/*
  SSD1306 Fuel Gauge

  This example code is in the public domain.
*/

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

int level = 0;
int x = 0;

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// these constants won't change:
const int ambient = A0;   // the pin that the potentiometer is attached to
const int fuelGross = A1;   // the pin that the potentiometer is attached to
const int barCount = 4;    // the number of barss in the bar graph

int blocks[] = {
  1, 2, 3, 4, 5,
};   // an array of blocks


void setup() {
  Serial.begin(115200);

  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }
  delay(1000); // Pause for 1 seconds

  // Clear the buffer
  display.clearDisplay();

  // Draw petrol pump
  display.fillRect(1, 6, 30, 16, WHITE);
  display.fillRect(20, 9, 8, 10, BLACK);
  display.drawLine(0, 4, 0, 24, WHITE);
  display.drawLine(22, 22, 22, 24, WHITE);
  display.drawLine(22, 24, 8, 24, WHITE);
  display.drawLine(8, 24, 8, 26, WHITE);
  display.drawLine(8, 26, 8, 28, WHITE);
  display.drawLine(8, 28, 22, 28, WHITE);
  display.drawLine(22, 28, 28, 26, WHITE);
  display.display();
}

void drawBlock0() {
  display.fillRect(33, 0, 15, 64, WHITE);
  //  display.drawLine(level, 0, level, 64, WHITE);
  display.display();
  delay(2000);
  display.fillRect(33, 0, 15, 64, BLACK);
  display.display();
}
void drawBlock1() {
  display.fillRect(33, 0, 15, 64, WHITE);
  //  display.drawLine(level, 0, level, 64, WHITE);
  display.display();
}
void drawBlock2() {
  display.fillRect(53, 0, 15, 64, WHITE);
  display.display();
}
void drawBlock3() {
  display.fillRect(73, 0, 15, 64, WHITE);
  display.display();
}
void drawBlock4() {
  display.fillRect(93, 0, 15, 64, WHITE);
  display.display();
}
void undrawBlock2() {
  display.fillRect(53, 0, 15, 64, BLACK);
  display.display();
}
void undrawBlock3() {
  display.fillRect(73, 0, 15, 64, BLACK);
  display.display();
}
void undrawBlock4() {
  display.fillRect(93, 0, 15, 64, BLACK);
  display.display();
}

void loop() {
  // read the ambient pressure:
  int sensorReading = analogRead(ambient);
  // read the Fuel pressure:
  int sensorReading2 = analogRead(fuelGross);

 int fuelNet = sensorReading2 - sensorReading;


  // map the result to a range from 0 to the number of blocks:
  int barLevel = map(fuelNet, 0, 1023, 0, 5);

  // loop over the array:
  for (int blocks = 0; blocks < 5; blocks++) {
    Serial.println(barLevel);

    switch (barLevel) {
      case 0:
        drawBlock0();
        undrawBlock2();
        undrawBlock3();
        undrawBlock4();
        break;

      case 1:  //
        drawBlock1();
        undrawBlock2();
        undrawBlock3();
        undrawBlock4();
        break;

      case 2:  // y
        drawBlock1();
        drawBlock2();
        undrawBlock3();
        undrawBlock4();
        break;

      case 3:  //
        drawBlock1();
        drawBlock2();
        drawBlock3();
        undrawBlock4();
        break;

      case 4:
        drawBlock1();
        drawBlock2();
        drawBlock3();
        drawBlock4();
        break;
    } 
  }
   delay(1000); // Pause for 1 seconds
}