content: /*
   * 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.calcite.adapter.splunk.util;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Utility methods for encoding and decoding strings for Splunk REST calls.
   */
  public class StringUtils {
    private StringUtils() {}
  
    public static StringBuilder encodeList(
        List<? extends CharSequence> list, char delim) {
      StringBuilder result = new StringBuilder();
      boolean first = true;
      for (CharSequence cs : list) {
        if (!first) {
          result.append(delim);
        }
        int len = cs.length();
        for (int i = 0; i < len; ++i) {
          char c = cs.charAt(i);
          if (c == delim) {
            result.append('\\');
          }
          result.append(c);
        }
        first = false;
      }
      return result;
    }
  
    public static List<String> decodeList(CharSequence encoded, char delim) {
      List<String> list = new ArrayList<>();
      int len = encoded.length();
      int start = 0;
      int end = 0;
      boolean hasEscapedDelim = false;
      char p = '\0';
      char c = '\0';
      for (int i = 0; i < len; i++, ++end) {
        p = c;
        c = encoded.charAt(i);
        if (c == delim) {
          if (p == '\\') {
            hasEscapedDelim = true;
          } else {
            if (!hasEscapedDelim) {
              list.add(encoded.subSequence(start, end).toString());
            } else {
              StringBuilder sb = new StringBuilder(end - start);
              char a = '\0';
              char b = '\0';
              for (int j = start; j < end; ++j) {
                b = a;
                a = encoded.charAt(j);
                if (b == '\\' && a != delim) {
                  sb.append(b);
                }
                if (a != '\\') {
                  sb.append(a);
                }
              }
              list.add(sb.toString());
            }
            start = end + 1;
            hasEscapedDelim = false;
          }
        }
      }
  
      if (!hasEscapedDelim) {
        list.add(encoded.subSequence(start, end).toString());
      } else {
        StringBuilder sb = new StringBuilder(end - start);
        char a = '\0';
        char b = '\0';
        for (int j = start; j < end; ++j) {
          b = a;
          a = encoded.charAt(j);
          if (b == '\\' && a != delim) {
            sb.append(b);
          }
          if (a != '\\') {
            sb.append(a);
          }
        }
        list.add(sb.toString());
      }
  
      return list;
    }
  
    public static boolean parseBoolean(
        String str, boolean defaultVal, boolean missingVal) {
      if (str == null || str.isEmpty()) {
        return missingVal;
      }
      if (str.equalsIgnoreCase("t")
          || str.equalsIgnoreCase("true")
          || str.equalsIgnoreCase("yes")
          || str.equals("1")) {
        return true;
      }
      if (str.equalsIgnoreCase("f")
          || str.equalsIgnoreCase("false")
          || str.equalsIgnoreCase("no")
          || str.equals("0")) {
        return false;
      }
      return defaultVal;
    }
  
  
    public static void main(String[] args) {
      List<String> list = new ArrayList<>();
      list.add("test");
      list.add("test,with,comma");
      list.add("");
      list.add(",");
  
      System.out.println("=============");
  
      StringBuilder sb = encodeList(list, ',');
      System.out.println(sb);
  
      list.clear();
      list = decodeList(sb, ',');
      for (String s : list) {
        System.out.println(s);
      }
      System.out.println("=============");
    }
  
    public static Logger getClassTracer(Class clazz) {
      return LoggerFactory.getLogger(clazz);
    }
  }
  