4 files changed, 437 insertions, 0 deletions
diff --git a/remote/cdp/targets/MainProcessTarget.sys.mjs b/remote/cdp/targets/MainProcessTarget.sys.mjs
new file mode 100644
index 0000000000..1f32b5bde5
--- /dev/null
+++ b/remote/cdp/targets/MainProcessTarget.sys.mjs
@@ -0,0 +1,55 @@
+/* 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/. */
+
+import { Target } from "chrome://remote/content/cdp/targets/Target.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  MainProcessSession:
+    "chrome://remote/content/cdp/sessions/MainProcessSession.sys.mjs",
+  RemoteAgent: "chrome://remote/content/components/RemoteAgent.sys.mjs",
+});
+
+/**
+ * The main process Target.
+ *
+ * Matches BrowserDevToolsAgentHost from chromium, and only support a couple of Domains:
+ * https://cs.chromium.org/chromium/src/content/browser/devtools/browser_devtools_agent_host.cc?dr=CSs&g=0&l=80-91
+ */
+export class MainProcessTarget extends Target {
+  /*
+   * @param TargetList targetList
+   */
+  constructor(targetList) {
+    super(targetList, lazy.MainProcessSession);
+
+    this.type = "browser";
+
+    // Define the HTTP path to query this target
+    this.path = `/devtools/browser/${this.id}`;
+  }
+
+  get wsDebuggerURL() {
+    const { host, port } = lazy.RemoteAgent;
+    return `ws://${host}:${port}${this.path}`;
+  }
+
+  toString() {
+    return `[object MainProcessTarget]`;
+  }
+
+  toJSON() {
+    return {
+      description: "Main process target",
+      devtoolsFrontendUrl: "",
+      faviconUrl: "",
+      id: this.id,
+      title: "Main process target",
+      type: this.type,
+      url: "",
+      webSocketDebuggerUrl: this.wsDebuggerURL,
+    };
+  }
+}
diff --git a/remote/cdp/targets/TabTarget.sys.mjs b/remote/cdp/targets/TabTarget.sys.mjs
new file mode 100644
index 0000000000..a35b0c3f07
--- /dev/null
+++ b/remote/cdp/targets/TabTarget.sys.mjs
@@ -0,0 +1,161 @@
+/* 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/. */
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+import { Target } from "chrome://remote/content/cdp/targets/Target.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  RemoteAgent: "chrome://remote/content/components/RemoteAgent.sys.mjs",
+  TabManager: "chrome://remote/content/shared/TabManager.sys.mjs",
+  TabSession: "chrome://remote/content/cdp/sessions/TabSession.sys.mjs",
+});
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "Favicons",
+  "@mozilla.org/browser/favicon-service;1",
+  "nsIFaviconService"
+);
+
+/**
+ * Target for a local tab or a remoted frame.
+ */
+export class TabTarget extends Target {
+  /**
+   * @param {TargetList} targetList
+   * @param {BrowserElement} browser
+   */
+  constructor(targetList, browser) {
+    super(targetList, lazy.TabSession);
+
+    this.browser = browser;
+
+    // The tab target uses a unique id as shared with WebDriver to reference
+    // a specific tab.
+    this.id = lazy.TabManager.getIdForBrowser(browser);
+
+    // Define the HTTP path to query this target
+    this.path = `/devtools/page/${this.id}`;
+
+    Services.obs.addObserver(this, "message-manager-disconnect");
+  }
+
+  destructor() {
+    Services.obs.removeObserver(this, "message-manager-disconnect");
+    super.destructor();
+  }
+
+  get browserContextId() {
+    return parseInt(this.browser.getAttribute("usercontextid"));
+  }
+
+  get browsingContext() {
+    return this.browser.browsingContext;
+  }
+
+  get mm() {
+    return this.browser.messageManager;
+  }
+
+  get window() {
+    return this.browser.ownerGlobal;
+  }
+
+  get tab() {
+    return this.window.gBrowser.getTabForBrowser(this.browser);
+  }
+
+  /**
+   * Determines if the content browser remains attached
+   * to its parent chrome window.
+   *
+   * We determine this by checking if the <browser> element
+   * is still attached to the DOM.
+   *
+   * @returns {boolean}
+   *     True if target's browser is still attached,
+   *     false if it has been disconnected.
