# P3H - Intelligent Pedestrian Crossing Traffic Light
from machine import Pin, PWM
import time

time.sleep(0.1)

# Pins
car_green  = Pin(15, Pin.OUT)
car_yellow = Pin(14, Pin.OUT)
car_red    = Pin(13, Pin.OUT)

rgb_red   = PWM(Pin(10))
rgb_green = PWM(Pin(12))
rgb_blue  = PWM(Pin(11))

for pwm in (rgb_red, rgb_green, rgb_blue):
    pwm.freq(1000)

button = Pin(16, Pin.IN, Pin.PULL_UP)

# Timing (seconds)
GREEN_TIME     = 5
YELLOW_TIME    = 2.5
RED_TIME       = 7.5
WALK_TIME      = 4
BLINK_DURATION = 2
BLINK_INTERVAL = 0.25

# Colors (common cathode: 65535 = full on)
WHITE     = (65535, 65535, 65535)
OFF       = (0, 0, 0)
DONT_WALK = (65535, 0, 0)  # red channel only

def set_ped(r, g, b):
    rgb_red.duty_u16(r)
    rgb_green.duty_u16(g)
    rgb_blue.duty_u16(b)

def all_off():
    car_green.off()
    car_yellow.off()
    car_red.off()
    set_ped(*OFF)

all_off()

ped_request = False

while True:
    # Green phase
    car_green.on()
    set_ped(*OFF)

    start = time.ticks_ms()
    while time.ticks_diff(time.ticks_ms(), start) < GREEN_TIME * 1000:
        if button.value() == 0:
            ped_request = True
            time.sleep_ms(200)
            break
        time.sleep_ms(50)

    car_green.off()

    # Yellow phase
    car_yellow.on()
    time.sleep(YELLOW_TIME)
    car_yellow.off()

    # Red + pedestrian phase
    car_red.on()

    set_ped(*WHITE)
    time.sleep(WALK_TIME)

    for _ in range(int(BLINK_DURATION / BLINK_INTERVAL)):
        set_ped(*DONT_WALK)
        time.sleep(BLINK_INTERVAL)
        set_ped(*OFF)
        time.sleep(BLINK_INTERVAL)

    set_ped(*DONT_WALK)

    remaining = RED_TIME - WALK_TIME - BLINK_DURATION
    if remaining > 0:
        time.sleep(remaining)

    car_red.off()
    ped_request = False