#include <Wire.h> // include the Wire library for I2C communication
#include "LiquidCrystal_I2C.h"
//#include LiquidCrystal_I2C lcd(0x27, 16, 2);

LiquidCrystal_I2C lcd(0x27,16,2);

#define POT_PIN A3 // pin for the potentiometer
#define RELAY_PIN A0 // pin for the relay
#define BUTTON_A_PIN A1 // pin for button A
#define BUTTON_B_PIN A2 // pin for button B

#define CYCLE_DURATION 50 // cycle duration in milliseconds

int cycleRatio = 0; // variable to store the cycle ratio
bool cycleActive = false; // variable to store if the cycle is active or not

void setup() {
  lcd.begin();
  lcd.backlite();
  pinMode(POT_PIN, INPUT); // set potentiometer pin as input
  pinMode(RELAY_PIN, OUTPUT); // set relay pin as output
  pinMode(BUTTON_A_PIN, INPUT); // set button A pin as input
  pinMode(BUTTON_B_PIN, INPUT); // set button B pin as input
}

void loop() {
  // read the potentiometer value and map it to a range of 0-100
  cycleRatio = map(analogRead(POT_PIN), 0, 1023, 0, 100);

  // check if button A is pressed
  if (digitalRead(BUTTON_A_PIN) == HIGH) {
    // if cycle is not active, activate it
    if (!cycleActive) {
      cycleActive = true;
    }
  }

  // check if button B is pressed
  if (digitalRead(BUTTON_B_PIN) == HIGH) {
    // if cycle is active, stop it
    if (cycleActive) {
      cycleActive = false;
    }
  }

  // if cycle is active, turn on the relay for the specified cycle ratio
  if (cycleActive) {
    digitalWrite(RELAY_PIN, HIGH);
    delay(cycleRatio * CYCLE_DURATION / 100); // delay for the specified cycle ratio
    digitalWrite(RELAY_PIN, LOW);
    delay((100 - cycleRatio) * CYCLE_DURATION / 100); // delay for the remaining cycle ratio
  }

  // display the cycle ratio and cycle status on the LCD screen
  displayLCD(cycleRatio, cycleActive);
}

// function to display the cycle ratio and cycle status on the LCD screen
void displayLCD(int ratio, bool active) {
  // convert the cycle ratio to a string
  String ratioString = String(ratio) + "%";

  // create a string to display the cycle status
  String statusString;
  if (active) {
    statusString = "ON";
  } else {
    statusString = "OFF";
  }

  // send the commands to the LCD screen to display the strings
  LCD.setCursor(1, 0);
  LCD.print(ratioString); // display the cycle ratio
  LCD.setCursor(1, 2);
  LCD.print(statusString); // display the cycle status
 
}

// code sourced from https://www.arduino.cc/en/Tutorial/LiquidCrystalI2C
// and https://www.arduino.cc/en/Tutorial/AnalogReadSerial