+   */
+  get closed() {
+    return !this.browser || !this.browser.isConnected;
+  }
+
+  get description() {
+    return "";
+  }
+
+  get frontendURL() {
+    return null;
+  }
+
+  /** @returns {Promise<string|null>} */
+  get faviconUrl() {
+    return new Promise((resolve, reject) => {
+      lazy.Favicons.getFaviconURLForPage(this.browser.currentURI, url => {
+        if (url) {
+          resolve(url.spec);
+        } else {
+          resolve(null);
+        }
+      });
+    });
+  }
+
+  get title() {
+    return this.browsingContext.currentWindowGlobal.documentTitle;
+  }
+
+  get type() {
+    return "page";
+  }
+
+  get url() {
+    return this.browser.currentURI.spec;
+  }
+
+  get wsDebuggerURL() {
+    const { host, port } = lazy.RemoteAgent;
+    return `ws://${host}:${port}${this.path}`;
+  }
+
+  toString() {
+    return `[object Target ${this.id}]`;
+  }
+
+  toJSON() {
+    return {
+      description: this.description,
+      devtoolsFrontendUrl: this.frontendURL,
+      // TODO(ato): toJSON cannot be marked async )-:
+      faviconUrl: "",
+      id: this.id,
+      // Bug 1680817: Fails to encode some UTF-8 characters
+      // title: this.title,
+      type: this.type,
+      url: this.url,
+      webSocketDebuggerUrl: this.wsDebuggerURL,
+    };
+  }
+
+  // nsIObserver
+
+  observe(subject, topic, data) {
+    if (subject === this.mm && subject == "message-manager-disconnect") {
+      // disconnect debugging target if <browser> is disconnected,
+      // otherwise this is just a host process change
+      if (this.closed) {
+        this.disconnect();
+      }
+    }
+  }
+
+  // XPCOM
+
+  get QueryInterface() {
+    return ChromeUtils.generateQI(["nsIHttpRequestHandler", "nsIObserver"]);
+  }
+}
diff --git a/remote/cdp/targets/Target.sys.mjs b/remote/cdp/targets/Target.sys.mjs
new file mode 100644
index 0000000000..9264110c37
--- /dev/null
+++ b/remote/cdp/targets/Target.sys.mjs
@@ -0,0 +1,62 @@
+/* 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/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  CDPConnection: "chrome://remote/content/cdp/CDPConnection.sys.mjs",
+  generateUUID: "chrome://remote/content/shared/UUID.sys.mjs",
+  WebSocketHandshake:
+    "chrome://remote/content/server/WebSocketHandshake.sys.mjs",
+});
+
+/**
+ * Base class for all the targets.
+ */
+export class Target {
+  /**
+   * @param {TargetList} targetList
+   * @param {Class} sessionClass
+   */
+  constructor(targetList, sessionClass) {
+    // Save a reference to TargetList instance in order to expose it to:
+    // domains/parent/Target.jsm
+    this.targetList = targetList;
+
+    // When a new connection is made to this target,
+    // we will instantiate a new session based on this given class.
+    // The session class is specific to each target's kind and is passed
+    // by the inheriting class.
+    this.sessionClass = sessionClass;
+
+    // There can be more than one connection if multiple clients connect to the remote agent.
+    this.connections = new Set();
+    this.id = lazy.generateUUID();
+  }
+
+  /**
+   * Close all active connections made to this target.
