Add a power saving mode setting

Create a setting that tunes performance optimizations and improves the
power usage.
Automatically tune mode with the Power-saving mode of Android Lollipop+.
Also, when the phone drops below threshold for low battery, prompt user
to turn browser's power save mode on.

Change-Id: I64089a371de562f9a18c297eb09555733f020515

10 files changed, 152 insertions, 1 deletions

diff --git a/res/values-zh-rCN/strings.xml b/res/values-zh-rCN/strings.xml
index d04560a8..ad0b7507 100644
--- a/res/values-zh-rCN/strings.xml
+++ b/res/values-zh-rCN/strings.xml
@@ -150,6 +150,8 @@
     <string name="pref_do_not_track">"不跟踪"</string>
     <string name="pref_do_not_track_summary">"随浏览流量发送"请勿跟踪"请求"</string>
     <string name="pref_sample_font_size">"拖动该滑块，将文字调整到适合您阅读的大小。点按两次某段落后，文字至少应该显示为这样的字体大小。"</string>
+    <string name="pref_powersave_enabled">"省电模式"</string>
+    <string name="pref_powersave_enabled_summary">"开启省电模式"</string>
 
   <string-array name="pref_content_plugins_choices">
     <item msgid="6745108155096660725">"始终启用（打开）"</item>
diff --git a/res/values-zh-rHK/strings.xml b/res/values-zh-rHK/strings.xml
index 57d90922..587921cb 100644
--- a/res/values-zh-rHK/strings.xml
+++ b/res/values-zh-rHK/strings.xml
@@ -145,7 +145,8 @@
     <string name="ssl_certificate">安全性憑證</string>
     <string name="ssl_certificate_is_valid">此憑證有效。</string>
     <string name="pref_memory_monitor">啟用記憶體監察器</string>
-
+    <string name="pref_powersave_enabled">"省電模式"</string>
+    <string name="pref_powersave_enabled_summary">"開啟省電模式"</string>
 
   <string-array name="pref_content_plugins_choices">
     <item msgid="6745108155096660725">"永遠開啟"</item>
diff --git a/res/values-zh-rTW/strings.xml b/res/values-zh-rTW/strings.xml
index 2fa98a52..3ff67087 100644
--- a/res/values-zh-rTW/strings.xml
+++ b/res/values-zh-rTW/strings.xml
@@ -136,6 +136,11 @@
     <string name="pref_content_javascript" msgid="4570972030299516843">"啟用 JavaScript"</string>
     <string name="pref_content_open_in_background" msgid="824123779725118663">"在背景中開啟"</string>
     <string name="pref_content_plugins" msgid="7231944644794301582">"啟用外掛程式"</string>
+
+    <!-- Custom Translations -->
+    <string name="pref_powersave_enabled">"省電模式"</string>
+    <string name="pref_powersave_enabled_summary">"開啟省電模式"</string>
+
   <string-array name="pref_content_plugins_choices">
     <item msgid="6745108155096660725">"永遠開啟"</item>
     <item msgid="2484126708670016519">"隨選"</item>
diff --git a/res/values/strings.xml b/res/values/strings.xml
index cc63a709..62b31d7e 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -380,6 +380,11 @@
     <!-- Settings category for autofill under general. [CHAR-LIMIT=50] -->
     <string name="pref_general_autofill_title">Auto-fill</string>
 
+    <!-- Checkbox setting for enabling/disabling power save mode feature -->
+    <string name ="pref_powersave_enabled">Power save mode</string>
+    <!-- Settings summary for the powersave feature. -->
+    <string name ="pref_powersave_enabled_summary">Turn on power saving mode</string>
+
     <!-- Checkbox setting for enabling/disabling the form AutoFill feature [CHAR-LIMIT=32] -->
     <string name="pref_autofill_enabled">Form auto-fill</string>
     <!-- Settings summary for the form AutoFill feature. [CHAR-LIMIT=none] -->
diff --git a/res/xml/general_preferences.xml b/res/xml/general_preferences.xml
index a1f2d256..d0bf5334 100644
--- a/res/xml/general_preferences.xml
+++ b/res/xml/general_preferences.xml
@@ -37,6 +37,12 @@
             android:title="@string/pref_lab_fullscreen" />
 
