/*
  Photoresistor (LDR) Analog Demo

  Copyright (C) 2021 Uri Shaked.

  https://wokwi.com/arduino/projects/305193627138654786
*/

#include <LiquidCrystal_I2C.h>

#define LDR_PIN 2

// LDR Characteristics
const float GAMMA = 0.7;
const float RL10 = 50;

bool lazer1 = false;
bool lazer2 = false;
int state = 0;

int clients = 0;

LiquidCrystal_I2C lcd(0x27, 20, 4);

void setup() {
  pinMode(LDR_PIN, INPUT);

  lcd.init();
  lcd.backlight();
}

void loop() {
  int analogValue1 = analogRead(A0);
  float voltage1 = analogValue1 / 1024. * 5;
  float resistance1 = 2000 * voltage1 / (1 - voltage1 / 5);
  float lux1 = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance1, (1 / GAMMA));

  int analogValue2 = analogRead(A1);
  float voltage2 = analogValue2 / 1024. * 5;
  float resistance2 = 2000 * voltage2 / (1 - voltage2 / 5);
  float lux2 = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance2, (1 / GAMMA));


  if (lux1 < 101){
    lazer1 = true;
    if (!lazer2 && state==0){
      state = 1;
    }
  }
  if (lux2 < 101){
    lazer2 = true;
    if (!lazer1 && state==0){
      state = 2;
    }
  }

  if (lazer1 && lazer2 && (lux1 > 100) && (lux2 > 100)){
    if (state == 1){
      clients++;
    }
    if (state == 2){
      clients--;
    }
    lazer1 = false;
    lazer2 = false;
    state = 0;
  }



  lcd.setCursor(0, 0);
  lcd.print("Clients: ");
  lcd.print(clients);

  delay(100);
}