package org.apache.samoa.instances;

/*
 * #%L
 * SAMOA
 * %%
 * Copyright (C) 2014 - 2015 Apache Software Foundation
 * %%
 * Licensed 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.
 * #L%
 */

import java.io.Serializable;

public class Range implements Serializable {

  //Only works for ranges "start-end"
  private int start = 0;
  private int end = 0;
  private int upperLimit = 0;
  private final String rangeText;

  public Range(String range) {
    this.rangeText = range;
    //this.setRange(range); //needs upperLimit
  }

  /**
   * Sets the range from a string representation.
   *
   * @param range the start and end string
   *
   */
  public void setRange(String range) {
    String single = range.trim();
    int hyphenIndex = range.indexOf('-');

    if (hyphenIndex > 0) {
      this.start = rangeSingle(range.substring(0, hyphenIndex));
      this.end = rangeSingle(range.substring(hyphenIndex + 1));
    } else {
      int number = rangeSingle(range);
      if (number >= 0) { // first n attributes
        this.start = 0;
        this.end = number;
      } else { // last n attributes
        this.start = this.upperLimit + number > 0 ? this.upperLimit + number : 0;
        this.end = this.upperLimit - 1;
      }
    }
  }

  /**
   * Translates a single string selection into it's internal 0-based
   * equivalent.
   *
   * @param single the string representing the selection (eg: 1 first last)
   * @return the number corresponding to the selected value
   */
  protected /*@pure@*/ int rangeSingle(/*@non_null@*/String singleSelection) {

    String single = singleSelection.trim();
    if (single.toLowerCase().equals("first")) {
      return 0;
    }
    if (single.toLowerCase().equals("last") || single.toLowerCase().equals("-1")) {
      return -1;
    }
    int index = Integer.parseInt(single);
    if (index >= 1) { //Non for negatives
      index--;
    }
    return index;
  }

  boolean isInRange(int value) {
    boolean ret = false;
    if (value >= start && value <= end) {
      ret = true;
    }
    return ret;
  }

  int getSelectionLength() {
    return end - start + 1;
  }

  public void setUpper(int attributeNumber) {
    this.upperLimit = attributeNumber;
    this.setRange(this.rangeText);
  }

  //JD
  public int getStart() {
    return start;
  }

  //JD

  public int getEnd() {
    return end;
  }

}