// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <OptionParser.h>
#include <cstddef>
#include <cstdio>
#include <cstring>
#include <signal.h>
#include <string>
#include <thread>
#include <unistd.h>

#include "Common/CommonTypes.h"
#include "Common/Event.h"
#include "Common/Flag.h"
#include "Common/Logging/LogManager.h"
#include "Common/MsgHandler.h"

#include "Core/Analytics.h"
#include "Core/Boot/Boot.h"
#include "Core/BootManager.h"
#include "Core/ConfigManager.h"
#include "Core/Core.h"
#include "Core/Host.h"
#include "Core/IOS/IOS.h"
#include "Core/IOS/STM/STM.h"
#include "Core/State.h"

#include "UICommon/CommandLineParse.h"
#ifdef USE_DISCORD_PRESENCE
#include "UICommon/DiscordPresence.h"
#endif
#include "UICommon/UICommon.h"

#include "VideoCommon/RenderBase.h"
#include "VideoCommon/VideoBackendBase.h"

static bool rendererHasFocus = true;
static bool rendererIsFullscreen = false;
static Common::Flag s_running{true};
static Common::Flag s_shutdown_requested{false};
static Common::Flag s_tried_graceful_shutdown{false};

static void signal_handler(int)
{
  const char message[] = "A signal was received. A second signal will force Dolphin to stop.\n";
  if (write(STDERR_FILENO, message, sizeof(message)) < 0)
  {
  }
  s_shutdown_requested.Set();
}

namespace ProcessorInterface
{
void PowerButton_Tap();
}

class Platform
{
public:
  virtual void Init() {}
  virtual void SetTitle(const std::string& title) {}
  virtual void MainLoop()
  {
    while (s_running.IsSet())
    {
      Core::HostDispatchJobs();
      std::this_thread::sleep_for(std::chrono::milliseconds(100));
    }
  }
  virtual void Shutdown() {}
  virtual ~Platform() {}

  virtual WindowSystemType GetWindowSystem() const { return WindowSystemType::Headless; }
  virtual void* GetDisplayHandle() const { return nullptr; }
  virtual void* GetWindowHandle() const { return nullptr; }
};

static Platform* platform;

void Host_NotifyMapLoaded()
{
}
void Host_RefreshDSPDebuggerWindow()
{
}

static Common::Event updateMainFrameEvent;
void Host_Message(HostMessageID id)
{
  if (id == HostMessageID::WMUserStop)
    s_running.Clear();
  if (id == HostMessageID::WMUserJobDispatch || id == HostMessageID::WMUserStop)
    updateMainFrameEvent.Set();
}

void Host_UpdateTitle(const std::string& title)
{
  platform->SetTitle(title);
}

void Host_UpdateDisasmDialog()
{
}

void Host_UpdateMainFrame()
{
  updateMainFrameEvent.Set();
}

void Host_RequestRenderWindowSize(int width, int height)
{
}

bool Host_UINeedsControllerState()
{
  return false;
}

bool Host_RendererHasFocus()
{
  return rendererHasFocus;
}

bool Host_RendererIsFullscreen()
{
  return rendererIsFullscreen;
}

void Host_YieldToUI()
{
}

void Host_UpdateProgressDialog(const char* caption, int position, int total)
{
}

#if HAVE_X11
#include <X11/Xatom.h>
#include <X11/Xlib.h>
#include <X11/keysym.h>
#include "UICommon/X11Utils.h"
#ifndef HOST_NAME_MAX
#include <climits>
#define HOST_NAME_MAX _POSIX_HOST_NAME_MAX
#endif

class PlatformX11 : public Platform
{
  Display* dpy;
  Window win;
  Cursor blankCursor = None;
#if defined(HAVE_XRANDR) && HAVE_XRANDR
  X11Utils::XRRConfiguration* XRRConfig;
#endif

  void Init() override
  {
    XInitThreads();
    dpy = XOpenDisplay(nullptr);
    if (!dpy)
    {
      PanicAlert("No X11 display found");
      exit(1);
    }

