package com.android.nfc.beam;

import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.util.Log;


/**
 * @hide
 */
public class BeamReceiveService extends Service implements BeamTransferManager.Callback {
    private static String TAG = "BeamReceiveService";
    private static boolean DBG = true;

    public static final String EXTRA_BEAM_TRANSFER_RECORD
            = "com.android.nfc.beam.EXTRA_BEAM_TRANSFER_RECORD";
    public static final String EXTRA_BEAM_COMPLETE_CALLBACK
            = "com.android.nfc.beam.TRANSFER_COMPLETE_CALLBACK";

    private BeamStatusReceiver mBeamStatusReceiver;
    private boolean mBluetoothEnabledByNfc;
    private int mStartId;
    private BeamTransferManager mTransferManager;
    private Messenger mCompleteCallback;

    private final BluetoothAdapter mBluetoothAdapter;
    private final BroadcastReceiver mBluetoothStateReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if (BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)) {
                int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE,
                        BluetoothAdapter.ERROR);
                if (state == BluetoothAdapter.STATE_OFF) {
                    mBluetoothEnabledByNfc = false;
                }
            }
        }
    };

    public BeamReceiveService() {
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        mStartId = startId;

        BeamTransferRecord transferRecord;
        if (intent == null ||
                (transferRecord = intent.getParcelableExtra(EXTRA_BEAM_TRANSFER_RECORD)) == null) {
            if (DBG) Log.e(TAG, "No transfer record provided. Stopping.");
            stopSelf(startId);
            return START_NOT_STICKY;
        }

        mCompleteCallback = intent.getParcelableExtra(EXTRA_BEAM_COMPLETE_CALLBACK);

        if (prepareToReceive(transferRecord)) {
            if (DBG) Log.i(TAG, "Ready for incoming Beam transfer");
            return START_STICKY;
        } else {
            invokeCompleteCallback(false);
            stopSelf(startId);
            return START_NOT_STICKY;
        }
    }

    // TODO: figure out a way to not duplicate this code
    @Override
    public void onCreate() {
        super.onCreate();

        // register BT state receiver
        IntentFilter filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
        registerReceiver(mBluetoothStateReceiver, filter);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mBeamStatusReceiver != null) {
            unregisterReceiver(mBeamStatusReceiver);
        }
        unregisterReceiver(mBluetoothStateReceiver);
    }

    boolean prepareToReceive(BeamTransferRecord transferRecord) {
        if (mTransferManager != null) {
            return false;
        }

        if (transferRecord.dataLinkType != BeamTransferRecord.DATA_LINK_TYPE_BLUETOOTH) {
            // only support BT
            return false;
        }

        if (!mBluetoothAdapter.isEnabled()) {
            if (!mBluetoothAdapter.enableNoAutoConnect()) {
                Log.e(TAG, "Error enabling Bluetooth.");
                return false;
            }
            mBluetoothEnabledByNfc = true;
            if (DBG) Log.d(TAG, "Queueing out transfer "
                    + Integer.toString(transferRecord.id));
        }

        mTransferManager = new BeamTransferManager(this, this, transferRecord, true);

        // register Beam status receiver
        mBeamStatusReceiver = new BeamStatusReceiver(this, mTransferManager);
        registerReceiver(mBeamStatusReceiver, mBeamStatusReceiver.getIntentFilter(),
                BeamStatusReceiver.BEAM_STATUS_PERMISSION, new Handler());

        mTransferManager.start();
        mTransferManager.updateNotification();
        return true;
    }

    private void invokeCompleteCallback(boolean success) {
        if (mCompleteCallback != null) {
            try {
                Message msg = Message.obtain(null, BeamManager.MSG_BEAM_COMPLETE);
                msg.arg1 = success ? 1 : 0;
                mCompleteCallback.send(msg);
            } catch (RemoteException e) {
                Log.e(TAG, "failed to invoke Beam complete callback", e);
            }
        }
    }

    @Override
    public void onTransferComplete(BeamTransferManager transfer, boolean success) {
        // Play success sound
        if (!success) {
            if (DBG) Log.d(TAG, "Transfer failed, final state: " +
                    Integer.toString(transfer.mState));
        }

        if (mBluetoothEnabledByNfc) {
            mBluetoothEnabledByNfc = false;
            mBluetoothAdapter.disable();
        }

        invokeCompleteCallback(success);
        stopSelf(mStartId);
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}