path: root/framework/java/android/bluetooth/BluetoothVolumeControl.java

/*
 * Copyright 2021 HIMSA II K/S - www.himsa.com.
 * Represented by EHIMA - www.ehima.com
 *
 * 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.IntRange;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.RequiresPermission;
import android.annotation.SdkConstant;
import android.annotation.SdkConstant.SdkConstantType;
import android.annotation.SuppressLint;
import android.annotation.SystemApi;
import android.bluetooth.annotations.RequiresBluetoothConnectPermission;
import android.compat.annotation.UnsupportedAppUsage;
import android.content.Attributable;
import android.content.AttributionSource;
import android.content.Context;
import android.os.Binder;
import android.os.IBinder;
import android.os.RemoteException;
import android.util.CloseGuard;
import android.util.Log;

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

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

    private CloseGuard mCloseGuard;

    /**
     * Intent used to broadcast the change in connection state of the Volume Control
     * 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.volume-control.profile.action.CONNECTION_STATE_CHANGED";

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

    /**
     * Create a BluetoothVolumeControl proxy object for interacting with the local
     * Bluetooth Volume Control service.
     */
    /*package*/ BluetoothVolumeControl(Context context, ServiceListener listener,
            BluetoothAdapter adapter) {
        mAdapter = adapter;
        mAttributionSource = adapter.getAttributionSource();
        mProfileConnector.connect(context, listener);
        mCloseGuard = new CloseGuard();
        mCloseGuard.open("close");
    }

    @RequiresPermission(Manifest.permission.BLUETOOTH_PRIVILEGED)
    protected void finalize() {
        if (mCloseGuard != null) {
            mCloseGuard.warnIfOpen();
        }
        close();
    }

    /*package*/
    @RequiresPermission(Manifest.permission.BLUETOOTH_PRIVILEGED)
    public void close() {
        mProfileConnector.disconnect();
    }

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

    /**
     * Get the list of connected devices. Currently at most one.
     *
     * @return list of connected devices
     *
     * @hide
     */
    @SystemApi
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public @NonNull List<BluetoothDevice> getConnectedDevices() {
        if (DBG) log("getConnectedDevices()");
        final IBluetoothVolumeControl service = getService();
        if (service != null && isEnabled()) {
            try {
                return Attributable.setAttributionSource(
                        service.getConnectedDevices(mAttributionSource), mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
    }

    /**
     * Get the list of devices matching specified states. Currently at most one.
     *
     * @return list of matching devices
     *
     * @hide
     */
    @RequiresBluetoothConnectPermission
    @RequiresPermission(Manifest.permission.BLUETOOTH_CONNECT)
    public List<BluetoothDevice> getDevicesMatchingConnectionStates(int[] states) {
        if (DBG) log("getDevicesMatchingStates()");
        final IBluetoothVolumeControl service = getService();
        if (service != null && isEnabled()) {
            try {
                return Attributable.setAttributionSource(
                        service.getDevicesMatchingConnectionStates(states, mAttributionSource),
                        mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
    }

    /**
     * Get connection state of device
     *
     * @return device connection state
     *
     * @hide
     */
    @RequiresBluetoothConnectPermission
    @RequiresPermission(Manifest.permission.BLUETOOTH_CONNECT)
    public int getConnectionState(BluetoothDevice device) {
        if (DBG) log("getConnectionState(" + device + ")");
        final IBluetoothVolumeControl service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.getConnectionState(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, Log.getStackTraceString(new Throwable()));
                return BluetoothProfile.STATE_DISCONNECTED;
            }
        }
        if (service == null) Log.w(TAG, "Proxy not attached to service");
        return BluetoothProfile.STATE_DISCONNECTED;
    }

    /**
     * Tells remote device to set an absolute volume.
     *
     * @param volume Absolute volume to be set on remote device.
     *               Minimum value is 0 and maximum value is 255
     * @hide
     */
    @SystemApi
    @RequiresBluetoothConnectPermission
    @RequiresPermission(allOf = {
            android.Manifest.permission.BLUETOOTH_CONNECT,
            android.Manifest.permission.BLUETOOTH_PRIVILEGED,
    })
    public void setVolume(@Nullable BluetoothDevice device,
            @IntRange(from = 0, to = 255) int volume) {
        if (DBG)
            log("setVolume(" + volume + ")");
        final IBluetoothVolumeControl service = getService();
        try {
            if (service != null && isEnabled()) {
                service.setVolume(device, volume, mAttributionSource);
                return;
            }
            if (service == null)
                Log.w(TAG, "Proxy not attached to service");
        } catch (RemoteException e) {
            Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
        }
    }

    /**
     * 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 IBluetoothVolumeControl 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, 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 IBluetoothVolumeControl service = getService();
        if (service != null && isEnabled() && isValidDevice(device)) {
            try {
                return service.getConnectionPolicy(device, mAttributionSource);
            } catch (RemoteException e) {
                Log.e(TAG, 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;
    }

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

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

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