+   */
+  destructor() {
+    for (const conn of this.connections) {
+      conn.close();
+    }
+  }
+
+  // nsIHttpRequestHandler
+
+  async handle(request, response) {
+    const webSocket = await lazy.WebSocketHandshake.upgrade(request, response);
+    const conn = new lazy.CDPConnection(webSocket, response._connection);
+    const session = new this.sessionClass(conn, this);
+    conn.registerSession(session);
+    this.connections.add(conn);
+  }
+
+  // XPCOM
+
+  get QueryInterface() {
+    return ChromeUtils.generateQI(["nsIHttpRequestHandler"]);
+  }
+}
diff --git a/remote/cdp/targets/TargetList.sys.mjs b/remote/cdp/targets/TargetList.sys.mjs
new file mode 100644
index 0000000000..a68b36763f
--- /dev/null
+++ b/remote/cdp/targets/TargetList.sys.mjs
@@ -0,0 +1,159 @@
+/* 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/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  EventEmitter: "resource://gre/modules/EventEmitter.sys.mjs",
+
+  MainProcessTarget:
+    "chrome://remote/content/cdp/targets/MainProcessTarget.sys.mjs",
+  TabManager: "chrome://remote/content/shared/TabManager.sys.mjs",
+  TabObserver: "chrome://remote/content/cdp/observers/TargetObserver.sys.mjs",
+  TabTarget: "chrome://remote/content/cdp/targets/TabTarget.sys.mjs",
+});
+
+export class TargetList {
+  constructor() {
+    // Target ID -> Target
+    this._targets = new Map();
+
+    lazy.EventEmitter.decorate(this);
+  }
+
+  /**
+   * Start listing and listening for all the debuggable targets
+   */
+  async watchForTargets() {
+    await this.watchForTabs();
+  }
+
+  unwatchForTargets() {
+    this.unwatchForTabs();
+  }
+
+  /**
+   * Watch for all existing and new tabs being opened.
+   * So that we can create the related TabTarget instance for
+   * each of them.
+   */
+  async watchForTabs() {
+    if (this.tabObserver) {
+      throw new Error("Targets is already watching for new tabs");
+    }
+
+    this.tabObserver = new lazy.TabObserver({ registerExisting: true });
+
+    // Handle creation of tab targets for opened tabs.
+    this.tabObserver.on("open", async (eventName, tab) => {
+      const target = new lazy.TabTarget(this, tab.linkedBrowser);
+      this.registerTarget(target);
+    });
+
+    // Handle removal of tab targets when tabs are closed.
+    this.tabObserver.on("close", (eventName, tab) => {
+      const browser = tab.linkedBrowser;
+
+      // Ignore unloaded tabs.
+      if (browser.browserId === 0) {
+        return;
+      }
+
+      const id = lazy.TabManager.getIdForBrowser(browser);
+      const target = Array.from(this._targets.values()).find(
+        target => target.id == id
+      );
+      if (target) {
+        this.destroyTarget(target);
+      }
+    });
+    await this.tabObserver.start();
+  }
+
+  unwatchForTabs() {
+    if (this.tabObserver) {
+      this.tabObserver.stop();
+      this.tabObserver = null;
+    }
+  }
+
+  /**
+   * To be called right after instantiating a new Target instance.
+   * This will hold the new instance in the list and notify about
+   * its creation.
+   */
+  registerTarget(target) {
+    this._targets.set(target.id, target);
+    this.emit("target-created", target);
+  }
+
+  /**
+   * To be called when the debuggable target has been destroy.
+   * So that we can notify it no longer exists and disconnect
+   * all connecting made to debug it.
+   */
+  destroyTarget(target) {
+    target.destructor();
+    this._targets.delete(target.id);
+    this.emit("target-destroyed", target);
+  }
+
+  /**
+   * Destroy all the registered target of all kinds.
+   * This will end up dropping all connections made to debug any of them.
+   */
+  destructor() {
+    for (const target of this) {
+      this.destroyTarget(target);
+    }
+    this._targets.clear();
+    if (this.mainProcessTarget) {
+      this.mainProcessTarget = null;
+    }
+
+    this.unwatchForTargets();
+  }
+
+  get size() {
+    return this._targets.size;
+  }
+
+  /**
+   * Get Target instance by target id
+   *
+   * @param {string} id
+   *     Target id
+   *
+   * @returns {Target}
+   */
+  getById(id) {
+    return this._targets.get(id);
+  }
+
+  /**
+   * Get the Target instance for the main process.
+   * This target is a singleton and only exposes a subset of domains.
+   */
+  getMainProcessTarget() {
+    if (!this.mainProcessTarget) {
+      this.mainProcessTarget = new lazy.MainProcessTarget(this);
+      this.registerTarget(this.mainProcessTarget);
+    }
+    return this.mainProcessTarget;
+  }
+
+  *[Symbol.iterator]() {
+    for (const target of this._targets.values()) {
+      yield target;
+    }
+  }
+
+  toJSON() {
+    return [...this];
+  }
+
+  toString() {
+    return `[object TargetList ${this.size}]`;
+  }
+}