android/bluetooth/BluetoothA2dpSink.java

/*
 * 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.Manifest;
import android.annotation.NonNull;
import android.annotation.RequiresPermission;
import android.annotation.SdkConstant;
import android.annotation.SuppressLint;
import android.annotation.SystemApi;
import android.annotation.SdkConstant.SdkConstantType;
import android.bluetooth.annotations.RequiresBluetoothConnectPermission;
import android.bluetooth.annotations.RequiresLegacyBluetoothAdminPermission;
import android.bluetooth.annotations.RequiresLegacyBluetoothPermission;
import android.compat.annotation.UnsupportedAppUsage;
import android.content.Attributable;
import android.content.AttributionSource;
import android.content.Context;
import android.os.Binder;
import android.os.Build;
import android.os.IBinder;
import android.os.RemoteException;
import android.util.Log;

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

/**
 * This class provides the public APIs to control the Bluetooth A2DP Sink
 * profile.
 *
 * <p>BluetoothA2dpSink is a proxy object for controlling the Bluetooth A2DP Sink
 * Service via IPC. Use {@link BluetoothAdapter#getProfileProxy} to get
 * the BluetoothA2dpSink proxy object.
 *
 * @hide
 */
@SystemApi
public final class BluetoothA2dpSink implements BluetoothProfile {
    private static final String TAG = "BluetoothA2dpSink";
    private static final boolean DBG = true;
    private static final boolean VDBG = false;

    /**
     * Intent used to broadcast the change in connection state of the A2DP Sink
     * profile.
     *
     * <p>This intent will have 3 extras:
     * <ul>
     * <li> {@link #EXTRA_STATE} - The current state of the profile. </li>
     * <li> {@link #EXTRA_PREVIOUS_STATE}- The previous state of the profile.</li>
     * <li> {@link BluetoothDevice#EXTRA_DEVICE} - The remote device. </li>
     * </ul>
     *
     * <p>{@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} can be any of
     * {@link #STATE_DISCONNECTED}, {@link #STATE_CONNECTING},
     * {@link #STATE_CONNECTED}, {@link #STATE_DISCONNECTING}.
     *
     * @hide
     */
    @SystemApi
    @SuppressLint("ActionValue")
    @RequiresBluetoothConnectPermission
    @RequiresPermission(Manifest.permission.BLUETOOTH_CONNECT)
    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
    public static final String ACTION_CONNECTION_STATE_CHANGED =
            "android.bluetooth.a2dp-sink.profile.action.CONNECTION_STATE_CHANGED";

    private final BluetoothAdapter mAdapter;
    private final AttributionSource mAttributionSource;
    private final BluetoothProfileConnector<IBluetoothA2dpSink> mProfileConnector =
            new BluetoothProfileConnector(this, BluetoothProfile.A2DP_SINK,
                    "BluetoothA2dpSink", IBluetoothA2dpSink.class.getName()) {
                @Override
                public IBluetoothA2dpSink getServiceInterface(IBinder service) {
                    return IBluetoothA2dpSink.Stub.asInterface(Binder.allowBlocking(service));
                }
    };

    /**
     * Create a BluetoothA2dp proxy object for interacting with the local
     * Bluetooth A2DP service.
     */
    /* package */ BluetoothA2dpSink(Context context, ServiceListener listener,
            BluetoothAdapter adapter) {
        mAdapter = adapter;
        mAttributionSource = adapter.getAttributionSource();
        mProfileConnector.connect(context, listener);
    }

    /*package*/ void close() {
        mProfileConnector.disconnect();
    }

    private IBluetoothA2dpSink getService() {
        return mProfileConnector.getService();
    }

    @Override
    public void finalize() {
        close();
    }

    /**
     * Initiate connection to a profile of the remote bluetooth device.
     *
     * <p> Currently, the system supports only 1 connection to the
     * A2DP profile. The API will automatically disconnect connected
     * devices before connecting.
     *
     * <p> This API returns false in scenarios like the profile on the
     * device is already connected or Bluetooth is not turned on.
     * When this API returns true, it is guaranteed that
     * connection state intent for the profile will be broadcasted with
     * the state. Users can get the connection state of the profile
     * from this intent.
     *
     * @param device Remote Bluetooth Device
     * @return false on immediate error, true otherwise
     * @hide
     */
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public boolean connect(BluetoothDevice device) {
        if (DBG) log("connect(" + device + ")");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.connect(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Initiate disconnection from a profile
     *
     * <p> This API will return false in scenarios like the profile on the
     * Bluetooth device is not in connected state etc. When this API returns,
     * true, it is guaranteed that the connection state change
     * intent will be broadcasted with the state. Users can get the
     * disconnection state of the profile from this intent.
     *
     * <p> If the disconnection is initiated by a remote device, the state
     * will transition from {@link #STATE_CONNECTED} to
     * {@link #STATE_DISCONNECTED}. If the disconnect is initiated by the
     * host (local) device the state will transition from
     * {@link #STATE_CONNECTED} to state {@link #STATE_DISCONNECTING} to
     * state {@link #STATE_DISCONNECTED}. The transition to
     * {@link #STATE_DISCONNECTING} can be used to distinguish between the
     * two scenarios.
     *
     * @param device Remote Bluetooth Device
     * @return false on immediate error, true otherwise
     * @hide
     */
    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
    @RequiresLegacyBluetoothAdminPermission
    @RequiresBluetoothConnectPermission
    @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
    public boolean disconnect(BluetoothDevice device) {
        if (DBG) log("disconnect(" + device + ")");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.disconnect(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * {@inheritDoc}
     *
     * @hide
     */
    @Override
    @RequiresBluetoothConnectPermission
    @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
    public List<BluetoothDevice> getConnectedDevices() {
        if (VDBG) log("getConnectedDevices()");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled()) {
            try {
                return Attributable.setAttributionSource(
                        service.getConnectedDevices(mAttributionSource), mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
    }

