import machine
import time
import neopixel

# ============================================================
#  HEARTBEAT CLASS (smooth fading version)
# ============================================================

class HeartbeatFadeNeoPixel:
    def __init__(self, neopixel_obj, pixel_index=0, color=(255, 0, 0),
                 max_brightness=100, step=2, interval_ms=20):
        self.np = neopixel_obj
        self.index = pixel_index
        self.color = color
        self.max_brightness = max_brightness
        self.step = step           # how fast brightness changes
        self.interval = interval_ms

        self.brightness = 0
        self.direction = 1         # 1 = going up, -1 = going down
        self.last_time = time.ticks_ms()

    def apply_brightness(self, c, level):
        r, g, b = c
        factor = level / 100
        return (int(r * factor), int(g * factor), int(b * factor))

    def update(self):
        now = time.ticks_ms()
        if time.ticks_diff(now, self.last_time) >= self.interval:
            self.last_time = now

            # Update brightness
            self.brightness += self.direction * self.step

            # Bounce at limits
            if self.brightness >= self.max_brightness:
                self.brightness = self.max_brightness
                self.direction = -1

            if self.brightness <= 0:
                self.brightness = 0
                self.direction = 1

            # Apply brightness
            self.np[self.index] = self.apply_brightness(self.color, self.brightness)
            self.np.write()


# ============================================================
#  NEOPIXEL SETUP
# ============================================================

# 3-LED strip on GP17
STRIP_PIN = 17
STRIP_LEDS = 3
strip = neopixel.NeoPixel(machine.Pin(STRIP_PIN), STRIP_LEDS)

# Single heartbeat pixel on GP28
SINGLE_PIN = 28
single = neopixel.NeoPixel(machine.Pin(SINGLE_PIN), 1)

# ============================================================
#  BUTTONS (GP20, GP21, GP22)
# ============================================================

button_pins = [20, 21, 22]
buttons = [machine.Pin(pin, machine.Pin.IN, machine.Pin.PULL_UP)
           for pin in button_pins]

# ============================================================
#  COLOR PALETTE
# ============================================================

colors = [
    (0,   0,   0),     # Off
    (255,   0,   0),   # Red
    (0,   255,   0),   # Green
    (0,     0, 255),   # Blue
    (255, 255,   0),   # Yellow
    (0,   255, 255),   # Cyan
    (255,   0, 255),   # Magenta
    (255, 128,   0),   # Orange
    (128,   0, 255),   # Purple
    (255,  20, 147),   # Pink
    (128, 255,   0),   # Lime
    (255, 255, 255),   # White
]

# ============================================================
#  STATE FOR PIXELS 0–2 (BUTTON-CONTROLLED)
# ============================================================

color_index = [0, 0, 0]
brightness = [50, 50, 50]
last_state = [1, 1, 1]
press_time = [0, 0, 0]

# ============================================================
#  HEARTBEAT PIXEL CONFIG (smooth fade)
# ============================================================

FLASH_COLOR_INDEX = 1      # Choose from palette
FLASH_MAX_BRIGHTNESS = 20 # Peak brightness for fade
FLASH_STEP = 0.5             # Speed of fade
FLASH_INTERVAL_MS = 30     # Lower = smoother animation

heartbeat = HeartbeatFadeNeoPixel(
    neopixel_obj=single,
    pixel_index=0,
    color=colors[FLASH_COLOR_INDEX],
    max_brightness=FLASH_MAX_BRIGHTNESS,
    step=FLASH_STEP,
    interval_ms=FLASH_INTERVAL_MS
)

# ============================================================
#  HELPERS
# ============================================================

def apply_brightness(color, level):
    r, g, b = color
    factor = level / 100
    return (int(r * factor), int(g * factor), int(b * factor))

def update_strip():
    for i in range(STRIP_LEDS):
        strip[i] = apply_brightness(colors[color_index[i]], brightness[i])
    strip.write()

# ============================================================
#  INITIAL STATE
# ============================================================

update_strip()

# ============================================================
#  MAIN LOOP
# ============================================================

while True:
    now = time.ticks_ms()

    # --------------------------------
    # BUTTON HANDLING FOR 3-LED STRIP
    # --------------------------------
    for i in range(3):
        state = buttons[i].value()

        if last_state[i] == 1 and state == 0:
            press_time[i] = now

        if last_state[i] == 0 and state == 1:
            duration = time.ticks_diff(now, press_time[i])

            if duration > 500:
                brightness[i] += 10
                if brightness[i] > 100:
                    brightness[i] = 10
            else:
                color_index[i] = (color_index[i] + 1) % len(colors)

            update_strip()
            time.sleep_ms(200)

        last_state[i] = state

    # ----------------------------
    # SMOOTH HEARTBEAT UPDATE
    # ----------------------------
    heartbeat.update()

    time.sleep_ms(10)