1 files changed, 206 insertions, 0 deletions
diff --git a/mobile/android/components/geckoview/GeckoViewPrompter.sys.mjs b/mobile/android/components/geckoview/GeckoViewPrompter.sys.mjs
new file mode 100644
index 0000000000..f81c155678
--- /dev/null
+++ b/mobile/android/components/geckoview/GeckoViewPrompter.sys.mjs
@@ -0,0 +1,206 @@
+/* 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 { GeckoViewUtils } from "resource://gre/modules/GeckoViewUtils.sys.mjs";
+
+const { debug, warn } = GeckoViewUtils.initLogging("GeckoViewPrompter");
+
+export class GeckoViewPrompter {
+  constructor(aParent) {
+    this.id = Services.uuid.generateUUID().toString().slice(1, -1); // Discard surrounding braces
+
+    if (aParent) {
+      if (Window.isInstance(aParent)) {
+        this._domWin = aParent;
+      } else if (aParent.window) {
+        this._domWin = aParent.window;
+      } else {
+        this._domWin =
+          aParent.embedderElement && aParent.embedderElement.ownerGlobal;
+      }
+    }
+
+    if (!this._domWin) {
+      this._domWin = Services.wm.getMostRecentWindow("navigator:geckoview");
+    }
+
+    this._innerWindowId =
+      this._domWin?.browsingContext.currentWindowContext.innerWindowId;
+  }
+
+  get domWin() {
+    return this._domWin;
+  }
+
+  get prompterActor() {
+    const actor = this.domWin?.windowGlobalChild.getActor("GeckoViewPrompter");
+    return actor;
+  }
+
+  _changeModalState(aEntering) {
+    if (!this._domWin) {
+      // Allow not having a DOM window.
+      return true;
+    }
+    // Accessing the document object can throw if this window no longer exists. See bug 789888.
+    try {
+      const winUtils = this._domWin.windowUtils;
+      if (!aEntering) {
+        winUtils.leaveModalState();
+      }
+
+      const event = this._domWin.document.createEvent("Events");
+      event.initEvent(
+        aEntering ? "DOMWillOpenModalDialog" : "DOMModalDialogClosed",
+        true,
+        true
+      );
+      winUtils.dispatchEventToChromeOnly(this._domWin, event);
+
+      if (aEntering) {
+        winUtils.enterModalState();
+      }
+      return true;
+    } catch (ex) {
+      console.error("Failed to change modal state:", ex);
+    }
+    return false;
+  }
+
+  _dismissUi() {
+    this.prompterActor?.dismissPrompt(this);
+  }
+
+  accept(aInputText = this.inputText) {
+    if (this.callback) {
+      let acceptMsg = {};
+      switch (this.message.type) {
+        case "alert":
+          acceptMsg = null;
+          break;
+        case "button":
+          acceptMsg.button = 0;
+          break;
+        case "text":
+          acceptMsg.text = aInputText;
+          break;
+        default:
+          acceptMsg = null;
+          break;
+      }
+      this.callback(acceptMsg);
+      // Notify the UI that this prompt should be hidden.
+      this._dismissUi();
+    }
+  }
+
+  dismiss() {
+    this.callback(null);
+    // Notify the UI that this prompt should be hidden.
+    this._dismissUi();
+  }
+
+  getPromptType() {
+    switch (this.message.type) {
+      case "alert":
+        return this.message.checkValue ? "alertCheck" : "alert";
+      case "button":
+        return this.message.checkValue ? "confirmCheck" : "confirm";
+      case "text":
+        return this.message.checkValue ? "promptCheck" : "prompt";
+      default:
+        return this.message.type;
+    }
+  }
+
+  getPromptText() {
+    return this.message.msg;
+  }
+
+  getInputText() {
+    return this.inputText;
+  }
+
+  setInputText(aInput) {
+    this.inputText = aInput;
+  }
+
+  /**
+   * Shows a native prompt, and then spins the event loop for this thread while we wait
+   * for a response
+   */
+  showPrompt(aMsg) {
+    let result = undefined;
+    if (!this._domWin || !this._changeModalState(/* aEntering */ true)) {
+      return result;
+    }
+    try {
+      this.asyncShowPrompt(aMsg, res => (result = res));
+
+      // Spin this thread while we wait for a result
+      Services.tm.spinEventLoopUntil(
+        "GeckoViewPrompter.jsm:showPrompt",
+        () => this._domWin.closed || result !== undefined
+      );
+    } finally {
+      this._changeModalState(/* aEntering */ false);
+    }
+    return result;
+  }
+
+  checkInnerWindow() {
+    // Checks that the innerWindow where this prompt was created still matches
+    // the current innerWindow.
+    // This checks will fail if the page navigates away, making this prompt
+    // obsolete.
+    return (
+      this._innerWindowId ===
+      this._domWin.browsingContext.currentWindowContext.innerWindowId
+    );
+  }
+
+  asyncShowPromptPromise(aMsg) {
+    return new Promise(resolve => {
+      this.asyncShowPrompt(aMsg, resolve);
+    });
+  }
+
+  async asyncShowPrompt(aMsg, aCallback) {
+    this.message = aMsg;
+    this.inputText = aMsg.value;
+    this.callback = aCallback;
+
+    aMsg.id = this.id;
+
+    let response = null;
+    try {
+      if (this.checkInnerWindow()) {
+        response = await this.prompterActor.prompt(this, aMsg);
+      }
+    } catch (error) {
+      // Nothing we can do really, we will treat this as a dismiss.
+      warn`Error while prompting: ${error}`;
+    }
+
+    if (!this.checkInnerWindow()) {
+      // Page has navigated away, let's dismiss the prompt
+      aCallback(null);
+    } else {
+      aCallback(response);
+    }
+    // This callback object is tied to the Java garbage collector because
+    // it is invoked from Java. Manually release the target callback
+    // here; otherwise we may hold onto resources for too long, because
+    // we would be relying on both the Java and the JS garbage collectors
+    // to run.
+    aMsg = undefined;
+    aCallback = undefined;
+  }
+
+  update(aMsg) {
+    this.message = aMsg;
+    aMsg.id = this.id;
+    this.prompterActor?.updatePrompt(aMsg);
+  }
+}