#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include "DHT.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);

#define REED_SWITCH_PIN 2 // Pin where the reed switch is connected
#define DHTPIN 3          // Pin where the DHT22 sensor is connected
#define BUTTON_PIN 4      // Pin where the momentary button is connected
#define DHTTYPE DHT22     // DHT 22 (AM2302)
#define LED_PIN 13        // Onboard LED pin
#define LED_PIN2 9        // LED pin
bool ledState;

DHT dht(DHTPIN, DHTTYPE);

unsigned long previousMillis = 0;  // Stores last time the garage state was checked
unsigned long previousMillisforLED = 0;   //interval checking for flashing the LED
const long interval = 10;        // Interval to check garage state (5 seconds)

void setup() {
  Serial.begin(9600);
  dht.begin();
  
  // Initialize reed switch pin as input
  pinMode(REED_SWITCH_PIN, INPUT_PULLUP);

  // Initialize button pin as input with internal pull-up
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(LED_PIN2, OUTPUT);  // Set LED pin as output

  // Initialize SSD1306 display
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Pass 0x3C as the I2C address
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Halt if display initialization fails
  }

  // Initial display setup
  display.clearDisplay();
  display.setTextSize(1);  
  display.setTextColor(SSD1306_WHITE);
  display.setFont(NULL); 
  display.display();
}

void loop() {
  unsigned long currentMillis = millis(); // Get the current time
  unsigned long currentMillisforLED = millis();

  // Check garage state every 5 seconds
  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;  // Save the last time the garage state was checked
    
    // Read the state of the reed switch (garage open/shut)
    bool reedState = digitalRead(REED_SWITCH_PIN);

    // Garage door is open (reed switch HIGH)
    if (reedState == LOW) {
      display.clearDisplay();
      display.setTextSize(2);  // Increase text size for "Garage open"
      display.setCursor(0, 10);
      display.println("  Garage");
      display.println("   open");
      display.display();
      // Serial.println("Garage open");
      // Flash the external LED (2 seconds on, 2 seconds off)
      if (currentMillisforLED - previousMillisforLED >= 2000) {
        previousMillisforLED = currentMillisforLED;  // Save the last time the LED flashed
        if (ledState == false){
          digitalWrite(LED_PIN2, LOW);
          ledState = true;
        }
        else{
          digitalWrite(LED_PIN2,HIGH);
          ledState = false;
        }
      }
    }
    // Garage door is shut (reed switch LOW)
    else {
      display.clearDisplay(); // Blank the display when the garage is shut
      display.display();
      // Serial.println("Garage shut");
      digitalWrite(LED_PIN2, LOW);
      digitalWrite(LED_PIN, LOW);
    }
  }

  // Read the state of the button (active LOW)
  bool buttonState = digitalRead(BUTTON_PIN);
  
  
  // If the garage is shut and the button is pressed, show temperature and humidity
  bool reedState = digitalRead(REED_SWITCH_PIN); // Get reed state again
  
  if (reedState == HIGH && buttonState == LOW) {
    float h = dht.readHumidity();
    float t = dht.readTemperature();
    
    if (isnan(h) || isnan(t)) {
      Serial.println(F("Failed to read from DHT sensor!"));
      display.setCursor(0, 10);
      display.println("DHT read fail");
    } else {
      display.setTextSize(2);  // Set text size to normal for temperature and humidity
      display.setCursor(0, 10);
      display.print("T: ");
      display.print(t);
      display.println(" C");

      display.setCursor(0, 30);
      display.print("H: ");
      display.print(h);
      display.println(" %");

      // Serial.print("Temp: ");
      // Serial.print(t);
      // Serial.print(" C, Humidity: ");
      // Serial.println(h);
    }

    // Display the temperature and humidity for 10 seconds
    display.display();
    delay(6000);

    // After 10 seconds, blank the screen again
   display.display();
  }

  delay(100);  // Small delay to avoid bouncing or rapid updates
}