Move Add-on SDK source to toolkit/jetpack

toolkit/jetpack/sdk/context-menu/core.js

@@ -0,0 +1,384 @@
+/* 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";
+
+const Contexts = require("./context");
+const Readers = require("./readers");
+const Component = require("../ui/component");
+const { Class } = require("../core/heritage");
+const { map, filter, object, reduce, keys, symbols,
+        pairs, values, each, some, isEvery, count } = require("../util/sequence");
+const { loadModule } = require("framescript/manager");
+const { Cu, Cc, Ci } = require("chrome");
+const prefs = require("sdk/preferences/service");
+
+const globalMessageManager = Cc["@mozilla.org/globalmessagemanager;1"]
+                              .getService(Ci.nsIMessageListenerManager);
+const preferencesService = Cc["@mozilla.org/preferences-service;1"].
+                            getService(Ci.nsIPrefService).
+                            getBranch(null);
+
+
+const readTable = Symbol("context-menu/read-table");
+const nameTable = Symbol("context-menu/name-table");
+const onContext = Symbol("context-menu/on-context");
+const isMatching = Symbol("context-menu/matching-handler?");
+
+exports.onContext = onContext;
+exports.readTable = readTable;
+exports.nameTable = nameTable;
+
+
+const propagateOnContext = (item, data) =>
+  each(child => child[onContext](data), item.state.children);
+
+const isContextMatch = item => !item[isMatching] || item[isMatching]();
+
+// For whatever reason addWeakMessageListener does not seems to work as our
+// instance seems to dropped even though it's alive. This is simple workaround
+// to avoid dead object excetptions.
+const WeakMessageListener = function(receiver, handler="receiveMessage") {
+  this.receiver = receiver
+  this.handler = handler
+};
+WeakMessageListener.prototype = {
+  constructor: WeakMessageListener,
+  receiveMessage(message) {
+    if (Cu.isDeadWrapper(this.receiver)) {
+      message.target.messageManager.removeMessageListener(message.name, this);
+    }
+    else {
+      this.receiver[this.handler](message);
+    }
+  }
+};
+
+const OVERFLOW_THRESH = "extensions.addon-sdk.context-menu.overflowThreshold";
+const onMessage = Symbol("context-menu/message-listener");
+const onPreferceChange = Symbol("context-menu/preference-change");
+const ContextMenuExtension = Class({
+  extends: Component,
+  initialize: Component,
+  setup() {
+    const messageListener = new WeakMessageListener(this, onMessage);
+    loadModule(globalMessageManager, "framescript/context-menu", true, "onContentFrame");
+    globalMessageManager.addMessageListener("sdk/context-menu/read", messageListener);
+    globalMessageManager.addMessageListener("sdk/context-menu/readers?", messageListener);
+
+    preferencesService.addObserver(OVERFLOW_THRESH, this, false);
+  },
+  observe(_, __, name) {
+    if (name === OVERFLOW_THRESH) {
+      const overflowThreshold = prefs.get(OVERFLOW_THRESH, 10);
+      this[Component.patch]({overflowThreshold});
+    }
+  },
+  [onMessage]({name, data, target}) {
+    if (name === "sdk/context-menu/read")
+      this[onContext]({target, data});
+    if (name === "sdk/context-menu/readers?")
+      target.messageManager.sendAsyncMessage("sdk/context-menu/readers",
+                                             JSON.parse(JSON.stringify(this.state.readers)));
+  },
+  [Component.initial](options={}, children) {
+    const element = options.element || null;
+    const target = options.target || null;
+    const readers = Object.create(null);
+    const users = Object.create(null);
+    const registry = new WeakSet();
+    const overflowThreshold = prefs.get(OVERFLOW_THRESH, 10);
+
+    return { target, children: [], readers, users, element,
+             registry, overflowThreshold };
+  },
+  [Component.isUpdated](before, after) {
+    // Update only if target changed, since there is no point in re-rendering
+    // when children are. Also new items added won't be in sync with a latest
+    // context target so we should really just render before drawing context
+    // menu.
