# Exercise
import lcddriver
import RPi.GPIO as GPIO	# For Digital I/O
import os		# For System Shutdown

from time import gmtime, localtime, sleep, strftime

# Instantiate display
lcd = lcddriver.lcd()

# Initialize display
lcd.lcd_clear()

# Initialize GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(17, GPIO.IN, pull_up_down = GPIO.PUD_UP)

# Persistent part of display (Lines 1-3)
lcd.lcd_display_string(" HAM RADIO STATION", 1)
lcd.lcd_display_string("    W A 4 E F S", 2)
lcd.lcd_display_string("                    ",3)

# Variable part of display (Line 4 and Shutdown message)
while (True): # Forever ...
  if (GPIO.input(17) == 1): # Shutdown button pressed
    # Shutdown message
    lcd.lcd_display_string("** Shutting down! **", 1)
    lcd.lcd_display_string("Please wait 1 minute", 2)
    lcd.lcd_display_string("before disconnecting", 3)
    lcd.lcd_display_string("power.              ", 4)

    sleep(1) # Make sure display has painted
    os.system("sudo shutdown --poweroff now")
    quit()

# Enable either Universal Time or Local Time by commenting-out the other
  lcd.lcd_display_string(strftime("%d %b %Y %H:%M:%S", gmtime()),4)
# lcd.lcd_display_string(strftime("%d %b %Y %H:%M:%S", localtime()),4)

  sleep(.05)