#include <llarp.hpp>
#include "constants/version.hpp"
#include "constants/evloop.hpp"

#include "config/config.hpp"
#include "crypto/crypto_libsodium.hpp"
#include "dht/context.hpp"
#include "ev/ev.hpp"
#include "ev/vpnio.hpp"
#include <memory>
#include "nodedb.hpp"
#include "router/router.hpp"
#include "service/context.hpp"
#include "util/logging/logger.hpp"

#include <cxxopts.hpp>
#include <csignal>
#include <stdexcept>

#if (__FreeBSD__) || (__OpenBSD__) || (__NetBSD__)
#include <pthread_np.h>
#endif

namespace llarp
{
  bool
  Context::CallSafe(std::function<void(void)> f)
  {
    if (!loop)
      return false;
    loop->call(std::move(f));
    return true;
  }

  void
  Context::Configure(std::shared_ptr<Config> conf)
  {
    if (nullptr != config.get())
      throw std::runtime_error("Config already exists");

    config = std::move(conf);

    nodedb_dir = fs::path{config->router.m_dataDir / nodedb_dirname}.string();
  }

  bool
  Context::IsUp() const
  {
    return router && router->IsRunning();
  }

  bool
  Context::LooksAlive() const
  {
    return router && router->LooksAlive();
  }

  void
  Context::Setup(const RuntimeOptions& opts)
  {
    /// Call one of the Configure() methods before calling Setup()
    if (not config)
      throw std::runtime_error("Cannot call Setup() on context without a Config");

    llarp::LogInfo(llarp::VERSION_FULL, " ", llarp::RELEASE_MOTTO);
    llarp::LogInfo("starting up");
    if (!loop)
    {
      auto jobQueueSize = std::max(event_loop_queue_size, config->router.m_JobQueueSize);
      loop = EventLoop::create(jobQueueSize);
    }

    crypto = std::make_shared<sodium::CryptoLibSodium>();
    cryptoManager = std::make_shared<CryptoManager>(crypto.get());

    router = makeRouter(loop);

    nodedb = std::make_shared<NodeDB>(
        nodedb_dir, [r = router.get()](auto call) { r->QueueDiskIO(std::move(call)); });

    if (!router->Configure(config, opts.isRouter, nodedb))
      throw std::runtime_error("Failed to configure router");
  }

  std::shared_ptr<AbstractRouter>
  Context::makeRouter(const EventLoop_ptr& loop)
  {
    return std::static_pointer_cast<AbstractRouter>(
        std::make_shared<Router>(loop, makeVPNPlatform()));
  }

  std::shared_ptr<vpn::Platform>
  Context::makeVPNPlatform()
  {
    auto plat = vpn::MakeNativePlatform(this);
    if (plat == nullptr)
      throw std::runtime_error("vpn platform not supported");
    return plat;
  }

  int
  Context::Run(const RuntimeOptions& opts)
  {
    if (router == nullptr)
    {
      // we are not set up so we should die
      llarp::LogError("cannot run non configured context");
      return 1;
    }

    if (!opts.background)
    {
      if (!router->Run())
        return 2;
    }

    // run net io thread
    llarp::LogInfo("running mainloop");

    loop->run();
    if (closeWaiter)
    {
      closeWaiter->set_value();
    }
    Close();
    return 0;
  }

  void
  Context::CloseAsync()
  {
    /// already closing
    if (closeWaiter)
      return;

    if (CallSafe(std::bind(&Context::HandleSignal, this, SIGTERM)))
      closeWaiter = std::make_unique<std::promise<void>>();
  }

  void
  Context::Wait()
  {
    if (closeWaiter)
    {
      closeWaiter->get_future().wait();
      closeWaiter.reset();
    }
  }

  void
  Context::HandleSignal(int sig)
  {
    if (sig == SIGINT || sig == SIGTERM)
    {
      SigINT();
    }
#ifndef _WIN32
    if (sig == SIGHUP)
    {
      Reload();
    }
#endif
  }

  void
  Context::Reload()
  {}

  void
  Context::SigINT()
  {
    if (router)
    {
      /// async stop router on sigint
      router->Stop();
    }
  }

  void
  Context::Close()
  {
    llarp::LogDebug("free config");
    config.reset();

    llarp::LogDebug("free nodedb");
    nodedb.reset();

    llarp::LogDebug("free router");
    router.reset();

    llarp::LogDebug("free loop");
    loop.reset();
  }

#if defined(ANDROID)
  int
  Context::GetUDPSocket()
  {
    return router->GetOutboundUDPSocket();
  }
#endif

}  // namespace llarp

extern "C"
{
  ssize_t
  llarp_vpn_io_readpkt(struct llarp_vpn_pkt_reader* r, unsigned char* dst, size_t dstlen)
  {
    if (r == nullptr)
      return -1;
    if (not r->queue.enabled())
      return -1;
    auto pkt = r->queue.popFront();
    ManagedBuffer mbuf = pkt.ConstBuffer();
    const llarp_buffer_t& buf = mbuf;
    if (buf.sz > dstlen || buf.sz == 0)
      return -1;
    std::copy_n(buf.base, buf.sz, dst);
    return buf.sz;
  }

  bool
  llarp_vpn_io_writepkt(struct llarp_vpn_pkt_writer* w, unsigned char* pktbuf, size_t pktlen)
  {
    if (pktlen == 0 || pktbuf == nullptr)
      return false;
    if (w == nullptr)
      return false;
    llarp_vpn_pkt_queue::Packet_t pkt;
    llarp_buffer_t buf(pktbuf, pktlen);
    if (not pkt.Load(buf))
      return false;
    return w->queue.pushBack(std::move(pkt)) == llarp::thread::QueueReturn::Success;
  }

  bool
  llarp_main_inject_vpn_by_name(
      llarp::Context* ctx,
      const char* name,
      struct llarp_vpn_io* io,
      struct llarp_vpn_ifaddr_info info)
  {
    if (name == nullptr || io == nullptr)
      return false;
    if (ctx == nullptr || ctx->router == nullptr)
      return false;
    auto ep = ctx->router->hiddenServiceContext().GetEndpointByName(name);
    return ep && ep->InjectVPN(io, info);
  }

  void
  llarp_vpn_io_close_async(struct llarp_vpn_io* io)
  {
    if (io == nullptr || io->impl == nullptr)
      return;
    static_cast<llarp_vpn_io_impl*>(io->impl)->AsyncClose();
  }

  bool
  llarp_vpn_io_init(llarp::Context* ctx, struct llarp_vpn_io* io)
  {
    if (io == nullptr || ctx == nullptr)
      return false;
    llarp_vpn_io_impl* impl = new llarp_vpn_io_impl(ctx, io);
    io->impl = impl;
    return true;
  }

  struct llarp_vpn_pkt_writer*
  llarp_vpn_io_packet_writer(struct llarp_vpn_io* io)
  {
    if (io == nullptr || io->impl == nullptr)
      return nullptr;
    llarp_vpn_io_impl* vpn = static_cast<llarp_vpn_io_impl*>(io->impl);
    return &vpn->writer;
  }

  struct llarp_vpn_pkt_reader*
  llarp_vpn_io_packet_reader(struct llarp_vpn_io* io)
  {
    if (io == nullptr || io->impl == nullptr)
      return nullptr;
    llarp_vpn_io_impl* vpn = static_cast<llarp_vpn_io_impl*>(io->impl);
    return &vpn->reader;
  }
}