#include <U8glib.h>

U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NONE | U8G_I2C_OPT_DEV_0);

int xmax = 128;
int ymax = 64;
int xcenter = xmax / 2;
int ycenter = ymax / 2 + 10;
int arc = ymax / 2;
int angle = 0;
char* label[] = {"Km/h", "COOLANT", "INTAKE", "VOLT"};
int labelXpos[] = {53, 45, 49, 53};
#define irSensorPin 2 // Digital pin for IR sensor
#define minRotationSpeed 0 // Minimum rotation speed (adjust as needed)

int p, w, m, a = 10;
u8g_uint_t xx = 0;

void gauge(uint8_t angle) {
  u8g.drawCircle(xcenter, ycenter, arc + 3, U8G_DRAW_UPPER_RIGHT);
  u8g.drawCircle(xcenter, ycenter, arc + 1, U8G_DRAW_UPPER_RIGHT);
  u8g.drawCircle(xcenter, ycenter, arc + 3, U8G_DRAW_UPPER_LEFT);
  u8g.drawCircle(xcenter, ycenter, arc + 1, U8G_DRAW_UPPER_LEFT);

  float x1 = sin(2 * angle * 2 * 3.14 / 360);
  float y1 = cos(2 * angle * 2 * 3.14 / 360);
  u8g.drawLine(xcenter, ycenter, xcenter + arc * x1, ycenter - arc * y1);
  u8g.drawDisc(xcenter, ycenter, 5, U8G_DRAW_UPPER_LEFT);
  u8g.drawDisc(xcenter, ycenter, 5, U8G_DRAW_UPPER_RIGHT);
  u8g.setFont(u8g_font_chikita);

  u8g.drawStr(24, 42, "0");
  u8g.drawStr(25, 30, "10");
  u8g.drawStr(27, 20, "20");
  u8g.drawStr(36, 12, "30");
  u8g.drawStr(47, 7, "40");
  u8g.drawStr(60, 5, "50");
  u8g.drawStr(73, 7, "60");
  u8g.drawStr(84, 12, "70");
  u8g.drawStr(92, 20, "80");
  u8g.drawStr(98, 30, "90");
  u8g.drawStr(100, 42, "100");

  u8g.setPrintPos(labelXpos[0], 32);
  u8g.print(label[0]);

  u8g.setFont(u8g_font_profont22);
  u8g.setPrintPos(54, 60);
  if (w < 0) {
    u8g.print("0");
  }
  if (w > 99) {
    u8g.setPrintPos(47, 60);
  }
  u8g.print(w);
}

void drawBatteryIndicator(int batteryLevel) {
  int barWidth = 2;  // Width of each bar in pixels
  int numBars = 4;   // Number of bars in the battery indicator
  int spacing = 1;   // Spacing between bars
  int startY = 58;   // Y position for battery indicator

  int totalWidth = (barWidth * numBars) + ((numBars - 1) * spacing);  // Total width of the indicator

  // Calculate the starting X position to center the indicator
  int startX = (xmax - totalWidth) / 2;

  // Calculate the height of the indicator
  int indicatorHeight = 5;

  // Draw the frame of the indicator
  u8g.drawFrame(startX, startY, totalWidth, indicatorHeight);

  // Calculate the width of each bar segment
  int segmentWidth = barWidth + spacing;

  // Draw the filled bars based on the battery level
  for (int i = 0; i < numBars; i++) {
    int barX = startX + (i * segmentWidth);
    int barY = startY + 1;
    if (i * 100 / numBars <= batteryLevel) {
      // Draw a filled bar segment
      u8g.drawBox(barX, barY, barWidth, indicatorHeight - 2);
    } else {
      // Draw an empty bar segment
      u8g.drawFrame(barX, barY, barWidth, indicatorHeight - 2);
    }
  }
}



void setup(void) {
  pinMode(irSensorPin, INPUT); // Set IR sensor pin as input
  u8g.setFont(u8g_font_chikita);
  u8g.setColorIndex(1);

  if (u8g.getMode() == U8G_MODE_R3G3B2) {
    u8g.setColorIndex(255);
  } else if (u8g.getMode() == U8G_MODE_GRAY2BIT) {
    u8g.setColorIndex(3);
  } else if (u8g.getMode() == U8G_MODE_BW) {
    u8g.setColorIndex(1);
  } else if (u8g.getMode() == U8G_MODE_HICOLOR) {
    u8g.setHiColorByRGB(255, 255, 255);
  }
}

void loop(void) {
  // Read the state of the IR sensor
  int irSensorValue = digitalRead(irSensorPin);

  // Calculate the rotation speed based on IR sensor input
  if (irSensorValue == LOW) {
    // Object detected, increment rotation speed
    w++;
  } else {
    // No object detected, decrement rotation speed
    w--;
  }

  // Ensure rotation speed stays within defined limits
  w = constrain(w, minRotationSpeed, 100);

  // Calculate the angle for gauge display
  m = map(w, 0, 100, 0, 90);
  xx = m;
  if (xx < 45) {
    xx = xx + 135;
  } else {
    xx = xx - 45;
  }

  // Display the gauge and battery indicator
  u8g.firstPage();
  do {
    gauge(xx);
    drawBatteryIndicator(w); // Draw the battery indicator
  } while (u8g.nextPage());
}