/*
 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.jmx.snmp.agent;

import java.util.Enumeration;
import java.util.Vector;


import com.sun.jmx.snmp.SnmpPdu;
import com.sun.jmx.snmp.SnmpVarBind;
import com.sun.jmx.snmp.SnmpEngine;

/**
 * This class implements the SnmpMibRequest interface.
 * It represents the part of a SNMP request that involves a specific
 * MIB. One instance of this class will be created for every MIB
 * involved in a SNMP request, and will be passed to the SnmpMibAgent
 * in charge of handling that MIB.
 *
 * Instances of this class are allocated by the SNMP engine. You will
 * never need to use this class directly. You will only access
 * instances of this class through their SnmpMibRequest interface.
 *
 */
final class SnmpMibRequestImpl implements SnmpMibRequest {

    /**
     * @param engine The local engine.
     * @param reqPdu The received pdu.
     * @param vblist The vector of SnmpVarBind objects in which the
     *        MIB concerned by this request is involved.
     * @param protocolVersion  The protocol version of the SNMP request.
     * @param userData     User allocated contextual data. This object must
     *        be allocated on a per SNMP request basis through the
     *        SnmpUserDataFactory registered with the SnmpAdaptorServer,
     *        and is handed back to the user through SnmpMibRequest objects.
     */
    public SnmpMibRequestImpl(SnmpEngine engine,
                              SnmpPdu reqPdu,
                              Vector<SnmpVarBind> vblist,
                              int protocolVersion,
                              Object userData,
                              String principal,
                              int securityLevel,
                              int securityModel,
                              byte[] contextName,
                              byte[] accessContextName) {
        varbinds   = vblist;
        version    = protocolVersion;
        data       = userData;
        this.reqPdu = reqPdu;
        this.engine = engine;
        this.principal = principal;
        this.securityLevel = securityLevel;
        this.securityModel = securityModel;
        this.contextName = contextName;
        this.accessContextName = accessContextName;
    }
    // -------------------------------------------------------------------
    // PUBLIC METHODS from SnmpMibRequest
    // -------------------------------------------------------------------

    /**
     * Returns the local engine. This parameter is returned only if <CODE> SnmpV3AdaptorServer </CODE> is the adaptor receiving this request. Otherwise null is returned.
     * @return the local engine.
     */
    @Override
    public SnmpEngine getEngine() {
        return engine;
    }

    /**
     * Gets the incoming request principal. This parameter is returned only if <CODE> SnmpV3AdaptorServer </CODE> is the adaptor receiving this request. Otherwise null is returned.
     * @return The request principal.
     **/
    @Override
    public String getPrincipal() {
        return principal;
    }

    /**
     * Gets the incoming request security level. This level is defined in {@link com.sun.jmx.snmp.SnmpEngine SnmpEngine}. This parameter is returned only if <CODE> SnmpV3AdaptorServer </CODE> is the adaptor receiving this request. Otherwise -1 is returned.
     * @return The security level.
     */
    @Override
    public int getSecurityLevel() {
        return securityLevel;
    }
    /**
     * Gets the incoming request security model. This parameter is returned only if <CODE> SnmpV3AdaptorServer </CODE> is the adaptor receiving this request. Otherwise -1 is returned.
     * @return The security model.
     */
    @Override
    public int getSecurityModel() {
        return securityModel;
    }
    /**
     * Gets the incoming request context name. This parameter is returned only if <CODE> SnmpV3AdaptorServer </CODE> is the adaptor receiving this request. Otherwise null is returned.
     * @return The context name.
     */
    @Override
    public byte[] getContextName() {
        return contextName;
    }

    /**
     * Gets the incoming request context name used by Access Control Model in order to allow or deny the access to OIDs. This parameter is returned only if <CODE> SnmpV3AdaptorServer </CODE> is the adaptor receiving this request. Otherwise null is returned.
     * @return The checked context.
     */
    @Override
    public byte[] getAccessContextName() {
        return accessContextName;
    }

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final SnmpPdu getPdu() {
        return reqPdu;
    }

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final Enumeration<SnmpVarBind> getElements()  {return varbinds.elements();}

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final Vector<SnmpVarBind> getSubList()  {return varbinds;}

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final int getSize()  {
        if (varbinds == null) return 0;
        return varbinds.size();
    }

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final int         getVersion()  {return version;}

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final int         getRequestPduVersion()  {return reqPdu.version;}

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final Object      getUserData() {return data;}

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public final int getVarIndex(SnmpVarBind varbind) {
        return varbinds.indexOf(varbind);
    }

    // -------------------------------------------------------------------
    // Implements the method defined in SnmpMibRequest interface.
    // See SnmpMibRequest for the java doc.
    // -------------------------------------------------------------------
    @Override
    public void addVarBind(SnmpVarBind varbind) {
        varbinds.addElement(varbind);
    }

    // -------------------------------------------------------------------
    // PACKAGE METHODS
    // -------------------------------------------------------------------

    // -------------------------------------------------------------------
    // Allow to pass the request tree built during the check() phase
    // to the set() method. Note: the if the tree is `null', then the
    // set() method will rebuild a new tree identical to the tree built
    // in the check() method.
    //
    // Passing this tree in the SnmpMibRequestImpl object allows to
    // optimize the SET requests.
    //
    // -------------------------------------------------------------------
    final void setRequestTree(SnmpRequestTree tree) {this.tree = tree;}

    // -------------------------------------------------------------------
    // Returns the SnmpRequestTree object built in the first operation
    // phase for two-phase SNMP requests (like SET).
    // -------------------------------------------------------------------
    final SnmpRequestTree getRequestTree() {return tree;}

    // -------------------------------------------------------------------
    // Returns the underlying vector of SNMP varbinds (used for algorithm
    // optimization).
    // -------------------------------------------------------------------
    final Vector<SnmpVarBind> getVarbinds() {return varbinds;}

    // -------------------------------------------------------------------
    // Private variables
    // -------------------------------------------------------------------

    // Ideally these variables should be declared final but it makes
    // the jdk1.1.x compiler complain (seems to be a compiler bug, jdk1.2
    // is OK).
    private Vector<SnmpVarBind> varbinds;
    private int    version;
    private Object data;
    private SnmpPdu reqPdu = null;
    // Non final variable.
    private SnmpRequestTree tree = null;
    private SnmpEngine engine = null;
    private String principal = null;
    private int securityLevel = -1;
    private int securityModel = -1;
    private byte[] contextName = null;
    private byte[] accessContextName = null;
}