/*
    * Copyright 2004-2009 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 org.springmodules.validation.valang.predicates;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.Map;
  
  import org.apache.commons.collections.Predicate;
  import org.springframework.beans.BeanWrapper;
  import org.springframework.beans.BeanWrapperImpl;
  import org.springframework.util.Assert;
  import org.springframework.util.CollectionUtils;
  import org.springframework.util.StringUtils;
  import org.springframework.validation.Errors;
  import org.springmodules.validation.valang.functions.Function;
  
  
  /**
   * <p>Validation rule implementation that will validate a target
   * bean an return an error message is the validation fails.
   *
   * @author Steven Devijver
   * @since 23-04-2005
   */
  public class BasicValidationRule implements ValidationRule {
  
      private final Predicate predicate;
      private final Predicate wherePredicate;
      private final String defaultPropertyName;
      private final String errorMessage;
      private final String errorKey;
      private final Collection<Function> errorArgs;
  
      /**
       * Constructor.
       * 
       * @param       field           Default property/field name.
       * @param       predicate       Predicate used for comparison.
       * @param       errorMessage    Default error message.
       */
      public BasicValidationRule(String defaultPropertyName, Predicate predicate, String errorMessage) {
          Assert.notNull(defaultPropertyName, "Field parameter must not be null.");
          Assert.notNull(predicate, "Predicate parameter must not be null.");
          Assert.notNull(errorMessage, "Error message parameter must not be null.");
  
          this.defaultPropertyName = defaultPropertyName;
          this.predicate = predicate;
          this.wherePredicate = null;
          this.errorMessage = errorMessage;
          this.errorKey = null;
          this.errorArgs = null;
      }
  
      /**
       * Constructor.
       * 
       * @param       field               Default property/field name.
       * @param       predicate           Predicate used for comparison.
       * @param       wherePredicate      Where predicate used for whether or not validation should be performed.
       * @param       errorKey            Message resource key for the error.
       * @param       errorMessage        Default error message.
       * @param       errorArgs           Error message argument.
       */
      public BasicValidationRule(String defaultPropertyName, Predicate predicate, Predicate wherePredicate,
                                 String errorKey, String errorMessage, Collection<Function> errorArgs) {
          Assert.notNull(defaultPropertyName, "Field parameter must not be null.");
          Assert.notNull(predicate, "Predicate parameter must not be null.");
          Assert.notNull(errorMessage, "Error message parameter must not be null.");
  
          this.defaultPropertyName = defaultPropertyName;
          this.predicate = predicate;
          this.wherePredicate = wherePredicate;
          this.errorMessage = errorMessage;
          this.errorKey = errorKey;
          this.errorArgs = errorArgs;
          
      }
  
      /**
       * Gets predicate.
       */
      public Predicate getPredicate() {
          return this.predicate;
     }
 
 //    /**
 //     * Sets predicate.
 //     */
 //    private void setPredicate(Predicate predicate) {
 //        Assert.notNull(predicate, "Predicate parameter must not be null.");
 //
 //        this.predicate = predicate;
 //    }
 
     /**
      * Gets error message.
      */
     public String getErrorMessage() {
         return this.errorMessage;
     }
 
 //    /**
 //     * Sets error message.
 //     */
 //    private void setErrorMessage(String errorMessage) {
 //        Assert.notNull(errorMessage, "Error message parameter must not be null.");
 //
 //        this.errorMessage = errorMessage;
 //    }
 
     /**
      * Gets field.
      */
     public String getField() {
         return this.defaultPropertyName;
     }
 
 //    /**
 //     * Sets field.
 //     */
 //    private void setField(String field) {
 //        Assert.notNull(field, "Field parameter must not be null.");
 //
 //        this.defaultPropertyName = field;
 //    }
 
 //    private void setErrorKey(String errorKey) {
 //        this.errorKey = errorKey;
 //    }
 
     /**
      * Gets error key.
      */
     public String getErrorKey() {
         return this.errorKey;
     }
 
 //    private void setErrorArgs(Collection errorArgs) {
 //        this.errorArgs = errorArgs;
 //    }
 
     /**
      * Get error args.
      */
     public Collection<Function> getErrorArgs() {
         return this.errorArgs;
     }
 
     /**
      * Validates bean and records any errors.
      */
     public void validate(Object target, Errors errors) {
         // if the where predicate isn't null continue, 
         // otherwise only continue evaluate where predicate evaluates to true
         if ((wherePredicate != null ? wherePredicate.evaluate(target) : true)) {
             if (!getPredicate().evaluate(target)) {
                 // Take into account error key and error args for localization
                 if (StringUtils.hasLength(getErrorKey())) {
                     if (!CollectionUtils.isEmpty(getErrorArgs())) {
                         Collection<String> tmpColl = new ArrayList<String>();
 
                         for (Function errorArgFunction : getErrorArgs()) {
                             tmpColl.add(errorArgFunction.getResult(target).toString());
                         }
 
                         errors.rejectValue(getField(), getErrorKey(), tmpColl.toArray(), getErrorMessage());
                     } else {
                         errors.rejectValue(getField(), getErrorKey(), getErrorMessage());
                     }
                 } else {
                     errors.rejectValue(getField(), getField(), getErrorMessage());
                 }    
             }
         }
     }
 
 
 }