/*
 * Copyright (C) 2008 Esmertec AG.
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.im.imps;

import com.android.im.engine.ImException;

import org.apache.commons.codec.binary.Base64;

import android.security.MessageDigest;

import java.io.UnsupportedEncodingException;
import java.security.NoSuchAlgorithmException;

public class StandardPasswordDigest implements PasswordDigest {

    public String digest(String schema, String nonce, String password) throws ImException {
        byte[] digestBytes;
        byte[] inputBytes;

        try {
            inputBytes = (nonce + password).getBytes("ISO-8859-1");
        } catch (UnsupportedEncodingException e) {
            throw new ImException(e);
        }

        try {
            if ("SHA".equals(schema))
                schema = "SHA-1";
            MessageDigest md = MessageDigest.getInstance(schema);
            digestBytes = md.digest(inputBytes);
        } catch (NoSuchAlgorithmException e) {
            throw new ImException("Unsupported schema: " + schema);
        }
        return new String(Base64.encodeBase64(digestBytes));
    }

    public String[] getSupportedDigestSchema() {
        return new String[] {"MD5", "SHA"};
    }

}