From 8d5ce77f5d7efe6959ad4aedd4cd02f4f9df4462 Mon Sep 17 00:00:00 2001
From: Yuxuan Zhou <zhouyx@users.noreply.github.com>
Date: Fri, 7 Oct 2016 11:13:30 -0700
Subject: [PATCH] ALP for A4A (#5430)

---
 ads/alp/handler.js                  | 13 ++++++++++---
 build-system/dep-check-config.js    |  3 +++
 extensions/amp-a4a/0.1/amp-a4a.js   | 16 +++++++++++++++-
 test/functional/test-alp-handler.js | 15 +++++++++++++++
 tools/experiments/experiments.js    |  5 +++++
 5 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/ads/alp/handler.js b/ads/alp/handler.js
index a6d5b31fa71b0..fc8753dfa5ca3 100644
--- a/ads/alp/handler.js
+++ b/ads/alp/handler.js
@@ -52,9 +52,10 @@ export function installAlpClickHandler(win) {
  * Filter click event and then transform URL for direct AMP navigation
  * with impression logging.
  * @param {!Event} e
+ * @param {function(string)=} opt_viewerNavigate
  * @visibleForTesting
  */
-export function handleClick(e) {
+export function handleClick(e, opt_viewerNavigate) {
   if (e.defaultPrevented) {
     return;
   }
@@ -91,9 +92,15 @@ export function handleClick(e) {
     destination = destination.replace(`${urls.cdn}/c/`,
         'http://localhost:8000/max/');
   }
-
   e.preventDefault();
-  navigateTo(win, link.a, destination);
+  if (opt_viewerNavigate) {
+    // TODO: viewer navigate only support navigating top level window to
+    // destination. should we try to open a new window here with target=_blank
+    // here instead of using viewer navigation.
+    opt_viewerNavigate(destination);
+  } else {
+    navigateTo(win, link.a, destination);
+  }
 }
 
 /**
diff --git a/build-system/dep-check-config.js b/build-system/dep-check-config.js
index 33752aa1d49a4..56d1ed7546764 100644
--- a/build-system/dep-check-config.js
+++ b/build-system/dep-check-config.js
@@ -90,6 +90,9 @@ exports.rules = [
       'ads/google/a4a/**->src/timer.js',
       'ads/google/a4a/**->src/viewer.js',
       'ads/google/a4a/**->src/viewport.js',
+      // alp handler needs to depend on src files
+      'ads/alp/handler.js->src/dom.js',
+      'ads/alp/handler.js->src/config.js',
     ],
   },
   {
diff --git a/extensions/amp-a4a/0.1/amp-a4a.js b/extensions/amp-a4a/0.1/amp-a4a.js
index 481f92d164099..1a918a91d5148 100644
--- a/extensions/amp-a4a/0.1/amp-a4a.js
+++ b/extensions/amp-a4a/0.1/amp-a4a.js
@@ -39,6 +39,8 @@ import {
   verifySignature,
   PublicKeyInfoDef,
 } from './crypto-verifier';
+import {isExperimentOn} from '../../../src/experiments';
+import {handleClick} from '../../../ads/alp/handler';
 
 /**
  * Dev public key set. This will go away once the dev signing service goes live.
@@ -665,7 +667,8 @@ export class AmpA4A extends AMP.BaseElement {
               html: modifiedCreative,
               extensionIds: creativeMetaData.customElementExtensions || [],
               fonts: fontsArray,
-            }).then(() => {
+            }).then(friendlyIframeEmbed => {
+              this.registerAlpHandler_(friendlyIframeEmbed.win);
               this.rendered_ = true;
               this.onAmpCreativeRender();
               return true;
@@ -831,4 +834,15 @@ export class AmpA4A extends AMP.BaseElement {
        metaData.cssUtf16CharOffsets[0],
        metaData.cssUtf16CharOffsets[1]);
  }
+
+  registerAlpHandler_(iframeWin) {
+    if (!isExperimentOn(this.win, 'alp-for-a4a')) {
+      return;
+    }
+    iframeWin.document.documentElement.addEventListener('click', event => {
+      handleClick(event, url => {
+        viewerForDoc(this.getAmpDoc()).navigateTo(url, 'a4a');
+      });
+    });
+  }
 }
diff --git a/test/functional/test-alp-handler.js b/test/functional/test-alp-handler.js
index 7ed40659d79c2..0c4a4a032bc2e 100644
--- a/test/functional/test-alp-handler.js
+++ b/test/functional/test-alp-handler.js
@@ -192,6 +192,21 @@ describe('alp-handler', () => {
     simpleSuccess();
   });
 
+  it('should perform special navigation if specially asked for', () => {
+    const navigateSpy = sandbox.spy();
+    const opt_navigate = val => {
+      navigateSpy();
+      expect(val).to.equal(
+          'https://cdn.ampproject.org/c/www.example.com/amp.html#click=' +
+          'https%3A%2F%2Ftest.com%3Famp%3D1%26adurl%3Dhttps%253A%252F%252F' +
+          'cdn.ampproject.org%252Fc%252Fwww.example.com%252Famp.html');
+    };
+    handleClick(event, opt_navigate);
+    expect(event.preventDefault).to.be.calledOnce;
+    expect(open).to.not.be.called;
+    expect(navigateSpy).to.be.calledOnce;
+  });
+
   it('should navigate if trusted is not set.', () => {
     delete event.trusted;
     simpleSuccess();
diff --git a/tools/experiments/experiments.js b/tools/experiments/experiments.js
index b793f75ebf2bf..91ecc4fa0adfe 100644
--- a/tools/experiments/experiments.js
+++ b/tools/experiments/experiments.js
@@ -189,6 +189,11 @@ const EXPERIMENTS = [
     spec: 'https://github.com/ampproject/amphtml/issues/4820',
     cleanupIssue: 'https://github.com/ampproject/amphtml/issues/4894',
   },
+  {
+    id: 'alp-for-a4a',
+    name: 'Enable redirect to landing page directly for A4A',
+    spec: 'https://github.com/ampproject/amphtml/issues/5212',
+  },
 ];
 
 if (getMode().localDev) {