package cz.cuni.amis.pogamut.base.communication.worldview.object;
   
   import java.io.Serializable;
   import java.util.HashMap;
   import java.util.Map;
   
   import cz.cuni.amis.utils.exception.PogamutException;
   import cz.cuni.amis.utils.token.Token;
   import cz.cuni.amis.utils.token.Tokens;
  
  /**
   * Interface that is returning an unique id of the world object. The id must be unique
   * among all the objects in the world.
   * <p><p>
   * Every implementations MUST implement equals() and hashCode() correctly as we will use this inside
   * hashmaps/sets.
   * 
   * @author Jimmy
   */
  public class WorldObjectId implements Serializable {
  	
  	/**
  	 * Unique representation of this id, contains ints that uniquely identifies it.
  	 */
  	protected Token token;
  	
  	/**
  	 * Whether the id wolds 'long' inside {@link WorldObjectId#token}.
  	 */
  	protected boolean isLong;
  	
  	/**
  	 * Whether the id wolds 'double' inside {@link WorldObjectId#token}.
  	 */
  	protected boolean isDouble;
  	
  	/**
  	 * Instantiates a new object with id of 'name'.
  	 * @param name
  	 */
  	protected WorldObjectId(String name) {
  		this.token = Tokens.get(name);
  		isLong = false;
  		isDouble = false;
  	}
  	
  	/**
  	 * Instantiates a new object with id of 'id'.
  	 * @param id
  	 */
  	protected WorldObjectId(long id) {
  		this.token = Tokens.get(id);
  		isLong = true;
  		isDouble = false;
  	}
  	
  	/**
  	 * Instantiates a new object with id of 'id'.
  	 * @param id
  	 */
  	protected WorldObjectId(double id) {
  		this.token = Tokens.get(id);
  		isLong = false;
  		isDouble = true;
  	}
  	
  	protected WorldObjectId(Token token) {
  		this.token = token;
  	}
  	
  	@Override
  	public int hashCode() {
  		return token.hashCode();
  	}
  	
  	@Override
  	public boolean equals(Object o) {
  		if (o == this) return true; // early-success
  		if (o == null) return false;
  		if (!(o instanceof WorldObjectId)) return false;
  		return token.equals(((WorldObjectId)o).token);
  	}
  
  	/**
  	 * Always returns a string representation of the ID.
  	 * @return
  	 */
  	public String getStringId() {
  		return token.getToken();
  	}
  	
  	/**
  	 * Whether the id holds a numeric value (i.e., it is either {@link WorldObjectId#isLongId()} or {@link WorldObjectId#isDoubleId()}).
  	 * @return
  	 */
  	public boolean isNumericId() {
  		return isLong || isDouble;
  	}
  	
 	/**
 	 * Whether the id is a long one.
 	 * @return
 	 */
 	public boolean isLongId() {
 		return isLong;
 	}
 	
 	/**
 	 * Whether the is is a double one.
 	 * @return
 	 */
 	public boolean isDoubleId() {
 		return isDouble;
 	}	
 	
 	/**
 	 * Returns id as 'long', only iff {@link WorldObjectId#isLongId()}, otherwise it raises a {@link PogamutException}.
 	 * 
 	 * @return long
 	 */
 	public long getLongId() {
         if (!isLong) {
         	try {
         		long result = Long.parseLong(token.getToken());
         		isLong = true;
         		return result;
         	} catch (Exception e) {
         		throw new PogamutException("Id does not hold long value! Id: " + this, this);
         	}
         }
         return Long.parseLong(token.getToken());
 	}
 	
 	/**
 	 * Returns id as 'double', only iff {@link WorldObjectId#isDoubleId()}, otherwise it raises a {@link PogamutException}.
 	 * 
 	 * @return long
 	 */
 	public double getDoubleId() {
         if (!isDouble) {
         	try {
         		double result = Double.parseDouble(token.getToken());
         		isDouble = true;
         		return result;
         	} catch (Exception e) {
         		throw new PogamutException("Id does not hold double value! Id: " + this, this);
         	}        	
         }
         return Double.parseDouble(token.getToken());
 	}
 	
 	/**
 	 * Returns string representation of the id, format: WorldObjectId[id] 
 	 * 
 	 * @return string representation of this object
 	 */
 	@Override
 	public String toString() {
 		return "WorldObjectId["+getStringId()+"]";
 	}
 
 	/**
 	 * Map that serves for translation of WorldObjectIds...
 	 */
 	private static Map<String, WorldObjectId> map  = new HashMap<String, WorldObjectId>();
 	
 	/**
 	 * Returns shared instance of the {@link WorldObjectId} for 'name'. If no {@link WorldObjectId} exists for 'name',
 	 * new one is created.
 	 * <p><p>
 	 * THREAD-SAFE!
 	 * 
 	 * @param name
 	 * @return
 	 */
 	public static WorldObjectId get(String name) {
 		if (name == null) throw new PogamutException("Could not return a WorldObjectId for 'null'!", WorldObjectId.class);
 		WorldObjectId id = null;
 		id = map.get(name);
 		if (id != null) return id;
 		synchronized(map) {
 			id = map.get(name);
 			if (id != null) return id;
 			id = new WorldObjectId(name);
 			map.put(name, id);
 		}
 		return id;
 	}
 	
 	/**
 	 * Returns shared instance of the {@link WorldObjectId} for 'objId'. If no {@link WorldObjectId} exists for 'objId',
 	 * new one is created.
 	 * <p><p>
 	 * THREAD-SAFE!
 	 * 
 	 * @param name
 	 * @return
 	 */
 	public static WorldObjectId get(long objId) {
 		return get(String.valueOf(objId));
 	}
 	
 	/**
 	 * Returns shared instance of the {@link WorldObjectId} for 'objId'. If no {@link WorldObjectId} exists for 'objId',
 	 * new one is created.
 	 * <p><p>
 	 * THREAD-SAFE!
 	 * 
 	 * @param name
 	 * @return
 	 */
 	public static WorldObjectId get(double objId) {
 		return get(String.valueOf(objId));
 	}
 	
 }