Add timestamp to infobar for stale Previews

chrome/browser/previews/previews_infobar_delegate.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/previews/previews_infobar_delegate.h"
 
+#include "base/feature_list.h"
+#include "base/metrics/field_trial_params.h"
 #include "base/metrics/histogram.h"
 #include "base/optional.h"
+#include "base/strings/string16.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/android/android_theme_resources.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/infobars/infobar_service.h"
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings.h"
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings_factory.h"
 #include "chrome/browser/previews/previews_infobar_tab_helper.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_service.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/infobars/core/infobar.h"
+#include "components/network_time/network_time_tracker.h"
+#include "components/previews/core/previews_features.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_ANDROID)
 #include "chrome/browser/ui/android/infobars/previews_infobar.h"
 #endif
 
 namespace {
 
@@ skipping 65 matching lines @@
   if (!on_dismiss_callback_.is_null())
     on_dismiss_callback_.Run(false);
 
   RecordPreviewsInfoBarAction(previews_type_, infobar_dismissed_action_);
 }
 
 // static
 void PreviewsInfoBarDelegate::Create(
     content::WebContents* web_contents,
     previews::PreviewsType previews_type,
+    base::Time previews_freshness,
     bool is_data_saver_user,
     const OnDismissPreviewsInfobarCallback& on_dismiss_callback) {
   PreviewsInfoBarTabHelper* infobar_tab_helper =
       PreviewsInfoBarTabHelper::FromWebContents(web_contents);
   InfoBarService* infobar_service =
       InfoBarService::FromWebContents(web_contents);
 
   // The WebContents may not have TabHelpers set. If TabHelpers are not set,
   // don't show Previews infobars.
   if (!infobar_tab_helper || !infobar_service)
     return;
   if (infobar_tab_helper->displayed_preview_infobar())
     return;
 
   std::unique_ptr<PreviewsInfoBarDelegate> delegate(new PreviewsInfoBarDelegate(
-      web_contents, previews_type, is_data_saver_user, on_dismiss_callback));
+      web_contents, previews_type, previews_freshness, is_data_saver_user,
+      on_dismiss_callback));
 
 #if defined(OS_ANDROID)
   std::unique_ptr<infobars::InfoBar> infobar_ptr(
       PreviewsInfoBar::CreateInfoBar(infobar_service, std::move(delegate)));
 #else
   std::unique_ptr<infobars::InfoBar> infobar_ptr(
       infobar_service->CreateConfirmInfoBar(std::move(delegate)));
 #endif
 
   infobars::InfoBar* infobar =
       infobar_service->AddInfoBar(std::move(infobar_ptr));
 
   if (infobar && (previews_type == previews::PreviewsType::LITE_PAGE ||
                   previews_type == previews::PreviewsType::LOFI)) {
     auto* data_reduction_proxy_settings =
         DataReductionProxyChromeSettingsFactory::GetForBrowserContext(
             web_contents->GetBrowserContext());
     data_reduction_proxy_settings->IncrementLoFiUIShown();
   }
 
   RecordPreviewsInfoBarAction(previews_type, INFOBAR_SHOWN);
   infobar_tab_helper->set_displayed_preview_infobar(true);
 }
 
 PreviewsInfoBarDelegate::PreviewsInfoBarDelegate(
     content::WebContents* web_contents,
     previews::PreviewsType previews_type,
+    base::Time previews_freshness,
     bool is_data_saver_user,
     const OnDismissPreviewsInfobarCallback& on_dismiss_callback)
     : ConfirmInfoBarDelegate(),
       previews_type_(previews_type),
+      previews_freshness_(previews_freshness),
       infobar_dismissed_action_(INFOBAR_DISMISSED_BY_TAB_CLOSURE),
       message_text_(l10n_util::GetStringUTF16(
           is_data_saver_user ? IDS_PREVIEWS_INFOBAR_SAVED_DATA_TITLE
                              : IDS_PREVIEWS_INFOBAR_FASTER_PAGE_TITLE)),
       on_dismiss_callback_(on_dismiss_callback) {}
 
