using Invercargill;
namespace Pprf.Util {

    public static uint8[] string_checksum(string str) {
        return data_checksum(str.data);
    }

    public static uint8[] data_checksum(uint8[] data) {
        var checksum_calculator = new Checksum(ChecksumType.SHA512);
        checksum_calculator.update(data, data.length);

        var checksum = new uint8[ChecksumType.SHA512.get_length()];
        size_t chk_len = checksum.length;
        checksum_calculator.get_digest(checksum, ref chk_len);
        checksum.length = (int)chk_len;
        return checksum;
    }

    public static uint8[] file_checksum(File file) throws Error {
        var buffer = new uint8[10240];
        var checksum = new Checksum(ChecksumType.SHA512);
        var stream = file.read();
        while(true) {
            var read = stream.read(buffer);
            if(read == 0) {
                break;
            }
            checksum.update(buffer, read);
        }
        size_t dig_len = 64;
        var digest = new uint8[64];
        checksum.get_digest(digest, ref dig_len);
        digest.length = (int)dig_len;
        return digest;
    }

}