/*
    * This file is part of Waarp Project (named also Waarp or GG).
    *
    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
    * individual contributors.
    *
    *  All Waarp Project is free software: you can redistribute it and/or
    * modify it under the terms of the GNU General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or (at your
   * option) any later version.
   *
   * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
   * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along with
   * Waarp . If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.waarp.openr66.dao;
  
  public class Filter {
    public static final String LIKE = "LIKE";
    public static final String BETWEEN = "BETWEEN";
    public static final String IS_NOT_NULL = "IS NOT NULL";
    public static final String IN = "IN";
    public static final String SPECIFIC_SQL = "SPEC_SQL";
    private static final byte B_NONE = 'n';
    private static final byte B_SINGLE = 's';
    private static final byte B_MULTIPLE = 'm';
    public final String key;
    public final String operand;
    public final Object value;
    private final int nbArgs;
    private final byte specialOperand;
  
    public Filter(final String key, final String operand,
                  final Object... values) {
      this.key = key;
      this.operand = operand;
      nbArgs = values == null? 0 : values.length;
      if (nbArgs == 0) {
        this.value = null;
        specialOperand = B_NONE;
      } else if (nbArgs == 1) {
        this.value = values[0];
        specialOperand = B_SINGLE;
      } else {
        this.value = values;
        specialOperand = B_MULTIPLE;
      }
    }
  
    /**
     * @return the number of values for the operand
     */
    public final int nbAdditionnalParams() {
      return nbArgs;
    }
  
    /**
     * Helper
     *
     * @param builder
     *
     * @return the associated value
     */
    public final Object append(final StringBuilder builder) {
      if (SPECIFIC_SQL.equalsIgnoreCase(operand)) {
        builder.append(key);
      } else if (nbArgs == 0) {
        builder.append(key).append(' ').append(operand).append(" ");
      } else if (nbArgs == 1) {
        builder.append(key).append(' ').append(operand).append(" ? ");
      } else {
        if (BETWEEN.equalsIgnoreCase(operand)) {
          // Object is a Object[2]
          builder.append(key).append(' ').append(BETWEEN).append(" ? AND ? ");
        } else if (IN.equalsIgnoreCase((operand))) {
          // Object is a Object[n]
          builder.append(key).append(' ').append(IN).append("(?");
          for (int i = 1; i < nbArgs; i++) {
            builder.append(", ?");
          }
          builder.append(") ");
        } else {
          throw new IllegalArgumentException(
              "Command seems to not support multiple arguments: " + operand);
        }
      }
      return value;
    }
  }