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 * Copyright (c) 2012-2015, Vladimir Kravets                                  *
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package org.fidonet.binkp.common.commands;

import org.fidonet.binkp.common.SessionContext;

import java.security.MessageDigest;

/**
 * Created by IntelliJ IDEA.
 * Author: Vladimir Kravets
 * E-Mail: vova.kravets@gmail.com
 * Date: 9/23/12
 * Time: 5:04 PM
 */
public class CramOPTCommand extends OPTCommand {

    private MessageDigest messageDigest;

    public CramOPTCommand(MessageDigest messageDigest) {
        this.messageDigest = messageDigest;
        messageDigest.reset();
        messageDigest.update(String.format("%d%d", System.currentTimeMillis(),
                System.nanoTime()).getBytes());

    }

    @Override
    protected String getArguments(SessionContext sessionContext) {
        if (!sessionContext.getLinksInfo().getCurLink().isMD()) {
            return null;
        }
        final byte[] bufKey = messageDigest.digest();
        final StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 16; i++) {
            builder.append(String.format("%02x", bufKey[i]));
        }
        final String key = builder.toString();
        sessionContext.setPasswordKey(key);
        return String.format("CRAM-%s-%s", messageDigest.getAlgorithm(), key);
    }
}
