#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN WIDTH 128
#define SCREEN HEIGHT 64
#define OLED_RESET 4
Adafruit_SSD1306 display(128,64, &Wire, OLED_RESET);

int p1 = random(0,100);
int p2 = random(0,100);
int p3 = random(0,100);

void setup() {

   // by default, we'll generate the high voltage from the 3.3v line internally! (neat!)
   display.begin(SSD1306_SWITCHCAPVCC, 0x3C);  // initialize with the I2C addr 0x3D (for the 128x64)
   Serial.begin(9600);
}

void loop() {

    display.clearDisplay();  //Clear Display
    drawPercentbar( 6, 2, 50, 10,p1);  //Draw Bar @ (Y=0, X=20, Length=100, p2=Start from which percentage"This test is start from random percentage, see line 11)
    drawPercentbar( 0, 20, 100, 15, p2);  //Draw Bar @ (Y=0, X=20, Length=100, p2=Start from which percentage"This test is start from random percentage, see line 12)
    drawPercentbar( 0, 40, 128, 20,p3);  //Draw Bar @ (Y=0, X=20, Length=100, p2=Start from which percentage"This test is start from random percentage, see line 13)
    display.display();

    p1++;p2++;p3++;
    if( p1 > 100) p1 =0;
    if( p2 > 100) p2 =0;
    if( p3 > 100) p3 =0;
    delay(100);  //Control the speen of the percent bar
}

void drawPercentbar(int x,int y, int width,int height, int progress) {
  
  //Here start made a persent bar
   progress = progress > 100 ? 100 : progress;
   progress = progress < 0 ? 0 : progress;
   float bar = ((float)(width-4) / 100) * progress;  //(wide-4 / 100) = Define the end of the bar at befor the frame
   display.drawRect(x, y, width, height, WHITE);  //Draw a rectangle
   display.fillRect(x+2, y+2, bar , height-4, WHITE);  //

  //Here start made the persentage text
  if( height >= 10){
    display.setCursor((width/2) -6, y+4);  //Text start @ ((X=width/2)-6,Y=Y+4)
    display.setTextSize(1);
    display.setTextColor(WHITE);

   //When the percentage = "50%" then will invert the text color
   if( progress >=50)  
     display.setTextColor(BLACK,WHITE); //(BLACK=Change text color to BLACK, WHITE=Change to WHITE color behine the text)
     display.print(progress);
     display.print("%");
  }
}