttribute("current-view", type);
+ let fragment = await this.views[type](param);
+
+ // Clear and append the fragment
+ if (fragment) {
+ ScrollOffsets.save();
+ ScrollOffsets.setView(state.historyEntryId);
+
+ this.container.textContent = "";
+ this.container.append(fragment);
+
+ // Most content has been rendered at this point. The only exception are
+ // recommendations in the discovery pane and extension/theme list, because
+ // they rely on remote data. If loaded before, then these may be rendered
+ // within one tick, so wait a frame before restoring scroll offsets.
+ await new Promise(resolve => {
+ window.requestAnimationFrame(() => {
+ ScrollOffsets.restore();
+ resolve();
+ });
+ });
+ } else {
+ // Reset to default view if no given content
+ this.resetState();
+ return;
+ }
+
+ this.isLoading = false;
+
+ document.dispatchEvent(new CustomEvent("view-loaded"));
+ },
+
+ resetState() {
+ return this.loadView(this.defaultViewId, true);
+ },
+};