/*
    * Copyright 2004-5 the original author or authors.
    * 
    * Licensed under the Apache License, Version 2.0 (the "License"); you may not
    * use this file except in compliance with the License. You may obtain a copy of
    * the License at
    * 
    * http://www.apache.org/licenses/LICENSE-2.0
    * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations under
   * the License.
   */package net.sf.morph.util;
  
  import java.lang.reflect.Array;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.List;
  
  import net.sf.morph.Morph;
  
  /**
   * @author Matt Sgarlata
   * @since Mar 11, 2005
   */
  public class StringUtils {
  	
  //	private static final DecoratedConverter LIST_CONVERTER = new SimpleDelegatingTransformer();
  
  	public static int numOccurrences(String toSearch, String searchFor) {
  		if (toSearch == null && searchFor == null) {
  			return 0;
  		}
  		if (searchFor == null || searchFor.length() == 0) {
  			return 0;
  		}
  		int matchingIndex = 0;
  		int numOccurrences = 0;
  		for (int i=0; i<toSearch.length(); i++) {
  			if (toSearch.charAt(i) == searchFor.charAt(matchingIndex)) {
  				if (matchingIndex == searchFor.length() -1) {
  					matchingIndex = 0;
  					numOccurrences++;
  				}
  				else {
  					matchingIndex++;
  				}
  			}
  		}
  		return numOccurrences;
  	}
  
  	public static String repeat(String str, int repititions) {
  		int size = repititions * (str == null ? 0 : str.length());
  		StringBuffer buffer = new StringBuffer(size);
  		for (int i=0; i<repititions; i++) {
  			buffer.append(str);
  		}
  		return buffer.toString();
  	}
  
  	public static String englishJoin(Object values) {
  		if (values == null) {
  			return null;
  		}
  		StringBuffer buffer = new StringBuffer();
  		int length = Array.getLength(values);
  		for (int i = 0; i < length; i++) {
  			buffer.append(Array.get(values, i));
  			if (i < length - 2) {
  				buffer.append(", ");
  			}
  			if (i == length - 2) {
  				buffer.append(" and ");
  			}
  		}
  		return buffer.toString();
  	}
  
  	public static String englishJoin(Collection values) {
  		return englishJoin(values.toArray(new Object[values.size()]));
  	}
  
  	public static String removeWhitespace(String expression) {
  		if (expression == null) {
  			return null;
  		}
  		
  		// first make sure there is whitespace.  Usually there won't be so we
  		// can save ourselves from creating a new StringBuffer and String
  		for (int i=0; i<expression.length(); i++) {
  			if (Character.isWhitespace(expression.charAt(i))) {
  				return constructStringWithoutWhitespace(expression);
  			}
  		}
  		
  		return expression;		
 	}
 	
 	private static String constructStringWithoutWhitespace(String expression) {
 		StringBuffer buffer = new StringBuffer(expression.length());
 		for (int i=0; i<expression.length(); i++) {
 			if (!Character.isWhitespace(expression.charAt(i))) {
 				buffer.append(expression.charAt(i));
 			}
 		}
 		return buffer.toString();
 	}
 
 	public static String join(Object object, String separator) {
 		if (object == null) {
 			return null;
 		}
 		
 		//build the metric id string
 		StringBuffer idBuff = new StringBuffer();
 		boolean firstIteration = true;
 		Collection collection = (Collection) Morph.convert(List.class, object);
 		for (Iterator iter = collection.iterator(); iter.hasNext();) {
 			if (firstIteration) {
 				firstIteration = false;
 			}
 			else {
 				idBuff.append(separator);
 			}
 			idBuff.append(iter.next());
 		}
 		return idBuff.toString();
 	}
 
 	public static String join(Object object) {
 		return join(object, ", ");
 	}
 
 }