#include <iostream>
#include <string>

#include "cryptlib.h"
#include "filters.h"
#include "files.h"
#include "sha.h"
#include "hex.h"

int main(int argc, char* argv[])
{
    using namespace CryptoPP;

    // Create a file of all 0's with:
    // dd if=/dev/zero of=./zero.dat bs=4096 count=1

    std::string digest;
    SHA256 sha256;

    // Create the digest on the file
    FileSource("zero.dat", true, new HashFilter(sha256, new StringSink(digest)));

    // Print the digest
    std::cout << "Digest: ";
    StringSource(digest, true, new HexEncoder(new FileSink(std::cout)));
    std::cout << std::endl;

	// Create a verifier
    byte result = 0;
    HashVerificationFilter verifier(sha256, new ArraySink(&result, sizeof(result)));

	// Wrap the data in sources
	StringSource ss(digest, true);
    FileSource fs("zero.dat", true);

	// Add the data to the filter
    ss.TransferTo(verifier);
    fs.TransferTo(verifier);

	// Signal end of data. The verifier will finish calculating
	// the digest, and compare the expected and calculated digests.
    verifier.MessageEnd();

    if (result)
        std::cout << "Verified hash on file" << std::endl;
    else
        std::cout << "Failed to verify hash on file" << std::endl;

    return 0;
}