         <CheckBoxPreference
+            android:defaultValue="false"
+            android:key="powersave_enabled"
+            android:summary="@string/pref_powersave_enabled_summary"
+            android:title="@string/pref_powersave_enabled" />
+
+        <CheckBoxPreference
             android:key="autofill_enabled"
             android:title="@string/pref_autofill_enabled"
             android:summary="@string/pref_autofill_enabled_summary"
diff --git a/src/com/android/browser/BrowserSettings.java b/src/com/android/browser/BrowserSettings.java
index e3d1ee56..864315a2 100644
--- a/src/com/android/browser/BrowserSettings.java
+++ b/src/com/android/browser/BrowserSettings.java
@@ -774,6 +774,14 @@ public class BrowserSettings implements OnSharedPreferenceChangeListener,
         mPrefs.edit().putBoolean(PREF_AUTOFILL_ENABLED, value).apply();
     }
 
+    public boolean isPowerSaveModeEnabled() {
+        return mPrefs.getBoolean(PREF_POWERSAVE_ENABLED, false);
+    }
+
+    public void setPowerSaveModeEnabled(boolean value) {
+        mPrefs.edit().putBoolean(PREF_POWERSAVE_ENABLED, value).apply();
+    }
+
     // -----------------------------
     // getter/setters for debug_preferences.xml
     // -----------------------------
diff --git a/src/com/android/browser/Controller.java b/src/com/android/browser/Controller.java
index 353fea90..07f2d12c 100644
--- a/src/com/android/browser/Controller.java
+++ b/src/com/android/browser/Controller.java
@@ -1,6 +1,8 @@
 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
+ * Copyright (C) 2015 The Linux Foundation
+ *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
@@ -30,6 +32,7 @@ import android.content.ContentValues;
 import android.content.DialogInterface;
 import android.content.DialogInterface.OnCancelListener;
 import android.content.Intent;
+import android.content.IntentFilter;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
 import android.content.res.Configuration;
@@ -255,6 +258,8 @@ public class Controller
     private float mLevel = 0.0f;
     private WebView.HitTestResult mResult;
     private static Bitmap mBookmarkBitmap;
+    private PowerConnectionReceiver mLowPowerReceiver;
+    private PowerConnectionReceiver mPowerChangeReceiver;
 
     public Controller(Activity browser) {
         mActivity = browser;
@@ -398,6 +403,19 @@ public class Controller
                 && BrowserActivity.ACTION_SHOW_BOOKMARKS.equals(intent.getAction())) {
             bookmarksOrHistoryPicker(ComboViews.Bookmarks);
         }
+
+        mLowPowerReceiver = new PowerConnectionReceiver();
+        mPowerChangeReceiver = new PowerConnectionReceiver();
+
+        //always track the android framework's power save mode
+        IntentFilter filter = new IntentFilter();
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            // Power save mode only exists in Lollipop and above
+            filter.addAction("android.os.action.POWER_SAVE_MODE_CHANGED");
+        }
+        filter.addAction(Intent.ACTION_BATTERY_OKAY);
+        mActivity.registerReceiver(mPowerChangeReceiver, filter);
+
     }
 
     private static class PruneThumbnails implements Runnable {
@@ -748,6 +766,8 @@ public class Controller
 
         WebView.disablePlatformNotifications();
         NfcHandler.unregister(mActivity);
+
+        mActivity.unregisterReceiver(mLowPowerReceiver);
     }
 
     @Override
@@ -797,6 +817,8 @@ public class Controller
         if (current != null && current.hasCrashed) {
             current.replaceCrashView(current.getWebView(), current.getViewContainer());
         }
+
+        mActivity.registerReceiver(mLowPowerReceiver, new IntentFilter(Intent.ACTION_BATTERY_LOW));
     }
 
     private void releaseWakeLock() {
@@ -852,6 +874,8 @@ public class Controller
         mActivity.getContentResolver().unregisterContentObserver(mBookmarksObserver);
         // Destroy all the tabs
         mTabControl.destroy();
+        // Unregister receiver
+        mActivity.unregisterReceiver(mPowerChangeReceiver);
     }
 
