from machine import Pin, ADC, I2C, PWM, time_pulse_us
import time
import dht
import math
from ssd1306 import SSD1306_I2C
from mpu6050 import MPU6050

# ── Pins ─────────────────────────────────────
TRIG = Pin(5, Pin.OUT)
ECHO = Pin(18, Pin.IN)

pot = ADC(Pin(34))
pot.atten(ADC.ATTN_11DB)

dht_sensor = dht.DHT22(Pin(4))
button = Pin(12, Pin.IN, Pin.PULL_UP)

red_led   = Pin(26, Pin.OUT)
green_led = Pin(27, Pin.OUT)

# ── Buzzer via PWM (replaces Pin) ────────────
buzzer = PWM(Pin(25))
buzzer.duty(0)          # start silent

# ── Servo ────────────────────────────────────
servo = PWM(Pin(14), freq=50)

# ── I2C (OLED + MPU6050) ─────────────────────
i2c  = I2C(0, scl=Pin(22), sda=Pin(21))
oled = SSD1306_I2C(128, 64, i2c)
mpu  = MPU6050(i2c)

# ── Thresholds ───────────────────────────────
LEVEL_SAFE   = 80
LEVEL_WATCH  = 50
LEVEL_DANGER = 30

RAIN_WATCH = 1500
RAIN_HEAVY = 3000

# ── Vibration detection ───────────────────────
WINDOW_SIZE = 5
VIB_THRESHOLD = 1.5
vibration_avg = 0.0

def get_vibration():
    ax = mpu.accel.x
    ay = mpu.accel.y
    az = mpu.accel.z - 1.0   # remove gravity
    return math.sqrt(ax*ax + ay*ay + az*az)

def moving_average(new, old):
    return (old * (WINDOW_SIZE - 1) + new) / WINDOW_SIZE

def vibration_detected():
    global vibration_avg
    current = get_vibration()
    vibration_avg = moving_average(current, vibration_avg)
    return vibration_avg > VIB_THRESHOLD

# ── Servo helper ──────────────────────────────
def set_servo(angle):
    duty = int((angle / 180) * 75 + 40)
    servo.duty(duty)

def set_outputs(red, green, angle):
    red_led.value(1 if red else 0)
    green_led.value(1 if green else 0)
    set_servo(angle)

# ── OLED helper ───────────────────────────────
def show_oled(line1, line2, line3=""):
    oled.fill(0)
    oled.text(line1, 0, 0)
    oled.text(line2, 0, 20)
    oled.text(line3, 0, 40)
    oled.show()

# ── Buzzer patterns (PWM-based, graduated) ────
#
#  SAFE      → silent
#  LIGHT     → soft low-pitch single beep (500 Hz, low duty)
#  WATCH     → medium-pitch double beep   (1000 Hz, mid duty)
#  DANGER    → high-pitch rapid triple    (2000 Hz, high duty)
#  SOS/VIB   → full alarm continuous      (3000 Hz, max duty)
#
def buzzer_beep(freq, duty, on_ms, off_ms, repeats=1):
    """Generic beep: sets freq+duty, waits on_ms, silences, waits off_ms."""
    buzzer.freq(freq)
    for _ in range(repeats):
        buzzer.duty(duty)
        time.sleep_ms(on_ms)
        buzzer.duty(0)
        time.sleep_ms(off_ms)

def buzzer_pattern(level):
    if level == "LIGHT":
        # Soft single beep — barely audible
        buzzer_beep(freq=500, duty=128, on_ms=120, off_ms=0, repeats=1)

    elif level == "WATCH":
        # Medium double beep — noticeable warning
        buzzer_beep(freq=1000, duty=300, on_ms=150, off_ms=100, repeats=2)

    elif level == "DANGER":
        # Loud rapid triple burst — urgent
        buzzer_beep(freq=2000, duty=600, on_ms=100, off_ms=70, repeats=3)

    elif level in ("SOS", "VIBRATION"):
        # Full alarm — max volume continuous burst
        buzzer_beep(freq=3000, duty=900, on_ms=100, off_ms=50, repeats=3)

    else:
        # Silent
        buzzer.duty(0)

