# this software is licensed under the GPL v3 license.
# for further information see document GPL v3.txt

# include packages
import serial
import re
import math
from tkinter import *

# create and configure serial port object
ser = serial.Serial()
ser.port = 'COM3'   # e.g. on Windows 'COM3' and on Linux '/dev/ttyUSB0'
ser.baudrate = 115200
ser.rtscts = True

#print(ser) # debug only: show current serial port configuration

try:
    ser.open()
except Exception as ex:
    print("Failed to open serial port:", type(ex).__name__, "-", ex)
    exit(1)

print('Serial port successfully opened')

# create an instance of tkinter frame
win = Tk()

# define the geometry of window
win.geometry("750x500")

# set the resizable property to false
win.resizable(False, False)

# change titel of window
win.title('Visualization of azimuth and elevation angles')

# create a canvas object
c = Canvas(win, width=750, height=350)
c.pack()

# oval settings
rad = 150

pos_1x = 200
pos_1y = 200

pos_2x = pos_1x + 2 * rad + pos_1x - rad + 25
pos_2y = 200

def draw_pointer(angle, x, y):
    angle_rad = math.radians(angle)
    side_x = math.cos(angle_rad) * rad
    side_y = math.sin(angle_rad) * rad
    c.create_line(x, y, x + side_x, y + side_y, fill="green", width=3)

def draw_guideline(angle, x, y, factor, width):
    angle_rad = math.radians(angle)
    side_x = math.cos(angle_rad) * rad
    side_y = math.sin(angle_rad) * rad
    short_x = side_x * factor
    short_y = side_y * factor
    c.create_line(x+short_x, y+short_y, x+side_x, y+side_y, fill="red", width=width)
    
# text labels
label_azimuth = Label(win, text='-', bg='white')
label_azimuth.place(x=pos_1x-55, y=pos_1y + rad + 55)
label_elevation = Label(win, text='-', bg='white')
label_elevation.place(x=pos_2x-55, y=pos_2y + rad + 55)

label_90_azimuth = Label(win, text='90°', bg='white')
label_90_azimuth.place(x=pos_1x + rad + 4, y=pos_1y - 9)
label_90_elevation = Label(win, text='90°', bg='white')
label_90_elevation.place(x=pos_2x - 7, y=pos_2y - rad - 23)

label_0_azimuth = Label(win, text='0°', bg='white')
label_0_azimuth.place(x=pos_1x - 4, y=pos_1y - rad - 23)
label_0_elevation = Label(win, text='0°', bg='white')
label_0_elevation.place(x=pos_2x - rad - 20, y=pos_2y - 9)

label_n90_azimuth = Label(win, text='-90°', bg='white')
label_n90_azimuth.place(x=pos_1x - rad - 30, y=pos_1y - 9)
label_n90_elevation = Label(win, text='-90°', bg='white')
label_n90_elevation.place(x=pos_2x - 15, y=pos_2y + rad + 5)

# win.mainloop()
angle_azimuth = 0
angle_elevation = 0

while True:
    # draw an oval in the canvas
    c.create_oval(pos_1x - rad, pos_1y - rad, pos_1x + rad, pos_1y + rad, fill = 'white')
    c.create_oval(pos_2x - rad, pos_2y - rad, pos_2x + rad, pos_2y + rad, fill = 'white')
    
    # draw guidelines in the oval
    factor = 0.9
    for i in range(0, 360, 360//24):
        draw_guideline(i, pos_1x, pos_1y, factor, 1)
        draw_guideline(i, pos_2x, pos_2y, factor, 1)
    
    factor = 0.7
    for i in range(0, 360, 360//8):
        draw_guideline(i, pos_1x, pos_1y, factor, 2)
        draw_guideline(i, pos_2x, pos_2y, factor, 2)
        
    try:
        data = ser.readline().decode('utf-8') # built string from byte array
    except UnicodeDecodeError as ex:
        # it seems that decode() fails sometimes at startup
        # to prevent this move the C209 tag for a few seconds before startup
        # retry to read next data
        continue
    m = re.search(r'^\+UUDF:[^,]*,[^,]*,([0-9-]+),([0-9-]+),[^,]*,[^,]*,[^,]*,[^,]*,[^,]*,[^,]*$', data)
    if m is not None:
        angle_azimuth, angle_elevation = m.groups()
        label_azimuth.config(text="Azimuth angle = " + angle_azimuth)
        label_elevation.config(text="Elevation angle = " + angle_elevation)
        #print(angle_azimuth, angle_elevation) # debug only: print the azimuth and elevation angles
        angle_azimuth = int(angle_azimuth) + 270
        angle_elevation = int(angle_elevation) + 180
        #print(data) # debug only: print the data that we received over the serial port
    
    draw_pointer(angle_azimuth, pos_1x, pos_1y)
    draw_pointer(angle_elevation, pos_2x, pos_2y)
    
    win.update_idletasks()
    win.update()
    try:
        c.delete("all")
    except TclError as ex:
        # when the window gets closed via X button we get a TclError here
        # so we exit the main loop
        break
        
ser.close()
print("Serial port successfully closed")