    win = XCreateSimpleWindow(dpy, DefaultRootWindow(dpy), SConfig::GetInstance().iRenderWindowXPos,
                              SConfig::GetInstance().iRenderWindowYPos,
                              SConfig::GetInstance().iRenderWindowWidth,
                              SConfig::GetInstance().iRenderWindowHeight, 0, 0, BlackPixel(dpy, 0));
    XSelectInput(dpy, win, StructureNotifyMask | KeyPressMask | FocusChangeMask);
    Atom wmProtocols[1];
    wmProtocols[0] = XInternAtom(dpy, "WM_DELETE_WINDOW", True);
    XSetWMProtocols(dpy, win, wmProtocols, 1);
    pid_t pid = getpid();
    XChangeProperty(dpy, win, XInternAtom(dpy, "_NET_WM_PID", False), XA_CARDINAL, 32,
                    PropModeReplace, reinterpret_cast<unsigned char*>(&pid), 1);
    char host_name[HOST_NAME_MAX] = "";
    if (!gethostname(host_name, sizeof(host_name)))
    {
      XTextProperty wmClientMachine = {reinterpret_cast<unsigned char*>(host_name), XA_STRING, 8,
                                       strlen(host_name)};
      XSetWMClientMachine(dpy, win, &wmClientMachine);
    }
    XMapRaised(dpy, win);
    XFlush(dpy);

    if (SConfig::GetInstance().bDisableScreenSaver)
      X11Utils::InhibitScreensaver(win, true);

#if defined(HAVE_XRANDR) && HAVE_XRANDR
    XRRConfig = new X11Utils::XRRConfiguration(dpy, win);
#endif

    if (SConfig::GetInstance().bHideCursor)
    {
      // make a blank cursor
      Pixmap Blank;
      XColor DummyColor;
      char ZeroData[1] = {0};
      Blank = XCreateBitmapFromData(dpy, win, ZeroData, 1, 1);
      blankCursor = XCreatePixmapCursor(dpy, Blank, Blank, &DummyColor, &DummyColor, 0, 0);
      XFreePixmap(dpy, Blank);
      XDefineCursor(dpy, win, blankCursor);
    }
  }

  void SetTitle(const std::string& string) override { XStoreName(dpy, win, string.c_str()); }
  void MainLoop() override
  {
    bool fullscreen = SConfig::GetInstance().bFullscreen;
    if (fullscreen)
    {
      rendererIsFullscreen = X11Utils::ToggleFullscreen(dpy, win);
#if defined(HAVE_XRANDR) && HAVE_XRANDR
      XRRConfig->ToggleDisplayMode(True);
#endif
    }

    // The actual loop
    while (s_running.IsSet())
    {
      if (s_shutdown_requested.TestAndClear())
      {
        const auto ios = IOS::HLE::GetIOS();
        const auto stm = ios ? ios->GetDeviceByName("/dev/stm/eventhook") : nullptr;
        if (!s_tried_graceful_shutdown.IsSet() && stm &&
            std::static_pointer_cast<IOS::HLE::Device::STMEventHook>(stm)->HasHookInstalled())
        {
          ProcessorInterface::PowerButton_Tap();
          s_tried_graceful_shutdown.Set();
        }
        else
        {
          s_running.Clear();
        }
      }

