/*
 * 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 android.bluetooth;

import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.os.RemoteException;
import android.util.Log;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

/**
 * Public API to control Hands Free Profile (HFP role only).
 * <p>
 * This class defines methods that shall be used by application to manage profile
 * connection, calls states and calls actions.
 * <p>
 *
 * @hide
 * */
public final class BluetoothHeadsetClient implements BluetoothProfile {
    private static final String TAG = "BluetoothHeadsetClient";
    private static final boolean DBG = true;
    private static final boolean VDBG = false;

    /**
     * Intent sent whenever connection to remote changes.
     *
     * <p>It includes two extras:
     * <code>BluetoothProfile.EXTRA_PREVIOUS_STATE</code>
     * and <code>BluetoothProfile.EXTRA_STATE</code>, which
     * are mandatory.
     * <p>There are also non mandatory feature extras:
     * {@link #EXTRA_AG_FEATURE_3WAY_CALLING},
     * {@link #EXTRA_AG_FEATURE_VOICE_RECOGNITION},
     * {@link #EXTRA_AG_FEATURE_ATTACH_NUMBER_TO_VT},
     * {@link #EXTRA_AG_FEATURE_REJECT_CALL},
     * {@link #EXTRA_AG_FEATURE_ECC},
     * {@link #EXTRA_AG_FEATURE_RESPONSE_AND_HOLD},
     * {@link #EXTRA_AG_FEATURE_ACCEPT_HELD_OR_WAITING_CALL},
     * {@link #EXTRA_AG_FEATURE_RELEASE_HELD_OR_WAITING_CALL},
     * {@link #EXTRA_AG_FEATURE_RELEASE_AND_ACCEPT},
     * {@link #EXTRA_AG_FEATURE_MERGE},
     * {@link #EXTRA_AG_FEATURE_MERGE_AND_DETACH},
     * sent as boolean values only when <code>EXTRA_STATE</code>
     * is set to <code>STATE_CONNECTED</code>.</p>
     *
     * <p>Note that features supported by AG are being sent as
     * booleans with value <code>true</code>,
     * and not supported ones are <strong>not</strong> being sent at all.</p>
     */
    public static final String ACTION_CONNECTION_STATE_CHANGED =
        "android.bluetooth.headsetclient.profile.action.CONNECTION_STATE_CHANGED";

    /**
     * Intent sent whenever audio state changes.
     *
     * <p>It includes two mandatory extras:
     * {@link BluetoothProfile.EXTRA_STATE},
     * {@link BluetoothProfile.EXTRA_PREVIOUS_STATE},
     * with possible values:
     * {@link #STATE_AUDIO_CONNECTING},
     * {@link #STATE_AUDIO_CONNECTED},
     * {@link #STATE_AUDIO_DISCONNECTED}</p>
     * <p>When <code>EXTRA_STATE</code> is set
     * to </code>STATE_AUDIO_CONNECTED</code>,
     * it also includes {@link #EXTRA_AUDIO_WBS}
     * indicating wide band speech support.</p>
     */
    public static final String ACTION_AUDIO_STATE_CHANGED =
        "android.bluetooth.headsetclient.profile.action.AUDIO_STATE_CHANGED";

    /**
     * Intent sending updates of the Audio Gateway state.
     * Each extra is being sent only when value it
     * represents has been changed recently on AG.
     * <p>It can contain one or more of the following extras:
     * {@link #EXTRA_NETWORK_STATUS},
     * {@link #EXTRA_NETWORK_SIGNAL_STRENGTH},
     * {@link #EXTRA_NETWORK_ROAMING},
     * {@link #EXTRA_BATTERY_LEVEL},
     * {@link #EXTRA_OPERATOR_NAME},
     * {@link #EXTRA_VOICE_RECOGNITION},
     * {@link #EXTRA_IN_BAND_RING}</p>
     */
    public static final String ACTION_AG_EVENT =
            "android.bluetooth.headsetclient.profile.action.AG_EVENT";

