CommService.java

/*
 * (C) Copyright 2015 by fr3ts0n <erwin.scheuch-heilig@gmx.at>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 */

package com.fr3ts0n.ecu.gui.androbd;

import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;

import com.fr3ts0n.ecu.prot.obd.ElmProt;

import org.apache.log4j.Logger;

/**
 * Abstract communication service
 */
public abstract class CommService
{
	/** communication media */
	public enum MEDIUM
	{
		BLUETOOTH,    ///< Bluetooth device
		USB,          ///< USB device
		NETWORK       ///< Network/WIFI device
	}

	/** media type selection */
	public static MEDIUM medium = MEDIUM.BLUETOOTH;

	/** Constants that indicate the current connection state */
	public enum STATE
	{
		NONE,           ///< we're doing nothing
		LISTEN,         ///< listening for incoming connections
		CONNECTING,     ///< initiating an outgoing connection
		CONNECTED,      ///< connected to a remote device
		OFFLINE         ///< we are offline
	}

	// Debugging
	protected static final String TAG = "CommService";

	public static final Logger log = Logger.getLogger(TAG);

	public static final ElmProt elm = new ElmProt();

	protected Context mContext;
	protected Handler mHandler = null;
	protected STATE mState;

	/**
	 * Constructor. Prepares a new Communication session.
	 */
	public CommService()
	{
		super();
		// mAdapter = MainActivity.mBluetoothAdapter;
		mState = STATE.NONE;
	}

	/**
	 * Constructor. Prepares a new Communication session.
	 *
	 * @param handler A Handler to send messages back to the UI Activity
	 */
	public CommService(Handler handler)
	{
		this();
		mHandler = handler;
	}

	/**
	 * Constructor. Prepares a new Bluetooth Communication session.
	 *
	 * @param context The UI Activity Context
	 * @param handler A Handler to send messages back to the UI Activity
	 */
	public CommService(Context context, Handler handler)
	{
		this(handler);
		mContext = context;
	}

	/**
	 * Set the current state of the chat connection
	 *
	 * @param state An integer defining the current connection state
	 */
	protected synchronized void setState(STATE state)
	{
		log.debug("setState() " + mState + " -> " + state);
		mState = state;

		// Give the new state to the Handler so the UI Activity can update
		mHandler.obtainMessage(MainActivity.MESSAGE_STATE_CHANGE, state).sendToTarget();
	}

	/**
	 * Return the current connection state.
	 */
	public synchronized STATE getState()
	{
		return mState;
	}

	/**
	 * Start the chat service. Specifically start AcceptThread to begin a session
	 * in listening (server) mode. Called by the Activity onResume()
	 */
	public abstract void start();

	/**
	 * Stop all threads
	 */
	public abstract void stop();

	/**
	 * Write to the output device in an unsynchronized manner
	 *
	 * @param out The bytes to write
	 */
	public abstract void write(byte[] out);

	/**
	 * start connection to specified device
	 *
	 * @param device The device to connect
	 * @param secure Socket Security type - Secure (true) , Insecure (false)
	 */
	public abstract void connect(Object device, boolean secure);

	/**
	 * Indicate that the connection attempt failed and notify the UI Activity.
	 */
	protected void connectionFailed()
	{
		stop();
		// set new state offline
		setState(STATE.OFFLINE);
		// Send a failure message back to the Activity
		Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
		Bundle bundle = new Bundle();
		bundle.putString(MainActivity.TOAST, mContext.getString(R.string.unabletoconnect));
		msg.setData(bundle);
		mHandler.sendMessage(msg);
	}

	/**
	 * Indicate that the connection was lost and notify the UI Activity.
	 */
	protected void connectionLost()
	{
		stop();
		// set new state offline
		setState(STATE.OFFLINE);
		// Send a failure message back to the Activity
		Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
		Bundle bundle = new Bundle();
		bundle.putString(MainActivity.TOAST, mContext.getString(R.string.connectionlost));
		msg.setData(bundle);
		mHandler.sendMessage(msg);
	}

	/**
	 * Indicate that the connection was established and notify the UI Activity.
	 */
	protected void connectionEstablished(String deviceName)
	{
		// Send the name of the connectionEstablished device back to the UI Activity
		Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_DEVICE_NAME);
		Bundle bundle = new Bundle();
		bundle.putString(MainActivity.DEVICE_NAME, deviceName);
		msg.setData(bundle);
		mHandler.sendMessage(msg);

		// set state to connected
		setState(STATE.CONNECTED);
	}
}