/*
 * Copyright 2005-2010 the original author or authors.
 * 
 * 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.
 */ 
package org.wamblee.security.authorization;

import javax.persistence.Access;
import javax.persistence.AccessType;
import javax.persistence.Column;
import javax.persistence.DiscriminatorValue;
import javax.persistence.Entity;

/**
 * Determiens if an operation is a subclass of a specified operation.
 */
@Entity
@DiscriminatorValue("ISA")
@Access(AccessType.PROPERTY)
public class IsaOperationCondition extends AbstractOperationCondition {
    /**
     * Operation that the other operation must be a subclass of.
     */
    private Class<? extends Operation> operation;

    /**
     * Constructs the condition.
     * 
     * @param aOperation
     *            Operation that an operation must be an instance of.
     */
    public IsaOperationCondition(Class<? extends Operation> aOperation) {
        operation = aOperation;
    }

    /**
     * For OR mapping.
     * 
     */
    public IsaOperationCondition() {
        operation = null;
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.wamblee.security.authorization.OperationCondition#matches(org.wamblee
     * .security.authorization.Operation)
     */
    public boolean matches(Operation aOperation) {
        return operation.isInstance(aOperation);
    }

    /**
     * Gets the operation as a string. For OR mapping only.
     * 
     * @return Operation string.
     */
    @Column(name = "CLASSNAME")
    protected String getOperationString() {
        if (operation == null) {
            return null;
        }

        return operation.getName();
    }

    /**
     * Sets the operation as a string. For OR mapping only.
     * 
     * @param aOperation
     *            Operation string.
     * 
     */
    protected void setOperationString(String aOperation) {
        if (aOperation == null) {
            return;
        }

        try {
            operation = (Class<? extends Operation>) Class.forName(aOperation);
        } catch (Exception e) {
            throw new IllegalArgumentException("Unknown class '" + aOperation +
                "'");
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return "IsaOperationCondition(operation=" + operation.getName() + ")";
    }
}