package cz.cuni.amis.utils.maps;
   
   import java.util.Collection;
   import java.util.HashMap;
   import java.util.Map;
   import java.util.Set;
   
   public class CountIntMap<KEY> implements Map<KEY, Integer>{
   	
  	private HashMap<KEY, Integer> counts = new HashMap<KEY, Integer>();
  	
  	@Override
  	public void clear() {
  		counts.clear();
  	}
  	
  	@Override
  	public Set<KEY> keySet() { 
  		return counts.keySet();
  	}
  
  	@Override
  	public Set<Entry<KEY, Integer>> entrySet() {
  		return counts.entrySet();
  	}
  	
  	@Override
  	public Collection<Integer> values() {
  		return counts.values();
  	}
  	
  	@Override
  	public Integer get(Object key) {
  		Integer value = counts.get(key);
  		if (value == null) {
  			counts.put((KEY) key, 0);
  			return 0;
  		}
  		return value;
  	}
  	
  	@Override
  	public Integer remove(Object key) {
  		return counts.remove(key);
  	}
  	
  	/**
  	 * Sets key to 'value' returning previously associated value (alias for {@link CountIntMap#put(Object, Integer)}).
  	 * @param key
  	 * @param value
  	 * @return
  	 */
  	public int set(KEY key, int value) {
  		return counts.put(key, value);
  	}
  	
  	/**
  	 * Increase 'key' +1 returning previous value.
  	 * @param key
  	 * @return
  	 */
  	public int increase(KEY key) {
  		return increase(key, 1);
  	}
  	
  	/**
  	 * Increase 'key' +amount returning previous value.
  	 * @param key
  	 * @return
  	 */
  	public int increase(KEY key, int amount) {
  		return counts.put(key, get(key) + amount);
  	}
  
  	/**
  	 * Increase 'key' -1 returning previous value.
  	 * @param key
  	 * @return
  	 */
  	public int decrease(KEY key) {
  		return increase(key, -1);
  	}
  	
  	/**
  	 * Increase 'key' -amount returning previous value.
  	 * @param key
  	 * @return
  	 */
  	public int decrease(KEY key, int amount) {
  		return increase(key, -amount);
  	}
  
  	/**
  	 * Multiplies 'key' with amount returning previous value.
  	 * @param key
  	 * @return
  	 */
  	public int multi(KEY key, int amount) {
  		return counts.put(key, get(key) * amount);
 	}
 
 	@Override
 	public boolean containsKey(Object key) {
 		return counts.containsKey(key);
 	}
 
 	@Override
 	public boolean containsValue(Object value) {
 		return counts.containsValue(value);
 	}
 
 	@Override
 	public boolean isEmpty() {
 		return counts.isEmpty();
 	}
 
 	@Override
 	public Integer put(KEY key, Integer value) {
 		return counts.put(key, value);
 	}
 
 	@Override
 	public void putAll(Map<? extends KEY, ? extends Integer> m) {
 		counts.putAll(m);
 	}
 
 	@Override
 	public int size() {
 		return counts.size();
 	}
 
 }