# import necessary modules
import sys
import csimpl
if sys.version < '3':
   from Tkinter import *
   iimport tkMessageBox
else:
   from tkinter import *
   from tkinter import messagebox

BRINKY_RITE = 0
global leds            # a series of eight button widgets
global numLeds

# a callback for changing the text value of a led button
def hndlChange(event):
   # make certain that entered text is black
   event.widget["foreground"] = "black"
   # decide on the next character after a left button mouse click
   if event.widget["text"] == "OFF":
       event.widget["text"] = "ON"
   else:
       event.widget["text"] = "OFF"

# a callback for the send button
def hndlSubmit(nee, receiverId):
   # assemble the message
   outToken = BRINKY_RITE
   outValues = 0
   for num in range(numLeds):
       if leds[num]["text"] == "ON":
           outValues |= (1 << num)

   # load the message to be sent to the Arduino sketch
   nee.packMsg(nee.BIN, "hb", outToken, outValues)

   # send the message
   retVal = nee.send(receiverId)
   if retVal == -1:
       if sys.version < '3':
          tkMessageBox.showerror("Error", nee.whatsMyError())
       else:
           messagebox.showerror("Error", nee.whatsMyError())
       sys.exit(-1)

# operational start of the program
# check command line
if len(sys.argv) == 1:
   rName = "ARDUINO"
elif len(sys.argv) == 2:
   rName = sys.argv[1] + ":" + "ARDUINO"
else:
   print("Incorrect command line")
   sys.exit(-1)

# initialize some variables
numLeds = 8
leds = [None] * numLeds

# make an instance of Simpl
nee = csimpl.Simpl( "EIGHT_LEDS", 1024)

# name locate the C program SIMPL receiver
receiverId = nee.nameLocate("sys.argv[1]:ARDUINO")
if receiverId == -1:
   err = nee.whatsMyError() + ": is the receiver program running?"
   if sys.version < '3':
      tkMessageBox.showerror("Error", err)
   else:
      messagebox.showerror("Error", err)
   sys.exit(-1)

# initialize Tk for graphics
root = Tk()
rowframe = Frame(root)
rowframe.pack(fill=BOTH)
for num in range(numLeds):
   leds[num] = Button(rowframe,  borderwidth=2, relief=SOLID, justify=CENTER, bg="Yellow", fg="Black", text="OFF", font=("Times", 12, "bold"),    width=3)
   leds[num].bind("<Button-1>", hndlChange)
   leds[num].pack(side=LEFT)

# the bottom frame of buttons
rowframe = Frame(root)
rowframe.pack(fill=BOTH)
Button(rowframe, justify=CENTER, text="Send", font=('Times', 12, 'bold'), command=(lambda: hndlSubmit(nee, receiverId))).pack()

# handle user input
root.mainloop()