     protected boolean isActivityPaused() {
diff --git a/src/com/android/browser/PowerConnectionReceiver.java b/src/com/android/browser/PowerConnectionReceiver.java
new file mode 100644
index 00000000..f68d3fc7
--- /dev/null
+++ b/src/com/android/browser/PowerConnectionReceiver.java
@@ -0,0 +1,60 @@
+/* Copyright (c) 2015, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *      * Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *      * Redistributions in binary form must reproduce the above
+ *      copyright notice, this list of conditions and the following
+ *      disclaimer in the documentation and/or other materials provided
+ *      with the distribution.
+ *      * Neither the name of The Linux Foundation nor the names of its
+ *      contributors may be used to endorse or promote products derived
+ *      from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.android.browser;
+
+import com.android.browser.preferences.GeneralPreferencesFragment;
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.app.DownloadManager;
+import android.content.ActivityNotFoundException;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.Uri;
+import android.os.Build;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.PowerManager;
+
+public class PowerConnectionReceiver extends BroadcastReceiver {
+    static final String POWER_MODE_TOGGLE = "android.os.action.POWER_SAVE_MODE_CHANGED";
+    static final String POWER_OKAY = Intent.ACTION_BATTERY_OKAY;
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        BrowserSettings settings = BrowserSettings.getInstance();
+        String action = intent.getAction();
+        if (POWER_MODE_TOGGLE.equals(action)) {
+            // This feature is only on android L+
+            PowerManager pm = (PowerManager) context.getSystemService(context.POWER_SERVICE);
+            settings.setPowerSaveModeEnabled(pm.isPowerSaveMode());
+        } else if (POWER_OKAY.equals(action)) {
+            settings.setPowerSaveModeEnabled(false);
+        } else {
+            if (settings.isPowerSaveModeEnabled())
+                return;
+            Bundle bundle = new Bundle();
+            bundle.putBoolean("LowPower", true);
+            BrowserPreferencesPage.startPreferenceFragmentExtraForResult((Activity) context, GeneralPreferencesFragment.class.getName(), bundle, 0);
+        }
+    }
+}
diff --git a/src/com/android/browser/PreferenceKeys.java b/src/com/android/browser/PreferenceKeys.java
index f6b37f5f..b0c384a7 100644
--- a/src/com/android/browser/PreferenceKeys.java
+++ b/src/com/android/browser/PreferenceKeys.java
@@ -60,6 +60,7 @@ public interface PreferenceKeys {
     static final String PREF_AUTOFILL_ENABLED = "autofill_enabled";
     static final String PREF_AUTOFILL_PROFILE = "autofill_profile";
     static final String PREF_HOMEPAGE = "homepage";
+    static final String PREF_POWERSAVE_ENABLED = "powersave_enabled";
     static final String PREF_SYNC_WITH_CHROME = "sync_with_chrome";
 
     // ----------------------
diff --git a/src/com/android/browser/preferences/GeneralPreferencesFragment.java b/src/com/android/browser/preferences/GeneralPreferencesFragment.java
index f481e730..8ab79a3b 100644
--- a/src/com/android/browser/preferences/GeneralPreferencesFragment.java
+++ b/src/com/android/browser/preferences/GeneralPreferencesFragment.java
@@ -93,6 +93,12 @@ public class GeneralPreferencesFragment extends PreferenceFragment
                 PreferenceKeys.PREF_AUTOFILL_PROFILE);
         autofill.setOnPreferenceClickListener(this);
 
+        final Bundle arguments = getArguments();
+        if (arguments != null && arguments.getBoolean("LowPower")) {
+            LowPowerDialogFragment fragment = LowPowerDialogFragment.newInstance();
+            fragment.show(getActivity().getFragmentManager(), "setPowersave dialog");
+        }
+
         //Disable set search engine preference if SEARCH_ENGINE restriction is enabled
         if (SearchEngineRestriction.getInstance().isEnabled()) {
             findPreference("search_engine").setEnabled(false);
@@ -301,4 +307,37 @@ public class GeneralPreferencesFragment extends PreferenceFragment
             outState.putString(HOME_PAGE, editText.getText().toString().trim());
         }
     }
+    public static class LowPowerDialogFragment extends DialogFragment {
+        public static LowPowerDialogFragment newInstance() {
+            LowPowerDialogFragment frag = new LowPowerDialogFragment();
+            return frag;
+        }
+
+        @Override
+        public Dialog onCreateDialog(Bundle savedInstanceState) {
+            final BrowserSettings settings = BrowserSettings.getInstance();
+            final AlertDialog dialog = new AlertDialog.Builder(getActivity())
+                    .setPositiveButton(android.R.string.ok, new OnClickListener() {
+                        @Override
+                        public void onClick(DialogInterface dialog, int which) {
+                            settings.setPowerSaveModeEnabled(true);
+                            getActivity().finish();
+                        }
+                    })
+                    .setNegativeButton(android.R.string.cancel, new OnClickListener() {
+                        @Override
+                        public void onClick(DialogInterface dialog, int which) {
+                            dialog.cancel();
+                            getActivity().finish();
+                        }
+                    })
+                    .setTitle(R.string.pref_powersave_enabled_summary)
+                    .create();
+
+            dialog.getWindow().setSoftInputMode(
+                    WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
+
+            return dialog;
+        }
+    }
 }