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

// House Icon
byte housechar1[8]={B00000, B00001, B00011, B00011, //Row 0, Col 0
                  B00111, B01111, B01111, B11111,};
byte housechar2[8]={B11111, B11111, B11100, B11100, //Row 1, Col 0
                  B11100, B11100, B11100, B11100,};
byte housechar3[8]={B00000, B10010, B11010, B11010, //ROW 0, Col 1
                  B11110, B11110, B11110, B11111,};
byte housechar4[8]={B11111, B11111, B11111, B10001, //Row 1, Col 1
                    B10001, B10001, B11111, B11111,};

// Initialize the LCD
LiquidCrystal_I2C lcd(0x27,  16, 2);

// INPUT:     
int TDButPin = 13;   // Temp Up Button connected to pin 13
int TUButPin = 14;   // Temp Down Button connected to pin 13
// OUTPUT:
int redLEDPin = 9;   // Red  LED,    connected to digital pin 9
int bluLEDPin = 10;  // Blue LED,    connected to digital pin 10
int redBUTPin = 11;  // Red  Button, connected to digital pin 11
int bluBUTPin = 12;  // Blue Button, connected to digital pin 12
// Program Variables
int temp = 72;
int redVal = 0;
int bluVal = 0;
int redOldValue = LOW; 
int bluOldValue = LOW;
int tuVal = 0;
int tdVal = 0;
int tuOldValue = LOW;
int tdOldValue = LOW;

void setup() {
  // initialize lcd screen
  lcd.init();
  lcd.backlight();
    // create and add thermostat icon
  lcd.createChar(1,housechar1);
  lcd.createChar(2,housechar2);
  lcd.createChar(3,housechar3);
  lcd.createChar(4,housechar4);
  lcd.setCursor(0,0);
  lcd.write(1);
  lcd.setCursor(0,1);
  lcd.write(2);
  lcd.setCursor(1,0);
  lcd.write(3);
  lcd.setCursor(1,1);
  lcd.write(4);
    // temp and mode
  lcd.setCursor(4, 0);
  lcd.print("Mode: Off");
  lcd.setCursor(4, 1);
  lcd.print("Temp:   ");
  lcd.print((char)223);
  lcd.print("F");

  // initialize LEDs
  pinMode(redLEDPin, OUTPUT);
  pinMode(bluLEDPin, OUTPUT); 
  // initialize the buttons
  pinMode(redBUTPin, INPUT);
  pinMode(bluBUTPin, INPUT);
  pinMode(TDButPin, INPUT);
  pinMode(TUButPin, INPUT);
}

void loop() {
  // display the temp on the LCD
  lcd.setCursor(10, 1);
  lcd.print("  ");
  lcd.setCursor(10, 1);
  lcd.print(temp);

  // read the value of buttons
  int redNewValue = digitalRead(redBUTPin);
  int bluNewValue = digitalRead(bluBUTPin);
  int tuNewValue = digitalRead(TUButPin);
  int tdNewValue = digitalRead(TDButPin);

  // check if the red button was pressed
  if (redNewValue == HIGH && redOldValue == LOW) {
    Serial.println("Red button pressed.");
    if (redVal == HIGH) { // if red LED is ON, turn it OFF
      analogWrite(redLEDPin, LOW);
      redVal = LOW;

      // display updated mode
      lcd.setCursor(10, 0);
      lcd.print("         ");
      lcd.setCursor(10, 0);
      lcd.print("Off");
    } else { // if red LED is OFF, turn it ON and turn blue LED off
      analogWrite(redLEDPin, HIGH);
      analogWrite(bluLEDPin, LOW);
      redVal = HIGH;
      bluVal = LOW;

      // display updated mode
      lcd.setCursor(10, 0);
      lcd.print("         ");
      lcd.setCursor(10, 0);
      lcd.print("Heat");
    }
  }

  // check if the blue button was pressed
  if (bluNewValue == HIGH && bluOldValue == LOW) { 
    Serial.println("Blue button pressed.");
    if (bluVal == HIGH) { // if blue LED is ON, turn it OFF
      analogWrite(bluLEDPin, LOW);
      bluVal = LOW;

      // display updated mode
      lcd.setCursor(10, 0);
      lcd.print("         ");
      lcd.setCursor(10, 0);
      lcd.print("Off");
    } else { // if blue LED is OFF, turn it ON and turn red LED off
      analogWrite(bluLEDPin, HIGH);
      analogWrite(redLEDPin, LOW);
      bluVal = HIGH;
      redVal = LOW;

      // display updated mode
      lcd.setCursor(10, 0);
      lcd.print("         ");
      lcd.setCursor(10, 0);
      lcd.print("Cool");
    }
  }

  // check if the temp up button was pressed
  if (tuNewValue == HIGH && tuOldValue == LOW) {
    Serial.println("Temp Up button pressed.");
    ++temp;
  }

  // check if the temp down button was pressed
  if (tdNewValue == HIGH && tdOldValue == LOW) {
    Serial.println("Temp Down button pressed.");
    --temp;
  }

  // update button states
  redOldValue = redNewValue;
  bluOldValue = bluNewValue;
  tuOldValue  = tuNewValue;
  tdOldValue  = tdNewValue;

  // slow down for debouncing
  delay(100);
}