#include <WiFi.h>           // WiFi library for ESP32
// #include <ESP8266WiFi.h>    // WiFi library for ESP32
#include "ThingSpeak.h"     // ThingSpeak library for sending data to the cloud

// Define pins
#define PIR_SENSOR_PIN 7     // Digital input pin for the PIR motion sensor
#define LDR_SENSOR_PIN 34    // Analog input pin for the LDR (photoresistor)

// WiFi credentials (Wokwi guest network has no password)
const char* ssid = "Wokwi-GUEST";     
const char* password = "";           

// Create a WiFiClient object for ThingSpeak communication
WiFiClient client;

// ThingSpeak configuration
unsigned long channelID = 2930049;                 // ThingSpeak Channel ID
const char* writeAPIKey = "3SQBNN8AL2DX2MUD";      // ThingSpeak Write API Key

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(115200);

  // Configure the PIR sensor pin as input
  pinMode(PIR_SENSOR_PIN, INPUT);

  // Connect to WiFi
  Serial.print("Connecting to WiFi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print("."); // Print dots while waiting
  }
  Serial.println("\nWiFi connected");

  // Initialize ThingSpeak with the WiFi client
  ThingSpeak.begin(client);
}

void loop() {
  // Read motion detection value from PIR sensor (0 = no motion, 1 = motion)
  int pirValue = digitalRead(PIR_SENSOR_PIN);

  // Read analog value from LDR (light intensity)
  int rawLdrValue = analogRead(LDR_SENSOR_PIN);

  // Constrain the LDR value to a practical range to avoid outliers
  rawLdrValue = constrain(rawLdrValue, 32, 4063);

  // Map the LDR analog value (from 32 to 4063) to a luminosity scale (0 to 100000)
  // Higher raw value = darker environment → lower luminosity
  float luminosity = (4063 - rawLdrValue) * (100000.0 / (4063 - 32));

  // Print sensor data to the Serial Monitor for debugging and validation
  Serial.print("PIR Value: ");
  Serial.print(pirValue);
  Serial.print(" | Raw LDR: ");
  Serial.print(rawLdrValue);
  Serial.print(" | Mapped Luminosity: ");
  Serial.println((int)luminosity);

  // Prepare data fields for ThingSpeak
  ThingSpeak.setField(1, pirValue);            // Field 1: PIR motion status
  ThingSpeak.setField(2, (int)luminosity);     // Field 2: Mapped luminosity value

  // Send data to ThingSpeak channel
  int x = ThingSpeak.writeFields(channelID, writeAPIKey);

  // Check if data was sent successfully
  if (x == 200) {
    Serial.println("Data sent to ThingSpeak successfully.");
  } else {
    Serial.print("Error sending data: ");
    Serial.println(x); // Error code helps with debugging
  }

  // Wait 15 seconds before next upload
  delay(15000);
}