DO NOT MERGE Make "Want to start battery saver?" dialog better.

- Don't line-break in "Battery" (only in English)
- Add "Learn more" link.

Bug: 78261259

Test: Manual test with:
- adb shell dumpsys battery unplug
- adb shell settings delete secure low_power_warning_acknowledged
- Enable battery saver
- Make sure the link is clickable if a link is set.
- Make sure there's no "learn more" link if the link is not set in strings.xml

Change-Id: I83364f628dd596a4d50bf2aca4db7cbfe7cf4909
diff --git a/core/java/android/app/AlertDialog.java b/core/java/android/app/AlertDialog.java
index a44bd03..07b4b9c 100644
--- a/core/java/android/app/AlertDialog.java
+++ b/core/java/android/app/AlertDialog.java
@@ -16,8 +16,6 @@
 
 package android.app;
 
-import com.android.internal.app.AlertController;
-
 import android.annotation.ArrayRes;
 import android.annotation.AttrRes;
 import android.annotation.DrawableRes;
@@ -30,17 +28,19 @@
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.os.Message;
+import android.text.Layout;
+import android.text.method.MovementMethod;
 import android.util.TypedValue;
 import android.view.ContextThemeWrapper;
 import android.view.KeyEvent;
 import android.view.View;
-import android.view.WindowManager;
 import android.widget.AdapterView;
 import android.widget.Button;
 import android.widget.ListAdapter;
 import android.widget.ListView;
 
 import com.android.internal.R;
+import com.android.internal.app.AlertController;
 
 /**
  * A subclass of Dialog that can display one, two or three buttons. If you only want to
@@ -54,7 +54,7 @@
  * </pre>
  *
  * <p>The AlertDialog class takes care of automatically setting
- * {@link WindowManager.LayoutParams#FLAG_ALT_FOCUSABLE_IM
+ * {@link android.view.WindowManager.LayoutParams#FLAG_ALT_FOCUSABLE_IM
  * WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM} for you based on whether
  * any views in the dialog return true from {@link View#onCheckIsTextEditor()
  * View.onCheckIsTextEditor()}.  Generally you want this set for a Dialog
@@ -266,6 +266,17 @@
         mAlert.setMessage(message);
     }
 
+    /** @hide */
+    public void setMessageMovementMethod(MovementMethod movementMethod) {
+        mAlert.setMessageMovementMethod(movementMethod);
+    }
+
+    /** @hide */
+    public void setMessageHyphenationFrequency(
+            @Layout.HyphenationFrequency int hyphenationFrequency) {
+        mAlert.setMessageHyphenationFrequency(hyphenationFrequency);
+    }
+
     /**
      * Set the view to display in that dialog.
      */
diff --git a/core/java/com/android/internal/app/AlertController.java b/core/java/com/android/internal/app/AlertController.java
index 46cb546..7321721 100644
--- a/core/java/com/android/internal/app/AlertController.java
+++ b/core/java/com/android/internal/app/AlertController.java
@@ -30,7 +30,10 @@
 import android.graphics.drawable.Drawable;
 import android.os.Handler;
 import android.os.Message;
+import android.text.Layout;
 import android.text.TextUtils;
+import android.text.method.LinkMovementMethod;
+import android.text.method.MovementMethod;
 import android.util.AttributeSet;
 import android.util.TypedValue;
 import android.view.Gravity;
@@ -101,6 +104,9 @@
     private ImageView mIconView;
     private TextView mTitleView;
     protected TextView mMessageView;
+    private MovementMethod mMessageMovementMethod;
+    @Layout.HyphenationFrequency
+    private Integer mMessageHyphenationFrequency;
     private View mCustomTitleView;
 
     private boolean mForceInverseBackground;
@@ -290,6 +296,21 @@
         }
     }
 
+    public void setMessageMovementMethod(MovementMethod movementMethod) {
+        mMessageMovementMethod = movementMethod;
+        if (mMessageView != null) {
+            mMessageView.setMovementMethod(movementMethod);
+        }
+    }
+
+    public void setMessageHyphenationFrequency(
+            @Layout.HyphenationFrequency int hyphenationFrequency) {
+        mMessageHyphenationFrequency = hyphenationFrequency;
+        if (mMessageView != null) {
+            mMessageView.setHyphenationFrequency(hyphenationFrequency);
+        }
+    }
+
     /**
      * Set the view resource to display in the dialog.
      */
@@ -676,6 +697,12 @@
 
