public class NachhilfeVerwaltung {
	private BinarySearchTree<Subject> management;
	private BinarySearchTree<Student> studentmanager;

	public NachhilfeVerwaltung() {
		studentmanager = new BinarySearchTree<Student>();
		management = new BinarySearchTree<Subject>();
		addSubject(new Subject("Mathe"));
		addSubject(new Subject("Informatik"));
		addSubject(new Subject("Deutsch"));
		addSubject(new Subject("Englisch"));
		addSubject(new Subject("Religion"));
		addSubject(new Subject("Sport"));
	}

	public void addSubject(Subject pSubject) {
		if(pSubject != null && management.search(pSubject) == null) {
			management.insert(pSubject);
			System.out.println("Subject: " + pSubject.getName() + " has been added");
		}
	}

	public Subject searchSubject(Subject pSubject) {
		if(pSubject != null) {
			return management.search(pSubject);
		} else {
			return null;
		}
	}

	public void removeSubject(Subject pSubject) {
		management.remove(pSubject);
		System.out.println("Subject: " + pSubject.getName() + " has been removed!");
	}

	public List<Subject> getAllSubjects() {
		if(!management.isEmpty()) {
			List<Subject> tmp = new List<Subject>();
			tmp = inOrderSubject(management,tmp);

			tmp.toFirst();
			while(tmp.hasAccess()) {
				System.out.println("Subject: " + tmp.getContent().getName());
				tmp.next();
			}

			return tmp;
		} else {
			System.out.println("ALARM");
			return null;
		}
	}

	public int numberOfSubjects() {
		List<Subject> tmp = new List<Subject>();
		tmp = inOrderSubject(management,tmp);
		tmp.toFirst();
		int i = 0;
		while(tmp.hasAccess()) {
			i++;
			tmp.next();
		}
		return i;
	}

	public void addStudent(Student pStudent) {
		if(pStudent != null && studentmanager.search(pStudent) == null) {
			studentmanager.insert(pStudent);
			System.out.println("Student: " + pStudent.getSurname() + " " + pStudent.getForename() + " has been added");
		}
	}

	public Student searchStudent(Student pStudent) {
		if(pStudent != null) {
			return studentmanager.search(pStudent);
		} else {
			return null;
		}
	}

	public void removeStudent(Student pStudent) {
		studentmanager.remove(pStudent);
		System.out.println("Subject: " + pStudent.getSurname() + " " + pStudent.getForename() + " has been removed!");
	}


	public List<Student> getAllStudents() {
		if(!studentmanager.isEmpty()) {
			List<Student> tmp = new List<Student>();
			tmp = inOrderStudent(studentmanager,tmp);

			tmp.toFirst();
			while(tmp.hasAccess()) {
				System.out.println("Subject: " + tmp.getContent().getSurname() + " " + tmp.getContent().getForename()
						+  " "); //+ tmp.getContent().getNumberOfSubjects()[].getName());
				tmp.next();
			}

			return tmp;
		} else {
			System.out.println("ALARM");
			return null;
		}
	}

	private List<Student> inOrderStudent(BinarySearchTree<Student> pCurrentTree, List<Student> pList) {
		List<Student> sorted = pList;
		if(!pCurrentTree.isEmpty()) {
			if(!pCurrentTree.getLeftTree().isEmpty()) {
			inOrderStudent(pCurrentTree.getLeftTree(), sorted);
			}
			sorted.append(pCurrentTree.getContent());
			if(!pCurrentTree.getRightTree().isEmpty()) {
			inOrderStudent(pCurrentTree.getRightTree(), sorted);
			}
		}
		return sorted;
	}

	private List<Subject> inOrderSubject(BinarySearchTree<Subject> pCurrentTree, List<Subject> pList) {
		List<Subject> sorted = pList;
		if(!pCurrentTree.isEmpty()) {
			if(!pCurrentTree.getLeftTree().isEmpty()) {
			inOrderSubject(pCurrentTree.getLeftTree(), sorted);
			}
			sorted.append(pCurrentTree.getContent());
			if(!pCurrentTree.getRightTree().isEmpty()) {
			inOrderSubject(pCurrentTree.getRightTree(), sorted);
			}
		}
		return sorted;
	}

}