package map;

import position.NodePositionList;
import position.Position;
import position.PositionList;
import priorityqueue.Entry;
import priorityqueue.MyEntry;

import exceptions.InvalidKeyException;
import java.util.Iterator;

/**
 * Created with MONSTER.
 * User: xgiovio
 * Date: 11/05/2014
 * Time: 18:01
 */
public class ListMap<K,V> implements Map<K,V> {

    private PositionList<Entry<K,V>> L;

    public ListMap(){
        L =new NodePositionList<Entry<K,V>>();
    }

    @Override
    public int size() {
        return L.size();
    }

    @Override
    public boolean isEmpty() {
        return (L.isEmpty());
    }




    public V put(K key, V value) throws InvalidKeyException {
        checkKey(key);
        for(Position<Entry<K,V>> p: L.positions()){
            Entry<K,V> e= p.element();
            if(e.getKey().equals(key)){
                V v = e.getValue();
                L.set(p, new MyEntry<K,V>(key,value));
                return v;
            } }
        L.addLast(new MyEntry<K,V>(key,value));
        return null;
    }

    public V get(K key) throws InvalidKeyException{
        checkKey(key);
        for(Position<Entry<K,V>> p: L.positions()){
            Entry<K,V> e= p.element();
            if(e.getKey().equals(key)) return e.getValue();
        }
        return null;
    }


    public V remove(K key) throws InvalidKeyException {
        checkKey(key);
        for(Position<Entry<K,V>> p: L.positions()){
            Entry<K,V> e= p.element();
            if(e.getKey().equals(key)){
                V v = e.getValue();
                L.remove(p);
                return v;
            }
        }
        return null;
    }

    @Override
    public Iterable<K> keys() {
        Iterator<Entry<K,V>> it = L.iterator();
        NodePositionList<K> ret = new NodePositionList<K>();
        for (;it.hasNext();){
            ret.addLast(it.next().getKey());
        }
        return ret;
    }

    @Override
    public Iterable<V> values() {
        Iterator<Entry<K,V>> it = L.iterator();
        NodePositionList<V> ret = new NodePositionList<V>();
        for (;it.hasNext();){
            ret.addLast(it.next().getValue());
        }
        return ret;
    }

    @Override
    public Iterable<Entry<K, V>> entries() {
        return L;
    }



    // auxiliar
    protected void checkKey(K key) throws InvalidKeyException {
              if (key == null )
                throw new InvalidKeyException("Invalid key");
    }


    @Override
    public String toString() {
        return L.toString();
    }
}