import time, utime
from machine import Pin, PWM, I2C
from ssd1306 import SSD1306_I2C
import framebuf, sys


# Utilities Functions
def hex2rgb(hex):
    return tuple([int(hex[0:2],16),int(hex[2:4],16),int(hex[4:6],16)])

def int8_2_u16(x):
  return x * 65535 // 255

# OLED Setup
def init_i2c(scl_pin, sda_pin):
    # Initialize I2C device
    i2c_dev = I2C(1, scl=Pin(scl_pin), sda=Pin(sda_pin), freq=200000)
    i2c_addr = [hex(ii) for ii in i2c_dev.scan()]
    
    if not i2c_addr:
        print('No I2C Display Found')
        sys.exit()
    else:
        print("I2C Address      : {}".format(i2c_addr[0]))
        print("I2C Configuration: {}".format(i2c_dev))
    
    return i2c_dev
def displayGreeting(oled):
    oled.fill(0)
    oled.text("Hello", 5, 5)
    oled.text("Use keypad to", 5, 15)
    oled.text("pick color", 5, 25)
    oled.show()
def displayText(oled, text):
    oled.fill(0)
    oled.text("Hex Code:", 5, 5)
    oled.text(text, 5, 15)
    oled.show()

# PWM Setup
RED = 0; GREEN = 1; BLUE = 2
pwms = [PWM(Pin(13)),PWM(Pin(14)),PWM(Pin(15))]
[pwm.freq(1000) for pwm in pwms]

def turnOff():
    pwms[RED].duty_u16(0); pwms[GREEN].duty_u16(0); pwms[BLUE].duty_u16(0)
    time.sleep(0.1)

# Keypad Setup
KEY_R1 = 9; KEY_R2 = 8; KEY_R3 = 7; KEY_R4 = 6
KEY_C1 = 5; KEY_C2 = 4; KEY_C3 = 3; KEY_C4 = 2
KEYPAD_ROWS = [9,8,7,6]; KEYPAD_COLUMNS = [5,4,3,2]
MATRIX_KEYS = [ ['1','2','3','A'], ['4','5','6','B'], ['7','8','9','C'], ['*','0','#','D']]
rowPins = []; colPins = []
for x in range(0, 4):
    rowPins.append(Pin(KEYPAD_ROWS[x], Pin.OUT)); rowPins[x].value(1)
    colPins.append(Pin(KEYPAD_COLUMNS[x], Pin.IN, Pin.PULL_DOWN)); colPins[x].value(0)

def readKey():
    key = None
    for row in range(4):
        for col in range(4):
            rowPins[row].high()
            if (colPins[col].value()) == 1:
                key = MATRIX_KEYS[row][col]
                utime.sleep(0.1)
        rowPins[row].low()
    return key



def displayColor(oled,hexString):
    red, green, blue = hex2rgb(hexString)

    pwms[RED].duty_u16(int8_2_u16(red))
    pwms[GREEN].duty_u16(int8_2_u16(green))
    pwms[BLUE].duty_u16(int8_2_u16(blue))

    oled.fill(0)
    oled.text("Displaying:", 5, 5)
    oled.text(hexString, 5, 15)
    oled.show()

pix_res_x = 128
pix_res_y = 64
oled = SSD1306_I2C(pix_res_x, pix_res_y, init_i2c(27, 26))
hexString = '';

displayGreeting(oled)
while True:
    key = None
    key = readKey()

    if key != None:
        if key.isdigit():
            hexString = hexString + key
            displayText(oled,hexString)
        elif key == '*':
            if len(hexString) == 6:
                displayColor(oled,hexString)
        else:
            hexString = hexString[:- 1]
            displayText(oled,hexString)