         if (mMessage != null) {
             mMessageView.setText(mMessage);
+            if (mMessageMovementMethod != null) {
+                mMessageView.setMovementMethod(mMessageMovementMethod);
+            }
+            if (mMessageHyphenationFrequency != null) {
+                mMessageView.setHyphenationFrequency(mMessageHyphenationFrequency);
+            }
         } else {
             mMessageView.setVisibility(View.GONE);
             mScrollView.removeView(mMessageView);
diff --git a/core/res/res/values/strings.xml b/core/res/res/values/strings.xml
index 395b269..e5bb587 100644
--- a/core/res/res/values/strings.xml
+++ b/core/res/res/values/strings.xml
@@ -4514,7 +4514,10 @@
     <!-- Notification shown when device owner silently deletes a package [CHAR LIMIT=NONE] -->
     <string name="package_deleted_device_owner">Deleted by your admin</string>
 
-    <!-- [CHAR_LIMIT=NONE] Battery saver: Feature description -->
+    <!-- [CHAR_LIMIT=NONE] Battery saver: Feature description, with a "learn more" link. -->
+    <string name="battery_saver_description_with_learn_more">To extend your battery life, Battery Saver turns off some device features and restricts apps. <annotation id="url">Learn More</annotation></string>
+
+    <!-- [CHAR_LIMIT=NONE] Battery saver: Feature description, without a "learn more" link. -->
     <string name="battery_saver_description">To extend your battery life, Battery Saver turns off some device features and restricts apps.</string>
 
     <!-- [CHAR_LIMIT=NONE] Data saver: Feature description -->
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 6721f93..2bb4476 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -3369,4 +3369,5 @@
   <java-symbol type="id" name="user_loading_avatar" />
   <java-symbol type="id" name="user_loading" />
 
+  <java-symbol type="string" name="battery_saver_description_with_learn_more" />
 </resources>
diff --git a/packages/SystemUI/res/values/strings.xml b/packages/SystemUI/res/values/strings.xml
index d82b00c..697ab06 100644
--- a/packages/SystemUI/res/values/strings.xml
+++ b/packages/SystemUI/res/values/strings.xml
@@ -2223,4 +2223,6 @@
     <!-- An action on the dialog that tells that scheduled (i.e. automatic) battery saver: user acknowledges and closes the dialog.  [CHAR LIMIT=NONE]-->
     <string name="auto_saver_okay_action">Got it</string>
 
+    <!-- URl of the webpage that explains battery saver. -->
+    <string name="help_uri_battery_saver_learn_more_link_target" translatable="false"></string>
 </resources>
diff --git a/packages/SystemUI/src/com/android/systemui/power/PowerNotificationWarnings.java b/packages/SystemUI/src/com/android/systemui/power/PowerNotificationWarnings.java
index d860fc5..c6bb17c 100644
--- a/packages/SystemUI/src/com/android/systemui/power/PowerNotificationWarnings.java
+++ b/packages/SystemUI/src/com/android/systemui/power/PowerNotificationWarnings.java
@@ -19,17 +19,29 @@
 import android.app.Notification;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
+import android.content.ActivityNotFoundException;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.media.AudioAttributes;
+import android.net.Uri;
 import android.os.Handler;
 import android.os.Looper;
 import android.os.PowerManager;
 import android.os.UserHandle;
 import android.support.annotation.VisibleForTesting;
+import android.text.Annotation;
+import android.text.Layout;
+import android.text.SpannableString;
+import android.text.SpannableStringBuilder;
+import android.text.TextPaint;
+import android.text.TextUtils;
+import android.text.method.LinkMovementMethod;
+import android.text.style.URLSpan;
+import android.util.Log;
 import android.util.Slog;
+import android.view.View;
 
 import com.android.internal.messages.nano.SystemMessageProto.SystemMessage;
 import com.android.settingslib.Utils;
@@ -42,6 +54,8 @@
 
 import java.io.PrintWriter;
 import java.text.NumberFormat;
+import java.util.Locale;
+import java.util.Objects;
 
 public class PowerNotificationWarnings implements PowerUI.WarningsUI {
     private static final String TAG = PowerUI.TAG + ".Notification";
@@ -87,6 +101,8 @@
     private static final String SETTINGS_ACTION_OPEN_BATTERY_SAVER_SETTING =
             "android.settings.BATTERY_SAVER_SETTINGS";
 
