/*
 * Copyright (C) 2009 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.Context;
import android.os.IBinder;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.RemoteException;
import android.os.ServiceManager;
import android.util.Log;

import java.io.IOException;
import java.io.UnsupportedEncodingException;

/**
 * Represents a remote Bluetooth device.
 *
 * TODO: unhide
 * @hide
 */
public final class BluetoothDevice implements Parcelable {
    private static final String TAG = "BluetoothDevice";

    /** We do not have a link key for the remote device, and are therefore not
     * bonded */
    public static final int BOND_NOT_BONDED = 0;
    /** We have a link key for the remote device, and are probably bonded. */
    public static final int BOND_BONDED = 1;
    /** We are currently attempting bonding */
    public static final int BOND_BONDING = 2;

    //TODO: Unify these result codes in BluetoothResult or BluetoothError
    /** A bond attempt failed because pins did not match, or remote device did
     * not respond to pin request in time */
    public static final int UNBOND_REASON_AUTH_FAILED = 1;
    /** A bond attempt failed because the other side explicilty rejected
     * bonding */
    public static final int UNBOND_REASON_AUTH_REJECTED = 2;
    /** A bond attempt failed because we canceled the bonding process */
    public static final int UNBOND_REASON_AUTH_CANCELED = 3;
    /** A bond attempt failed because we could not contact the remote device */
    public static final int UNBOND_REASON_REMOTE_DEVICE_DOWN = 4;
    /** A bond attempt failed because a discovery is in progress */
    public static final int UNBOND_REASON_DISCOVERY_IN_PROGRESS = 5;
    /** An existing bond was explicitly revoked */
    public static final int UNBOND_REASON_REMOVED = 6;

    /* The user will be prompted to enter a pin */
    public static final int PAIRING_VARIANT_PIN = 0;
    /* The user will be prompted to enter a passkey */
    public static final int PAIRING_VARIANT_PASSKEY = 1;
    /* The user will be prompted to confirm the passkey displayed on the screen */
    public static final int PAIRING_VARIANT_CONFIRMATION = 2;

    private static final int ADDRESS_LENGTH = 17;

    private static IBluetooth sService;  /* Guarenteed constant after first object constructed */

    private final String mAddress;

    /**
     * Create a new BluetoothDevice
     * Bluetooth MAC address must be upper case, such as "00:11:22:33:AA:BB",
     * and is validated in this constructor.
     * @param address valid Bluetooth MAC address
     * @throws RuntimeException Bluetooth is not available on this platform
     * @throws IllegalArgumentException address is invalid
     * @hide
     */
    /*package*/ BluetoothDevice(String address) {
        synchronized (BluetoothDevice.class) {
            if (sService == null) {
                IBinder b = ServiceManager.getService(Context.BLUETOOTH_SERVICE);
                if (b == null) {
                    throw new RuntimeException("Bluetooth service not available");
                }
                sService = IBluetooth.Stub.asInterface(b);
            }
        }

        if (!checkBluetoothAddress(address)) {
            throw new IllegalArgumentException(address + " is not a valid Bluetooth address");
        }

        mAddress = address;
    }

    @Override
    public boolean equals(Object o) {
        if (o instanceof BluetoothDevice) {
            return mAddress.equals(((BluetoothDevice)o).getAddress());
        }
        return false;
    }

    @Override
    public int hashCode() {
        return mAddress.hashCode();
    }

    @Override
    public String toString() {
        return mAddress;
    }

    public int describeContents() {
        return 0;
    }

    public static final Parcelable.Creator<BluetoothDevice> CREATOR =
            new Parcelable.Creator<BluetoothDevice>() {
        public BluetoothDevice createFromParcel(Parcel in) {
            return new BluetoothDevice(in.readString());
        }
        public BluetoothDevice[] newArray(int size) {
            return new BluetoothDevice[size];
        }
    };

    public void writeToParcel(Parcel out, int flags) {
        out.writeString(mAddress);
    }

    public String getAddress() {
        return mAddress;
    }

    /**
     * Get the friendly Bluetooth name of this remote device.
     *
     * This name is visible to remote Bluetooth devices. Currently it is only
     * possible to retrieve the Bluetooth name when Bluetooth is enabled.
     *
     * @return the Bluetooth name, or null if there was a problem.
     */
    public String getName() {
        try {
            return sService.getRemoteName(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return null;
    }

