#-----------------------------------------------------------------------#
# Otbjectives:                                                          #  
#    - Measure Flammable Gas Concentration                              #                                                     
#    - Blink External LEDs - If Flammable Gas Conc. is at Toxic Level   #
#    - Measure Default Volts on PIN 05                                  #
#                                                                       #
# Author: Drop Bos                                                      #
# Created Date: May-05-2025                                             #
# Updated Date: Aug-09-2025                                             #
#                                                                       #
# License: Apache-2.0                                                   #
#                                                                       #
# Copyright © 2025. Drop Bos. All Rights Reserved.                      #
# ----------------------------------------------------------------------#


from utime import sleep
from machine import Pin, ADC


print("--------------------")
print("Detecting toxic gas level with MQ-2 gas sensor on ESP32-C3!")
print("MQ-2 gas sensor detects concentration of flammable gases in parts per million (ppm).") 
print("Flammable gases are mainly propane, butane, and methane.")


# define gas detector, leds and potentiometer
mq2_gas_sensor_A0 = ADC(3)
led_one = Pin(2, Pin.OUT)
potentiometer = ADC(4)


def separator():
    print("--------------------")

def get_gas_sensor_measurement(sensor=None):
    reading = sensor.read_u16()
    ppm = reading
    print(f"Flammable Gases Conc. Value is: {ppm} ppm")
    separator()
    return ppm

def adc_potentiometer_measurement(sensor=None):
    # 1. pico W
    # reading = sensor.read_u16()
    # print("sensor.read_u16() :",  reading)
    # conversion_factor = 3.3/65535

    # 2. esp32
    reading = sensor.read()
    conversion_factor =  3.3/4095
    voltage = reading * conversion_factor

    print(f"Potentiometer Voltage is: {voltage:.4f} volts")
    separator()    


def set_led_display(led_one=None, toxic_limit=None, blink_number=None, blink_seconds=None, ):
    for index in range(blink_number):
        value = get_gas_sensor_measurement(sensor=mq2_gas_sensor_A0)
        lel = toxic_limit #  Lower Explosive Limit (LEL) of 5% by volume
        if value >= lel:
            print("Alert: High Conc. of Flammable Gas is Detected!")
            separator()
            led_one.on()
            sleep(blink_seconds)
            led_one.off()
            sleep(blink_seconds)

separator()

while True:
    blink_number = 3
    blink_seconds = 0.5
    measurement_interval_seconds = 5
    toxic_limit = 50000 #  Lower Explosive Limit (LEL) of 5% by volume
    sleep(measurement_interval_seconds)
    set_led_display(
        led_one=led_one, 
        toxic_limit=toxic_limit,  
        blink_number=blink_number,
        blink_seconds=blink_seconds
    )
    adc_potentiometer_measurement(sensor=potentiometer)