/*
 *  SSHTools - Java SSH2 API
 *
 *  Copyright (C) 2002-2003 Lee David Painter and Contributors.
 *
 *  Contributions made by:
 *
 *  Brett Smith
 *  Richard Pernavas
 *  Erwin Bolwidt
 *
 *  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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package com.sshtools.j2ssh.agent;

import com.sshtools.j2ssh.io.ByteArrayReader;
import com.sshtools.j2ssh.io.ByteArrayWriter;
import com.sshtools.j2ssh.io.UnsignedInteger32;

import java.io.IOException;


/**
 *
 *
 * @author $author$
 * @version $Revision: 1.12 $
 */
public class KeyConstraints {
    /**  */
    public static final long NO_TIMEOUT = 0;

    /**  */
    public static final long NO_LIMIT = 0xffffffffL;

    /**  */
    protected static final int SSH_AGENT_CONSTRAINT_TIMEOUT = 50;

    /**  */
    protected static final int SSH_AGENT_CONSTRAINT_USE_LIMIT = 51;

    /**  */
    protected static final int SSH_AGENT_CONSTRAINT_FORWARDING_STEPS = 52;

    /**  */
    protected static final int SSH_AGENT_CONSTRAINT_FORWARDING_PATH = 100;

    /**  */
    protected static final int SSH_AGENT_CONSTRAINT_SSH1_COMPAT = 150;

    /**  */
    protected static final int SSH_AGENT_CONSTRAINT_NEED_USER_VERIFICATION = 151;
    private UnsignedInteger32 timeout = new UnsignedInteger32(NO_TIMEOUT);
    private UnsignedInteger32 uselimit = new UnsignedInteger32(NO_LIMIT);
    private UnsignedInteger32 maxsteps = new UnsignedInteger32(NO_LIMIT);
    private String forwardingpath = "";
    private boolean userverify = false;
    private boolean compat = false;
    private long keyadded = System.currentTimeMillis();
    private long usedcount = 0;

    /**
     * Creates a new KeyConstraints object.
     */
    public KeyConstraints() {
    }

    /**
     * Creates a new KeyConstraints object.
     *
     * @param bar
     *
     * @throws IOException
     */
    public KeyConstraints(ByteArrayReader bar) throws IOException {
        while (bar.available() > 0) {
            switch (bar.read() & 0xFF) {
            case SSH_AGENT_CONSTRAINT_TIMEOUT:
                timeout = bar.readUINT32();

                break;

            case SSH_AGENT_CONSTRAINT_USE_LIMIT:
                uselimit = bar.readUINT32();

                break;

            case SSH_AGENT_CONSTRAINT_FORWARDING_STEPS:
                maxsteps = bar.readUINT32();

                break;

            case SSH_AGENT_CONSTRAINT_FORWARDING_PATH:
                forwardingpath = bar.readString();

                break;

            case SSH_AGENT_CONSTRAINT_SSH1_COMPAT:
                compat = (bar.read() != 0);

                break;

            case SSH_AGENT_CONSTRAINT_NEED_USER_VERIFICATION:
                userverify = (bar.read() != 0);

                break;
            }
        }
    }

    /**
     *
     *
     * @param timeout
     */
    public void setKeyTimeout(UnsignedInteger32 timeout) {
        this.timeout = timeout;
    }

    /**
     *
     *
     * @param uselimit
     */
    public void setKeyUseLimit(int uselimit) {
        this.uselimit = new UnsignedInteger32(uselimit);
    }

    /**
     *
     *
     * @param maxsteps
     */
    public void setMaximumForwardingSteps(int maxsteps) {
        this.maxsteps = new UnsignedInteger32(maxsteps);
    }

    /**
     *
     *
     * @param forwardingpath
     */
    public void setForwardingPath(String forwardingpath) {
        this.forwardingpath = forwardingpath;
    }

    /**
     *
     *
     * @param userverify
     */
    public void setRequiresUserVerification(boolean userverify) {
        this.userverify = userverify;
    }

    /**
     *
     *
     * @param compat
     */
    public void setSSH1Compatible(boolean compat) {
        this.compat = compat;
    }

    /**
     *
     *
     * @return
     */
    public long getKeyTimeout() {
        return timeout.longValue();
    }

    /**
     *
     *
     * @return
     */
    public long getKeyUseLimit() {
        return uselimit.longValue();
    }

    /**
     *
     *
     * @return
     */
    public long getMaximumForwardingSteps() {
        return maxsteps.longValue();
    }

    /**
     *
     *
     * @return
     */
    public long getUsedCount() {
        return usedcount;
    }

    /**
     *
     *
     * @return
     */
    public boolean hasTimedOut() {
        return (timeout.longValue() != 0)
        ? (((System.currentTimeMillis() - keyadded) / 1000) > timeout.longValue())
        : false;
    }

    /**
     *
     *
     * @return
     */
    public boolean canUse() {
        return (uselimit.longValue() != 0) ? (usedcount < uselimit.longValue())
                                           : true;
    }

    /**
     *
     */
    public void use() {
        usedcount++;
    }

    /**
     *
     *
     * @return
     */
    public String getForwardingPath() {
        return forwardingpath;
    }

    /**
     *
     *
     * @return
     */
    public boolean requiresUserVerification() {
        return userverify;
    }

    /**
     *
     *
     * @return
     */
    public boolean isSSH1Compatible() {
        return compat;
    }

    /**
     *
     *
     * @return
     *
     * @throws IOException
     */
    public byte[] toByteArray() throws IOException {
        ByteArrayWriter baw = new ByteArrayWriter();
        baw.write(SSH_AGENT_CONSTRAINT_TIMEOUT);
        baw.writeUINT32(timeout);
        baw.write(SSH_AGENT_CONSTRAINT_USE_LIMIT);
        baw.writeUINT32(uselimit);
        baw.write(SSH_AGENT_CONSTRAINT_FORWARDING_STEPS);
        baw.writeUINT32(maxsteps);
        baw.write(SSH_AGENT_CONSTRAINT_FORWARDING_PATH);
        baw.writeString(forwardingpath);
        baw.write(SSH_AGENT_CONSTRAINT_SSH1_COMPAT);
        baw.write(compat ? 0 : 1);
        baw.write(SSH_AGENT_CONSTRAINT_NEED_USER_VERIFICATION);
        baw.write(userverify ? 0 : 1);

        return baw.toByteArray();
    }
}