    /**
     * {@inheritDoc}
     *
     * @hide
     */
    @Override
    @RequiresBluetoothConnectPermission
    @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
    public List<BluetoothDevice> getDevicesMatchingConnectionStates(int[] states) {
        if (VDBG) log("getDevicesMatchingStates()");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled()) {
            try {
                return Attributable.setAttributionSource(
                        service.getDevicesMatchingConnectionStates(states, mAttributionSource),
                        mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
    }

    /**
     * {@inheritDoc}
     *
     * @hide
     */
    @Override
    @RequiresBluetoothConnectPermission
    @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
    public int getConnectionState(BluetoothDevice device) {
        if (VDBG) log("getState(" + device + ")");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.getConnectionState(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return BluetoothProfile.STATE_DISCONNECTED;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return BluetoothProfile.STATE_DISCONNECTED;
    }

    /**
     * Get the current audio configuration for the A2DP source device,
     * or null if the device has no audio configuration
     *
     * @param device Remote bluetooth device.
     * @return audio configuration for the device, or null
     *
     * {@see BluetoothAudioConfig}
     *
     * @hide
     */
    @RequiresLegacyBluetoothPermission
    @RequiresBluetoothConnectPermission
    @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
    public BluetoothAudioConfig getAudioConfig(BluetoothDevice device) {
        if (VDBG) log("getAudioConfig(" + device + ")");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.getAudioConfig(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return null;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return null;
    }

    /**
     * Set priority of the profile
     *
     * <p> The device should already be paired.
     * Priority can be one of {@link #PRIORITY_ON} or {@link #PRIORITY_OFF}
     *
     * @param device Paired bluetooth device
     * @param priority
     * @return true if priority is set, false on error
     * @hide
     */
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public boolean setPriority(BluetoothDevice device, int priority) {
        if (DBG) log("setPriority(" + device + ", " + priority + ")");
        return setConnectionPolicy(device, BluetoothAdapter.priorityToConnectionPolicy(priority));
    }

    /**
     * Set connection policy of the profile
     *
     * <p> The device should already be paired.
     * Connection policy can be one of {@link #CONNECTION_POLICY_ALLOWED},
     * {@link #CONNECTION_POLICY_FORBIDDEN}, {@link #CONNECTION_POLICY_UNKNOWN}
     *
     * @param device Paired bluetooth device
     * @param connectionPolicy is the connection policy to set to for this profile
     * @return true if connectionPolicy is set, false on error
     * @hide
     */
    @SystemApi
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED
    })
    public boolean setConnectionPolicy(@NonNull BluetoothDevice device,
            @ConnectionPolicy int connectionPolicy) {
        if (DBG) log("setConnectionPolicy(" + device + ", " + connectionPolicy + ")");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            if (connectionPolicy != BluetoothProfile.CONNECTION_POLICY_FORBIDDEN
                    && connectionPolicy != BluetoothProfile.CONNECTION_POLICY_ALLOWED) {
                return false;
            }
            try {
                return service.setConnectionPolicy(device, connectionPolicy, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Get the priority of the profile.
     *
     * <p> The priority can be any of:
     * {@link #PRIORITY_OFF}, {@link #PRIORITY_ON}, {@link #PRIORITY_UNDEFINED}
     *
     * @param device Bluetooth device
     * @return priority of the device
     * @hide
     */
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public int getPriority(BluetoothDevice device) {
        if (VDBG) log("getPriority(" + device + ")");
        return BluetoothAdapter.connectionPolicyToPriority(getConnectionPolicy(device));
    }

    /**
     * Get the connection policy of the profile.
     *
     * <p> The connection policy can be any of:
     * {@link #CONNECTION_POLICY_ALLOWED}, {@link #CONNECTION_POLICY_FORBIDDEN},
     * {@link #CONNECTION_POLICY_UNKNOWN}
     *
     * @param device Bluetooth device
     * @return connection policy of the device
     * @hide
     */
    @SystemApi
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public @ConnectionPolicy int getConnectionPolicy(@NonNull BluetoothDevice device) {
        if (VDBG) log("getConnectionPolicy(" + device + ")");
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.getConnectionPolicy(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return BluetoothProfile.CONNECTION_POLICY_FORBIDDEN;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return BluetoothProfile.CONNECTION_POLICY_FORBIDDEN;
    }

    /**
     * Check if audio is playing on the bluetooth device (A2DP profile is streaming music).
     *
     * @param device BluetoothDevice device
     * @return true if audio is playing (A2dp is streaming music), false otherwise
     *
     * @hide
     */
    @SystemApi
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public boolean isAudioPlaying(@NonNull BluetoothDevice device) {
        final IBluetoothA2dpSink service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.isA2dpPlaying(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return false;
    }

    /**
     * Helper for converting a state to a string.
     *
     * For debug use only - strings are not internationalized.
     *
     * @hide
     */
    public static String stateToString(int state) {
        switch (state) {
            case STATE_DISCONNECTED:
                return "disconnected";
            case STATE_CONNECTING:
                return "connecting";
            case STATE_CONNECTED:
                return "connected";
            case STATE_DISCONNECTING:
                return "disconnecting";
            case BluetoothA2dp.STATE_PLAYING:
                return "playing";
            case BluetoothA2dp.STATE_NOT_PLAYING:
                return "not playing";
            default:
                return "<unknown state " + state + ">";
        }
    }

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

    private static boolean isValidDevice(BluetoothDevice device) {
        return device != null && BluetoothAdapter.checkBluetoothAddress(device.getAddress());
    }

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