#!/usr/bin/env python3
########################################################################
# Filename    : ButtonLED.py
# Description : Controlling an led by button.
# Author      : freenove
# modification: 2018/08/02
########################################################################
import RPi.GPIO as GPIO
import time

ledPin = 11    # define the ledPin
buttonPin = 12    # define the buttonPin

def setup():
    print ('Program is starting...')
    GPIO.setmode(GPIO.BOARD)       # Numbers GPIOs by physical location
    GPIO.setup(ledPin, GPIO.OUT)   # Set ledPin's mode is output
    GPIO.setup(buttonPin, GPIO.IN, pull_up_down=GPIO.PUD_UP)    # Set buttonPin's mode is input, and pull up to high level(3.3V)

def loop():
    led = GPIO.input(ledPin)
    btnWas = GPIO.input(buttonPin)
    t = time.clock()
    while True:
        btn = GPIO.input(buttonPin)
        if btn != btnWas :
            # remember button
            btnWas = btn
            print('button: %d' %btn)

            if btn == GPIO.LOW :
                if time.clock() - t < 0.2 :
                    print ("button: blink")
                    for i in range(1, 5):
                        GPIO.output(ledPin, GPIO.HIGH)
                        time.sleep(0.5)
                        GPIO.output(ledPin, GPIO.LOW)
                        time.sleep(0.5)


                t = time.clock()

                # change LED
                if led == GPIO.LOW :
                    led = GPIO.HIGH
                else :
                    led = GPIO.LOW
                GPIO.output(ledPin, led)

def destroy():
    GPIO.output(ledPin, GPIO.LOW)     # led off
    GPIO.cleanup()                     # Release resource

if __name__ == '__main__':     # Program start from here
    setup()
    try:
        loop()
    except KeyboardInterrupt:  # When 'Ctrl+C' is pressed, the child program destroy() will be  executed.
        destroy()