/*
 * Class uses the RXTX Library for Serial Communication
 * to send, receive and encode Strings from an Arduino
 *
 * done by Laurid Meyer
 * 28.04.2012
 *
 * http://www.lauridmeyer.com
 */
 
import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;
 
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
 
public class RXTX implements SerialPortEventListener{
        SerialPort serialPort;
            /** The port we're normally going to use. */
        private static final String PORT_NAMES[] = {
                "/dev/tty.usbserial-A9007UX1", // Mac OS X
                "/dev/ttyUSB0", // Linux
                "COM11", // Windows
                };
        /** Buffered input stream from the port */
        private InputStream input;
        /** The output stream to the port */
        private OutputStream output;
        /** Milliseconds to block while waiting for port open */
        private static final int TIME_OUT = 2000;
        /** Default bits per second for COM port. */
        private static final int DATA_RATE = 9600;
 
        private String inputBuffer="";
 
        public void initialize() {
            CommPortIdentifier portId = null;
            Enumeration portEnum = CommPortIdentifier.getPortIdentifiers();
 
            // iterate through, looking for the port
            while (portEnum.hasMoreElements()) {
                CommPortIdentifier currPortId = (CommPortIdentifier) portEnum.nextElement();
                for (String portName : PORT_NAMES) {
                    if (currPortId.getName().equals(portName)) {
                        portId = currPortId;
                        break;
                    }
                }
            }
 
            if (portId == null) {
                System.out.println("Could not find COM port.");
                return;
            }else{
                System.out.println("Found your Port");
            }
 
            try {
                // open serial port, and use class name for the appName.
                serialPort = (SerialPort) portId.open(this.getClass().getName(),TIME_OUT);
 
                // set port parameters
                serialPort.setSerialPortParams(DATA_RATE,
                        SerialPort.DATABITS_8,
                        SerialPort.STOPBITS_1,
                        SerialPort.PARITY_NONE);
 
                // open the streams
                input = serialPort.getInputStream();
                output = serialPort.getOutputStream();
 
                // add event listeners
                serialPort.addEventListener(this);
                serialPort.notifyOnDataAvailable(true);
 
            } catch (Exception e) {
                System.err.println(e.toString());
            }
        }
 
        /**
         * This should be called when you stop using the port.
         * This will prevent port locking on platforms like Linux.
         */
        public synchronized void close() {
            if (serialPort != null) {
                serialPort.removeEventListener();
                serialPort.close();
            }
        }
 
        /**
         * This Method can be called to print a String
         * to the serial connection
         */
        public synchronized void sendString(String msg){
            try {
                msg+='\n';//add a newline character
                output.write(msg.getBytes());//write it to the serial
                output.flush();//refresh the serial
                System.out.print("<- "+msg);//output for debugging
            } catch (Exception e) {
                System.err.println(e.toString());
            }
        }
 
        /**
         * This Method is called when a command is recieved
         * and needs to be encoded
         */
        private synchronized void encodeCommand(String com){
            if(com.indexOf("s:")==0){//checks if the String starts with s for set
                String id=com.substring(com.indexOf("s:")+2, com.indexOf(","));//remove the s, and store the "p1"
                String value=com.substring(com.indexOf(",")+1, com.length());//store everything after the ","
                if(id.equals("p1") && !value.equals("")){//if it's my poti1 and it sends a value
                    String myValue="s:s1,"+value;//set the value to my servo1
                    sendString(myValue);//and send it via the serial
                }else{
                    System.out.println("not correct values");
                }
            }
        }
 
        /**
         * This Method is called when Serialdata is recieved
         */
        public synchronized void serialEvent (SerialPortEvent oEvent) {
            if (oEvent.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
                try {
                    int available = input.available();
                    for(int i=0;i<available;i++){//read all incoming characters
                        int receivedVal=input.read();//store it into an int (because of the input.read method
                        if(receivedVal!=10 && receivedVal!=13){//if the character is not a new line "\n" and not a carriage return
                            inputBuffer+=(char)receivedVal;//store the new character into a buffer
                        }else if(receivedVal==10){//if it's a new line character
                            System.out.println("-> "+inputBuffer);//output for debugging
                            encodeCommand(inputBuffer);//call the method to encode the recieved command
                            inputBuffer="";//clear the buffer
                        }
                    }
                } catch (Exception e) {
                    System.err.println(e.toString());
                }
            }
        }
 
        public static void main(String[] args) throws Exception {
            RXTX main = new RXTX();
            main.initialize();
            System.out.println("Started");
        }
    }