Introduce AbstractBluetoothA2dpPreferenceCtrl

- Refactor BluetoothAudioSampleRatePreferenceController into
  AbstractBluetoothA2dpPreferenceController
 - Make it easier to implement future bluetooth a2dp preferences

Bug: 34203528
Test: make RunSettingsRoboTests -j40
Change-Id: Ie94273c2b97504f4fb63f11b1afc21abc6944ffb

src/com/android/settings/development/AbstractBluetoothA2dpPreferenceController.java

@@ -0,0 +1,214 @@
+/*
+ * Copyright (C) 2017 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.development;
+
+import android.bluetooth.BluetoothA2dp;
+import android.bluetooth.BluetoothCodecConfig;
+import android.content.Context;
+import android.support.annotation.VisibleForTesting;
+import android.support.v7.preference.ListPreference;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceScreen;
+
+import com.android.settings.R;
+import com.android.settings.core.PreferenceControllerMixin;
+import com.android.settingslib.core.lifecycle.Lifecycle;
+import com.android.settingslib.core.lifecycle.LifecycleObserver;
+import com.android.settingslib.core.lifecycle.events.OnDestroy;
+import com.android.settingslib.development.DeveloperOptionsPreferenceController;
+
+public abstract class AbstractBluetoothA2dpPreferenceController extends
+        DeveloperOptionsPreferenceController implements Preference.OnPreferenceChangeListener,
+        PreferenceControllerMixin, BluetoothServiceConnectionListener, LifecycleObserver,
+        OnDestroy {
+
+    @VisibleForTesting
+    static final int STREAMING_LABEL_ID = R.string.bluetooth_select_a2dp_codec_streaming_label;
+
+    protected final BluetoothA2dpConfigStore mBluetoothA2dpConfigStore;
+    protected final Object mBluetoothA2dpLock;
+    protected BluetoothA2dp mBluetoothA2dp;
+    private final String[] mListValues;
+    private final String[] mListSummaries;
+    private ListPreference mPreference;
+
+    public AbstractBluetoothA2dpPreferenceController(Context context, Lifecycle lifecycle,
+            Object bluetoothA2dpLock, BluetoothA2dpConfigStore store) {
+        super(context);
+
+        mBluetoothA2dpLock = bluetoothA2dpLock;
+        mBluetoothA2dpConfigStore = store;
+        mListValues = getListValues();
+        mListSummaries = getListSummaries();
+
+        if (lifecycle != null) {
+            lifecycle.addObserver(this);
+        }
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+
+        mPreference = (ListPreference) screen.findPreference(getPreferenceKey());
+
+        // Set a default value because BluetoothCodecConfig is null initially.
+        mPreference.setValue(mListValues[getDefaultIndex()]);
+        mPreference.setSummary(mListSummaries[getDefaultIndex()]);
+    }
+
+    @Override
+    public boolean onPreferenceChange(Preference preference, Object newValue) {
+        if (mBluetoothA2dp == null) {
+            return false;
+        }
+
+        writeConfigurationValues(newValue);
+
+        final BluetoothCodecConfig codecConfig = mBluetoothA2dpConfigStore.createCodecConfig();
+        synchronized (mBluetoothA2dpLock) {
+            if (mBluetoothA2dp != null) {
+                setCodecConfigPreference(codecConfig);
+            }
+        }
+        // Because the setting is not persisted into permanent storage, we cannot call update state
+        // here to update the preference.
+        // Instead, we just assume it was set and update the preference here.
+        final int index = mPreference.findIndexOfValue(newValue.toString());
+        // We only want to append "Streaming" if not using default
+        if (index == getDefaultIndex()) {
+            mPreference.setSummary(mListSummaries[index]);
+        } else {
+            mPreference.setSummary(
+                    mContext.getResources().getString(STREAMING_LABEL_ID, mListSummaries[index]));
+        }
+        return true;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        if (getCodecConfig() == null || mPreference == null) {
+            return;
+        }
+
+        BluetoothCodecConfig codecConfig;
+        synchronized (mBluetoothA2dpLock) {
+            codecConfig = getCodecConfig();
+        }
+
+        final int index = getCurrentA2dpSettingIndex(codecConfig);
+        mPreference.setValue(mListValues[index]);
+
+        // We only want to append "Streaming" if not using default
+        if (index == getDefaultIndex()) {
+            mPreference.setSummary(mListSummaries[index]);
+        } else {
+            mPreference.setSummary(
+                    mContext.getResources().getString(STREAMING_LABEL_ID, mListSummaries[index]));
+        }
+
+        writeConfigurationValues(mListValues[index]);
+    }
+
+    @Override
+    public void onBluetoothServiceConnected(BluetoothA2dp bluetoothA2dp) {
+        mBluetoothA2dp = bluetoothA2dp;
+        updateState(mPreference);
+    }
+
+    @Override
+    public void onBluetoothCodecUpdated() {
+        // intentional no-op
+        // We do not want to call update state here because the setting is not persisted in
+        // permanent storage.
+    }
+
+    @Override
+    public void onBluetoothServiceDisconnected() {
+        mBluetoothA2dp = null;
+    }
+
+    @Override
+    public void onDestroy() {
+        mBluetoothA2dp = null;
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchEnabled() {
+        mPreference.setEnabled(true);
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchDisabled() {
+        mPreference.setEnabled(false);
+    }
+
+    /**
+     * @return an array of string values that correspond to the current {@link ListPreference}.
+     */
+    protected abstract String[] getListValues();
+
+    /**
+     * @return an array of string summaries that correspond to the current {@link ListPreference}.
+     */
+    protected abstract String[] getListSummaries();
+
+    /**
+     * Updates the new value to the {@link BluetoothA2dpConfigStore}.
+     *
+     * @param newValue the new setting value
+     */
+    protected abstract void writeConfigurationValues(Object newValue);
+
+    /**
+     * @return the current selected index for the {@link ListPreference}.
+     */
+    protected abstract int getCurrentA2dpSettingIndex(BluetoothCodecConfig config);
+
+    /**
+     * @return default setting index for the {@link ListPreference}.
+     */
+    protected abstract int getDefaultIndex();
+
+    @VisibleForTesting
+    void setCodecConfigPreference(BluetoothCodecConfig config) {
+        mBluetoothA2dp.setCodecConfigPreference(config);
+    }
+
+    @VisibleForTesting
+    BluetoothCodecConfig getCodecConfig() {
+        if (mBluetoothA2dp == null || mBluetoothA2dp.getCodecStatus() == null) {
+            return null;
+        }
+
+        return mBluetoothA2dp.getCodecStatus().getCodecConfig();
+    }
+
+    @VisibleForTesting
+    BluetoothCodecConfig createCodecConfig(int codecTypeValue, int codecPriorityValue,
+            int sampleRateValue, int bitsPerSampleValue,
+            int channelModeValue, long codecSpecific1Value,
+            long codecSpecific2Value, long codecSpecific3Value,
+            long codecSpecific4Value) {
+        return new BluetoothCodecConfig(codecTypeValue, codecPriorityValue,
+                sampleRateValue, bitsPerSampleValue,
+                channelModeValue, codecSpecific1Value,
+                codecSpecific2Value, codecSpecific3Value,
+                codecSpecific4Value);
+    }
+
+}