 infobars::InfoBarDelegate::InfoBarIdentifier
 PreviewsInfoBarDelegate::GetIdentifier() const {
   return DATA_REDUCTION_PROXY_PREVIEW_INFOBAR_DELEGATE;
 }
@@ skipping 12 matching lines @@
                                   ? INFOBAR_DISMISSED_BY_RELOAD
                                   : INFOBAR_DISMISSED_BY_NAVIGATION;
   return InfoBarDelegate::ShouldExpire(details);
 }
 
 void PreviewsInfoBarDelegate::InfoBarDismissed() {
   infobar_dismissed_action_ = INFOBAR_DISMISSED_BY_USER;
 }
 
 base::string16 PreviewsInfoBarDelegate::GetMessageText() const {
+// Android has a custom infobar that calls GetTimestampText() and adds the
+// timestamp in a separate description view. Other OS's can enable previews
+// for debugging purposes and don't have a custom infobar with a description
+// view, so the timestamp should be appended to the message.
+#if defined(OS_ANDROID)
   return message_text_;
+#else
+  base::string16 timestamp = GetTimestampText();
+  if (timestamp.empty())
+    return message_text_;
+  return message_text_ + base::ASCIIToUTF16(" ") + timestamp;
+#endif
 }
 
 int PreviewsInfoBarDelegate::GetButtons() const {
   return BUTTON_NONE;
 }
 
 base::string16 PreviewsInfoBarDelegate::GetLinkText() const {
   return l10n_util::GetStringUTF16(IDS_PREVIEWS_INFOBAR_LINK);
 }
 
@@ skipping 13 matching lines @@
       !data_reduction_proxy::params::IsBlackListEnabledForServerPreviews()) {
     IncrementDataReductionProxyPrefs(web_contents);
   }
 
   ReloadWithoutPreviews(previews_type_, web_contents);
 
   return true;
 }
 
 base::string16 PreviewsInfoBarDelegate::GetTimestampText() const {
-  return base::string16();
+  if (previews_freshness_.is_null())
+    return base::string16();
+  if (!base::FeatureList::IsEnabled(
+          previews::features::kStalePreviewsTimestamp)) {
+    return base::string16();
+  }
+
+  int min_staleness_in_minutes = base::GetFieldTrialParamByFeatureAsInt(
+      previews::features::kStalePreviewsTimestamp, "min_staleness_in_minutes",
+      0);
+  int max_staleness_in_minutes = base::GetFieldTrialParamByFeatureAsInt(
+      previews::features::kStalePreviewsTimestamp, "max_staleness_in_minutes",
+      0);
+
+  if (min_staleness_in_minutes == 0 || max_staleness_in_minutes == 0)
+    return base::string16();
+
+  base::Time network_time;
+  if (g_browser_process->network_time_tracker()->GetNetworkTime(&network_time,
+                                                                nullptr) !=
+      network_time::NetworkTimeTracker::NETWORK_TIME_AVAILABLE) {
+    // When network time has not been initialized yet, simply rely on the
+    // machine's current time.
+    network_time = base::Time::Now();
+  }
+
+  int staleness_in_minutes = (network_time - previews_freshness_).InMinutes();
+  // TODO(megjablon): record metrics for out of bounds staleness.
+  if (staleness_in_minutes < min_staleness_in_minutes)
+    return base::string16();
+  if (staleness_in_minutes > max_staleness_in_minutes)
+    return base::string16();
+
+  if (staleness_in_minutes < 60) {
+    return l10n_util::GetStringFUTF16(
+        IDS_PREVIEWS_INFOBAR_TIMESTAMP_MINUTES,
+        base::IntToString16(staleness_in_minutes));
+  } else if (staleness_in_minutes < 120) {
+    return l10n_util::GetStringUTF16(IDS_PREVIEWS_INFOBAR_TIMESTAMP_ONE_HOUR);
+  } else {
+    return l10n_util::GetStringFUTF16(
+        IDS_PREVIEWS_INFOBAR_TIMESTAMP_HOURS,
+        base::IntToString16(staleness_in_minutes / 60));
+  }
 }