package com.github.mygreen.supercsv.cellprocessor.constraint;
   
   import java.util.Optional;
   
   import org.supercsv.cellprocessor.ift.CellProcessor;
   
   import com.github.mygreen.supercsv.annotation.constraint.CsvUniqueHashCode;
   import com.github.mygreen.supercsv.builder.Configuration;
   import com.github.mygreen.supercsv.builder.FieldAccessor;
  import com.github.mygreen.supercsv.cellprocessor.ConstraintProcessorFactory;
  import com.github.mygreen.supercsv.cellprocessor.format.TextFormatter;
  
  /**
   * アノテーション{@link CsvUniqueHashCode}をハンドリングして、CellProcessorの{@link UniqueHashCode}を作成する。
   * 
   * @since 2.0
   * @author T.TSUCHIE
   *
   */
  public class UniqueHashCodeFactory<T> implements ConstraintProcessorFactory<CsvUniqueHashCode> {
      
      @Override
      public Optional<CellProcessor> create(final CsvUniqueHashCode anno, final Optional<CellProcessor> next,
              final FieldAccessor field, final TextFormatter<?> formatter, final Configuration config) {
          
          @SuppressWarnings("unchecked")
          final TextFormatter<T> typeFormatter = (TextFormatter<T>)formatter;
          
          final UniqueHashCode<T> processor = next.map(n -> new UniqueHashCode<T>(typeFormatter, n))
                  .orElseGet(() -> new UniqueHashCode<T>(typeFormatter));
          
          processor.setValidationMessage(anno.message());
          
          return Optional.of(processor);
      }
      
  }