from machine import Pin, PWM, Timer
import time

LED_PIN    = 33
RED_PIN    = 25
GREEN_PIN  = 26
BLUE_PIN   = 27
BUTTON_PIN = 15

FREQ_HZ     = 1000     # PWM frequency: 1 kHz
DEBOUNCE_MS = 300      # Thoi gian chong nhieu nut nhan (ms)

MODE_NAMES = {
    1: "LED Blinking",
    2: "PWM Brightness Control",
    3: "RGB Color Cycling"
}
COLORS = [
    (100,   0,   0, "Red"),
    (  0, 100,   0, "Green"),
    (  0,   0, 100, "Blue"),
    (100, 100,   0, "Yellow"),
    (  0, 100, 100, "Cyan"),
    (100,   0, 100, "Magenta"),
    (100, 100, 100, "White"),
]
current_mode    = 1
mode_changed    = True      # True de khoi tao Mode 1 khi bat dau
last_press_time = 0
led_state       = 0         # Trang thai LED cho Mode 1
led_pwm   = None
red_pwm   = None
green_pwm = None
blue_pwm  = None
timer0    = Timer(0)
button    = Pin(BUTTON_PIN, Pin.IN, Pin.PULL_UP)

def percent_to_duty(pct):
    """Chuyen % (0-100) sang gia tri duty 10-bit (0-1023)."""
    return int(pct / 100 * 1023)

def button_isr(pin):
    """ISR: Doi che do khi nhan nut, co chong nhieu bang phan mem."""
    global current_mode, mode_changed, last_press_time

    now = time.ticks_ms()
    if time.ticks_diff(now, last_press_time) > DEBOUNCE_MS:
        last_press_time = now
        # Chuyen sang mode tiep theo: 1 -> 2 -> 3 -> 1 ...
        current_mode = current_mode % 3 + 1
        mode_changed = True

def timer_callback(t):
    """Timer callback: Toggle LED moi 1 giay (chi hoat dong o Mode 1)."""
    global led_state

    if current_mode == 1 and led_pwm is not None:
        led_state = not led_state
        try:
            led_pwm.duty(1023 if led_state else 0)
        except:
            pass

# Don dep tai nguyen
def cleanup_all():
    """Dung timer va tat tat ca LED/PWM."""
    global led_pwm, red_pwm, green_pwm, blue_pwm

    # Dung timer truoc de tranh callback truy cap PWM da bi huy
    try:
        timer0.deinit()
    except:
        pass

    # Tat va huy PWM LED don
    if led_pwm is not None:
        try:
            led_pwm.duty(0)
            led_pwm.deinit()
        except:
            pass
        led_pwm = None

    # Tat va huy PWM RGB
    for pwm_ref in ['red_pwm', 'green_pwm', 'blue_pwm']:
        obj = globals().get(pwm_ref)
        if obj is not None:
            try:
                obj.duty(0)
                obj.deinit()
            except:
                pass
            globals()[pwm_ref] = None

    red_pwm   = None
    green_pwm = None
    blue_pwm  = None

# Chuyen che do
def enter_mode(mode):
    """Chuyen sang che do moi: don dep cu, khoi tao moi, in thong bao."""
    global led_pwm, red_pwm, green_pwm, blue_pwm, led_state

    # Don dep che do truoc
    cleanup_all()
    print(f"Current Mode: {MODE_NAMES[mode]}")

    if mode == 1:
        # Mode 1: Timer toggle LED
        led_state = 0
        led_pwm = PWM(Pin(LED_PIN), freq=FREQ_HZ, duty=0)
        timer0.init(period=1000, mode=Timer.PERIODIC, callback=timer_callback)

    elif mode == 2:
        # Mode 2: PWM fading (xu ly trong main loop)
        led_pwm = PWM(Pin(LED_PIN), freq=FREQ_HZ, duty=0)

    elif mode == 3:
        # Mode 3: RGB cycling (xu ly trong main loop)
        red_pwm   = PWM(Pin(RED_PIN),   freq=FREQ_HZ, duty=0)
        green_pwm = PWM(Pin(GREEN_PIN), freq=FREQ_HZ, duty=0)
        blue_pwm  = PWM(Pin(BLUE_PIN),  freq=FREQ_HZ, duty=0)
    
# Dieu khien PWM cho Mode 2 va Mode 3
def pwm_fade():
    """Mode 2: Tang dan do sang 0% -> 100% roi giam 100% -> 0%."""
    STEP     = 5
    DELAY_MS = 20

    # Fade up: 0% -> 100%
    for brightness in range(0, 101, STEP):
        if current_mode != 2:
            return
        led_pwm.duty(percent_to_duty(brightness))
        time.sleep_ms(DELAY_MS)

    # Fade down: 100% -> 0%
    for brightness in range(100, -1, -STEP):
        if current_mode != 2:
            return
        led_pwm.duty(percent_to_duty(brightness))
        time.sleep_ms(DELAY_MS)

def rgb_cycle():
    HOLD_MS    = 50     # Kiem tra mode moi 50 ms
    HOLD_STEPS = 20     # 20 x 50 ms = 1 giay moi mau

    for r, g, b, name in COLORS:
        if current_mode != 3:
            return
        red_pwm.duty(percent_to_duty(r))
        green_pwm.duty(percent_to_duty(g))
        blue_pwm.duty(percent_to_duty(b))
        for _ in range(HOLD_STEPS):
            if current_mode != 3:
                return
            time.sleep_ms(HOLD_MS)

print()
print("*" * 50)
print("  Lab 3 - Exercise 3: Mini Project")
print("  Event-Driven LED Controller")
print("*" * 50)
print()
print(f"  LED      : GPIO {LED_PIN}")
print(f"  RGB LED  : GPIO {RED_PIN} (R), {GREEN_PIN} (G), {BLUE_PIN} (B)")
print(f"  Button   : GPIO {BUTTON_PIN} (PULL_UP)")
print(f"  Debounce : {DEBOUNCE_MS} ms")
print()
print("  Mode 1: LED Blinking (Timer 1s)")
print("  Mode 2: PWM Brightness Control")
print("  Mode 3: RGB Color Cycling")
print()
print("  Press button to switch mode.")
print()

# Gan ISR cho nut nhan (canh xuong = nhan nut)
button.irq(trigger=Pin.IRQ_FALLING, handler=button_isr)
try:
    while True:
        # Kiem tra co chuyen mode khong
        if mode_changed:
            mode_changed = False
            enter_mode(current_mode)

        # Thuc thi hanh vi cua mode hien tai
        if current_mode == 1:
            # Mode 1: Timer xu ly het, main loop chi doi
            time.sleep_ms(100)

        elif current_mode == 2:
            # Mode 2: Fading lien tuc
            pwm_fade()

        elif current_mode == 3:
            # Mode 3: Doi mau RGB lien tuc
            rgb_cycle()

except KeyboardInterrupt:
    cleanup_all()
    button.irq(handler=None)
    print("\nProgram stopped by user.")