/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you 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.
 *
 */

/*
 *                        AT&T - PROPRIETARY
 *          THIS FILE CONTAINS PROPRIETARY INFORMATION OF
 *        AT&T AND IS NOT TO BE DISCLOSED OR USED EXCEPT IN
 *             ACCORDANCE WITH APPLICABLE AGREEMENTS.
 *
 *          Copyright (c) 2013 AT&T Knowledge Ventures
 *              Unpublished and Not for Publication
 *                     All Rights Reserved
 */
package org.apache.openaz.xacml.pdp.policy;

import org.apache.openaz.xacml.api.StatusCode;
import org.apache.openaz.xacml.std.StdStatusCode;

/**
 * PolicyComponent is the base class for all pieces of a XACML Policy or PolicySet that could potentially have
 * errors associated with them by the policy loader.
 */
abstract class PolicyComponent {
    private StatusCode statusCode;
    private String statusMessage;

    /**
     * Creates a new <code>PolicyComponent</code> with the given {@link org.apache.openaz.xacml.api.StatusCode}
     * and <code>String</code> detailed message. If the <code>StatusCode</code> is null, a default OK status
     * code is used.
     *
     * @param statusCodeIn the <code>StatusCode</code> for the new <code>PolicyComponent</code>
     * @param statusMessageIn the <code>String</code> detailed status message for the new
     *            <code>PolicyComponent</code>
     */
    public PolicyComponent(StatusCode statusCodeIn, String statusMessageIn) {
        this.statusCode = statusCodeIn;
        this.statusMessage = statusMessageIn;
    }

    /**
     * Creates a new <code>PolicyComponent</code> with the given <code>StatusCode</code> and no status
     * message.
     *
     * @param statusCodeIn the <code>StatusCode</code> for the new <code>PolicyComponent</code>
     */
    public PolicyComponent(StatusCode statusCodeIn) {
        this(statusCodeIn, null);
    }

    /**
     * Creates a new <code>PolicyCOmponent</code> with no <code>StatusCode</code> or status message.
     */
    public PolicyComponent() {
        this(null, null);
    }

    /**
     * Gets the <code>StatusCode</code> associated with this <code>PolicyComponent</code>.
     *
     * @return the <code>StatusCode</code> associated with this <code>PolicyComponent</code>
     */
    public StatusCode getStatusCode() {
        return this.statusCode;
    }

    /**
     * Gets the <code>String</code> status message associated with this <code>PolicyComponent</code>.
     *
     * @return the <code>String</code> status message associated with this <code>PolicyComponent</code> or
     *         null if none
     */
    public String getStatusMessage() {
        return this.statusMessage;
    }

    /**
     * Sets the <code>StatusCode</code> and <code>String</code> status message for this
     * <code>PolicyComponent</code>. This method is mainly provided for objects that may have lazy evaluations
     * performed on them, in which case the status is not determined until the object is actually used.
     *
     * @param statusCodeIn the <code>StatusCode</code> for this <code>PolicyComponent</code>
     * @param messageIn the <code>String</code> status message for this <code>PolicyComponent</code>
     */
    public void setStatus(StatusCode statusCodeIn, String messageIn) {
        this.statusCode = statusCodeIn;
        this.statusMessage = messageIn;
    }

    /**
     * Does a check on the <code>StatusCode</code> for this element to determine if it is equivalent to the OK
     * status code.
     *
     * @return true if the <code>StatusCode</code> is equivalent to OK, otherwise false
     */
    public boolean isOk() {
        return StdStatusCode.STATUS_CODE_OK.equals(this.getStatusCode());
    }

    /**
     * Validates that this <code>PolicyComponent</code> has all of the required elements according to the
     * XACML 3.0 specification. If the component is not valid, this method should set the
     * <code>StatusCode</code> to reflect a syntax error, and should set the status message to reflect the
     * invalid piece(s). <code>PolicyComponent</code>s that implement this method should only validate their
     * immediate elements and not perform a deep validation of descendents.
     *
     * @return true if the resulting status code is OK, otherwise false
     */
    abstract protected boolean validateComponent();

    /**
     * If a <code>StatusCode</code> has not been set, ask this <code>PolicyComponent</code> to validate itself
     * and return the value from the validation. Otherwise, check to see if the cached <code>StatusCode</code>
     * indicates this <code>PolicyComponent</code> is valid.
     *
     * @return true if this <code>PolicyComponent</code> is valid, else false.
     */
    public boolean validate() {
        if (this.getStatusCode() == null) {
            return this.validateComponent();
        } else {
            return this.isOk();
        }
    }

    @Override
    public String toString() {
        StringBuilder stringBuilder = new StringBuilder("{");
        Object objectToDump;
        boolean needsComma = false;
        if ((objectToDump = this.getStatusCode()) != null) {
            stringBuilder.append("statusCode=");
            stringBuilder.append(objectToDump.toString());
            needsComma = true;
        }
        if ((objectToDump = this.getStatusMessage()) != null) {
            if (needsComma) {
                stringBuilder.append(',');
            }
            stringBuilder.append("statusMessage=");
            stringBuilder.append((String)objectToDump);
            needsComma = true;
        }
        stringBuilder.append('}');
        return stringBuilder.toString();
    }

}