import java.util.ArrayList;

import java.util.List;

import java.util.Scanner;

class MedicalHistory {

private String history;

public MedicalHistory(String history) {

this.history = history;

}

public String getHistory() {

return history;

}

}

class Patient {

private static int idCounter = 100;

private int patientId;

private String name;

private int age;

private MedicalHistory medicalHistory;

public Patient(String name, int age, String history) {

this.patientId = ++idCounter;

this.name = name;

this.age = age;

this.medicalHistory = new MedicalHistory(history);

}

public int getPatientId() {

return patientId;

}

public String getName() {

return name;

}

public int getAge() {

return age;

}

public MedicalHistory getMedicalHistory() {

return medicalHistory;

}

public void displayPatientInfo() {

System.out.println("Patient ID: " + patientId + ", Name: " + name + ", Age: " + age + ", Medical History: " + medicalHistory.getHistory());

}

}

class Doctor {

private static int idCounter = 500;

private int doctorId;

private String name;

private String specialty;

private List<Appointment> appointments = new ArrayList<>();

public Doctor(String name, String specialty) {

this.doctorId = ++idCounter;

this.name = name;

this.specialty = specialty;

}

public int getDoctorId() {

return doctorId;

}

public String getName() {

return name;

}

public String getSpecialty() {

return specialty;

}

public void addAppointment(Appointment appointment) {

appointments.add(appointment);

}

public void displayDoctorInfo() {

System.out.println("Doctor ID: " + doctorId + ", Name: " + name + ", Specialty: " + specialty);

System.out.println("Appointments:");

for (Appointment appointment : appointments) {

appointment.displayAppointment();

}

}

}

class Appointment {

private String date;

private String time;

private Patient patient;

private Doctor doctor;

public Appointment(String date, Patient patient, Doctor doctor) {

this.date = date;

this.patient = patient;

this.doctor = doctor;

doctor.addAppointment(this);

}

public Appointment(String date, String time, Patient patient, Doctor doctor) {

this(date, patient, doctor);

this.time = time;

}

public void displayAppointment() {

System.out.println("Appointment Date: " + date + (time != null ? " at " + time : "") + ", Patient: " + patient.getName() + ", Doctor: " + doctor.getName());

}

}

public class HospitalManagementSystem {

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

List<Patient> patients = new ArrayList<>();

List<Doctor> doctors = new ArrayList<>();

try {

while (true) {

System.out.println("\n1. Register Patient\n2. Register Doctor\n3. Schedule Appointment\n4. Display Doctor Info\n5. Display Patient Info\n6. Exit");

System.out.print("Choose an option: ");

int choice = Integer.parseInt(scanner.nextLine());

if (choice == 1) {

System.out.print("Enter Patient Name: ");

String name = scanner.nextLine();

System.out.print("Enter Age: ");

int age = Integer.parseInt(scanner.nextLine());

System.out.print("Enter Medical History: ");

String history = scanner.nextLine();

Patient patient = new Patient(name, age, history);

patients.add(patient);

System.out.println("Patient Registered with ID: " + patient.getPatientId());

} else if (choice == 2) {

System.out.print("Enter Doctor Name: ");

String name = scanner.nextLine();

System.out.print("Enter Specialty: ");

String specialty = scanner.nextLine();

Doctor doctor = new Doctor(name, specialty);

doctors.add(doctor);

System.out.println("Doctor Registered with ID: " + doctor.getDoctorId());

} else if (choice == 3) {

System.out.print("Enter Patient ID: ");

int patientId = Integer.parseInt(scanner.nextLine());

System.out.print("Enter Doctor ID: ");

int doctorId = Integer.parseInt(scanner.nextLine());

System.out.print("Enter Appointment Date (dd-mm-yyyy): ");

String date = scanner.nextLine();

System.out.print("Enter Appointment Time (optional, hh:mm or press enter): ");

String time = scanner.nextLine();

Patient patient = findPatientById(patients, patientId);

Doctor doctor = findDoctorById(doctors, doctorId);

if (patient != null && doctor != null) {

Appointment appointment;

if (!time.isEmpty()) {

appointment = new Appointment(date, time, patient, doctor);

} else {

appointment = new Appointment(date, patient, doctor);

}

System.out.println("Appointment scheduled successfully.");

} else {

System.out.println("Invalid Patient or Doctor ID.");

}

} else if (choice == 4) {

System.out.print("Enter Doctor ID: ");

int doctorId = Integer.parseInt(scanner.nextLine());

Doctor doctor = findDoctorById(doctors, doctorId);

if (doctor != null) {

doctor.displayDoctorInfo();

} else {

System.out.println("Doctor not found.");

}

} else if (choice == 5) {

System.out.print("Enter Patient ID: ");

int patientId = Integer.parseInt(scanner.nextLine());

Patient patient = findPatientById(patients, patientId);

if (patient != null) {

patient.displayPatientInfo();

} else {

System.out.println("Patient not found.");

}

} else if (choice == 6) {

System.out.println("Exiting the system.");

break;

} else {

System.out.println("Invalid choice. Please try again.");

}

}

} catch (NumberFormatException e) {

System.out.println("Invalid input. Please enter correct data.");

} finally {

scanner.close();

}

}

private static Patient findPatientById(List<Patient> patients, int id) {

for (Patient patient : patients) {

if (patient.getPatientId() == id) {

return patient;

}

}

return null;

}

private static Doctor findDoctorById(List<Doctor> doctors, int id) {

for (Doctor doctor : doctors) {

if (doctor.getDoctorId() == id) {

return doctor;

}

}

return null;

}

}