#include <WiFi.h>
#include <HTTPClient.h>
#include <SD.h>
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_SSD1306.h>

const char* ssid = "Wokwi-GUEST"; 
const char* password = ""; 

const String apiKey = "32AH0NSPZHF20RYI"; // ThingSpeak API key
const int chipSelect = 5; // SD card chip select pin

int motion = 0;  // Motion state (0 = no motion, 1 = motion detected)
int door = 1;    // Door state (0 = closed, 1 = open)

#define SCREEN_WIDTH 128  // Screen width
#define SCREEN_HEIGHT 64  // Screen height
#define OLED_RESET    -1  // No reset pin
#define SSD1306_I2C_ADDRESS 0x3C  // I2C address of the OLED screen

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET); // OLED display object

void setup() {
  Serial.begin(115200); // Start serial communication

  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.print(".");
  }
  Serial.println("\nConnected to Wi-Fi!");
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP()); // Print the IP address

  // Initialize OLED screen
  if (!display.begin(SSD1306_SWITCHCAPVCC, SSD1306_I2C_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;); // Stop execution if screen fails to initialize
  }
  display.clearDisplay();
  display.setTextSize(1);      // Set text size
  display.setTextColor(SSD1306_WHITE);  // Set text color to white
  display.setCursor(0, 0);     // Set cursor to top-left corner
  display.println(F("Starting..."));
  display.display();
  
  // Initialize SD card
  if (!SD.begin(chipSelect)) {
    Serial.println("SD card initialization failed!");
    while (1); // Stop execution if SD card initialization fails
  }
  Serial.println("SD card initialized");

  // Create or open log file
  File dataFile = SD.open("/log.csv", FILE_WRITE);
  if (dataFile) {
    dataFile.println("Motion,Door"); // Write header if file is new
    dataFile.close();
    Serial.println("log.csv file is ready.");
  } else {
    Serial.println("Error: Could not create log.csv file.");
  }
}

void loop() {
  // Write data to log.csv
  File dataFile = SD.open("/log.csv", FILE_APPEND);
  if (dataFile) {
    String data = String(motion) + "," + String(door);
    dataFile.println(data); // Write data to the file
    dataFile.close(); // Close the file
    Serial.println("Data written to log.csv: Motion: " + String(motion) + ", Door: " + String(door));
  } else {
    Serial.println("Error: Could not open log.csv file for writing.");
  }

  // Send data to ThingSpeak
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = "http://api.thingspeak.com/update?api_key=" + apiKey +
                 "&field1=" + String(motion) + "&field2=" + String(door);
    http.begin(url);
    int httpResponseCode = http.GET();
    
    if (httpResponseCode > 0) {
      String response = http.getString(); // Get the response from ThingSpeak
      Serial.println("Response: " + response);
    }
    http.end(); // End HTTP connection
  }

  // Update OLED screen with motion and door status
  display.clearDisplay();
  display.setCursor(0, 0);

  // Display motion status
  if (motion == 0) {
    display.println("No motion detected");
  } else {
    display.println("Motion detected");
  }

  // Display door status
  if (door == 0) {
    display.println("Door is closed");
  } else {
    display.println("Door is open");
  }

  display.display();  // Update the display

  // Simulate changing motion and door states (remove these when using actual sensors)
  motion = (motion + 1) % 2;  // Toggle motion state
  door = (door + 1) % 2;      // Toggle door state

  delay(15000);  // Wait for 15 seconds before repeating
}