/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements. See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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.apache.logging.log4j.core.layout;
  
  import java.nio.charset.Charset;
  
  import org.apache.commons.csv.CSVFormat;
  import org.apache.commons.csv.QuoteMode;
  import org.apache.logging.log4j.core.config.Configuration;
  
  /**
   * A superclass for Comma-Separated Value (CSV) layouts.
   *
   * Depends on Apache Commons CSV 1.2.
   *
   * @since 2.4
   */
  public abstract class AbstractCsvLayout extends AbstractStringLayout {
  
      protected static final String DEFAULT_CHARSET = "UTF-8";
      protected static final String DEFAULT_FORMAT = "Default";
      private static final String CONTENT_TYPE = "text/csv";
  
      protected static CSVFormat createFormat(final String format, final Character delimiter, final Character escape,
              final Character quote, final QuoteMode quoteMode, final String nullString, final String recordSeparator) {
          CSVFormat csvFormat = CSVFormat.valueOf(format);
          if (isNotNul(delimiter)) {
              csvFormat = csvFormat.withDelimiter(delimiter);
          }
          if (isNotNul(escape)) {
              csvFormat = csvFormat.withEscape(escape);
          }
          if (isNotNul(quote)) {
              csvFormat = csvFormat.withQuote(quote);
          }
          if (quoteMode != null) {
              csvFormat = csvFormat.withQuoteMode(quoteMode);
          }
          if (nullString != null) {
              csvFormat = csvFormat.withNullString(nullString);
          }
          if (recordSeparator != null) {
              csvFormat = csvFormat.withRecordSeparator(recordSeparator);
          }
          return csvFormat;
      }
  
      private static boolean isNotNul(final Character character) {
          return character != null && character.charValue() != 0;
      }
  
      private final CSVFormat format;
  
      protected AbstractCsvLayout(final Configuration config, final Charset charset, final CSVFormat csvFormat,
              final String header, final String footer) {
          super(config, charset,
                  PatternLayout.newSerializerBuilder().setConfiguration(config).setPattern(header).build(),
                  PatternLayout.newSerializerBuilder().setConfiguration(config).setPattern(footer).build());
          this.format = csvFormat;
      }
  
      @Override
      public String getContentType() {
          return CONTENT_TYPE + "; charset=" + this.getCharset();
      }
  
      public CSVFormat getFormat() {
          return format;
      }
  }