#include "socks4.h"

void Sock4Connect(cactus::IConn* conn, folly::SocketAddress endpoint, const std::string& user) {
    std::vector<char> buf;
    buf.push_back(4);
    buf.push_back(1);
    buf.push_back(endpoint.getPort() /  256);
    buf.push_back(endpoint.getPort() %  256);
    for (size_t index = 0; index < 4; ++index) {
        buf.push_back(endpoint.getIPAddress().getNthMSByte(index));
    }
    for (auto letter : user) {
        buf.push_back(letter);
    }
    buf.push_back('\0');
    conn->Write(cactus::View(buf));
    buf.resize(8);
    int n = conn->Read(cactus::View(buf));
    if (n != 8 || buf[0] != 0 || buf[1] != 90) {
        throw std::runtime_error("");
    }
}

std::unique_ptr<cactus::IConn> DialProxyChain(std::vector<Proxy> proxies, folly::SocketAddress
                                                                              endpoint) {
    proxies.push_back(Proxy{endpoint, ""});
    auto conn = cactus::DialTCP(proxies.begin()->proxy_address);
    for (size_t index = 0; index + 1 < proxies.size(); ++index) {
        Sock4Connect(conn.get(), proxies[index + 1].proxy_address, proxies[index].username);
    }
    return conn;
};