#include <qpdf/Pl_RC4.hh>

#include <qpdf/QUtil.hh>

Pl_RC4::Pl_RC4(

    char const* identifier,

    Pipeline* next,

    unsigned char const* key_data,

    int key_len,

    size_t out_bufsize) :

    Pipeline(identifier, next),

    out_bufsize(out_bufsize),

    rc4(key_data, key_len)

{

    if (!next) {

        throw std::logic_error("Attempt to create Pl_RC4 with nullptr as next");

    }

    this->outbuf = QUtil::make_shared_array<unsigned char>(out_bufsize);

}

void

Pl_RC4::write(unsigned char const* data, size_t len)

{

    if (this->outbuf == nullptr) {

        throw std::logic_error(this->identifier + ": Pl_RC4: write() called after finish() called");

    }

    size_t bytes_left = len;

    unsigned char const* p = data;

    while (bytes_left > 0) {

        size_t bytes = (bytes_left < this->out_bufsize ? bytes_left : out_bufsize);

        bytes_left -= bytes;

        // lgtm[cpp/weak-cryptographic-algorithm]

        rc4.process(p, bytes, outbuf.get());

        p += bytes;

        next()->write(outbuf.get(), bytes);

    }

}

void

Pl_RC4::finish()

{

    outbuf = nullptr;

    next()->finish();

}