+    return before.target !== after.target;
+  },
+  [Component.render]({element, children, overflowThreshold}) {
+    if (!element) return null;
+
+    const items = children.filter(isContextMatch);
+    const body = items.length === 0 ? items :
+                 items.length < overflowThreshold ? [new Separator(),
+                                                     ...items] :
+                 [{tagName: "menu",
+                   className: "sdk-context-menu-overflow-menu",
+                   label: "Add-ons",
+                   accesskey: "A",
+                   children: [{tagName: "menupopup",
+                               children: items}]}];
+    return {
+      element: element,
+      tagName: "menugroup",
+      style: "-moz-box-orient: vertical;",
+      className: "sdk-context-menu-extension",
+      children: body
+    }
+  },
+  // Adds / remove child to it's own list.
+  add(item) {
+    this[Component.patch]({children: this.state.children.concat(item)});
+  },
+  remove(item) {
+    this[Component.patch]({
+      children: this.state.children.filter(x => x !== item)
+    });
+  },
+  register(item) {
+    const { users, registry } = this.state;
+    if (registry.has(item)) return;
+    registry.add(item);
+
+    // Each (ContextHandler) item has a readTable that is a
+    // map of keys to readers extracting them from the content.
+    // During the registraction we update intrnal record of unique
+    // readers and users per reader. Most context will have a reader
+    // shared across all instances there for map of users per reader
+    // is stored separately from the reader so that removing reader
+    // will occur only when no users remain.
+    const table = item[readTable];
+    // Context readers store data in private symbols so we need to
+    // collect both table keys and private symbols.
+    const names = [...keys(table), ...symbols(table)];
+    const readers = map(name => table[name], names);
+    // Create delta for registered readers that will be merged into
+    // internal readers table.
+    const added = filter(x => !users[x.id], readers);
+    const delta = object(...map(x => [x.id, x], added));
+
+    const update = reduce((update, reader) => {
+      const n = update[reader.id] || 0;
+      update[reader.id] = n + 1;
+      return update;
+    }, Object.assign({}, users), readers);
+
+    // Patch current state with a changes that registered item caused.
+    this[Component.patch]({users: update,
+                           readers: Object.assign(this.state.readers, delta)});
+
+    if (count(added)) {
+      globalMessageManager.broadcastAsyncMessage("sdk/context-menu/readers",
+                                                 JSON.parse(JSON.stringify(delta)));
+    }
+  },
+  unregister(item) {
+    const { users, registry } = this.state;
+    if (!registry.has(item)) return;
+    registry.delete(item);
+
+    const table = item[readTable];
+    const names = [...keys(table), ...symbols(table)];
+    const readers = map(name => table[name], names);
+    const update = reduce((update, reader) => {
+      update[reader.id] = update[reader.id] - 1;
+      return update;
+    }, Object.assign({}, users), readers);
+    const removed = filter(id => !update[id], keys(update));
+    const delta = object(...map(x => [x, null], removed));
+
+    this[Component.patch]({users: update,
+                           readers: Object.assign(this.state.readers, delta)});
+
+    if (count(removed)) {
+      globalMessageManager.broadcastAsyncMessage("sdk/context-menu/readers",
+                                                 JSON.parse(JSON.stringify(delta)));
+    }
+  },
+
+  [onContext]({data, target}) {
+    propagateOnContext(this, data);
+    const document = target.ownerDocument;
+    const element = document.getElementById("contentAreaContextMenu");
+
+    this[Component.patch]({target: data, element: element});
+  }
+});this,
+exports.ContextMenuExtension = ContextMenuExtension;
+
+// Takes an item options and
+const makeReadTable = ({context, read}) => {
+  // Result of this function is a tuple of all readers &
+  // name, reader id pairs.
+
+  // Filter down to contexts that have a reader associated.
+  const contexts = filter(context => context.read, context);
+  // Merge all contexts read maps to a single hash, note that there should be
+  // no name collisions as context implementations expect to use private
+  // symbols for storing it's read data.
