# SmartGuard ESP32 - Multi-Sensor Alarm System
# Author: Santiago Pinedo

from machine import Pin, PWM, SoftI2C
from dht import DHT22
import time
import utime

dht_sensor = DHT22(Pin(4))

trig = Pin(5, Pin.OUT)
echo = Pin(18, Pin.IN)

pir        = Pin(19, Pin.IN)
btn_mute   = Pin(32, Pin.IN, Pin.PULL_UP)

led_green  = Pin(25, Pin.OUT)
led_red    = Pin(26, Pin.OUT)
led_yellow = Pin(27, Pin.OUT)

buzzer = PWM(Pin(23), freq=1000, duty=0)

i2c = SoftI2C(scl=Pin(22), sda=Pin(21))

# LCD I2C 
I2C_ADDR = 0x27

def lcd_send(data, mode):
    high = (data & 0xF0) | 0x08 | mode
    low  = ((data << 4) & 0xF0) | 0x08 | mode
    for nibble in [high, low]:
        i2c.writeto(I2C_ADDR, bytes([nibble | 0x04]))
        utime.sleep_us(1)
        i2c.writeto(I2C_ADDR, bytes([nibble & ~0x04]))
        utime.sleep_us(50)

def lcd_init():
    utime.sleep_ms(50)
    for cmd in [0x33, 0x32, 0x28, 0x0C, 0x06, 0x01]:
        lcd_send(cmd, 0)
        utime.sleep_ms(5)

def lcd_clear():
    lcd_send(0x01, 0)
    utime.sleep_ms(5)

def lcd_write(text, row=0, col=0):
    offsets = [0x00, 0x40]
    lcd_send(0x80 | (offsets[row] + col), 0)
    for ch in text:
        lcd_send(ord(ch), 1)

def lcd_print(line1="", line2=""):
    lcd_clear()
    lcd_write(line1[:16], 0)
    lcd_write(line2[:16], 1)

# Ultrasonic sensor 
def get_distance():
    trig.off()
    utime.sleep_us(2)
    trig.on()
    utime.sleep_us(10)
    trig.off()
    timeout = utime.ticks_us()
    while echo.value() == 0:
        if utime.ticks_diff(utime.ticks_us(), timeout) > 30000:
            return 999
    start = utime.ticks_us()
    while echo.value() == 1:
        if utime.ticks_diff(utime.ticks_us(), start) > 30000:
            return 999
    end = utime.ticks_us()
    return (utime.ticks_diff(end, start) * 0.0343) / 2

# Buzzer 
def beep(freq=1000, duration=200, times=1, muted=False):
    if muted:
        return
    for _ in range(times):
        buzzer.freq(freq)
        buzzer.duty(512)
        time.sleep_ms(duration)
        buzzer.duty(0)
        time.sleep_ms(100)

# LEDs off 
def leds_off():
    led_green.off()
    led_red.off()
    led_yellow.off()


event_log = []

def log_event(msg):
    timestamp = utime.ticks_ms() // 1000
    entry = f"[{timestamp}s] {msg}"
    event_log.append(entry)
    if len(event_log) > 5:
        event_log.pop(0)
    print(entry)

def print_log():
    print("\n===== EVENT LOG =====")
    for e in event_log:
        print(e)
    print("=====================\n")

#  Button mute 
muted        = False
mute_pressed = False

def check_mute_button():
    global muted, mute_pressed
    if btn_mute.value() == 0:
        if not mute_pressed:
            mute_pressed = True
            muted = not muted
            state = "MUTED" if muted else "UNMUTED"
            log_event(f"Buzzer {state} by button")
            lcd_print("Buzzer:", state)
            time.sleep_ms(500)
    else:
        mute_pressed = False

# Wilson beeps 
def wilson_panic():
    if muted:
        return
    for _ in range(5):
        buzzer.freq(3000)
        buzzer.duty(512)
        time.sleep_ms(80)
        buzzer.duty(0)
        time.sleep_ms(50)
        buzzer.freq(500)
        buzzer.duty(512)
        time.sleep_ms(80)
        buzzer.duty(0)
        time.sleep_ms(50)

def wilson_warning():
    if muted:
        return
    for _ in range(3):
        buzzer.freq(800)
        buzzer.duty(512)
        time.sleep_ms(300)
        buzzer.duty(0)
        time.sleep_ms(400)


lcd_init()
lcd_print("SmartGuard ESP32", "Starting...")
time.sleep(2)
beep(500, 100, 2)
log_event("System started")

alert_level = 0
cycle       = 0

print("=== SmartGuard ESP32 - Multi-Sensor Alarm System ===")


while True:
    cycle += 1
    alert_level = 0
    reasons = []

    check_mute_button()

    # Read temperature & humidity 
    try:
        dht_sensor.measure()
        temp = dht_sensor.temperature()
        hum  = dht_sensor.humidity()
    except:
        temp = 0
        hum  = 0

    
    dist = get_distance()

    
    motion = pir.value()

    
    if temp > 35:
        alert_level = 2
        reasons.append(f"HIGH TEMP {temp}C")
    elif temp > 28:
        alert_level = max(alert_level, 1)
        reasons.append(f"WARM {temp}C")

    if dist < 20:
        alert_level = 2
        reasons.append(f"TOO CLOSE {dist:.0f}cm")
        print("WILSON IS RIGHT HERE!!!")
        lcd_print("!! WILSON !!", "GET AWAY FROM ME")
        wilson_panic()

    elif dist < 50:
        alert_level = max(alert_level, 1)
        reasons.append(f"NEAR {dist:.0f}cm")
        print("Wilson is getting closer...")
        lcd_print("Wilson is coming", f"Dist:{dist:.0f}cm !!!")
        wilson_warning()

    if motion:
        alert_level = max(alert_level, 1)
        reasons.append("MOTION DETECTED")

    
    leds_off()

    if alert_level == 0:
        led_green.on()
        lcd_print(f"T:{temp}C H:{hum}%", f"Dist:{dist:.0f}cm  OK")
        if cycle % 10 == 0:
            log_event(f"OK | T:{temp}C D:{dist:.0f}cm")

    elif alert_level == 1:
        led_yellow.on()
        beep(800, 150, 1, muted)
        reason_str = " | ".join(reasons)
        lcd_print("!! CAUTION !!", reason_str[:16])
        log_event(f"CAUTION: {reason_str}")

    elif alert_level == 2:
        led_red.on()
        beep(2000, 300, 3, muted)
        reason_str = " | ".join(reasons)
        lcd_print("!!! DANGER !!!", reason_str[:16])
        log_event(f"DANGER: {reason_str}")

    
    if cycle % 20 == 0:
        print_log()

    
    if cycle % 5 == 0:
        mute_status = "MUTED" if muted else "ACTIVE"
        print(f"[Cycle {cycle}] Buzzer: {mute_status} | Alert level: {alert_level}")

    check_mute_button()
    time.sleep(1)