package com.atlassian.sal.api.validate;
   
   import com.atlassian.annotations.PublicApi;
   import com.google.common.collect.ImmutableSet;
   
   import java.util.Collections;
   import javax.annotation.Nonnull;
   
   import static com.google.common.base.Preconditions.checkNotNull;
  
  @SuppressWarnings ("UnusedDeclaration")
  @PublicApi
  /**
   * The outcome of a validation check.
   * @since 3.0
   */
  public class ValidationResult
  {
      private static final ValidationResult VALID = new ValidationResult(Collections.<String>emptySet());
  
      private final ImmutableSet<String> errorMessages;
  
      private final ImmutableSet<String> warningMessages;
  
      private ValidationResult(@Nonnull final Iterable<String> errorMessages)
      {
          this(errorMessages, Collections.<String>emptySet());
      }
  
      private ValidationResult(@Nonnull final Iterable<String> errorMessages, @Nonnull final Iterable<String> warningMessages)
      {
          checkNotNull(errorMessages, "errorMessages");
          checkNotNull(warningMessages, "warningMessages");
          this.errorMessages = ImmutableSet.copyOf(errorMessages);
          this.warningMessages = ImmutableSet.copyOf(warningMessages);
      }
  
      public static ValidationResult valid()
      {
          return VALID;
      }
  
      public static ValidationResult withErrorMessages(@Nonnull final Iterable<String> errorMessages)
      {
          return new ValidationResult(errorMessages);
      }
  
      public static ValidationResult withWarningMessages(@Nonnull final Iterable<String> warningMessages)
      {
          return new ValidationResult(Collections.<String>emptySet(), warningMessages);
      }
  
      public static ValidationResult withErrorAndWarningMessages(@Nonnull final Iterable<String> errorMessages, @Nonnull final Iterable<String> warningMessages)
      {
          return new ValidationResult(errorMessages, warningMessages);
      }
  
      /**
       * Return true if the validation passed, false if there were errors. (Note warnings do not cause this method to
       * return false).
       *
       * @return true if the validation passed, false if there were errors.
       * @see #hasWarnings()
       */
      public boolean isValid()
      {
          return errorMessages.isEmpty();
      }
  
      /**
       * Return true if the validation added error messages.
       *
       * @return true if the validation failed with error messages.
       */
      public boolean hasErrors()
      {
          return !errorMessages.isEmpty();
      }
  
      /**
       * Return true if the validation added warning messages.
       *
       * @return true if the validation failed with warning messages.
       */
      public boolean hasWarnings()
      {
          return !warningMessages.isEmpty();
      }
  
      /**
       * Returns error messages.
       * <p/>
       * These should normally be localised to the end user's locale. This will never be null, but may be empty.
       *
       * @return validation error messages, could be empty but not null.
       */
      @Nonnull
      public Iterable<String> getErrorMessages()
      {
         return errorMessages;
     }
 
     /**
      * Returns warnings messages.
      * <p/>
      * These should normally be localised to the end user's locale. This will never be null, but may be empty.
      *
      * @return validation warning messages, could be empty but not null.
      */
     @Nonnull
     public Iterable<String> getWarningMessages()
     {
         return warningMessages;
     }
 }