    /**
     * Intent sent whenever state of a call changes.
     *
     * <p>It includes:
     * {@link #EXTRA_CALL},
     * with value of {@link BluetoothHeadsetClientCall} instance,
     * representing actual call state.</p>
     */
    public static final String ACTION_CALL_CHANGED =
            "android.bluetooth.headsetclient.profile.action.AG_CALL_CHANGED";

    /**
     * Intent that notifies about the result of the last issued action.
     * Please note that not every action results in explicit action result code being sent.
     * Instead other notifications about new Audio Gateway state might be sent,
     * like <code>ACTION_AG_EVENT</code> with <code>EXTRA_VOICE_RECOGNITION</code> value
     * when for example user started voice recognition from HF unit.
     */
    public static final String ACTION_RESULT =
            "android.bluetooth.headsetclient.profile.action.RESULT";

    /**
     * Intent that notifies about the number attached to the last voice tag
     * recorded on AG.
     *
     * <p>It contains:
     * {@link #EXTRA_NUMBER},
     * with a <code>String</code> value representing phone number.</p>
     */
    public static final String ACTION_LAST_VTAG =
            "android.bluetooth.headsetclient.profile.action.LAST_VTAG";

    public static final int STATE_AUDIO_DISCONNECTED = 0;
    public static final int STATE_AUDIO_CONNECTING = 1;
    public static final int STATE_AUDIO_CONNECTED = 2;

    /**
     * Extra with information if connected audio is WBS.
     * <p>Possible values: <code>true</code>,
     *                     <code>false</code>.</p>
     */
    public static final String EXTRA_AUDIO_WBS =
            "android.bluetooth.headsetclient.extra.AUDIO_WBS";

    /**
     * Extra for AG_EVENT indicates network status.
     * <p>Value: 0 - network unavailable,
     *           1 - network available </p>
     */
    public static final String EXTRA_NETWORK_STATUS =
            "android.bluetooth.headsetclient.extra.NETWORK_STATUS";
    /**
     * Extra for AG_EVENT intent indicates network signal strength.
     * <p>Value: <code>Integer</code> representing signal strength.</p>
     */
    public static final String EXTRA_NETWORK_SIGNAL_STRENGTH =
            "android.bluetooth.headsetclient.extra.NETWORK_SIGNAL_STRENGTH";
    /**
     * Extra for AG_EVENT intent indicates roaming state.
     * <p>Value: 0 - no roaming
     *           1 - active roaming</p>
     */
    public static final String EXTRA_NETWORK_ROAMING =
            "android.bluetooth.headsetclient.extra.NETWORK_ROAMING";
    /**
     * Extra for AG_EVENT intent indicates the battery level.
     * <p>Value: <code>Integer</code> representing signal strength.</p>
     */
    public static final String EXTRA_BATTERY_LEVEL =
            "android.bluetooth.headsetclient.extra.BATTERY_LEVEL";
    /**
     * Extra for AG_EVENT intent indicates operator name.
     * <p>Value: <code>String</code> representing operator name.</p>
     */
    public static final String EXTRA_OPERATOR_NAME =
            "android.bluetooth.headsetclient.extra.OPERATOR_NAME";
    /**
     * Extra for AG_EVENT intent indicates voice recognition state.
     * <p>Value:
     *          0 - voice recognition stopped,
     *          1 - voice recognition started.</p>
     */
    public static final String EXTRA_VOICE_RECOGNITION =
            "android.bluetooth.headsetclient.extra.VOICE_RECOGNITION";
    /**
     * Extra for AG_EVENT intent indicates in band ring state.
     * <p>Value:
     *          0 - in band ring tone not supported, or
     *          1 - in band ring tone supported.</p>
     */
    public static final String EXTRA_IN_BAND_RING =
            "android.bluetooth.headsetclient.extra.IN_BAND_RING";

    /**
     * Extra for AG_EVENT intent indicates subscriber info.
     * <p>Value: <code>String</code> containing subscriber information.</p>
     */
    public static final String EXTRA_SUBSCRIBER_INFO =
            "android.bluetooth.headsetclient.extra.SUBSCRIBER_INFO";

