/*

 * Copyright (c) 1997, 2015, 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

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 * questions.

 */

package sun.security.x509;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.Enumeration;

import sun.security.util.*;

/**

 * Represent the CRL Reason Flags.

 *

 * <p>This extension, if present, defines the identifies

 * the reason for the certificate revocation.

 * <p>The ASN.1 syntax for this is:

 * <pre>

 * ReasonFlags ::= BIT STRING {

 *    unused                  (0),

 *    keyCompromise           (1),

 *    cACompromise            (2),

 *    affiliationChanged      (3),

 *    superseded              (4),

 *    cessationOfOperation    (5),

 *    certificateHold         (6),

 *    privilegeWithdrawn      (7),

 *    aACompromise            (8) }

 * </pre>

 *

 * @author Hemma Prafullchandra

 */

public class ReasonFlags {

    /**

     * Reasons

     */

    public static final String UNUSED = "unused";

    public static final String KEY_COMPROMISE = "key_compromise";

    public static final String CA_COMPROMISE = "ca_compromise";

    public static final String AFFILIATION_CHANGED = "affiliation_changed";

    public static final String SUPERSEDED = "superseded";

    public static final String CESSATION_OF_OPERATION

                                   = "cessation_of_operation";

    public static final String CERTIFICATE_HOLD = "certificate_hold";

    public static final String PRIVILEGE_WITHDRAWN = "privilege_withdrawn";

    public static final String AA_COMPROMISE = "aa_compromise";

    private static final String[] NAMES = {

        UNUSED,

        KEY_COMPROMISE,

        CA_COMPROMISE,

        AFFILIATION_CHANGED,

        SUPERSEDED,

        CESSATION_OF_OPERATION,

        CERTIFICATE_HOLD,

        PRIVILEGE_WITHDRAWN,

        AA_COMPROMISE,

    };

    private static int name2Index(String name) throws IOException {

        for( int i=0; i<NAMES.length; i++ ) {

            if( NAMES[i].equalsIgnoreCase(name) ) {

                return i;

            }

        }

        throw new IOException("Name not recognized by ReasonFlags");

    }

    // Private data members

    private boolean[] bitString;

    /**

     * Check if bit is set.

     *

     * @param position the position in the bit string to check.

     */

    private boolean isSet(int position) {

        return (position < bitString.length) &&

                bitString[position];

    }

    /**

     * Set the bit at the specified position.

     */

    private void set(int position, boolean val) {

        // enlarge bitString if necessary

        if (position >= bitString.length) {

            boolean[] tmp = new boolean[position+1];

            System.arraycopy(bitString, 0, tmp, 0, bitString.length);

            bitString = tmp;

        }

        bitString[position] = val;

    }

    /**

     * Create a ReasonFlags with the passed bit settings.

     *

     * @param reasons the bits to be set for the ReasonFlags.

     */

    public ReasonFlags(byte[] reasons) {

        bitString = new BitArray(reasons.length*8, reasons).toBooleanArray();

    }

    /**

     * Create a ReasonFlags with the passed bit settings.

     *

     * @param reasons the bits to be set for the ReasonFlags.

     */

    public ReasonFlags(boolean[] reasons) {

        this.bitString = reasons;

    }

    /**

     * Create a ReasonFlags with the passed bit settings.

     *

     * @param reasons the bits to be set for the ReasonFlags.

     */

    public ReasonFlags(BitArray reasons) {

        this.bitString = reasons.toBooleanArray();

    }

    /**

     * Create the object from the passed DER encoded value.

     *

     * @param in the DerInputStream to read the ReasonFlags from.

     * @exception IOException on decoding errors.

     */

    public ReasonFlags(DerInputStream in) throws IOException {

        DerValue derVal = in.getDerValue();

        this.bitString = derVal.getUnalignedBitString(true).toBooleanArray();

    }

    /**

     * Create the object from the passed DER encoded value.

     *

     * @param derVal the DerValue decoded from the stream.

     * @exception IOException on decoding errors.

     */

    public ReasonFlags(DerValue derVal) throws IOException {

        this.bitString = derVal.getUnalignedBitString(true).toBooleanArray();

    }

    /**

     * Returns the reason flags as a boolean array.

     */

    public boolean[] getFlags() {

        return bitString;

    }

    /**

     * Set the attribute value.

     */

    public void set(String name, Object obj) throws IOException {

        if (!(obj instanceof Boolean)) {

            throw new IOException("Attribute must be of type Boolean.");

        }

        boolean val = ((Boolean)obj).booleanValue();

        set(name2Index(name), val);

    }

    /**

     * Get the attribute value.

     */

    public Object get(String name) throws IOException {

        return Boolean.valueOf(isSet(name2Index(name)));

    }

    /**

     * Delete the attribute value.

     */

    public void delete(String name) throws IOException {

        set(name, Boolean.FALSE);

    }

    /**

     * Returns a printable representation of the ReasonFlags.

     */

    public String toString() {

        StringBuilder sb = new StringBuilder("Reason Flags [\n");

        if (isSet(0)) {

            sb.append("  Unused\n");

        }

        if (isSet(1)) {

            sb.append("  Key Compromise\n");

        }

        if (isSet(2)) {

            sb.append("  CA Compromise\n");

        }

        if (isSet(3)) {

            sb.append("  Affiliation_Changed\n");

        }

        if (isSet(4)) {

            sb.append("  Superseded\n");

        }

        if (isSet(5)) {

            sb.append("  Cessation Of Operation\n");

        }

        if (isSet(6)) {

            sb.append("  Certificate Hold\n");

        }

        if (isSet(7)) {

            sb.append("  Privilege Withdrawn\n");

        }

        if (isSet(8)) {

            sb.append("  AA Compromise\n");

        }

        sb.append("]\n");

        return sb.toString();

    }

    /**

     * Write the extension to the DerOutputStream.

     *

     * @param out the DerOutputStream to write the extension to.

     * @exception IOException on encoding errors.

     */

    public void encode(DerOutputStream out) throws IOException {

        out.putTruncatedUnalignedBitString(new BitArray(this.bitString));

    }

    /**

     * Return an enumeration of names of attributes existing within this

     * attribute.

     */

    public Enumeration<String> getElements () {

        AttributeNameEnumeration elements = new AttributeNameEnumeration();

        for( int i=0; i<NAMES.length; i++ ) {

            elements.addElement(NAMES[i]);

        }

        return (elements.elements());

    }

}