from machine import Pin, I2C, PWM
import time
import ssd1306


TRIG_PIN = 5
ECHO_PIN = 18
BUTTON_PIN = 14
BUZZER_PIN = 27
BLUE_LED_PIN = 26  
YELLOW_LED_PIN = 25  
RED_LED_PIN = 33  
ORANGE_LED_PIN = 32 


NORMAL_LEVEL = 15
ALERT_LEVEL = 40 
WARNING_LEVEL = 80 
DANGER_LEVEL = 80 


i2c = I2C(0, scl=Pin(15), sda=Pin(4), freq=400000)
oled = ssd1306.SSD1306_I2C(128, 64, i2c)

trig = Pin(TRIG_PIN, Pin.OUT)
echo = Pin(ECHO_PIN, Pin.IN)
button = Pin(BUTTON_PIN, Pin.IN, Pin.PULL_UP)
buzzer = PWM(Pin(BUZZER_PIN), freq=1000, duty=0)
blue_led = Pin(BLUE_LED_PIN, Pin.OUT) 
yellow_led = Pin(YELLOW_LED_PIN, Pin.OUT) 
red_led = Pin(RED_LED_PIN, Pin.OUT)  
orange_led = Pin(ORANGE_LED_PIN, Pin.OUT) 

def get_distance():
    trig.value(1)
    time.sleep_us(10)
    trig.value(0)
    while echo.value() == 0:
        pulse_start = time.ticks_us()
    while echo.value() == 1:
        pulse_end = time.ticks_us()
    pulse_duration = pulse_end - pulse_start
    distance = (pulse_duration * 0.0343) / 2 
    return distance

def reset_system():
    global buzzer
    buzzer.duty(0)
    blue_led.value(1) 
    yellow_led.value(0) 
    orange_led.value(0) 
    red_led.value(0)  
    oled.fill(0)
    oled.text("System Reset", 0, 0)
    oled.show()

def main():
    reset_system()
    while True:
        distance = get_distance()
        
        if button.value() == 0: 
            reset_system()
            time.sleep(0.5)  
        
        oled.fill(0)
        oled.text("Height: {:.1f} cm".format(distance), 0, 0)
        
        if distance <= NORMAL_LEVEL:
            # Normal level
            blue_led.value(1) 
            yellow_led.value(0) 
            orange_led.value(0) 
            red_led.value(0)  
            buzzer.duty(0)  
            oled.text("Status: NORMAL", 0, 10)
        
        elif distance <= ALERT_LEVEL:
            # Alert level
            blue_led.value(0) 
            yellow_led.value(1) 
            orange_led.value(0) 
            red_led.value(0)  
            buzzer.duty(512)  
            oled.text("Status: ALERT", 0, 10)
            time.sleep(0.5)
            buzzer.duty(0)
        
        elif distance <= WARNING_LEVEL:
            # Warning level
            blue_led.value(0) 
            yellow_led.value(0) 
            orange_led.value(1) 
            red_led.value(0)  
            for _ in range(3): 
                buzzer.duty(512)
                time.sleep(0.2)
                buzzer.duty(0)
                time.sleep(0.2)
            oled.text("Status: WARNING", 0, 10)
        
        elif distance >= DANGER_LEVEL:
            # Danger level
            blue_led.value(0)  
            yellow_led.value(0)
            orange_led.value(0)
            red_led.value(1)
            for _ in range(5):  
                buzzer.duty(512)
                time.sleep(0.2)
                buzzer.duty(0)
                time.sleep(0.2)
            oled.text("Status: DANGER", 0, 10)
        
        oled.show()
        time.sleep(0.1)

if __name__ == "__main__":
    main()