package net.atoms.NobleGases;
	import javax.servlet.http.HttpSession; 
	import java.util.ArrayList;
	import java.util.Collection;
	import java.util.Iterator;
	import java.util.Random;

	public class AtomsMap {
	
	private Collection atoms;
	
	private void init(HttpSession session) {
	atoms = new ArrayList();
	Random random = new Random();
	atoms.add(new Atom(Math.abs(random.nextLong()), "Helium", "He",2,4.003, true));
	atoms.add(new Atom(Math.abs(random.nextLong()), "Neon", "Ne",10,20.180, true));
	atoms.add(new Atom(Math.abs(random.nextLong()), "Argon", "Ar",18,39.948, true));
	atoms.add(new Atom(Math.abs(random.nextLong()), "Krypton" ,"Kr",36,83.8, true));
	atoms.add(new Atom(Math.abs(random.nextLong()), "Xenon", "Xe",54,131.29, true));
	atoms.add(new Atom(Math.abs(random.nextLong()), "Radon", "Rn",86,222.0, true));
	atoms.add(new Atom(Math.abs(random.nextLong()), "Sodium", "Na",11,22.99,false));
	session.setAttribute("key", atoms);
	}
	

	private void loadData(HttpSession session) {
	atoms = (Collection) session.getAttribute("key");
	if (atoms == null)
	init(session);
	}

	
	private void saveData(HttpSession session) {
	session.setAttribute("key", atoms);
	}

	
	public long saveToDB(Atom atom, HttpSession session) {
	loadData(session);
	boolean atomExist = false;
	ArrayList atomsNew = (ArrayList) atoms;
	int index = 0;
	for (Iterator iter = atoms.iterator(); iter.hasNext();) {
	Atom element = (Atom) iter.next();
	if (element.getId() == atom.getId()) {
	atomsNew.set(index, atom);
	atomExist = true;
	break;
	}
	index++;
	}
	atoms = atomsNew;     
	if (atomExist == false) {
	Random random = new Random();
	atom.setId(random.nextLong());
	atoms.add(atom);
	}
	saveData(session);
	return atom.getId();
	}

	
	public Atom loadAtomById(long id, HttpSession session) {
	loadData(session);
	for (Iterator iter = atoms.iterator(); iter.hasNext();) {
	Atom element = (Atom) iter.next();
	if (element.getId() == id) return (Atom) element;
	}
	return null;
	}

	
	
	public void deleteAtomById(long id, HttpSession session){
	loadData(session);
	Collection atomsNew = new ArrayList();
	for (Iterator iter = atoms.iterator(); iter.hasNext();) {
	Atom element = (Atom) iter.next();
	if (element.getId() != id){
	atomsNew.add(element);
	}
	}
	atoms = atomsNew;       
	saveData(session);
	}
	
	public Collection getAllAtoms(HttpSession session) {
	loadData(session);
	return atoms;
	}
	}