#!/usr/bin/python
#--------------------------------------
#
# Title  : RayueloMatic
# Author : Roni Bandini - @RoniBandini 
# Date   : 09/28/2015
# Geo    : Buenos Aires, Argentina
# Brief	 : Python program to pick up Hopscotch novel chapters and display in the LCD with each pushbutton
#
# Thanks Matt Hawkins for the LCD control code
#
#--------------------------------------
 

#import
import RPi.GPIO as GPIO
import time
import sys
import random
 
# Define GPIO to LCD mapping
LCD_RS = 7
LCD_E  = 8
LCD_D4 = 25
LCD_D5 = 24
LCD_D6 = 23
LCD_D7 = 18
 
# Define some device constants
LCD_WIDTH = 16    # Maximum characters per line
LCD_CHR = True
LCD_CMD = False
LCD_LINE_1 = 0x80 # LCD RAM address for the 1st line
LCD_LINE_2 = 0xC0 # LCD RAM address for the 2nd line
 
# Timing constants
E_PULSE = 0.0005
E_DELAY = 0.0005

# button related 
GPIO.setmode(GPIO.BCM)
global time_stamp       

# GPIO 23 set up as input
GPIO.setup(21, GPIO.IN, pull_up_down=GPIO.PUD_UP)
 
def main():
  # Main program block
 
  GPIO.setmode(GPIO.BCM)       # Use BCM GPIO numbers
  GPIO.setup(LCD_E, GPIO.OUT)  # E
  GPIO.setup(LCD_RS, GPIO.OUT) # RS
  GPIO.setup(LCD_D4, GPIO.OUT) # DB4
  GPIO.setup(LCD_D5, GPIO.OUT) # DB5
  GPIO.setup(LCD_D6, GPIO.OUT) # DB6
  GPIO.setup(LCD_D7, GPIO.OUT) # DB7
 
  # Initialise display
  lcd_init()

  time_now = time.time() 
  time_stamp=time.time()
  timespressed=0
 
  # Populate list with random chapters
  L=list()
  x=0
  while not x==155:
   	r=random.randint (1,155)
   	if r not in L:
      		L.append (r)
		#print "Assigned ",r,
      		x+=1

  # Welcome text
  lcd_string("RayueloMatic",LCD_LINE_1)
  lcd_string("for Hopscotch ",LCD_LINE_2) 
  time.sleep(3) # 3 second delay
  lcd_string("by @RoniBandini",LCD_LINE_1)
  lcd_string("Press button",LCD_LINE_2) 
  time.sleep(3)

  while True:           
    # Wait for button
    GPIO.wait_for_edge(21, GPIO.FALLING)	  
    time_now = time.time()
    # use timestamp to avoid button multiple pressing
    if (time_now - time_stamp) >= 0.3:
                        # print list one by one
			print "\nReading chapter -> ",L[timespressed]								   			
			lcd_string("Chapter "+str(L[timespressed]),LCD_LINE_1)
			lcd_string("Press button",LCD_LINE_2)
			time.sleep(2)    			
			timespressed+=1
			# there are 155 chapters
    			if timespressed==155:					
				lcd_byte(0x01, LCD_CMD)
    				lcd_string("Book finished",LCD_LINE_1)
				lcd_string("@RoniBandini",LCD_LINE_2)
				time.sleep(3)					
   				sys.exit()
    time_stamp = time_now 
	     
   
          
def lcd_init():
  # Initialise display
  lcd_byte(0x33,LCD_CMD) # 110011 Initialise
  lcd_byte(0x32,LCD_CMD) # 110010 Initialise
  lcd_byte(0x06,LCD_CMD) # 000110 Cursor move direction
  lcd_byte(0x0C,LCD_CMD) # 001100 Display On,Cursor Off, Blink Off
  lcd_byte(0x28,LCD_CMD) # 101000 Data length, number of lines, font size
  lcd_byte(0x01,LCD_CMD) # 000001 Clear display
  time.sleep(E_DELAY)
 
def lcd_byte(bits, mode):
  # Send byte to data pins
  # bits = data
  # mode = True  for character
  #        False for command
 
  GPIO.output(LCD_RS, mode) # RS
 
  # High bits
  GPIO.output(LCD_D4, False)
  GPIO.output(LCD_D5, False)
  GPIO.output(LCD_D6, False)
  GPIO.output(LCD_D7, False)
  if bits&0x10==0x10:
    GPIO.output(LCD_D4, True)
  if bits&0x20==0x20:
    GPIO.output(LCD_D5, True)
  if bits&0x40==0x40:
    GPIO.output(LCD_D6, True)
  if bits&0x80==0x80:
    GPIO.output(LCD_D7, True)
 
  # Toggle 'Enable' pin
  lcd_toggle_enable()
 
  # Low bits
  GPIO.output(LCD_D4, False)
  GPIO.output(LCD_D5, False)
  GPIO.output(LCD_D6, False)
  GPIO.output(LCD_D7, False)
  if bits&0x01==0x01:
    GPIO.output(LCD_D4, True)
  if bits&0x02==0x02:
    GPIO.output(LCD_D5, True)
  if bits&0x04==0x04:
    GPIO.output(LCD_D6, True)
  if bits&0x08==0x08:
    GPIO.output(LCD_D7, True)
 
  # Toggle 'Enable' pin
  lcd_toggle_enable()
 
def lcd_toggle_enable():
  # Toggle enable
  time.sleep(E_DELAY)
  GPIO.output(LCD_E, True)
  time.sleep(E_PULSE)
  GPIO.output(LCD_E, False)
  time.sleep(E_DELAY)
 
def lcd_string(message,line):
  # Send string to display
 
  message = message.ljust(LCD_WIDTH," ")
 
  lcd_byte(line, LCD_CMD)
 
  for i in range(LCD_WIDTH):
    lcd_byte(ord(message[i]),LCD_CHR)
 
if __name__ == '__main__':
 
  try:
    main()
  except KeyboardInterrupt:
    pass
  finally:
    lcd_byte(0x01, LCD_CMD)
    lcd_string("Goodbye!",LCD_LINE_1)
    GPIO.cleanup()

