extern "C" {
#include <arpa/inet.h>
}

#include <expected>
#include <string>
#include <cstring>
#include <iostream>
#include <format>
#include <cstdint>

#include <msgheader.hpp>

const std::string internetPkgMsg = "internetPkg";
const std::string tunAddressMsg = "tunAddress";
const std::string localRouteMsg = "localRoute";

MessageHeader::MessageHeader(const uint32_t ipSize) {
        pSize = ipSize;
}

MessageHeader::MessageHeader(void) {
        pSize = 0;
}

std::string MessageHeader::Encode() {
        std::string buffer, tmp;
        auto magic = htonl(msgMagic);
        tmp = std::string(reinterpret_cast<const char*>(&magic), sizeof(magic));
        buffer.append(tmp);

        auto size = htonl(pSize);
        tmp = std::string(reinterpret_cast<const char*>(&size), sizeof(size));
        buffer.append(tmp);
        return buffer;
}

std::expected<void, std::string> MessageHeader::Decode(const std::string rawHeader) {
        uint32_t tmp;
        std::memcpy(&tmp, rawHeader.data(), sizeof(uint32_t));
        auto magic = ntohl(tmp);
        if (magic != msgMagic) {
                return std::unexpected(std::format("Wrong magic code {:x}", magic));
        }
        std::memcpy(&tmp, rawHeader.data() + sizeof(uint32_t), sizeof(uint32_t));
        pSize = ntohl(tmp);
        return {};
}

uint32_t MessageHeader::PayloadSize() {
        return pSize;
}