# ── Boot sequence ────────────────────────────
show_oled("Flood Monitor", "Starting...", "")
time.sleep(0.5)

set_outputs(True, False, 0)
time.sleep(0.3)
set_outputs(False, True, 0)
time.sleep(0.5)
show_oled("System Ready", "Monitoring...", "")

# ── Distance ─────────────────────────────────
def get_distance():
    TRIG.off()
    time.sleep_us(2)
    TRIG.on()
    time.sleep_us(10)
    TRIG.off()

    duration = time_pulse_us(ECHO, 1, 30000)
    
    if duration < 0:
        return 999  # no signal / safe default

    distance = (duration * 0.034) / 2
    return distance


# ── Button Toggle System ───────────────────
last_button_state = 1
btnSOS = False

# ── Main loop ─────────────────────────────────
show_weather = False

while True:
    try:
        dist    = get_distance()
        pot_val = pot.read()

        dht_sensor.measure()
        temp = dht_sensor.temperature()
        hum  = dht_sensor.humidity()

        tilt   = vibration_detected()

        current_state = button.value()

        if last_button_state == 1 and current_state == 0:
            btnSOS = not btnSOS
            time.sleep_ms(20)

        last_button_state = current_state

        rain_pct = int((pot_val / 4095) * 100)

        print("Dist:{:.1f} Rain:{}% T:{}C H:{}% Vib:{}".format(
              dist, rain_pct, temp, hum, tilt))

        # ── Priority 1: Manual SOS ────────────
        if btnSOS:
            set_outputs(True, False, 90)
            show_oled("  !!! SOS !!!", "  EVACUATE NOW", "")
            buzzer_pattern("SOS")
            time.sleep(0.2)
            continue

        # ── Priority 2: Ground vibration ──────
        if tilt:
            set_outputs(True, False, 90)
            show_oled("   LANDSLIDE!", "   Vibration!", "   Evacuate!")
            buzzer_pattern("VIBRATION")
            time.sleep(0.3)
            continue

        # ── Priority 3: Flood danger ──────────
        if 0 < dist < LEVEL_DANGER:
            set_outputs(True, False, 90)
            show_oled("FLOOD DANGER!", "Water:{:.1f}cm".format(dist), "Evacuate!")
            buzzer_pattern("DANGER")
            time.sleep(0.3)
            continue

        rising     = (0 < dist < LEVEL_SAFE)
        heavy_rain = pot_val > RAIN_HEAVY
        light_rain = pot_val > RAIN_WATCH

        # ── Priority 4: Watch / heavy rain ────
        if rising or heavy_rain:
            set_outputs(False, False, 45)
            msg = "   Heavy Rain" if heavy_rain else "Water rising"
            show_oled("    WARNING", msg, " Water:{:.1f}cm".format(dist))
            buzzer_pattern("WATCH")
            time.sleep(0.7)
            continue

        # ── Priority 5: Light rain ────────────
        if light_rain:
            set_outputs(False, False, 20)
            show_oled(
                "   Light Rain",
                "rain:{}% ".format(rain_pct),
                "T:{}C  H:{}%".format(temp, hum)

                )

            buzzer_pattern("LIGHT")
            time.sleep(0.8)
            continue

        # ── All clear ─────────────────────────
        set_outputs(False, True, 0)
        buzzer.duty(0)

        if show_weather:
            show_oled("Temp:{}C".format(temp),
                      "Humidity:{}%".format(hum),
                      "All Clear")

        else:
            show_oled("All Clear",
                      "Water:{:.1f}cm".format(dist), "")

        show_weather = not show_weather
        time.sleep(2)

    except Exception as e:
        print("Error:", e)
        show_oled("SYSTEM ERROR", str(e)[:16], "")
        buzzer.duty(0)
        time.sleep(1)