Refactor time format preference to be more modular/testable

Change-Id: Ib6c06de9f942c3bb06384947f6b1923b33e511bc
Fixes: 32972964
Test: make RunSettingsRoboTests
diff --git a/src/com/android/settings/datetime/TimeFormatPreferenceController.java b/src/com/android/settings/datetime/TimeFormatPreferenceController.java
new file mode 100644
index 0000000..068b790
--- /dev/null
+++ b/src/com/android/settings/datetime/TimeFormatPreferenceController.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2016 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.settings.datetime;
+
+import android.content.Context;
+import android.content.Intent;
+import android.provider.Settings;
+import android.support.v14.preference.SwitchPreference;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.TwoStatePreference;
+import android.text.TextUtils;
+import android.text.format.DateFormat;
+
+import com.android.settings.core.PreferenceController;
+
+import java.util.Calendar;
+import java.util.Date;
+
+public class TimeFormatPreferenceController extends PreferenceController {
+
+    static final String HOURS_12 = "12";
+    static final String HOURS_24 = "24";
+
+    private static final String KEY_TIME_FORMAT = "24 hour";
+
+    // Used for showing the current date format, which looks like "12/31/2010", "2010/12/13", etc.
+    // The date value is dummy (independent of actual date).
+    private final Calendar mDummyDate;
+    private final boolean mIsFromSUW;
+    private final UpdateTimeAndDateCallback mUpdateTimeAndDateCallback;
+
+    public TimeFormatPreferenceController(Context context, UpdateTimeAndDateCallback callback,
+            boolean isFromSUW) {
+        super(context);
+        mIsFromSUW = isFromSUW;
+        mDummyDate = Calendar.getInstance();
+        mUpdateTimeAndDateCallback = callback;
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return !mIsFromSUW;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        if (!(preference instanceof TwoStatePreference)
+                || !TextUtils.equals(KEY_TIME_FORMAT, preference.getKey())) {
+            return;
+        }
+        ((TwoStatePreference) preference).setChecked(is24Hour());
+        final Calendar now = Calendar.getInstance();
+        mDummyDate.setTimeZone(now.getTimeZone());
+        // We use December 31st because it's unambiguous when demonstrating the date format.
+        // We use 13:00 so we can demonstrate the 12/24 hour options.
+        mDummyDate.set(now.get(Calendar.YEAR), 11, 31, 13, 0, 0);
+        final Date dummyDate = mDummyDate.getTime();
+        preference.setSummary(DateFormat.getTimeFormat(mContext).format(dummyDate));
+    }
+
+    @Override
+    public boolean handlePreferenceTreeClick(Preference preference) {
+        if (!(preference instanceof TwoStatePreference)
+                || !TextUtils.equals(KEY_TIME_FORMAT, preference.getKey())) {
+            return false;
+        }
+        final boolean is24Hour = ((SwitchPreference) preference).isChecked();
+        set24Hour(is24Hour);
+        timeUpdated(is24Hour);
+        mUpdateTimeAndDateCallback.updateTimeAndDateDisplay(mContext);
+        return true;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_TIME_FORMAT;
+    }
+
+    private boolean is24Hour() {
+        return DateFormat.is24HourFormat(mContext);
+    }
+
+    private void timeUpdated(boolean is24Hour) {
+        Intent timeChanged = new Intent(Intent.ACTION_TIME_CHANGED);
+        timeChanged.putExtra(Intent.EXTRA_TIME_PREF_24_HOUR_FORMAT, is24Hour);
+        mContext.sendBroadcast(timeChanged);
+    }
+
+    private void set24Hour(boolean is24Hour) {
+        Settings.System.putString(mContext.getContentResolver(),
+                Settings.System.TIME_12_24,
+                is24Hour ? HOURS_24 : HOURS_12);
+    }
+}
diff --git a/src/com/android/settings/datetime/UpdateTimeAndDateCallback.java b/src/com/android/settings/datetime/UpdateTimeAndDateCallback.java
new file mode 100644
index 0000000..e89b5da
--- /dev/null
+++ b/src/com/android/settings/datetime/UpdateTimeAndDateCallback.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2016 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.settings.datetime;
+
+import android.content.Context;
+
+public interface UpdateTimeAndDateCallback {
+
+    void updateTimeAndDateDisplay(Context context);
+}