    /**
     * Create a bonding with a remote bluetooth device.
     *
     * This is an asynchronous call. The result of this bonding attempt can be
     * observed through BluetoothIntent.BOND_STATE_CHANGED_ACTION intents.
     *
     * @param address the remote device Bluetooth address.
     * @return false If there was an immediate problem creating the bonding,
     *         true otherwise.
     */
    public boolean createBond() {
        try {
            return sService.createBond(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    /**
     * Cancel an in-progress bonding request started with createBond.
     */
    public boolean cancelBondProcess() {
        try {
            return sService.cancelBondProcess(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    /**
     * Removes the remote device and the pairing information associated
     * with it.
     *
     * @return true if the device was disconnected, false otherwise and on
     *         error.
     */
    public boolean removeBond() {
        try {
            return sService.removeBond(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    /**
     * Get the bonding state of a remote device.
     *
     * Result is one of:
     * BluetoothError.*
     * BOND_*
     *
     * @param address Bluetooth hardware address of the remote device to check.
     * @return Result code
     */
    public int getBondState() {
        try {
            return sService.getBondState(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return BluetoothError.ERROR_IPC;
    }

    public int getBluetoothClass() {
        try {
            return sService.getRemoteClass(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return BluetoothError.ERROR_IPC;
    }

     public String[] getUuids() {
        try {
            return sService.getRemoteUuids(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return null;
    }

    public int getServiceChannel(String uuid) {
         try {
             return sService.getRemoteServiceChannel(mAddress, uuid);
         } catch (RemoteException e) {Log.e(TAG, "", e);}
         return BluetoothError.ERROR_IPC;
    }

    public boolean setPin(byte[] pin) {
        try {
            return sService.setPin(mAddress, pin);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    public boolean setPasskey(int passkey) {
        try {
            return sService.setPasskey(mAddress, passkey);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    public boolean setPairingConfirmation(boolean confirm) {
        try {
            return sService.setPairingConfirmation(mAddress, confirm);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    public boolean cancelPairingUserInput() {
        try {
            return sService.cancelPairingUserInput(mAddress);
        } catch (RemoteException e) {Log.e(TAG, "", e);}
        return false;
    }

    /**
     * Construct a secure RFCOMM socket ready to start an outgoing connection.
     * Call #connect on the returned #BluetoothSocket to begin the connection.
     * The remote device will be authenticated and communication on this socket
     * will be encrypted.
     * @param port    remote port
     * @return an RFCOMM BluetoothSocket
     * @throws IOException on error, for example Bluetooth not available, or
     *                     insufficient permissions.
     */
    public BluetoothSocket createRfcommSocket(int port) throws IOException {
        return new BluetoothSocket(BluetoothSocket.TYPE_RFCOMM, -1, true, true, this, port);
    }

    /**
     * Construct an insecure RFCOMM socket ready to start an outgoing
     * connection.
     * Call #connect on the returned #BluetoothSocket to begin the connection.
     * The remote device will not be authenticated and communication on this
     * socket will not be encrypted.
     * @param port    remote port
     * @return An RFCOMM BluetoothSocket
     * @throws IOException On error, for example Bluetooth not available, or
     *                     insufficient permissions.
     */
    public BluetoothSocket createInsecureRfcommSocket(int port) throws IOException {
        return new BluetoothSocket(BluetoothSocket.TYPE_RFCOMM, -1, false, false, this, port);
    }

    /**
     * Construct a SCO socket ready to start an outgoing connection.
     * Call #connect on the returned #BluetoothSocket to begin the connection.
     * @return a SCO BluetoothSocket
     * @throws IOException on error, for example Bluetooth not available, or
     *                     insufficient permissions.
     */
    public BluetoothSocket createScoSocket() throws IOException {
        return new BluetoothSocket(BluetoothSocket.TYPE_SCO, -1, true, true, this, -1);
    }

    /**
     * Check that a pin is valid and convert to byte array.
     *
     * Bluetooth pin's are 1 to 16 bytes of UTF8 characters.
     * @param pin pin as java String
     * @return the pin code as a UTF8 byte array, or null if it is an invalid
     *         Bluetooth pin.
     */
    public static byte[] convertPinToBytes(String pin) {
        if (pin == null) {
            return null;
        }
        byte[] pinBytes;
        try {
            pinBytes = pin.getBytes("UTF8");
        } catch (UnsupportedEncodingException uee) {
            Log.e(TAG, "UTF8 not supported?!?");  // this should not happen
            return null;
        }
        if (pinBytes.length <= 0 || pinBytes.length > 16) {
            return null;
        }
        return pinBytes;
    }

    /** Sanity check a bluetooth address, such as "00:43:A8:23:10:F0" */
    public static boolean checkBluetoothAddress(String address) {
        if (address == null || address.length() != ADDRESS_LENGTH) {
            return false;
        }
        for (int i = 0; i < ADDRESS_LENGTH; i++) {
            char c = address.charAt(i);
            switch (i % 3) {
            case 0:
            case 1:
                if (Character.digit(c, 16) != -1) {
                    break;  // hex character, OK
                }
                return false;
            case 2:
                if (c == ':') {
                    break;  // OK
                }
                return false;
            }
        }
        return true;
    }
}