    /**
     *  Extra for AG_CALL_CHANGED intent indicates the
     *  {@link BluetoothHeadsetClientCall} object that has changed.
     */
    public static final String EXTRA_CALL =
            "android.bluetooth.headsetclient.extra.CALL";

    /**
     * Extra for ACTION_LAST_VTAG intent.
     * <p>Value: <code>String</code> representing phone number
     * corresponding to last voice tag recorded on AG</p>
     */
    public static final String EXTRA_NUMBER =
            "android.bluetooth.headsetclient.extra.NUMBER";

    /**
     * Extra for ACTION_RESULT intent that shows the result code of
     * last issued action.
     * <p>Possible results:
     * {@link #ACTION_RESULT_OK},
     * {@link #ACTION_RESULT_ERROR},
     * {@link #ACTION_RESULT_ERROR_NO_CARRIER},
     * {@link #ACTION_RESULT_ERROR_BUSY},
     * {@link #ACTION_RESULT_ERROR_NO_ANSWER},
     * {@link #ACTION_RESULT_ERROR_DELAYED},
     * {@link #ACTION_RESULT_ERROR_BLACKLISTED},
     * {@link #ACTION_RESULT_ERROR_CME}</p>
     */
    public static final String EXTRA_RESULT_CODE =
            "android.bluetooth.headsetclient.extra.RESULT_CODE";

    /**
     * Extra for ACTION_RESULT intent that shows the extended result code of
     * last issued action.
     * <p>Value: <code>Integer</code> - error code.</p>
     */
    public static final String EXTRA_CME_CODE =
            "android.bluetooth.headsetclient.extra.CME_CODE";

    /* Extras for AG_FEATURES, extras type is boolean */
    // TODO verify if all of those are actually useful
    /**
     * AG feature: three way calling.
     */
    public final static String EXTRA_AG_FEATURE_3WAY_CALLING =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_3WAY_CALLING";
    /**
     * AG feature: voice recognition.
     */
    public final static String EXTRA_AG_FEATURE_VOICE_RECOGNITION =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_VOICE_RECOGNITION";
    /**
     * AG feature: fetching phone number for voice tagging procedure.
     */
    public final static String EXTRA_AG_FEATURE_ATTACH_NUMBER_TO_VT =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_ATTACH_NUMBER_TO_VT";
    /**
     * AG feature: ability to reject incoming call.
     */
    public final static String EXTRA_AG_FEATURE_REJECT_CALL =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_REJECT_CALL";
    /**
     * AG feature: enhanced call handling (terminate specific call, private consultation).
     */
    public final static String EXTRA_AG_FEATURE_ECC =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_ECC";
    /**
     * AG feature: response and hold.
     */
    public final static String EXTRA_AG_FEATURE_RESPONSE_AND_HOLD =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_RESPONSE_AND_HOLD";
    /**
     * AG call handling feature: accept held or waiting call in three way calling scenarios.
     */
    public final static String EXTRA_AG_FEATURE_ACCEPT_HELD_OR_WAITING_CALL =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_ACCEPT_HELD_OR_WAITING_CALL";
    /**
     * AG call handling feature: release held or waiting call in three way calling scenarios.
     */
    public final static String EXTRA_AG_FEATURE_RELEASE_HELD_OR_WAITING_CALL =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_RELEASE_HELD_OR_WAITING_CALL";
    /**
     * AG call handling feature: release active call and accept held or waiting call in three way
     * calling scenarios.
     */
    public final static String EXTRA_AG_FEATURE_RELEASE_AND_ACCEPT =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_RELEASE_AND_ACCEPT";
    /**
     * AG call handling feature: merge two calls, held and active - multi party conference mode.
     */
    public final static String EXTRA_AG_FEATURE_MERGE =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_MERGE";
    /**
     * AG call handling feature: merge calls and disconnect from multi party
     * conversation leaving peers connected to each other.
     * Note that this feature needs to be supported by mobile network operator
     * as it requires connection and billing transfer.
     */
    public final static String EXTRA_AG_FEATURE_MERGE_AND_DETACH =
            "android.bluetooth.headsetclient.extra.EXTRA_AG_FEATURE_MERGE_AND_DETACH";

