/**
 * File : Hashtable.as
 * @author 이경빈 (Kevin Lee)
 * @version $Revision: 1.1 $, $Date: 2007/03/18 22:10:14 $
 */
package godai.util.dictionary
{
 import mx.collections.ArrayCollection;
 
 /**
  * 
  * 
  */
 public class Hashtable
 {
  private var table:Object;
  private var keyArray:Array;
  private var valueArray:Array;
  
  public function Hashtable() {
   table = new Object();
   keyArray = new Array();
   valueArray = new Array();
  }
  
  public function clear():void {
   table = new Object();
   keyArray = new Array();
   valueArray = new Array();
  }
  
  public function clone():Hashtable {
   var result:Hashtable = new Hashtable();
   
   for (var i:int = 0; i < keyArray.length; i++) {
    var key:Object = keyArray[i];
    var value:Object = getValue(key);
    
    result.put(key, value);
   }
   
   return result;
  }
  
  public function containsKey(key:Object):Boolean {
   if (getValue(key) == undefined) {
    return false;
   } else if ( getValue(key) == null) {
    return false;
   } else {
    return true;
   }
  }
  
  public function containsValue(value:Object):Boolean {
   // 귀찮아서 미구현 ;;
  }
   
  public function getKeyArray():Array {
   return keyArray;
  }
  
  public function getValueArray():Array {
   return valueArray;
  }
  
  public function getValue(key:Object):Object {
   
   if (key == null) {
    throw new Error("[Hashtable] key is null!");
    return null;
   }
   
   return table[key.toString()];
  }
  
  public function isEmpty():Boolean {
   if (keyArray.length == 0) {
    return true;
   } else {
    return false;
   }
  }
  
  public function put(key:Object, value:Object):Object {
   
   if (key == null) {
    throw new Error("[Hashtable] key is null!");
    return null;
   }
   
   if (value == null) {
    throw new Error("[Hashtable] value is null!");
    return null;
   }
   
   var result:Object = getValue(key);
   
   if (result == null) {
    keyArray.push(key);
   } else {
    var tempIdx:int = findIdx(valueArray, value);
    
    if (tempIdx < 0) {
     // ASSERTION tempIdx must > -1
    } else {
     valueArray.splice(tempIdx, 1);
    }
    
    valueArray.push(value);
   }
   
   table[key.toString()] = value;
   
   return result;
  }
  
  public function remove(key:Object):Object {
   var removedValue:Object = getValue(key);
   
   if (removedValue == null) {
    return removedValue;
   }
   
   delete table[key.toString()];
   
    var removedKeyIdx:int = findIdx(keyArray, key);
    keyArray.splice(removedKeyIdx, 1);
    
   var removedValueIdx:int = findIdx(valueArray, removedValue);
   valueArray.splice(removedValueIdx, 1);
   
   return removedValue;
  }
  
   private function findIdx(arr:Array, value:Object):int {
    for (var i:int = 0; i < arr.length; i++) {
     if (value === arr[i]) {
      return i;
     }
    }
    
    return -1;
   }
  
 }
}