+  return Object.assign({}, ...map(({read}) => read, contexts), read);
+}
+
+const readTarget = (nameTable, data) =>
+  object(...map(([name, id]) => [name, data[id]], nameTable))
+
+const ContextHandler = Class({
+  extends: Component,
+  initialize: Component,
+  get context() {
+    return this.state.options.context;
+  },
+  get read() {
+    return this.state.options.read;
+  },
+  [Component.initial](options) {
+    return {
+      table: makeReadTable(options),
+      requiredContext: filter(context => context.isRequired, options.context),
+      optionalContext: filter(context => !context.isRequired, options.context)
+    }
+  },
+  [isMatching]() {
+    const {target, requiredContext, optionalContext} = this.state;
+    return isEvery(context => context.isCurrent(target), requiredContext) &&
+            (count(optionalContext) === 0 ||
+             some(context => context.isCurrent(target), optionalContext));
+  },
+  setup() {
+    const table = makeReadTable(this.state.options);
+    this[readTable] = table;
+    this[nameTable] = [...map(symbol => [symbol, table[symbol].id], symbols(table)),
+                       ...map(name => [name, table[name].id], keys(table))];
+
+
+    contextMenu.register(this);
+
+    each(child => contextMenu.remove(child), this.state.children);
+    contextMenu.add(this);
+  },
+  dispose() {
+    contextMenu.remove(this);
+
+    each(child => contextMenu.unregister(child), this.state.children);
+    contextMenu.unregister(this);
+  },
+  // Internal `Symbol("onContext")` method is invoked when "contextmenu" event
+  // occurs in content process. Context handles with children delegate to each
+  // child and patch it's internal state to reflect new contextmenu target.
+  [onContext](data) {
+    propagateOnContext(this, data);
+    this[Component.patch]({target: readTarget(this[nameTable], data)});
+  }
+});
+const isContextHandler = item => item instanceof ContextHandler;
+
+exports.ContextHandler = ContextHandler;
+
+const Menu = Class({
+  extends: ContextHandler,
+  [isMatching]() {
+    return ContextHandler.prototype[isMatching].call(this) &&
+           this.state.children.filter(isContextHandler)
+                              .some(isContextMatch);
+  },
+  [Component.render]({children, options}) {
+    const items = children.filter(isContextMatch);
+    return {tagName: "menu",
+            className: "sdk-context-menu menu-iconic",
+            label: options.label,
+            accesskey: options.accesskey,
+            image: options.icon,
+            children: [{tagName: "menupopup",
+                        children: items}]};
+  }
+});
+exports.Menu = Menu;
+
+const onCommand = Symbol("context-menu/item/onCommand");
+const Item = Class({
+  extends: ContextHandler,
+  get onClick() {
+    return this.state.options.onClick;
+  },
+  [Component.render]({options}) {
+    const {label, icon, accesskey} = options;
+    return {tagName: "menuitem",
+            className: "sdk-context-menu-item menuitem-iconic",
+            label,
+            accesskey,
+            image: icon,
+            oncommand: this};
+  },
+  handleEvent(event) {
+    if (this.onClick)
+      this.onClick(this.state.target);
+  }
+});
+exports.Item = Item;
+
+var Separator = Class({
+  extends: Component,
+  initialize: Component,
+  [Component.render]() {
+    return {tagName: "menuseparator",
+            className: "sdk-context-menu-separator"}
+  },
+  [onContext]() {
+
+  }
+});
+exports.Separator = Separator;
+
+exports.Contexts = Contexts;
+exports.Readers = Readers;
+
+const createElement = (vnode, {document}) => {
+   const node = vnode.namespace ?
+              document.createElementNS(vnode.namespace, vnode.tagName) :
+              document.createElement(vnode.tagName);
+
+   node.setAttribute("data-component-path", vnode[Component.path]);
+
+   each(([key, value]) => {
+     if (key === "tagName") {
+       return;
+     }
+     if (key === "children") {
+       return;
+     }
+
+     if (key.startsWith("on")) {
+       node.addEventListener(key.substr(2), value)
+       return;
+     }
+
+     if (typeof(value) !== "object" &&
+         typeof(value) !== "function" &&
+         value !== void(0) &&
+         value !== null)
+    {
+       if (key === "className") {
+         node[key] = value;
+       }
+       else {
+         node.setAttribute(key, value);
+       }
+       return;
+     }
+   }, pairs(vnode));
+
+  each(child => node.appendChild(createElement(child, {document})), vnode.children);
+  return node;
+};
+
+const htmlWriter = tree => {
+  if (tree !== null) {
+    const root = tree.element;
+    const node = createElement(tree, {document: root.ownerDocument});
+    const before = root.querySelector("[data-component-path='/']");
+    if (before) {
+      root.replaceChild(node, before);
+    } else {
+      root.appendChild(node);
+    }
+  }
+};
+
+
+const contextMenu = ContextMenuExtension();
+exports.contextMenu = contextMenu;
+Component.mount(contextMenu, htmlWriter);