    /* Action result codes */
    public final static int ACTION_RESULT_OK = 0;
    public final static int ACTION_RESULT_ERROR = 1;
    public final static int ACTION_RESULT_ERROR_NO_CARRIER = 2;
    public final static int ACTION_RESULT_ERROR_BUSY = 3;
    public final static int ACTION_RESULT_ERROR_NO_ANSWER = 4;
    public final static int ACTION_RESULT_ERROR_DELAYED = 5;
    public final static int ACTION_RESULT_ERROR_BLACKLISTED = 6;
    public final static int ACTION_RESULT_ERROR_CME = 7;

    /* Detailed CME error codes */
    public final static int CME_PHONE_FAILURE                           = 0;
    public final static int CME_NO_CONNECTION_TO_PHONE                  = 1;
    public final static int CME_OPERATION_NOT_ALLOWED                   = 3;
    public final static int CME_OPERATION_NOT_SUPPORTED                 = 4;
    public final static int CME_PHSIM_PIN_REQUIRED                      = 5;
    public final static int CME_PHFSIM_PIN_REQUIRED                     = 6;
    public final static int CME_PHFSIM_PUK_REQUIRED                     = 7;
    public final static int CME_SIM_NOT_INSERTED                        = 10;
    public final static int CME_SIM_PIN_REQUIRED                        = 11;
    public final static int CME_SIM_PUK_REQUIRED                        = 12;
    public final static int CME_SIM_FAILURE                             = 13;
    public final static int CME_SIM_BUSY                                = 14;
    public final static int CME_SIM_WRONG                               = 15;
    public final static int CME_INCORRECT_PASSWORD                      = 16;
    public final static int CME_SIM_PIN2_REQUIRED                       = 17;
    public final static int CME_SIM_PUK2_REQUIRED                       = 18;
    public final static int CME_MEMORY_FULL                             = 20;
    public final static int CME_INVALID_INDEX                           = 21;
    public final static int CME_NOT_FOUND                               = 22;
    public final static int CME_MEMORY_FAILURE                          = 23;
    public final static int CME_TEXT_STRING_TOO_LONG                    = 24;
    public final static int CME_INVALID_CHARACTER_IN_TEXT_STRING        = 25;
    public final static int CME_DIAL_STRING_TOO_LONG                    = 26;
    public final static int CME_INVALID_CHARACTER_IN_DIAL_STRING        = 27;
    public final static int CME_NO_NETWORK_SERVICE                      = 30;
    public final static int CME_NETWORK_TIMEOUT                         = 31;
    public final static int CME_EMERGENCY_SERVICE_ONLY                  = 32;
    public final static int CME_NO_SIMULTANOUS_VOIP_CS_CALLS            = 33;
    public final static int CME_NOT_SUPPORTED_FOR_VOIP                  = 34;
    public final static int CME_SIP_RESPONSE_CODE                       = 35;
    public final static int CME_NETWORK_PERSONALIZATION_PIN_REQUIRED    = 40;
    public final static int CME_NETWORK_PERSONALIZATION_PUK_REQUIRED    = 41;
    public final static int CME_NETWORK_SUBSET_PERSONALIZATION_PIN_REQUIRED   = 42;
    public final static int CME_NETWORK_SUBSET_PERSONALIZATION_PUK_REQUIRED   = 43;
    public final static int CME_SERVICE_PROVIDER_PERSONALIZATION_PIN_REQUIRED = 44;
    public final static int CME_SERVICE_PROVIDER_PERSONALIZATION_PUK_REQUIRED = 45;
    public final static int CME_CORPORATE_PERSONALIZATION_PIN_REQUIRED  = 46;
    public final static int CME_CORPORATE_PERSONALIZATION_PUK_REQUIRED  = 47;
    public final static int CME_HIDDEN_KEY_REQUIRED                     = 48;
    public final static int CME_EAP_NOT_SUPPORTED                       = 49;
    public final static int CME_INCORRECT_PARAMETERS                    = 50;

