#!/usr/bin/env python

# Some of this monitor was made possible with help from those at:
# http://shallowsky.com/blog/hardware/ardmonitor.html
# http://code.activestate.com/recipes/134892/


import sys
import threading
import time
import Queue
import serial


class PythonSerialMonitor():
    def __init__(self):
        self.windows = False
        self.unix = False
        self.fd = None
        self.old_settings = None

        try:
            # Windows
            import msvcrt
            self.windows = True
        except ImportError:
            # Unix
            import sys, tty, termios
            self.fd = sys.stdin.fileno()
            self.old_settings = termios.tcgetattr(self.fd)
            tty.setcbreak(self.fd)
            self.unix = True

        self.input_queue = Queue.Queue()
        self.stop_queue = Queue.Queue()
        self.pause_queue = Queue.Queue()

        self.input_thread = threading.Thread(target=self.add_input, args=(self.input_queue,self.stop_queue,self.pause_queue,))
        self.input_thread.daemon = True
        self.input_thread.start()

    def getch(self):
        if self.unix:
            import sys, tty, termios
            try:
                tty.setcbreak(sys.stdin.fileno())
                ch = sys.stdin.read(1)
            finally:
                termios.tcsetattr(self.fd, termios.TCSADRAIN, self.old_settings)
            return ch
        if self.windows:
            import msvcrt
            return msvcrt.getch()

    def cleanUp(self):
        if self.unix:
            import sys, tty, termios
            termios.tcsetattr(self.fd, termios.TCSADRAIN, self.old_settings)

    def add_input(self, input_queue, stop_queue, pause_queue):
        while True:
            input_queue.put(self.getch())
            if not pause_queue.empty():
                if pause_queue.get() == 'pause':
                    while True:
                        if not pause_queue.empty():
                            if pause_queue.get() == 'resume':
                                break
            if not stop_queue.empty():
                if stop_queue.get() == 'stop':
                    break

    def run(self):
        baud = 9600
        baseports = ['/dev/ttyUSB', '/dev/ttyACM', 'COM', '/dev/tty.usbmodem1234']
        self.ser = None

        while not self.ser:
            for baseport in baseports:
                if self.ser:
                    break
                for i in xrange(0, 64):
                    try:
                        port = baseport + str(i)
                        self.ser = serial.Serial(port, baud, timeout=1)
                        print("Monitor: Opened " + port + '\r')
                        break
                    except:
                        self.ser = None
                        pass

            if not self.ser:
                print("Monitor: Couldn't open a serial port.")
                print("Monitor: Press \'enter\' to try again or \'esc\' to exit.")
                while True:
                    if not self.input_queue.empty():
                        keyboardInput = self.input_queue.get()
                        if ord(keyboardInput) == 27:
                            self.stop_queue.put('stop')
                            self.cleanUp()
                            sys.exit(1)
                        else:
                            # Pressing any key other than 'esc' will continue the monitor
                            break

        self.ser.flushInput()

        while True:
            if not self.input_queue.empty():
                keyboardInput = self.input_queue.get()
                print("Keyboard: " + keyboardInput)
                self.ser.write(keyboardInput)
                if ord(keyboardInput) == 27:
                    self.stop_queue.put('stop')
                    self.cleanUp()
                    sys.exit(1)

            # Check for Teensy output:
            try:
                bytesToRead = self.ser.inWaiting() # get the amount of bytes available at the input queue
                if bytesToRead:
                    line = self.ser.read(bytesToRead) # read the bytes
                    print("Teensy: " + line.strip())
            except IOError:
                # Manually raise the error again so it can be caught outside of this method
                raise IOError()


psm = PythonSerialMonitor()

while True:
    try:
            psm.run()
    except serial.SerialException:
        print ("Monitor: Disconnected (Serial exception)")
    except IOError:
        print ("Monitor: Disconnected (I/O Error)")
    except KeyboardInterrupt:
        print ("Monitor: Keyboard Interrupt. Exiting Now...")
        sys.exit(1)