#include <Adafruit_SSD1306.h>
#include "DHTesp.h"
#include <WiFi.h>
#include <HTTPClient.h>

// OLED Display Settings
Adafruit_SSD1306 display(128, 64, &Wire, -1);

// Wi-Fi Settings
const char* ssid = "Wokwi-GUEST";          // Wi-Fi SSID
const char* password = "";                 // Wi-Fi password (empty for Wokwi)

// ThingSpeak Settings
const char* server = "http://api.thingspeak.com/update"; // ThingSpeak server
String apiKey = "6ELCHRTEBEDGUCQB";                      // Your ThingSpeak API Key

// Pin Definitions
const int soilPin = 34;   // Pin for potentiometer (simulates soil moisture sensor)
const int buzzerPin = 25; // Pin for buzzer
const int ledPin = 26;    // Pin for LED
const int DHT_PIN = 15;   // Pin for DHT22 data

// Variables for dynamic temperature and humidity
float simulatedTemperature = 25.0;
float simulatedHumidity = 50.0;

int soilValue = 0;

// Function to simulate dynamic temperature and humidity
void updateSimulatedValues() {
  // Change temperature and humidity dynamically
  simulatedTemperature += random(-10, 11) / 10.0; // Change by -1.0 to +1.0
  simulatedHumidity += random(-10, 11) / 10.0;    // Change by -1.0 to +1.0

  // Keep values within realistic limits
  if (simulatedTemperature < 15.0) simulatedTemperature = 15.0;
  if (simulatedTemperature > 35.0) simulatedTemperature = 35.0;

  if (simulatedHumidity < 20.0) simulatedHumidity = 20.0;
  if (simulatedHumidity > 80.0) simulatedHumidity = 80.0;
}

void setup() {
  Serial.begin(115200);

  // Pin Modes
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  digitalWrite(buzzerPin, LOW);
  digitalWrite(ledPin, LOW);

  // Initialize OLED Display
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("OLED display failed to initialize!");
    while (1);
  }
  display.clearDisplay();

  // Wi-Fi Connection
  Serial.println("Connecting to Wi-Fi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWi-Fi connected!");
}

void sendDataToThingSpeak(int soilValue, float temperature, float humidity) {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    // Create the URL string
    String url = String(server) + "?api_key=" + apiKey +
                 "&field1=" + String(soilValue) +
                 "&field2=" + String(temperature) +
                 "&field3=" + String(humidity);

    // Send HTTP GET request
    http.begin(url);
    int httpResponseCode = http.GET();

    if (httpResponseCode > 0) {
      Serial.println("Data sent to ThingSpeak! Response code: " + String(httpResponseCode));
    } else {
      Serial.println("Error sending data to ThingSpeak. Response code: " + String(httpResponseCode));
    }
    http.end();
  } else {
    Serial.println("Wi-Fi not connected. Data not sent.");
  }
}

void loop() {
  // Update simulated temperature and humidity
  updateSimulatedValues();

  // Read soil moisture
  soilValue = analogRead(soilPin);

  // Display data on OLED
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("Soil Moisture: " + String(soilValue));
  display.println("Temperature: " + String(simulatedTemperature) + " C");
  display.println("Humidity: " + String(simulatedHumidity) + " %");
  display.display();

  // Send data to ThingSpeak
  sendDataToThingSpeak(soilValue, simulatedTemperature, simulatedHumidity);

  // LED and Buzzer Control
  if (soilValue < 1500) {  // Critical threshold value
    digitalWrite(ledPin, HIGH);    // Turn ON LED
    digitalWrite(buzzerPin, HIGH); // Activate Buzzer
    Serial.println("Soil is dry! Irrigation started.");
  } else {
    digitalWrite(ledPin, LOW);     // Turn OFF LED
    digitalWrite(buzzerPin, LOW);  // Deactivate Buzzer
    Serial.println("Soil is moist. No irrigation needed.");
  }

  delay(20000); // Wait for 20 seconds before next iteration
}