/*
 *    This program 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 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program 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 this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package eti.bi.alphaminer.vo;

import java.util.Comparator;

/**
 * CaseInformationComparator is a class used to set CaseInformation stored 
 * in a CaseInfoList based on different criteria.
 */
public class CaseInformationComparator implements Comparator {

	/**
	 * Different kind of sorting criteria
	 */
	public static final int SCORE = 0;
	public static final int CASE_ID = 1;
	public static final int INDUSTRY = 2;
	public static final int PROBLEM_TYPE = 3;
	public static final int BUSINESS_OBJECTIVE = 4;
	public static final int DATAMINING_GOAL = 5;
	public static final int COMPANY_NAME = 6;

	/**
	 * Sorting criteria currently used
	 */
	private int m_SortBy;

	/**
	 * Current sorting order
	 */
	private boolean m_Ascending;

	/**
	 * Constructs a CaseInformationComparator
	 */
	public CaseInformationComparator() {
		super();
		setSortBy(SCORE);
		setAscending(false);
	}

	/**
	 * Gets the sorting criteria used.
	 * @return the sorting criteria used.
	 */
	public int getSortBy() {
		return m_SortBy;
	}

	/**
	 * Sets the sorting criteria used.
	 * @param a_SortBy the sorting criteria to be set.
	 */
	public void setSortBy(int a_SortBy) {
		m_SortBy = a_SortBy;
	}

	/**
	 * Gets the sorting order used.
	 * @return true if the current sorting order is ascending; false otherwise.
	 */
	public boolean getAscending() {
		return m_Ascending;
	}

	/**
	 * Sets the sorting order.
	 * @param a_IsAscending set the sorting order used.
	 */
	public void setAscending(boolean a_IsAscending) {
		m_Ascending = a_IsAscending;
	}

	/**
	 * @see java.util.Comparator#compare(Object, Object)
	 */
	public int compare(Object a_Obj1, Object a_Obj2) {
		CaseInformation info1 = (CaseInformation) a_Obj1;
		CaseInformation info2 = (CaseInformation) a_Obj2;

		int sortBy = getSortBy();
		if (sortBy == SCORE)
			return compareNumber(info1.getScore(), info2.getScore());
		else if (sortBy == CASE_ID)
			return compareString(info1.getCaseID(), info2.getCaseID());
		else if (sortBy == INDUSTRY)
			return compareString(info1.getIndustry(), info2.getIndustry());
		else if (sortBy == PROBLEM_TYPE)
			return compareString(
				info1.getProblemType(),
				info2.getProblemType());
		else if (sortBy == BUSINESS_OBJECTIVE)
			return compareString(
				info1.getBusinessObjective(),
				info2.getBusinessObjective());
		else if (sortBy == DATAMINING_GOAL)
			return compareString(
				info1.getDataMiningGoal(),
				info2.getDataMiningGoal());
		else if (sortBy == COMPANY_NAME)
			return compareString(
				info1.getCompanyName(),
				info2.getCompanyName());
		else
			return 1;
	}

	/**
	 * Compares values of two numbers for sorting them in ascending or 
	 * decending order.
	 * @param a_Num1 one of the two numbers to be compared.
	 * @param a_Num2 one of the two numbers to be copmared.
	 * @return if numbers are to be sort in ascending order,
	 * return 1 if a_Num1 is greater than a_Num2,
	 * return 0 if they are equal or return -1 if a_Num1 is smaller than a_Num2;
	 * otherwise, return 1 if a_Num1 is smaller than a_Num2,
	 * return 0 if they are equal or return -1 if a_Num1 is greater than a_Num2.
	 */
	private int compareNumber(double a_Num1, double a_Num2) {
		if (getAscending()) {
			if (a_Num1 > a_Num2)
				return 1;
			else if (a_Num1 == a_Num2)
				return 0;
			else
				return -1;
		} else {
			if (a_Num1 < a_Num2)
				return 1;
			else if (a_Num1 == a_Num2)
				return 0;
			else
				return -1;
		}
	}

	/**
	 * Compares values of two strings for sorting them in ascending or
	 * decending order.
	 * @param a_String1 one of the two strings to be compared.
	 * @param a_String2 one of the two strings to be compared.
	 * @return if strings are to be sort in ascending order,
	 * return 1 if a_String1 is greater than a_String2,
	 * return 0 if they are equal or return -1 if a_String1 is smaller than a_String2;
	 * otherwise, return 1 if a_String1 is smaller than a_String2,
	 * return 0 if they are equal or return -1 if a_String1 is greater than a_String2.
	 */
	private int compareString(String a_String1, String a_String2) {
		int result = a_String1.compareToIgnoreCase(a_String2);
		if (getAscending()) {
			if (result > 0)
				return 1;
			else if (result == 0)
				return 0;
			else
				return -1;
		} else {
			if (result < 0)
				return 1;
			else if (result == 0)
				return 0;
			else
				return -1;
		}
	}
}