    /* Action policy for other calls when accepting call */
    public static final int CALL_ACCEPT_NONE = 0;
    public static final int CALL_ACCEPT_HOLD = 1;
    public static final int CALL_ACCEPT_TERMINATE = 2;

    private Context mContext;
    private ServiceListener mServiceListener;
    private IBluetoothHeadsetClient mService;
    private BluetoothAdapter mAdapter;

    final private IBluetoothStateChangeCallback mBluetoothStateChangeCallback =
            new IBluetoothStateChangeCallback.Stub() {
                @Override
                public void onBluetoothStateChange(boolean up) {
                    if (DBG) Log.d(TAG, "onBluetoothStateChange: up=" + up);
                    if (!up) {
                        if (VDBG) Log.d(TAG,"Unbinding service...");
                        synchronized (mConnection) {
                            try {
                                mService = null;
                                mContext.unbindService(mConnection);
                            } catch (Exception re) {
                                Log.e(TAG,"",re);
                            }
                        }
                    } else {
                        synchronized (mConnection) {
                            try {
                                if (mService == null) {
                                    if (VDBG) Log.d(TAG,"Binding service...");
                                    Intent intent = new Intent(IBluetoothHeadsetClient.class.getName());
                                    doBind();
                                }
                            } catch (Exception re) {
                                Log.e(TAG,"",re);
                            }
                        }
                    }
                }
        };

    /**
     * Create a BluetoothHeadsetClient proxy object.
     */
    /*package*/ BluetoothHeadsetClient(Context context, ServiceListener l) {
        mContext = context;
        mServiceListener = l;
        mAdapter = BluetoothAdapter.getDefaultAdapter();

        IBluetoothManager mgr = mAdapter.getBluetoothManager();
        if (mgr != null) {
            try {
                mgr.registerStateChangeCallback(mBluetoothStateChangeCallback);
            } catch (RemoteException e) {
                Log.e(TAG,"",e);
            }
        }

        doBind();
    }

    boolean doBind() {
        Intent intent = new Intent(IBluetoothHeadsetClient.class.getName());
        ComponentName comp = intent.resolveSystemService(mContext.getPackageManager(), 0);
        intent.setComponent(comp);
        if (comp == null || !mContext.bindServiceAsUser(intent, mConnection, 0,
                 android.os.Process.myUserHandle())) {
            Log.e(TAG, "Could not bind to Bluetooth Headset Client Service with " + intent);
            return false;
        }
        return true;
    }

    /**
     * Close the connection to the backing service.
     * Other public functions of BluetoothHeadsetClient will return default error
     * results once close() has been called. Multiple invocations of close()
     * are ok.
     */
    /*package*/ void close() {
        if (VDBG) log("close()");

        IBluetoothManager mgr = mAdapter.getBluetoothManager();
        if (mgr != null) {
            try {
                mgr.unregisterStateChangeCallback(mBluetoothStateChangeCallback);
            } catch (Exception e) {
                Log.e(TAG,"",e);
            }
        }

        synchronized (mConnection) {
            if (mService != null) {
                try {
                    mService = null;
                    mContext.unbindService(mConnection);
                } catch (Exception re) {
                    Log.e(TAG,"",re);
                }
            }
        }
        mServiceListener = null;
    }

    /**
     * Connects to remote device.
     *
     * Currently, the system supports only 1 connection. So, in case of the
     * second connection, this implementation will disconnect already connected
     * device automatically and will process the new one.
     *
     * @param device    a remote device we want connect to
     * @return <code>true</code> if command has been issued successfully;
     *          <code>false</code> otherwise;
     *          upon completion HFP sends {@link #ACTION_CONNECTION_STATE_CHANGED}
     *          intent.
     */
    public boolean connect(BluetoothDevice device) {
        if (DBG) log("connect(" + device + ")");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.connect(device);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Disconnects remote device
     *
     * @param device    a remote device we want disconnect
     * @return          <code>true</code> if command has been issued successfully;
     *                  <code>false</code> otherwise;
     *                  upon completion HFP sends {@link #ACTION_CONNECTION_STATE_CHANGED}
     *                  intent.
     */
    public boolean disconnect(BluetoothDevice device) {
        if (DBG) log("disconnect(" + device + ")");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.disconnect(device);
            } catch (RemoteException e) {
              Log.e(TAG, Log.getStackTraceString(new Throwable()));
              return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Return the list of connected remote devices
     *
     * @return list of connected devices; empty list if nothing is connected.
     */
    @Override
    public List<BluetoothDevice> getConnectedDevices() {
        if (VDBG) log("getConnectedDevices()");
        if (mService != null && isEnabled()) {
            try {
                return mService.getConnectedDevices();
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
    }

