#include <LiquidCrystal.h> // is used to include outside libraries in your sketch

// LCD pin to Arduino
const int RS = 8; 
const int EN = 9; 
const int d4 = 4; 
const int d5 = 5; 
const int d6 = 6; 
const int d7 = 7; 


// create a variable of type LiquidCrystal
LiquidCrystal lcd (RS, EN, d4, d5, d6, d7); // LiquidCrystal lcd(8, 9, 4, 5, 6, 7); also works, without declaring the variables as above. The variant used in the code does not work without declaration.

void setup() { // put your setup code here, to run once:

  lcd.begin(16, 2); // initialize the interface on the LCD screen and specify the dimensions in width and height. 16 is the number of columns, 2 is the number of rows

  lcd.setCursor(0,0); // set the location at which subsequent text written to the LCD will be displayed; 0 is the starting point for column and row; in this case, the cursor is set in the first column and first row

  lcd.print("How do you feel?"); // print the text to the display. in this case, the text is on the first column and first row, as it was set earlier in lcd.setCursor(0,0);

  lcd.setCursor(0,1); // set the location at which subsequent text written to the LCD will be displayed; 0 is the starting point for column and row; in this case, the cursor is set in the first column and second row

  lcd.print("I feel:"); // print the text to the display. in this case, the text is on the first column and second row, as it was set earlier in lcd.setCursor(0,1);



 // make custom characters
 byte thrilled[8] = { // make a heart character of 8 bits
  0b00000,
  0b01010,
  0b11111,
  0b11111,
  0b11111,
  0b01110,
  0b00100,
  0b00000
};


byte happy[8] = { // make a smiley chararacter of 8 bits
  0b00000,
  0b00000,
  0b01010,
  0b00000,
  0b00000,
  0b10001,
  0b01110,
  0b00000
};

byte sad[8] = { // make a sad character of 8 bits
    0b00000,
    0b00000,
    0b01010,
    0b00000,
    0b00000,
    0b01110,
    0b10001,
    0b00000
};

byte surprised[8] = { // make a surprised character of 8 bits
    0b11011,
    0b00000,
    0b01010,
    0b00000,
    0b11111,
    0b10001,
    0b11111,
    0b00000
};

byte playful[8] = { // make a playful character of 8 bits
    0b00000,
    0b00000,
    0b01010,
    0b00000,
    0b00000,
    0b11111,
    0b10001,
    0b01110
};

  // create a new character
  lcd.createChar(0, thrilled); // create character 0 with the correspondent character data, which is named thrilled
  // create a new character
  lcd.createChar(1, happy); // create character 1 with the correspondent character data, which is named happy
  // create a new character
  lcd.createChar(2, sad); // create character 2 with the correspondent character data, which is named sad
  // create a new character
  lcd.createChar(3, surprised); // create character 3 with the correspondent character data, which is named surprised
  // create a new character
  lcd.createChar(4, playful); // create character 4 with the correspondent character data, which is named playful
}


void loop() { // put your main code here, to run repeatedly:
  int x; // declare x as an integer variable
  x = analogRead (0); // analog reading of pin A0
  lcd.setCursor(10,1); // set the cursor at the 11th column on the second row; take into account that 0 is the starting point
  if (x < 50) { // right button is pressed
    lcd.write(byte(0)); // right = thrilled
  }
  else if (x < 195) { // up button is pressed
    lcd.write (byte(1)); // up = happy
  }
  else if (x < 380){ // down button is pressed
    lcd.write (byte(2)); // down =  sad
  }
  else if (x < 590){ // left button is pressed
    lcd.write (byte(3)); // left = surprised
  }
  else if (x < 790){ // select button is pressed
    lcd.write (byte(4)); // select = playful
  }
}