/*
 * This file is part of the Flowee project
 * Copyright (C) 2020-2024 Tom Zander <tom@flowee.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#include "NetworkEndPoint.h"

#include <sstream>

EndPoint EndPoint::fromAddr(const std::vector<char> &addr, int16_t port)
{
    assert(addr.size() == 16);
    // IPv4 is encoded by having the first 10 bytes as zero, then 2 bytes of 255
    bool isIPv4 = addr[10] == static_cast<char>(-1) && addr[11] == static_cast<char>(-1);
    for (int i = 0; isIPv4 && i < 10; ++i) {
        isIPv4 = addr[0] == 0;
    }

    if (isIPv4) {
        std::array<uint8_t,4> ipv4;
        for (int i = 0; i < 4; ++i)
            ipv4[i] = addr[i + 12];
        return EndPoint(boost::asio::ip::address_v4(ipv4), port);
    }

    std::array<uint8_t,16> ipv6;
    for (int i = 0; i < 16; ++i)
        ipv6[i] = addr[i];

    return EndPoint(boost::asio::ip::address_v6(ipv6), port);
}

bool EndPoint::operator==(const EndPoint &other) const
{
    const bool hasHostname = (!other.ipAddress.is_unspecified() || !other.hostname.empty()) && other.announcePort > 0;
    if (encrypted != other.encrypted)
        return false;

    if (hasHostname) {
        if (!other.hostname.empty() && hostname != other.hostname)
            return false;
        if (!other.ipAddress.is_unspecified() && ipAddress != other.ipAddress)
            return false;
        if (!(announcePort == 0 || announcePort == other.announcePort || other.announcePort == 0))
            return false;
        return true;
    }
    // both empty, perhaps?
    return ipAddress.is_unspecified() && hostname.empty() && announcePort == 0;
}

void EndPoint::toAddr(char *addr) const
{
    for (size_t i = 0; i < 16; ++i) {
        addr[i] = 0;
    }

    if (ipAddress.is_v4()) {
        addr[10] = addr[11] = -1;
        size_t index = 12;
        for (auto byte : ipAddress.to_v4().to_bytes()) {
            assert(index <= 16);
            addr[index++] = byte;
        }
    }
    else if (ipAddress.is_v6()) {
        size_t index = 0;
        for (auto byte : ipAddress.to_v6().to_bytes()) {
            assert(index <= 16);
            addr[index++] = byte;
        }
    }
}

std::string EndPoint::toString() const
{
    std::ostringstream answer;
    if (ipAddress.is_unspecified()) {
        answer << hostname;
    }
    else {
        if (ipAddress.is_v6())
            answer << "[";
        answer << ipAddress.to_string().c_str();
        if (ipAddress.is_v6())
            answer << "]";
    }
    answer << ':' << announcePort;
    if (announcePort != peerPort && peerPort != 0)
        answer << '|' << peerPort;
    if (encrypted)
        answer << " (ssl)";
    return answer.str();
}