#Michelle

from machine import Pin, ADC
import time
import os

#Setup Pin Connections
onboard_led = Pin(25, Pin.OUT)

first_red_led = Pin(14, Pin.OUT)
first_green_led = Pin(12, Pin.OUT)
first_yellow_led = Pin(9, Pin.OUT)

second_red_led = Pin(6, Pin.OUT)
second_green_led = Pin(4, Pin.OUT)
second_yellow_led = Pin(1, Pin.OUT)

buzzer = Pin(17, Pin.OUT)
buzzer.value(0)

gas_sensor = ADC(Pin(27))

#safe limit for gas concentration
safe_limit = 30 #Gas level baseline for danger

#Create a file to save gas level readings
filename = "gas_reading.csv"
if filename not in os.listdir():
    with open(filename, "w") as f:
        f.write("Seconds, gas_level\n")


#Setup Counter and Reading Interval
seconds_passed = 0      #Counts since program/pico start
reading_interval = 1    #time between each gas reading


#warm up Gas Sensor
print("Warming up the gas sensor for 60 seconds...")
for seconds in range(1, 61):
    seconds_passed += 1
    print("Warm up: {} seconds".format(seconds_passed))

    #Blink onboard LED during warm-up
    onboard_led.value(1)
    time.sleep(0.5)
    onboard_led.value(0)
    time.sleep(0.5)
    onboard_led.value(1)
    time.sleep(0.5)

print ("Warm up complete!!!")
onboard_led.value(1)


# Gas sensor reading
print("Now reading gas levels every {} seconds".format( reading_interval))
while True:
    # read gas level and convert it to percentage
    raw_value = gas_sensor.read_u16() #Lowest level is 0 and highest level is 65535

    #convert raw value to percentage
    gas_level = (raw_value / 65535) *100
    gas_percentage = round(gas_level, 1) #Round gas level in 1 decimal place

    #Print gas levels in precentage and the seconds_passed
    print("Gas Level: {}% at {} seconds".format(gas_percentage, seconds_passed))
    
    with open(filename, "a") as f:
        f.write("{},%\n".format(seconds_passed,gas_percentage))


#Main Logic of Smart Gas Detection Machine
    #When gas_precentage is above the safe limit
    if gas_percentage >= 21:
        first_red_led.value(1)
        second_red_led.value(1)
        time.sleep(1)
        first_red_led.value(0)
        second_red_led.value(0)
        time.sleep(0.5)
        first_red_led.value(0)
        second_red_led.value(0)
        buzzer.value(1)
        time.sleep(1)
        buzzer.value(0)
        time.sleep(1)
        buzzer.value(1)
    
    elif gas_percentage >= 11 and gas_percentage <= 20:
        first_yellow_led.value(1)
        second_yellow_led.value(1)
        time.sleep(1)
        first_yellow_led.value(0)
        second_yellow_led.value(0)
        time.sleep(0.5)
        first_yellow_led.value(0)
        second_yellow_led.value(0)
       
    # When gas_percentage is below safe limit
    else:
        first_green_led(1)
        second_green_led(1)
        time.sleep(1)
        first_green_led.value(0)
        second_green_led.value(0)
        time.sleep(1)
        first_green_led(1)
        second_green_led(1)
        time.sleep(1)
        first_green_led(0)
        second_green_led(0)

        first_red_led.value(0)
        second_red_led.value(0)
        buzzer.value(0)

    seconds_passed += reading_interval
    time.sleep(reading_interval)