/*
	This file is part of the OdinMS Maple Story Server
    Copyright (C) 2008 Patrick Huy <patrick.huy@frz.cc>
		       Matthias Butz <matze@odinms.de>
		       Jan Christian Meyer <vimes@odinms.de>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as
    published by the Free Software Foundation version 3 as published by
    the Free Software Foundation. You may not use, modify or distribute
    this program under any other version of the GNU Affero General Public
    License.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package tools;

import java.util.*;

public class ArrayMap<K, V> extends AbstractMap<K, V> {

    static class Entry<K, V> implements Map.Entry<K, V> {
        protected K key;
        protected V value;

        public Entry(K key, V value) {
            this.key = key;
            this.value = value;
        }

        @Override
        public K getKey() {
            return key;
        }

        @Override
        public V getValue() {
            return value;
        }

        @Override
        public V setValue(V newValue) {
            V oldValue = value;
            value = newValue;
            return oldValue;
        }

        @Override
        public boolean equals(Object o) {
            if (!(o instanceof Map.Entry<?, ?>)) {
                return false;
            }
            Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
            return (key == null ? e.getKey() == null : key.equals(e.getKey())) && (value == null ? e.getValue() == null : value.equals(e.getValue()));
        }

        @Override
        public int hashCode() {
            int keyHash = (key == null ? 0 : key.hashCode());
            int valueHash = (value == null ? 0 : value.hashCode());
            return keyHash ^ valueHash;
        }

        @Override
        public String toString() {
            return key + "=" + value;
        }
    }

    private Set<? extends java.util.Map.Entry<K, V>> entries = null;
    private final ArrayList<Entry<K, V>> list;

    public ArrayMap() {
        list = new ArrayList<>();
    }

    public ArrayMap(Map<K, V> map) {
        list = new ArrayList<>();
        putAll(map);
    }

    public ArrayMap(int initialCapacity) {
        list = new ArrayList<>(initialCapacity);
    }

    @Override
    @SuppressWarnings("unchecked")
    public Set<java.util.Map.Entry<K, V>> entrySet() {
        if (entries == null) {
            entries = new AbstractSet<Entry<K, V>>() {
                @Override
                public void clear() {
                    throw new UnsupportedOperationException();
                }

                @Override
                public Iterator<Entry<K, V>> iterator() {
                    return list.iterator();
                }

                @Override
                public int size() {
                    return list.size();
                }
            };
        }
        return (Set<java.util.Map.Entry<K, V>>) entries;
    }

    @Override
    public V put(K key, V value) {
        int size = list.size();
        Entry<K, V> entry = null;
        int i;
        if (key == null) {
            for (i = 0; i < size; i++) {
                entry = (list.get(i));
                if (entry.getKey() == null) {
                    break;
                }
            }
        } else {
            for (i = 0; i < size; i++) {
                entry = (list.get(i));
                if (key.equals(entry.getKey())) {
                    break;
                }
            }
        }
        V oldValue = null;
        if (i < size) {
            oldValue = entry.getValue();
            entry.setValue(value);
        } else {
            list.add(new Entry<>(key, value));
        }
        return oldValue;
    }
}