    /**
     * Returns list of remote devices in a particular state
     *
     * @param states    collection of states
     * @return          list of devices that state matches the states listed in
     *                  <code>states</code>; empty list if nothing matches the
     *                  <code>states</code>
     */
    @Override
    public List<BluetoothDevice> getDevicesMatchingConnectionStates(int[] states) {
        if (VDBG) log("getDevicesMatchingStates()");
        if (mService != null && isEnabled()) {
            try {
                return mService.getDevicesMatchingConnectionStates(states);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
    }

    /**
     * Returns state of the <code>device</code>
     *
     * @param device    a remote device
     * @return          the state of connection of the device
     */
    @Override
    public int getConnectionState(BluetoothDevice device) {
        if (VDBG) log("getConnectionState(" + device + ")");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.getConnectionState(device);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return BluetoothProfile.STATE_DISCONNECTED;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return BluetoothProfile.STATE_DISCONNECTED;
    }

    /**
     * Set priority of the profile
     *
     * The device should already be paired.
     */
    public boolean setPriority(BluetoothDevice device, int priority) {
        if (DBG) log("setPriority(" + device + ", " + priority + ")");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            if (priority != BluetoothProfile.PRIORITY_OFF &&
                    priority != BluetoothProfile.PRIORITY_ON) {
              return false;
            }
            try {
                return mService.setPriority(device, priority);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Get the priority of the profile.
     */
    public int getPriority(BluetoothDevice device) {
        if (VDBG) log("getPriority(" + device + ")");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.getPriority(device);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return PRIORITY_OFF;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return PRIORITY_OFF;
    }

    /**
     * Starts voice recognition.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_AG_EVENT}
     *                   intent.
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_VOICE_RECOGNITION}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean startVoiceRecognition(BluetoothDevice device) {
        if (DBG) log("startVoiceRecognition()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.startVoiceRecognition(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Stops voice recognition.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_AG_EVENT}
     *                   intent.
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_VOICE_RECOGNITION}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean stopVoiceRecognition(BluetoothDevice device) {
        if (DBG) log("stopVoiceRecognition()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.stopVoiceRecognition(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Returns list of all calls in any state.
     *
     * @param device    remote device
     * @return          list of calls; empty list if none call exists
     */
    public List<BluetoothHeadsetClientCall> getCurrentCalls(BluetoothDevice device) {
        if (DBG) log("getCurrentCalls()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.getCurrentCalls(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return null;
    }

    /**
     * Returns list of current values of AG indicators.
     *
     * @param device    remote device
     * @return          bundle of AG  indicators; null if device is not in
     *                  CONNECTED state
     */
    public Bundle getCurrentAgEvents(BluetoothDevice device) {
        if (DBG) log("getCurrentCalls()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.getCurrentAgEvents(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return null;
    }

