/*******************************************************************************
 * Copyright (C) 2026, Leo Galambos
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 *    This product includes software developed by the Egothor project.
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package zeroecho.core;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import conflux.CtxInterface;

/**
 * Optional SPI to write/read a small header that carries runtime params (e.g.,
 * IV, tag length, AAD hash). If used, encryption will prepend the header and
 * decryption will parse it before initializing the cipher.
 */
public interface SymmetricHeaderCodec {
    /** Write header to {@code out}, using/recording params from {@code ctx}. */
    void writeHeader(OutputStream out, CryptoAlgorithm algorithm, CtxInterface ctx) throws IOException;

    /**
     * Read header from {@code in}, populate params in {@code ctx}, and return an
     * InputStream positioned immediately after the header.
     */
    InputStream readHeader(InputStream in, CryptoAlgorithm algorithm, CtxInterface ctx) throws IOException;
}
