/*
 * The contents of this file are subject to the terms of the Common Development and
 * Distribution License (the License). You may not use this file except in compliance with the
 * License.
 *
 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
 * specific language governing permission and limitations under the License.
 *
 * When distributing Covered Software, include this CDDL Header Notice in each file and include
 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2008 Sun Microsystems, Inc.
 */

package org.opends.server.authorization.dseecompat;

/**
 * This class provides an enumeration of evaluation results returned by
 * the bind rule evaluation methods.
 */
public enum EnumEvalResult {

    /**
     * This enumeration is returned when the result of the evaluation is TRUE.
     */
    TRUE(0),
    /**
     * This enumeration is returned when the result of the evaluation is FALSE.
     */
    FALSE(1),
    /**
     * This enumeration is returned when the result of the evaluation is FAIL.
     * This should only be returned when a system failure occurred.
     */
    FAIL(2),
    /**
     * This is an internal enumeration used during evaluation of bind rule when
     * internal processing of the evaluation is undefined. It is never returned
     * back as a result of the evaluation.
     */
    ERR(3);

    /**
     * Create a new enumeration type for the specified result value.
     * @param v The value of the result.
     */
    EnumEvalResult(int v) {
    }

    /**
     * The method tries to determine if the result was undefined, and if so
     * it returns an FAIL enumeration. If the result was not undefined (the
     * common case for all of the bind rule evaluations), then the bind rule
     * type is examined to see if the result needs to be flipped (type equals
     * NOT_EQUAL_BINDRULE_TYPE).
     * @param type The bind rule type enumeration of the bind rule.
     * @param undefined  A flag that signals the the result was undefined.
     * @return An enumeration containing the correct result after processing
     * the undefined field and the bind rule type enumeration.
     */
    public EnumEvalResult getRet(EnumBindRuleType type, boolean undefined) {
        if (equals(EnumEvalResult.TRUE) || !undefined) {
            if (EnumBindRuleType.NOT_EQUAL_BINDRULE_TYPE.equals(type)) {
              return negate(this);
            }
        } else {
            return EnumEvalResult.FAIL;
        }
        return this;
    }

    /**
     * This method is used to possibly negate the result of a simple bind rule
     * evaluation. If the boolean is true than the result is negated.
     * @param v The enumeration result of the simple bind rule evaluation.
     * @param negate If true the result should be negated (TRUE->FALSE, FALSE->TRUE).
     * @return  A possibly negated enumeration result.
     */
    public  static EnumEvalResult negateIfNeeded(EnumEvalResult v, boolean negate) {
        if (negate) {
            return negate(v);
        }
        return v;
    }

    private static EnumEvalResult negate(EnumEvalResult v) {
        if (EnumEvalResult.TRUE.equals(v)) {
            return EnumEvalResult.FALSE;
        } else {
            return EnumEvalResult.TRUE;
        }
    }

    /**
     * Helper method that converts this enumeration to a boolean. Usually the
     * FAIL enumeration has been handled before this is called.
     * @return True if the enumeration is TRUE, else false.
     */
    public boolean getBoolVal() {
        return this == EnumEvalResult.TRUE;
    }
}