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

// ================= UNDERGROUND CABLE FAULT =================
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Relay pins
const int line1RelayPin = 18;
const int line2RelayPin = 4;

// Fault check points
const int r1Pin = 12;
const int r2Pin = 26;
const int g1Pin = 25;
const int g2Pin = 14;
const int v1Pin = 33;
const int v2Pin = 27;

// Latitude and Longitude (example values)
float latR1 = 19.031124, lonR1 = 72.841415;
float latR2 = 19.031924, lonR2 = 72.859415;
float latG1 = 19.021224, lonG1 = 72.842415;
float latG2 = 19.021924, lonG2 = 72.849415;
float latV1 = 19.111146, lonV1 = 72.861736;
float latV2 = 19.113646, lonV2 = 72.869736;

// Distance definitions
const int distanceR = 1;
const int distanceG = 2;
const int distanceV = 3;

// Variables
String lastLineNumber;
int lastDistance = 0;
float lastLat = 0.0, lastLon = 0.0;
int faultFlag = 0;

// Track what’s currently displayed
String currentScreen = "";

// Timing for LCD switching
unsigned long lastSwitchTime = 0;
bool showFirstScreen = true;

// ================= SETUP =================
void setup() {
  Serial.begin(115200);

  lcd.init();
  lcd.backlight();

  pinMode(line1RelayPin, OUTPUT);
  pinMode(line2RelayPin, OUTPUT);

  pinMode(r1Pin, INPUT_PULLUP);
  pinMode(r2Pin, INPUT_PULLUP);
  pinMode(g1Pin, INPUT_PULLUP);
  pinMode(g2Pin, INPUT_PULLUP);
  pinMode(v1Pin, INPUT_PULLUP);
  pinMode(v2Pin, INPUT_PULLUP);

  Serial.println("System Initialized");

  showHomeScreen();
  delay(1000);
}

// ================= LOOP =================
void loop() {
  int r1State = digitalRead(r1Pin);
  int g1State = digitalRead(g1Pin);
  int v1State = digitalRead(v1Pin);

  int r2State = digitalRead(r2Pin);
  int g2State = digitalRead(g2Pin);
  int v2State = digitalRead(v2Pin);

  faultFlag = 0;

  if (r1State == HIGH) {
    updateFault("1", distanceR, latR1, lonR1, line1RelayPin);
  } else if (g1State == HIGH) {
    updateFault("1", distanceG, latG1, lonG1, line1RelayPin);
  } else if (v1State == HIGH) {
    updateFault("1", distanceV, latV1, lonV1, line1RelayPin);
  }

  if (r2State == HIGH) {
    updateFault("2", distanceR, latR2, lonR2, line2RelayPin);
  } else if (g2State == HIGH) {
    updateFault("2", distanceG, latG2, lonG2, line2RelayPin);
  } else if (v2State == HIGH) {
    updateFault("2", distanceV, latV2, lonV2, line2RelayPin);
  }

  if (faultFlag == 1) {
    printLastFault();
  } else {
    digitalWrite(line1RelayPin, LOW);
    digitalWrite(line2RelayPin, LOW);
    showHomeScreen();
  }

  delay(500);
}

// ================= FUNCTIONS =================
void showHomeScreen() {
  String newScreen = "Underground Cable\nNo Fault Found";
  if (newScreen != currentScreen) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Underground Cable");
    lcd.setCursor(0, 1);
    lcd.print("No Fault Found");
    currentScreen = newScreen;
  }
}

void updateFault(const String& line, int distance, float lat, float lon, int relayPin) {
  lastLineNumber = line;
  lastDistance = distance;
  lastLat = lat;
  lastLon = lon;
  faultFlag = 1;
  digitalWrite(relayPin, HIGH);
}

void printLastFault() {
  // Switch screen every 2 seconds
  if (millis() - lastSwitchTime > 2000) {
    lastSwitchTime = millis();
    showFirstScreen = !showFirstScreen;
  }

  if (showFirstScreen) {
    // Show Line and Distance
    String newScreen = "Line " + lastLineNumber + " Dist:" + String(lastDistance) + "km";
    if (newScreen != currentScreen) {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Fault on Line ");
      lcd.print(lastLineNumber);
      lcd.setCursor(0, 1);
      lcd.print("Dist: ");
      lcd.print(lastDistance);
      lcd.print(" km");
      currentScreen = newScreen;
    }
  } else {
    // Show full Latitude and Longitude
    String newScreen = "Lat:" + String(lastLat, 6) + " Lon:" + String(lastLon, 6);
    if (newScreen != currentScreen) {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Lat:");
      lcd.print(lastLat, 6);
      lcd.setCursor(0, 1);
      lcd.print("Lon:");
      lcd.print(lastLon, 6);
      currentScreen = newScreen;
    }
  }

  // Serial monitor (always print complete info)
  Serial.println("===== LAST FAULT DETAILS =====");
  Serial.print("Line: "); Serial.println(lastLineNumber);
  Serial.print("Distance: "); Serial.print(lastDistance); Serial.println(" km");
  Serial.print("Latitude: "); Serial.print(lastLat, 6); 
  Serial.print(" | Longitude: "); Serial.println(lastLon, 6);
  Serial.println("================================");
}