/*
 * The MIT License
 * Copyright © 2014-2019 Ilkka Seppälä
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package com.iluwatar.intercepting.filter;

/**
 * Base class for order processing filters. Handles chain management.
 */
public abstract class AbstractFilter implements Filter {

  private Filter next;

  public AbstractFilter() {
  }

  public AbstractFilter(Filter next) {
    this.next = next;
  }

  @Override
  public void setNext(Filter filter) {
    this.next = filter;
  }

  @Override
  public Filter getNext() {
    return next;
  }

  @Override
  public Filter getLast() {
    Filter last = this;
    while (last.getNext() != null) {
      last = last.getNext();
    }
    return last;
  }

  @Override
  public String execute(Order order) {
    if (getNext() != null) {
      return getNext().execute(order);
    } else {
      return "";
    }
  }
}
