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 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
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 *  KIND, either express or implied.  See the License for the
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package org.apache.cayenne.crypto.transformer.value;

import org.apache.cayenne.crypto.transformer.bytes.BytesEncryptor;

/**
 * @since 4.0
 */
class DefaultValueEncryptor implements ValueEncryptor {

    private BytesConverter preConverter;
    private BytesConverter postConverter;

    public DefaultValueEncryptor(BytesConverter preConverter, BytesConverter postConverter) {
        this.preConverter = preConverter;
        this.postConverter = postConverter;
    }

    BytesConverter getPreConverter() {
        return preConverter;
    }

    BytesConverter getPostConverter() {
        return postConverter;
    }

    @Override
    public Object encrypt(BytesEncryptor encryptor, Object value) {

        // TODO: should we encrypt nulls as well to hide NULL from attackers?
        if (value == null) {
            return null;
        }

        @SuppressWarnings("unchecked")
        byte[] bytes = preConverter.toBytes(value);
        byte[] transformed = encryptor.encrypt(bytes, 0, new byte[1]);
        return postConverter.fromBytes(transformed);
    }

}