/*
 * Copyright (c) 2012-2016 Arne Schwabe
 * Distributed under the GNU GPL v2 with additional terms. For full terms see the file doc/LICENSE.txt
 */

package org.spongycastle.util.encoders;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;

public class Base64 {
    private static final Encoder encoder = new Base64Encoder();

    /**
     * encode the input data producing a base 64 encoded byte array.
     *
     * @return a byte array containing the base 64 encoded data.
     */
    public static byte[] encode(byte[] data) {
        int len = (data.length + 2) / 3 * 4;
        ByteArrayOutputStream bOut = new ByteArrayOutputStream(len);

        try {
            encoder.encode(data, 0, data.length, bOut);
        } catch (IOException e) {
            throw new RuntimeException("exception encoding base64 string: " + e);
        }

        return bOut.toByteArray();
    }

    /**
     * Encode the byte data to base 64 writing it to the given output stream.
     *
     * @return the number of bytes produced.
     */
    public static int encode(byte[] data, OutputStream out) throws IOException {
        return encoder.encode(data, 0, data.length, out);
    }

    /**
     * Encode the byte data to base 64 writing it to the given output stream.
     *
     * @return the number of bytes produced.
     */
    public static int encode(byte[] data, int off, int length, OutputStream out) throws IOException {
        return encoder.encode(data, off, length, out);
    }

    /**
     * decode the base 64 encoded input data. It is assumed the input data is valid.
     *
     * @return a byte array representing the decoded data.
     */
    public static byte[] decode(byte[] data) {
        int len = data.length / 4 * 3;
        ByteArrayOutputStream bOut = new ByteArrayOutputStream(len);

        try {
            encoder.decode(data, 0, data.length, bOut);
        } catch (IOException e) {
            throw new RuntimeException("exception decoding base64 string: " + e);
        }

        return bOut.toByteArray();
    }

    /**
     * decode the base 64 encoded String data - whitespace will be ignored.
     *
     * @return a byte array representing the decoded data.
     */
    public static byte[] decode(String data) {
        int len = data.length() / 4 * 3;
        ByteArrayOutputStream bOut = new ByteArrayOutputStream(len);

        try {
            encoder.decode(data, bOut);
        } catch (IOException e) {
            throw new RuntimeException("exception decoding base64 string: " + e);
        }

        return bOut.toByteArray();
    }

    /**
     * decode the base 64 encoded String data writing it to the given output stream,
     * whitespace characters will be ignored.
     *
     * @return the number of bytes produced.
     */
    public static int decode(String data, OutputStream out) throws IOException {
        return encoder.decode(data, out);
    }
}