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

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

#define OLED_RESET    -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

const int pirPin = 13;  // PIR sensor output pin
volatile unsigned long lastPirTime = 0;
volatile unsigned long pirInterval = 1000; // Set the PIR interval in milliseconds
volatile int pirCount = 0;

void IRAM_ATTR handlePirInterrupt() {
  if (millis() - lastPirTime > pirInterval) {
    pirCount++;
    lastPirTime = millis();
  }
}

void setup() {
  Serial.begin(9600);

  // Initialize PIR sensor pin
  pinMode(pirPin, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(pirPin), handlePirInterrupt, FALLING);

  // Initialize OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3C for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  // Clear the buffer
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);

  // Set text size and display message
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.println("Speed Detector");
  display.display();
  delay(2000);
}

void loop() {
  // Clear the buffer
  display.clearDisplay();

  // Display PIR count
  display.setTextSize(2);
  display.setCursor(0, 0);
  display.print("Count: ");
  display.println(pirCount);

  // Calculate speed (count per second)
  float speed = pirCount / 2.0; // Assuming interval of 0.5 seconds
  display.setTextSize(2);
  display.setCursor(0, 20);
  display.print("Speed: ");
  display.println(speed, 1);
  
  // Reset PIR count if necessary
  if (millis() - lastPirTime > 500) {
    pirCount = 0;
  }

  // Display on OLED
  display.display();
  delay(100);
}