+    private static final String BATTERY_SAVER_DESCRIPTION_URL_KEY = "url";
+
     private static final AudioAttributes AUDIO_ATTRIBUTES = new AudioAttributes.Builder()
             .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
             .setUsage(AudioAttributes.USAGE_ASSISTANCE_SONIFICATION)
@@ -461,7 +477,16 @@
         if (mSaverConfirmation != null) return;
         final SystemUIDialog d = new SystemUIDialog(mContext);
         d.setTitle(R.string.battery_saver_confirmation_title);
-        d.setMessage(com.android.internal.R.string.battery_saver_description);
+        d.setMessage(getBatterySaverDescription());
+
+        // Sad hack for http://b/78261259 and http://b/78298335. Otherwise "Battery" may be split
+        // into "Bat-tery".
+        if (isEnglishLocale()) {
+            d.setMessageHyphenationFrequency(Layout.HYPHENATION_FREQUENCY_NONE);
+        }
+        // We need to set LinkMovementMethod to make the link clickable.
+        d.setMessageMovementMethod(LinkMovementMethod.getInstance());
+
         d.setNegativeButton(android.R.string.cancel, null);
         d.setPositiveButton(R.string.battery_saver_confirmation_ok,
                 (dialog, which) -> setSaverMode(true, false));
@@ -471,6 +496,79 @@
         mSaverConfirmation = d;
     }
 
+    private boolean isEnglishLocale() {
+        return Objects.equals(Locale.getDefault().getLanguage(),
+                Locale.ENGLISH.getLanguage());
+    }
+
+    /**
+     * Generates the message for the "want to start battery saver?" dialog with a "learn more" link.
+     */
+    private CharSequence getBatterySaverDescription() {
+        final String learnMoreUrl = mContext.getText(
+                R.string.help_uri_battery_saver_learn_more_link_target).toString();
+
+        // If there's no link, use the string with no "learn more".
+        if (TextUtils.isEmpty(learnMoreUrl)) {
+            return mContext.getText(
+                    com.android.internal.R.string.battery_saver_description);
+        }
+
+        // If we have a link, use the string with the "learn more" link.
+        final CharSequence rawText = mContext.getText(
+                com.android.internal.R.string.battery_saver_description_with_learn_more);
+        final SpannableString message = new SpannableString(rawText);
+        final SpannableStringBuilder builder = new SpannableStringBuilder(message);
+
+        // Look for the "learn more" part of the string, and set a URL span on it.
+        // We use a customized URLSpan to add FLAG_RECEIVER_FOREGROUND to the intent, and
+        // also to close the dialog.
+        for (Annotation annotation : message.getSpans(0, message.length(), Annotation.class)) {
+            final String key = annotation.getValue();
+
+            if (!BATTERY_SAVER_DESCRIPTION_URL_KEY.equals(key)) {
+                continue;
+            }
+            final int start = message.getSpanStart(annotation);
+            final int end = message.getSpanEnd(annotation);
+
+            // Replace the "learn more" with a custom URL span, with
+            // - No underline.
+            // - When clicked, close the dialog and the notification shade.
+            final URLSpan urlSpan = new URLSpan(learnMoreUrl) {
+                @Override
+                public void updateDrawState(TextPaint ds) {
+                    super.updateDrawState(ds);
+                    ds.setUnderlineText(false);
+                }
+
+                @Override
+                public void onClick(View widget) {
+                    // Close the parent dialog.
+                    if (mSaverConfirmation != null) {
+                        mSaverConfirmation.dismiss();
+                    }
+                    // Also close the notification shade, if it's open.
+                    mContext.sendBroadcast(
+                            new Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)
+                            .setFlags(Intent.FLAG_RECEIVER_FOREGROUND));
+
+                    final Uri uri = Uri.parse(getURL());
+                    Context context = widget.getContext();
+                    Intent intent = new Intent(Intent.ACTION_VIEW, uri)
+                            .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                    try {
+                        context.startActivity(intent);
+                    } catch (ActivityNotFoundException e) {
+                        Log.w(TAG, "Activity was not found for intent, " + intent.toString());
+                    }
+                }
+            };
+            builder.setSpan(urlSpan, start, end, message.getSpanFlags(urlSpan));
+        }
+        return builder;
+    }
+
     private void showAutoSaverEnabledConfirmation() {
         if (mSaverEnabledConfirmation != null) return;