    /**
     * Accepts a call
     *
     * @param device    remote device
     * @param flag      action policy while accepting a call. Possible values
     *                   {@link #CALL_ACCEPT_NONE}, {@link #CALL_ACCEPT_HOLD},
     *                   {@link #CALL_ACCEPT_TERMINATE}
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                   intent.
     */
    public boolean acceptCall(BluetoothDevice device, int flag) {
        if (DBG) log("acceptCall()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.acceptCall(device, flag);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Holds a call.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                   intent.
     */
    public boolean holdCall(BluetoothDevice device) {
        if (DBG) log("holdCall()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.holdCall(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Rejects a call.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                   intent.
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_REJECT_CALL}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean rejectCall(BluetoothDevice device) {
        if (DBG) log("rejectCall()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.rejectCall(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Terminates a specified call.
     *
     * Works only when Extended Call Control is supported by Audio Gateway.
     *
     * @param device    remote device
     * @param call      Handle of call obtained in {@link dial()} or obtained via
     *                  {@link ACTION_CALL_CHANGED}. {@code call} may be null in which
     *                  case we will hangup all active calls.
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                   intent.
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_ECC}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean terminateCall(BluetoothDevice device, BluetoothHeadsetClientCall call) {
        if (DBG) log("terminateCall()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.terminateCall(device, call);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Enters private mode with a specified call.
     *
     * Works only when Extended Call Control is supported by Audio Gateway.
     *
     * @param device    remote device
     * @param index     index of the call to connect in private mode
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                   intent.
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_ECC}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean enterPrivateMode(BluetoothDevice device, int index) {
        if (DBG) log("enterPrivateMode()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.enterPrivateMode(device, index);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Performs explicit call transfer.
     *
     * That means connect other calls and disconnect.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                   intent.
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_MERGE_AND_DETACH}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean explicitCallTransfer(BluetoothDevice device) {
        if (DBG) log("explicitCallTransfer()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.explicitCallTransfer(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Places a call with specified number.
     *
     * @param device    remote device
     * @param number    valid phone number
     * @return          <code>{@link BluetoothHeadsetClientCall} call</code> if command has been
     *                  issued successfully;
     *                  <code>{@link null}</code> otherwise;
     *                  upon completion HFP sends {@link #ACTION_CALL_CHANGED}
     *                  intent in case of success; {@link #ACTION_RESULT} is sent
     *                  otherwise;
     */
    public BluetoothHeadsetClientCall dial(BluetoothDevice device, String number) {
        if (DBG) log("dial()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.dial(device, number);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return null;
    }

    /**
     * Sends DTMF code.
     *
     * Possible code values : 0,1,2,3,4,5,6,7,8,9,A,B,C,D,*,#
     *
     * @param device    remote device
     * @param code  ASCII code
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_RESULT} intent;
     */
    public boolean sendDTMF(BluetoothDevice device, byte code) {
        if (DBG) log("sendDTMF()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.sendDTMF(device, code);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Get a number corresponding to last voice tag recorded on AG.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_LAST_VTAG}
     *                   or {@link #ACTION_RESULT} intent;
     *
     * <p>Feature required for successful execution is being reported by:
     * {@link #EXTRA_AG_FEATURE_ATTACH_NUMBER_TO_VT}.
     * This method invocation will fail silently when feature is not supported.</p>
     */
    public boolean getLastVoiceTagNumber(BluetoothDevice device) {
        if (DBG) log("getLastVoiceTagNumber()");
        if (mService != null && isEnabled() &&
                isValidDevice(device)) {
            try {
                return mService.getLastVoiceTagNumber(device);
            } catch (RemoteException e) {
                Log.e(TAG,  Log.getStackTraceString(new Throwable()));
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Returns current audio state of Audio Gateway.
     *
     * Note: This is an internal function and shouldn't be exposed
     */
    public int getAudioState(BluetoothDevice device) {
        if (VDBG) log("getAudioState");
        if (mService != null && isEnabled()) {
            try {
                return mService.getAudioState(device);
            } catch (RemoteException e) {Log.e(TAG, e.toString());}
        } else {
            Log.w(TAG, "Proxy not attached to service");
            if (DBG) Log.d(TAG, Log.getStackTraceString(new Throwable()));
        }
        return BluetoothHeadsetClient.STATE_AUDIO_DISCONNECTED;
    }

    /**
     * Sets whether audio routing is allowed.
     *
     * @param device    remote device
     * @param allowed   if routing is allowed to the device
     * Note: This is an internal function and shouldn't be exposed
     */
    public void setAudioRouteAllowed(BluetoothDevice device, boolean allowed) {
        if (VDBG) log("setAudioRouteAllowed");
        if (mService != null && isEnabled()) {
            try {
                mService.setAudioRouteAllowed(device, allowed);
            } catch (RemoteException e) {Log.e(TAG, e.toString());}
        } else {
            Log.w(TAG, "Proxy not attached to service");
            if (DBG) Log.d(TAG, Log.getStackTraceString(new Throwable()));
        }
    }

