/**
    * Copyright 2005-2011 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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 org.kuali.rice.kns.datadictionary.validation.charlevel;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.krad.datadictionary.exporter.ExportMap;
  import org.kuali.rice.krad.datadictionary.validation.CharacterLevelValidationPattern;
  
  import java.util.regex.Pattern;
  
  /**
   * Pattern for matching any character in the given list (String)
   * 
   * 
   */
  public class CharsetValidationPattern extends CharacterLevelValidationPattern {
      protected String validChars;
  
      /**
       * @return String containing all valid chars for this charset
       */
      public String getValidChars() {
          return validChars;
      }
  
      /**
       * @param validChars for this charset
       */
      public void setValidChars(String validChars) {
          if (StringUtils.isEmpty(validChars)) {
              throw new IllegalArgumentException("invalid (empty) validChars");
          }
  
          this.validChars = validChars;
      }
  
  
      /**
       * Escapes every special character I could think of, to limit potential misuse of this pattern.
       * 
       * @see org.kuali.rice.krad.datadictionary.validation.ValidationPattern#getRegexString()
       */
      protected String getRegexString() {
          if (StringUtils.isEmpty(validChars)) {
              throw new IllegalStateException("validChars is empty");
          }
  
          // filter out and escape chars which would confuse the pattern-matcher
          Pattern filteringChars = Pattern.compile("([\\-\\[\\]\\{\\}\\$\\.\\^\\(\\)\\*\\&\\|])");
          String filteredChars = filteringChars.matcher(validChars).replaceAll("\\\\$1");
  
          StringBuffer regexString = new StringBuffer("[");
          regexString.append(filteredChars);
          if (filteredChars.endsWith("\\")) {
              regexString.append("\\");
          }
          regexString.append("]");
  
          return regexString.toString();
      }
  
  
      /**
       * @see org.kuali.rice.krad.datadictionary.validation.CharacterLevelValidationPattern#extendExportMap(org.kuali.bo.datadictionary.exporter.ExportMap)
       */
      public void extendExportMap(ExportMap exportMap) {
          exportMap.set("type", "charset");
  
          exportMap.set("validChars", getValidChars());
      }
  
  	/**
  	 * This overridden method ...
  	 * 
  	 * @see org.kuali.rice.krad.datadictionary.validation.CharacterLevelValidationPattern#getValidationErrorMessageParameters(java.lang.String, java.lang.String)
  	 */
  	@Override
  	public String[] getValidationErrorMessageParameters(String attributeLabel) {
  		// build character list
  		StringBuilder buf = new StringBuilder();
  		for (int i = 0; i < validChars.length(); i++) {
  			buf.append(validChars.charAt(i));
  			if (i != validChars.length() - 1) {
  				buf.append(", ");
  			}
  		}
 		String characterList = buf.toString();
 		
 		if (getMaxLength() != -1) {
 			return new String[] {attributeLabel, String.valueOf(getMaxLength()), characterList};
 		}
 		if (getExactLength() != -1) {
 			return new String[] {attributeLabel, String.valueOf(getExactLength()), characterList};
 		}
 		return new String[] {attributeLabel, "0", characterList};
 	}
 }