// simple project using Arduino UNO and 16x2 character display to display smooth gauge,
// created by upir, 2022
// youtube channel: https://www.youtube.com/upir_upir

// FULL TUTORIAL: https://youtu.be/ZzIGHiHObYw
// GAUGE IN 11 MINUTES TUTORIAL: https://youtu.be/upE17NHrdPc

// Links related to this project:
// Arduino UNO - https://s.click.aliexpress.com/e/_AXDw1h
// Arduino breadboard prototyping shield - https://s.click.aliexpress.com/e/_ApbCwx
// 16x2 displays with IIC - https://s.click.aliexpress.com/e/_9Hl3JV
// 16x2 display with RGB backlight - https://s.click.aliexpress.com/e/_9wgpeb
// original sketch from YWROBOT - https://wokwi.com/arduino/libraries/LiquidCrystal_I2C/HelloWorld
// character creator - https://tusindfryd.github.io/screenduino/
// another character creator - https://maxpromer.github.io/LCD-Character-Creator/
// sprintf explanation - https://www.programmingelectronics.com/sprintf-arduino/
// custom characters simplest project - https://wokwi.com/projects/294395602645549578
// Arduino I2C scanner - https://playground.arduino.cc/Main/I2cScanner/
// 16x2 available characters - https://docs.wokwi.com/parts/wokwi-lcd1602#font
// Bitwise Operators in GIFs - https://blog.wokwi.com/bitwise-operators-in-gifs/
// Bitwise operators Arduino documentation - https://www.arduino.cc/reference/en/language/structure/bitwise-operators/bitshiftleft/



#include <LiquidCrystal_I2C.h>     // if you don´t have I2C version of the display, use LiquidCrystal.h library instead

LiquidCrystal_I2C lcd(0x27, 16, 2); 
// set the LCD address to 0x27 for a 16 chars and 2 line display
//LiquidCrystal_I2C lcd(0x3f,16,2);    // set the LCD address to 0x3f for a 16 chars and 2 line display
// if you don´t know the I2C address of the display, use I2C scanner first (https://playground.arduino.cc/Main/I2cScanner/)

int screenWidth = 16;
int screenHeight = 2;
int stringStart = 0;
int stringEnd = 0;
int scrollCursor = screenWidth;
String line1 = "Tecle * ";
String line2 = "Sistema de controle de acesso.";  //scroll this line



void setup()
{
  lcd.init();                       // initialize the 16x2 lcd module
  lcd.backlight();                  // enable backlight for the LCD module

  lcd.begin(screenWidth, screenHeight);
}


void loop()
{
  // print the string on the display

  lcd.setCursor (0, 1); // Seting the cursor on first row
  lcd.print (line1);
  lcd.setCursor (scrollCursor, 0); // Seting the cursor on first row and (scrolling from left to right)
  lcd.print(line2.substring(stringStart, stringEnd));  // To print line1 first character "T"
  //Serial.println (line2.substring(stringStart, stringEnd));


  delay (250);
  //lcd.clear(); // clear message
  lcd.setCursor(0, 0);
  lcd.print("                ");

  if (stringStart == 0 && scrollCursor > 0)
  {

    scrollCursor --; // moving cursor from 16 to 0
    stringEnd ++;
  }   //character T, H, I, S ...
  // it wil print out character from 0 to 15 (entire length of the screen)

  else if (stringStart == stringEnd)
  {

    stringStart = stringEnd = 0;  // start oll over again
    scrollCursor = screenWidth;

  }


  else if (stringEnd == line2.length() and scrollCursor == 0)
  {

    stringStart ++;

  } // if reaches to end character


  else // it will print out character from (1 to 16) to end character
  {

    stringStart ++;
    stringEnd ++;

  }

}