    /**
     * Returns whether audio routing is allowed.
     * @param device    remote device
     * @return whether the command succeeded
     * Note: This is an internal function and shouldn't be exposed
     */
    public boolean getAudioRouteAllowed(BluetoothDevice device) {
        if (VDBG) log("getAudioRouteAllowed");
        if (mService != null && isEnabled()) {
            try {
                return mService.getAudioRouteAllowed(device);
            } catch (RemoteException e) {Log.e(TAG, e.toString());}
        } else {
            Log.w(TAG, "Proxy not attached to service");
            if (DBG) Log.d(TAG, Log.getStackTraceString(new Throwable()));
        }
        return false;
    }

    /**
     * Initiates a connection of audio channel.
     *
     * It setup SCO channel with remote connected Handsfree AG device.
     *
     * @param device    remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_AUDIO_STATE_CHANGED}
     *                   intent;
     */
    public boolean connectAudio(BluetoothDevice device) {
        if (mService != null && isEnabled()) {
            try {
                return mService.connectAudio(device);
            } catch (RemoteException e) {
                Log.e(TAG, e.toString());
            }
        } else {
            Log.w(TAG, "Proxy not attached to service");
            if (DBG) Log.d(TAG, Log.getStackTraceString(new Throwable()));
        }
        return false;
    }

    /**
     * Disconnects audio channel.
     *
     * It tears down the SCO channel from remote AG device.
     *
     * @param   device  remote device
     * @return          <code>true</code> if command has been issued successfully;
     *                   <code>false</code> otherwise;
     *                   upon completion HFP sends {@link #ACTION_AUDIO_STATE_CHANGED}
     *                   intent;
     */
    public boolean disconnectAudio(BluetoothDevice device) {
        if (mService != null && isEnabled()) {
            try {
                return mService.disconnectAudio(device);
            } catch (RemoteException e) {
                Log.e(TAG, e.toString());
            }
        } else {
            Log.w(TAG, "Proxy not attached to service");
            if (DBG) Log.d(TAG, Log.getStackTraceString(new Throwable()));
        }
        return false;
    }

    /**
     * Get Audio Gateway features
     *
     * @param device    remote device
     * @return          bundle of AG features; null if no service or
     *                  AG not connected
     */
    public Bundle getCurrentAgFeatures(BluetoothDevice device) {
        if (mService != null && isEnabled()) {
            try {
                return mService.getCurrentAgFeatures(device);
            } catch (RemoteException e) {
                Log.e(TAG, e.toString());
            }
        } else {
            Log.w(TAG, "Proxy not attached to service");
            if (DBG) Log.d(TAG, Log.getStackTraceString(new Throwable()));
        }
        return null;
    }


    private ServiceConnection mConnection = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName className, IBinder service) {
            if (DBG) Log.d(TAG, "Proxy object connected");
            mService = IBluetoothHeadsetClient.Stub.asInterface(service);

            if (mServiceListener != null) {
                mServiceListener.onServiceConnected(BluetoothProfile.HEADSET_CLIENT,
                        BluetoothHeadsetClient.this);
            }
        }
        @Override
        public void onServiceDisconnected(ComponentName className) {
            if (DBG) Log.d(TAG, "Proxy object disconnected");
            mService = null;
            if (mServiceListener != null) {
                mServiceListener.onServiceDisconnected(BluetoothProfile.HEADSET_CLIENT);
            }
        }
    };

    private boolean isEnabled() {
       if (mAdapter.getState() == BluetoothAdapter.STATE_ON) return true;
       return false;
    }

    private boolean isValidDevice(BluetoothDevice device) {
       if (device == null) return false;

       if (BluetoothAdapter.checkBluetoothAddress(device.getAddress())) return true;
       return false;
    }

    private static void log(String msg) {
        Log.d(TAG, msg);
    }
}