#include <Wire.h> 
#include <LiquidCrystal_I2C.h>

// --- Configuration ---
// I2C Address (0x27 is common, check if yours is 0x3F if it doesn't work)
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Pin Definitions
const int SOIL_PIN = 34; // Soil Sensor Analog Output
const int LED_R = 25;    // RGB LED Red Pin
const int LED_G = 33;    // RGB LED Green Pin
const int LED_B = 32;    // RGB LED Blue Pin

// Moisture thresholds based on your calibration values
// Raw values are typically 0 (wettest) to 4095 (driest) on ESP32
const int WET_THRESHOLD_MAX = 2165; // Raw value below this is considered WET
const int DRY_THRESHOLD_MIN = 3135; // Raw value above this is considered DRY

// --- Setup ---

void setup() {
  // Initialize I2C communication (SDA=23, SCL=22 are standard ESP32 pins)
  Wire.begin(23, 22); 

  Serial.begin(9600);
  
  // Set LED pins as outputs
  pinMode(LED_R, OUTPUT);
  pinMode(LED_G, OUTPUT);
  pinMode(LED_B, OUTPUT);
  
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.print("Soil Monitor");
  lcd.setCursor(0, 1);
  lcd.print("Ready...");
  delay(1000);
}

// --- Main Loop ---

void loop() {
  // Read the raw analog value from the soil sensor
  int16_t rawValue = analogRead(SOIL_PIN);
  String msg;

  // --- Logic for State Determination and LED Control ---
  
  // DRY State (Raw Value >= 3135) - Set RED
  if (rawValue >= DRY_THRESHOLD_MIN) {
    msg = "DRY";
    analogWrite(LED_R, 255); // Red ON
    analogWrite(LED_G, 0);   
    analogWrite(LED_B, 0);   
  } 
  // WET State (Raw Value <= 2165) - Set BLUE
  else if (rawValue <= WET_THRESHOLD_MAX) {
    msg = "WET";
    analogWrite(LED_R, 0);   
    analogWrite(LED_G, 0);   
    analogWrite(LED_B, 255); // Blue ON
  } 
  // OK State (Ideal, between 2165 and 3135) - Set GREEN
  else {
    msg = "OK";
    analogWrite(LED_R, 0);   
    analogWrite(LED_G, 255); // Green ON
    analogWrite(LED_B, 0);   
  }

  // --- Display Status on LCD ---
  
  // Clear the display for fresh data
  lcd.clear();
  
  // Line 1: Show Raw ADC Value for easy calibration
  lcd.print("Value: ");
  lcd.print(rawValue);
  
  // Line 2: Show Moisture Status (DRY, WET, or OK)
  lcd.setCursor(0, 1);
  lcd.print("Soil: ");
  lcd.print(msg); // Prints "DRY", "WET", or "OK"

  // Debugging output to Serial Monitor
  Serial.print("Value: ");
  Serial.print(rawValue);
  Serial.print(" | Status: ");
  Serial.println(msg);

  delay(1000); // Wait for 1 second before the next reading
}