package nextrek.services;

import java.util.ArrayList;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.util.Log;

public abstract class ServiceConnector {

    final static private String TAG = "ServiceConnector";

    /**
     * Command to the service to register a client, receiving callbacks
     * from the service. The Message's replyTo field must be a Messenger of
     * the client where callbacks should be sent.
     */
    static final int MSG_REGISTER_CLIENT = 1;

    /**
     * Command to the service to unregister a client, ot stop receiving callbacks
     * from the service. The Message's replyTo field must be a Messenger of
     * the client as previously given with MSG_REGISTER_CLIENT.
     */
    static final int MSG_UNREGISTER_CLIENT = 2;

    /**
     * Command to service to add a photo to the queue. This can be sent to the
     * service to supply a new value, and will be sent by the service to
     * any registered clients with the new value.
     */
    static final int MSG_SEND = 3;

    /** Keeps track of all current registered clients. */
    static ArrayList<Messenger> mClients = new ArrayList<Messenger>();

    public ServiceConnector() {
    }

    /**
     * Handler of incoming messages from clients.
     */

    /**
     * Target we publish for clients to send messages to IncomingHandler.
     */
    final Handler mHandler = new Handler() {

        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_REGISTER_CLIENT:
                    // don't add duplicates!!!
                    synchronized (mClients) {

                        if (!mClients.contains(msg.replyTo)) {
                            mClients.add(msg.replyTo);
                        }
                    }

                    break;
                case MSG_UNREGISTER_CLIENT:
                    synchronized (mClients) {
                        mClients.remove(msg.replyTo);
                    }
                    break;

                case MSG_SEND:
                    try {
                        Bundle bundle = (Bundle) msg.obj;
                        onHandleRequest(bundle);
                    } catch (Exception e) {
                        Log.e(TAG, e.toString());
                    }
                    break;
                default:
                    super.handleMessage(msg);
            }
        }
    };

    final Messenger mMessenger = new Messenger(mHandler);

    public IBinder getBinder() {
        return mMessenger.getBinder();
    }

    public void sendProgress(Bundle bundle) {
        for (int i = mClients.size() - 1; i >= 0; i--) {
            try {
                Message msg = Message.obtain(null, ClientConnector.MSG_WORK_PROGRESS, bundle);
                mClients.get(i).send(msg);
            } catch (RemoteException e) {
                // The client is dead. Remove it from the list;
                // we are going through the list from back to front
                // so this is safe to do inside the loop.
                mClients.remove(i);
            }
        }
    }

    protected abstract void onHandleRequest(Bundle bundle);
}