#include <LiquidCrystal.h>

// initialize the library by associating any needed LCD interface pin
// with the arduino pin number it is connected to
 const int rs = 8, en = 9, d4 = 4, d5 = 5, d6 = 6, d7 = 7;
 LiquidCrystal lcd(rs, en, d4, d5, d6, d7);


// define custom characters - every character is 5x8 "pixels"
byte gauge_left[8] =   {  B11111,  B10000,  B10000,  B10000,  B10000,  B10000,  B10000,  B11111};  // left part of empty gauge    [ 
byte gauge_center[8] = {  B11111,  B00000,  B00000,  B00000,  B00000,  B00000,  B00000,  B11111};  // center part of empty gauge  _
byte gauge_right[8] =  {  B11111,  B00001,  B00001,  B00001,  B00001,  B00001,  B00001,  B11111};  // right part of empty gauge   ]
byte gauge_fill[8] =   {  B11111,  B11111,  B11111,  B11111,  B11111,  B11111,  B11111,  B11111};  // filled gauge                █

// int cpu_gauge;    // value for the CPU gauge
// int gpu_gauge;    // value for the GPU gauge
// char buffer[10];  // helper buffer to store C-style strings (generated with sprintf function)

byte bot_fuel_1[8] = {
  0b11111,
  0b10001,
  0b10001,
  0b11111,
  0b11101,
  0b11111,
  0b11111,
  0b11111,
};


byte bot_fuel_2[8] = {
  0b00000,
  0b00000,
  0b11000,
  0b01100,
  0b00100,
  0b00100,
  0b00100,
  0b11100,
};

void setup() 
{
  
  lcd.begin(16, 2);
  Serial.begin(9600);
  
  lcd.createChar(4,bot_fuel_1);
  lcd.createChar(5,bot_fuel_2);
  
                      // initialize the 16x2 lcd module
  lcd.createChar(0, gauge_left);    // create special character on position 0, gauge left    [ 
  lcd.createChar(1, gauge_center);  // create special character on position 1, gauge center  _
  lcd.createChar(2, gauge_right);   // create special character on position 2, gauge right   ]
  lcd.createChar(3, gauge_fill);    // create special character on position 3, gauge fill    █
               // enable backlight for the LCD module
}

void loop() {
 
  int value = analogRead(A0);   //đọc giá trị điện áp ở chân A0 
                                //(value luôn nằm trong khoảng 0-1023)
  Serial.println(value);        //xuất ra giá trị vừa đọc
  
  int voltage;
  voltage = map(value,0,1023,0,5000);   //chuyển thang đo của value 
                                        //từ 0-1023 sang 0-5000 (mV)
  Serial.println(voltage);              //xuất ra điện áp (đơn vị là mV)
  Serial.println();     //xuống hàng
 
  lcd.setCursor(0,0);
 int f;
  // 8 characters to draw the gauge --- ████___]
 float voltage_gauge_step = 5000.0/10.0;         // 100% is the maximum number, gauge is 8 characters wide, calculate one step  
  for (int j=0; j<10; j++) {
    if (voltage <= voltage_gauge_step*j) {    // value is smaller than step*i, draw "empty" character
         if (j==0)      
          {
           lcd.write(byte(0));    // [     first cell, opening bracket
           f=500;
            }     
         else if (j==9) 
          {
              lcd.write(byte(2));   // ]     last cell, closing bracket
            }     
         else           
           {
             lcd.write(byte(1));     // _     any other cell, lines top and bottom
            }     
        
       }
    else {                                  
         lcd.write(byte(3));         // value is bigger than step*i, draw filled character - █
         f=(j+1)*50+500;
          }  
  } 

  lcd.setCursor(0, 1);
  lcd.write(byte(4));
  lcd.write(byte(5));
  lcd.print(" Fuel: ");
  lcd.print(f);
  lcd.print(" l"); 
  delay(50);
}