Split AM/PM from the rest of the time in expanded QS

This allows us to scale AM/PM independently of the rest of the time
string to allow for a different scale when QS is expanded.

Bug: 16177564
Change-Id: I472db549c875f6975583a6a426cb1ebc2fc37ac3
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/SplitClockView.java b/packages/SystemUI/src/com/android/systemui/statusbar/policy/SplitClockView.java
new file mode 100644
index 0000000..e7c4ede
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/SplitClockView.java
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * 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
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.systemui.statusbar.policy;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.text.format.DateFormat;
+import android.util.AttributeSet;
+import android.widget.LinearLayout;
+import android.widget.TextClock;
+
+import com.android.systemui.R;
+
+/**
+ * Container for a clock which has two separate views for the clock itself and AM/PM indicator. This
+ * is used to scale the clock independently of AM/PM.
+ */
+public class SplitClockView extends LinearLayout {
+
+    private TextClock mTimeView;
+    private TextClock mAmPmView;
+
+    private BroadcastReceiver mIntentReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            final String action = intent.getAction();
+            if (Intent.ACTION_TIME_CHANGED.equals(action)
+                    || Intent.ACTION_TIMEZONE_CHANGED.equals(action)
+                    || Intent.ACTION_LOCALE_CHANGED.equals(action)) {
+                updatePatterns();
+            }
+        }
+    };
+
+    public SplitClockView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    protected void onFinishInflate() {
+        super.onFinishInflate();
+        mTimeView = (TextClock) findViewById(R.id.time_view);
+        mAmPmView = (TextClock) findViewById(R.id.am_pm_view);
+    }
+
+    @Override
+    protected void onAttachedToWindow() {
+        super.onAttachedToWindow();
+
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(Intent.ACTION_TIME_CHANGED);
+        filter.addAction(Intent.ACTION_TIMEZONE_CHANGED);
+        filter.addAction(Intent.ACTION_LOCALE_CHANGED);
+        getContext().registerReceiver(mIntentReceiver, filter, null, null);
+
+        updatePatterns();
+    }
+
+    @Override
+    protected void onDetachedFromWindow() {
+        super.onDetachedFromWindow();
+        getContext().unregisterReceiver(mIntentReceiver);
+    }
+
+    private void updatePatterns() {
+        String formatString = DateFormat.getTimeFormatString(getContext());
+        int index = getAmPmPartEndIndex(formatString);
+        String timeString;
+        String amPmString;
+        if (index == -1) {
+            timeString = formatString;
+            amPmString = "";
+        } else {
+            timeString = formatString.substring(0, index);
+            amPmString = formatString.substring(index);
+        }
+        mTimeView.setFormat12Hour(timeString);
+        mTimeView.setFormat24Hour(timeString);
+        mAmPmView.setFormat12Hour(amPmString);
+        mAmPmView.setFormat24Hour(amPmString);
+    }
+
+    /**
+     * @return the index where the AM/PM part starts at the end in {@code formatString} including
+     *         leading white spaces or {@code -1} if no AM/PM part is found or {@code formatString}
+     *         doesn't end with AM/PM part
+     */
+    private static int getAmPmPartEndIndex(String formatString) {
+        boolean hasAmPm = false;
+        int length = formatString.length();
+        for (int i = length - 1; i >= 0; i--) {
+            char c = formatString.charAt(i);
+            boolean isAmPm = c == 'a';
+            boolean isWhitespace = Character.isWhitespace(c);
+            if (isAmPm) {
+                hasAmPm = true;
+            }
+            if (isAmPm || isWhitespace) {
+                continue;
+            }
+            if (i == length - 1) {
+
+                // First character was not AM/PM and not whitespace, so it's not ending with AM/PM.
+                return -1;
+            } else {
+
+                // If we have AM/PM at all, return last index, or -1 to indicate that it's not
+                // ending with AM/PM.
+                return hasAmPm ? i + 1 : -1;
+            }
+        }
+
+        // Only AM/PM and whitespaces? The whole string is AM/PM. Else: Only whitespaces in the
+        // string.
+        return hasAmPm ? 0 : -1;
+    }
+
+}