#
# hello.load.45.py
#
# receive and display step response and sonar reading
# bike.sensor.py serial_port
#
# Neil Gershenfeld
# CBA MIT 10/29/10
#
# Adapted by Caroline Jaffe
# 11/23/2015
#
# (c) Massachusetts Institute of Technology 2010
# Permission granted for experimental and personal use;
# license for commercial sale available from MIT
#

from Tkinter import *
import serial

WINDOW = 600 # window size
eps = 0.5 # filter time constant
filter1 = 0.0 # filtered value
filter_sonar = 0
eps_sonar = 0.1 
bike_cnt = 0 # bike count
counter = 0 # counter of readings for debug purposes
reading_cnt = 0 # number of bike count readings
sonar_thresh = 100 # sonar sensor reading threshold for detecting bike
cap_thresh = 500 # capacitive touch sensor reading threshold for detecting bike
DEBUG_MODE = 0 # print debug statements if true
READ_TIME = 10 # number of readings below threshold for detecting bike

def idle(parent,canvas):
   global filter1, eps, filter_sonar, eps_sonar, bike_cnt, counter, reading_cnt, sonar_thresh, cap_thresh, DEBUG_MODE, READ_TIME
   #
   # idle routine
   #
   byte2 = 0
   byte3 = 0
   byte4 = 0
   ser.flush()
   #
   # find framing 
   #
   while 1:
      byte1 = byte2
      byte2 = byte3
      byte3 = byte4
      byte4 = ord(ser.read())
      if ((byte1 == 1) & (byte2 == 2) & (byte3 == 3) & (byte4 == 4)):
         break

   counter +=1
   if counter == 5:
      counter = 0
   #
   # read and plot
   #
   # Cap readings
   up_low1 = ord(ser.read())
   up_high1 = ord(ser.read())
   down_low1 = ord(ser.read())
   down_high1 = ord(ser.read())
   #
   # sonar readings
   low = ord(ser.read())
   high = ord(ser.read())
   #
   # cap values and canvas
   up_value1 = 256*up_high1 + up_low1
   down_value1 = 256*down_high1 + down_low1
   value1 = (up_value1 + (1023 - down_value1))/2.0
   filter1 = (1-eps)*filter1 + eps*value1
   x1 = int(.2*WINDOW + (.9-.2)*WINDOW*filter1/1023.0)
   if counter == 0 and DEBUG_MODE:
      print "cap: "
      print filter1
   canvas.itemconfigure("title1",text="Capacitive touch sensor reading:")
   canvas.itemconfigure("text1",text="%.1f"%filter1)
   canvas.coords('rect11',.2*WINDOW,.05*WINDOW,x1,.2*WINDOW)
   canvas.coords('rect12',x1,.05*WINDOW,.9*WINDOW,.2*WINDOW)
   #
   # Sonar values and canvas
   value = (256*high + low)
   filt = (1-eps)*filter_sonar+eps_sonar*value
   us = filt/8.0 # 8 MHz counter
   cm = us/58.0
   x = int(.2*WINDOW + (.9-.2)*WINDOW*cm/50)
   if counter == 0 and DEBUG_MODE:
      print "sonar: "
      print cm
   canvas.itemconfigure("title2",text="Sonar sensor reading:")
   canvas.itemconfigure("text",text="%.0f cm"%cm)
   canvas.coords('rect2',.2*WINDOW,.3*WINDOW,x,.45*WINDOW)
   canvas.coords('rect2',x,.3*WINDOW,.9*WINDOW,.45*WINDOW)
   #
   cm_int = int(cm)
   if cm_int == 14 and DEBUG_MODE:
      print "ERROR???"
      print cm
      print value
      print high
      print low

   # Bike count calculation and canvas
   if filter1 < cap_thresh and cm < sonar_thresh:
      reading_cnt += 1
      if reading_cnt == READ_TIME:
         bike_cnt += 1
         reading_cnt = 0
   canvas.itemconfigure("bike_text",text="Bike Count: %.0f"%bike_cnt)

   canvas.update()
   parent.after_idle(idle,parent,canvas)

#
#  check command line arguments
#
if (len(sys.argv) != 2):
   print "command line: bike.sensor.py serial_port"
   sys.exit()
port = sys.argv[1]
#
# open serial port
#
ser = serial.Serial(port,9600)
ser.setDTR()
#
# set up GUI
#
root = Tk()
root.title('bike.sensor.py (q to exit)')
root.bind('q','exit')
canvas = Canvas(root, width=WINDOW, height=.75*WINDOW, background='white')
#
canvas.create_text(.3*WINDOW,.03*WINDOW,text="1",font=("Helvetica", 24),tags="title1",fill="#0000b0")
canvas.create_text(.1*WINDOW,.125*WINDOW,text="1",font=("Helvetica", 24),tags="text1",fill="#0000b0")
canvas.create_rectangle(.2*WINDOW,.05*WINDOW,.3*WINDOW,.2*WINDOW, tags='rect11', fill='#b00000')
canvas.create_rectangle(.3*WINDOW,.05*WINDOW,.9*WINDOW,.2*WINDOW, tags='rect12', fill='#0000b0')

canvas.create_text(.3*WINDOW,.28*WINDOW,text="1",font=("Helvetica", 24),tags="title2",fill="#0000b0")
canvas.create_text(.1*WINDOW,.375*WINDOW,text="2",font=("Helvetica", 24),tags="text",fill="#0000b0")
canvas.create_rectangle(.2*WINDOW,.3*WINDOW,.3*WINDOW,.45*WINDOW, tags='rect1', fill='#b00000')
canvas.create_rectangle(.3*WINDOW,.3*WINDOW,.9*WINDOW,.45*WINDOW, tags='rect2', fill='#0000b0')

canvas.create_text(.2*WINDOW,.5*WINDOW,font=("Helvetica", 24),tags="bike_text",fill="#0000b0")
canvas.pack()
#
# start idle loop
#
root.after(100,idle,root,canvas)
root.mainloop()