#ifndef PL_SHA2_HH

#define PL_SHA2_HH

#include <qpdf/Pipeline.hh>

#include <qpdf/QPDFCryptoImpl.hh>

#include <memory>

// Bits must be a supported number of bits, currently only 256, 384, or 512.  Passing 0 as bits

// leaves the pipeline uncommitted, in which case resetBits must be called before the pipeline is

// used. If a next is provided, this pipeline sends its output to its successor unmodified.  After

// calling finish, the SHA2 checksum of the data that passed through the pipeline is available.

//

// This pipeline is reusable; i.e., it is safe to call write() after calling finish().  The first

// call to write() after a call to finish() initializes a new SHA2 object.  resetBits may also be

// called between finish and the next call to write.

class Pl_SHA2 final: public Pipeline

{

  public:

    Pl_SHA2(int bits = 0, Pipeline* next = nullptr);

    ~Pl_SHA2() final = default;

    void write(unsigned char const*, size_t) final;

    void finish() final;

    void resetBits(int bits);

    std::string getHexDigest();

    std::string getRawDigest();

  private:

    bool in_progress{false};

    std::shared_ptr<QPDFCryptoImpl> crypto;

};

#endif // PL_SHA2_HH