#include <Wire.h>
#include <LiquidCrystal_I2C.h>


#define SET_POINT 25   // Punto de ajuste de temperatura en grados Celsius

int buf[10];
int temp = 0;
unsigned long int inValue;
const uint16_t tdsThreshold = 2000; // 12 bits 4096

// pins
// sda, scl -> 21 , 22
const uint8_t tdsPin = 32;
const uint8_t greenLedPin = 16;
const uint8_t yellowLedPin = 17;
const uint8_t redLedPin = 18;
const uint8_t relay1Pin = 19;
const uint8_t relay2Pin = 5;
const uint8_t relay3Pin = 4;
const uint8_t relay4Pin = 23;

// lcd
const uint8_t lcdAddr = 0x27;
LiquidCrystal_I2C lcd = LiquidCrystal_I2C(lcdAddr, 16, 2);

// parameters global vars
float temperature;
float ph;
float tds;

void setup(){
    Serial.begin(115200);

    // pin config
    pinMode(tdsPin, INPUT);
    pinMode(greenLedPin, OUTPUT);
    pinMode(yellowLedPin, OUTPUT);
    pinMode(redLedPin, OUTPUT);

    // lcd init
    lcd.init();
    lcdWelcomeMessage();
    delay(500);
}

void loop(){

    readAndCheckTDSLevel();
    showParametersOnLcd();
    delay(1000);
}


// ===========  Helper functions  =============
void lcdWelcomeMessage(){
    lcd.backlight();
    lcd.setCursor(0, 0);
    lcd.print(" Bienvenido a ");
    lcd.setCursor(0, 1);
    lcd.print(" Medidor pH ");
}

void readAndCheckTDSLevel(){
    // checks the current tds level
    tds = analogRead(tdsPin);
    Serial.println(tds);
    if (tds > tdsThreshold)
    {                                
        digitalWrite(redLedPin, HIGH); 
    }
    else
    {
        digitalWrite(redLedPin, LOW);
    }
}

void showParametersOnLcd(){
    lcd.clear();
    // PH
    lcd.setCursor(0, 0);
    lcd.print("Ph:");
    lcd.print(ph);
    lcd.print("   ");

    // temp
    lcd.setCursor(9, 0);
    lcd.print(" T:");
    lcd.print(temperature);
    lcd.print("°c");

    // TDS
    lcd.setCursor(8, 1);
    lcd.print("tds:");
    lcd.print(tds);
    lcd.print("   ");
}