#define BLYNK_TEMPLATE_ID "TMPL3DVdOd7NX"
#define BLYNK_TEMPLATE_NAME "Smart soil nutrition monitoring system"
#define BLYNK_AUTH_TOKEN "yPM0UWhoOYudSWwcQUgW74ip_Q9z7oer"

#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>
#include "DHTesp.h"
#include <HardwareSerial.h>

char ssid[] = "Galaxy 21";
char pass[] = "varshini";

const int DHT_PIN = 15;
DHTesp dhtSensor;

// Potentiometer is connected to GPIO 34 (Analog ADC1_CH6) 
const int potPin = 34;

// Buzzer pin
const int buzzerPin = 2;

// variable for storing the potentiometer value
int potValue = 0;

#define ncom 3 //  number of commands.
char commar[ncom] = {0x1, 0x3, 0x5}; // Actual commands
// Response Strings can be stored like this
char respar[ncom][30] = {"Nitrogen value is: ", "Phosphorous value is: ", "Potassium value is: "};
uint8_t rtValue[ncom]; // Store the return values from the custom chip

BlynkTimer timer;

void setup() {
  Serial.begin(115200);
  Serial2.begin(15200, SERIAL_8N1, 16, 17); // Custom chip communication line

  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);  

  timer.setInterval(2000L, sendData); // Send data every 2 seconds

  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  pinMode(buzzerPin, OUTPUT); // Initialize buzzer pin as output

  Serial.println("Hello, ESP32!");
}

void sendData() {
  float t = dhtSensor.getTemperature();
  float h = dhtSensor.getHumidity();
  
  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print("%\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.println(" °C");

  potValue = analogRead(potPin);
  Serial.println("Moisture: " + String(potValue));

  for (uint8_t i = 0; i < ncom; i++) {
    Serial2.print((char)commar[i]); // Send command through Serial2
    if (Serial2.available()) {
      rtValue[i] = Serial2.read(); // Read response from Serial2
      Serial2.flush(); // Clear Serial2 buffer
      Serial.print(respar[i]); // Print response
      Serial.println(rtValue[i]);
    }
  }

  // Send data to Blynk with correct virtual pins
  Blynk.virtualWrite(V0, potValue);       // Soil moisture
  Blynk.virtualWrite(V1, rtValue[0]);     // Nitrogen
  Blynk.virtualWrite(V2, rtValue[1]);     // Phosphorous
  Blynk.virtualWrite(V3, rtValue[2]);     // Potassium
  Blynk.virtualWrite(V4, t);              // Temperature
  Blynk.virtualWrite(V5, h);              // Humidity

  // Control the buzzer based on the moisture level
  if (potValue < 300) {
    digitalWrite(buzzerPin, HIGH); // Turn on buzzer
  } else {
    digitalWrite(buzzerPin, LOW); // Turn off buzzer
  }
}

void loop() {
  Blynk.run();
  timer.run();
}