      XEvent event;
      KeySym key;
      for (int num_events = XPending(dpy); num_events > 0; num_events--)
      {
        XNextEvent(dpy, &event);
        switch (event.type)
        {
        case KeyPress:
          key = XLookupKeysym((XKeyEvent*)&event, 0);
          if (key == XK_Escape)
          {
            s_shutdown_requested.Set();
          }
          else if (key == XK_F10)
          {
            if (Core::GetState() == Core::State::Running)
            {
              if (SConfig::GetInstance().bHideCursor)
                XUndefineCursor(dpy, win);
              Core::SetState(Core::State::Paused);
            }
            else
            {
              if (SConfig::GetInstance().bHideCursor)
                XDefineCursor(dpy, win, blankCursor);
              Core::SetState(Core::State::Running);
            }
          }
          else if ((key == XK_Return) && (event.xkey.state & Mod1Mask))
          {
            fullscreen = !fullscreen;
            X11Utils::ToggleFullscreen(dpy, win);
#if defined(HAVE_XRANDR) && HAVE_XRANDR
            XRRConfig->ToggleDisplayMode(fullscreen);
#endif
          }
          else if (key >= XK_F1 && key <= XK_F8)
          {
            int slot_number = key - XK_F1 + 1;
            if (event.xkey.state & ShiftMask)
              State::Save(slot_number);
            else
              State::Load(slot_number);
          }
          else if (key == XK_F9)
            Core::SaveScreenShot();
          else if (key == XK_F11)
            State::LoadLastSaved();
          else if (key == XK_F12)
          {
            if (event.xkey.state & ShiftMask)
              State::UndoLoadState();
            else
              State::UndoSaveState();
          }
          break;
        case FocusIn:
          rendererHasFocus = true;
          if (SConfig::GetInstance().bHideCursor && Core::GetState() != Core::State::Paused)
            XDefineCursor(dpy, win, blankCursor);
          break;
        case FocusOut:
          rendererHasFocus = false;
          if (SConfig::GetInstance().bHideCursor)
            XUndefineCursor(dpy, win);
          break;
        case ClientMessage:
          if ((unsigned long)event.xclient.data.l[0] == XInternAtom(dpy, "WM_DELETE_WINDOW", False))
            s_shutdown_requested.Set();
          break;
        case ConfigureNotify:
        {
          if (g_renderer)
            g_renderer->ResizeSurface();
        }
        break;
        }
      }
      if (!fullscreen)
      {
        Window winDummy;
        unsigned int borderDummy, depthDummy;
        XGetGeometry(dpy, win, &winDummy, &SConfig::GetInstance().iRenderWindowXPos,
                     &SConfig::GetInstance().iRenderWindowYPos,
                     (unsigned int*)&SConfig::GetInstance().iRenderWindowWidth,
                     (unsigned int*)&SConfig::GetInstance().iRenderWindowHeight, &borderDummy,
                     &depthDummy);
        rendererIsFullscreen = false;
      }
      Core::HostDispatchJobs();
      usleep(100000);
    }
  }

  void Shutdown() override
  {
#if defined(HAVE_XRANDR) && HAVE_XRANDR
    delete XRRConfig;
#endif

    if (SConfig::GetInstance().bHideCursor)
      XFreeCursor(dpy, blankCursor);

    XCloseDisplay(dpy);
  }

  WindowSystemType GetWindowSystem() const override { return WindowSystemType::X11; }
  void* GetDisplayHandle() const override { return static_cast<void*>(dpy); }
  void* GetWindowHandle() const override { return reinterpret_cast<void*>(win); }
};
#endif

static Platform* GetPlatform()
{
#if defined(USE_HEADLESS)
  return new Platform();
#elif HAVE_X11
  return new PlatformX11();
#endif
  return nullptr;
}

int main(int argc, char* argv[])
{
  auto parser = CommandLineParse::CreateParser(CommandLineParse::ParserOptions::OmitGUIOptions);
  optparse::Values& options = CommandLineParse::ParseArguments(parser.get(), argc, argv);
  std::vector<std::string> args = parser->args();

  std::unique_ptr<BootParameters> boot;
  if (options.is_set("exec"))
  {
    boot = BootParameters::GenerateFromFile(static_cast<const char*>(options.get("exec")));
  }
  else if (options.is_set("nand_title"))
  {
    const std::string hex_string = static_cast<const char*>(options.get("nand_title"));
    if (hex_string.length() != 16)
    {
      fprintf(stderr, "Invalid title ID\n");
      parser->print_help();
      return 1;
    }
    const u64 title_id = std::stoull(hex_string, nullptr, 16);
    boot = std::make_unique<BootParameters>(BootParameters::NANDTitle{title_id});
  }
  else if (args.size())
  {
    boot = BootParameters::GenerateFromFile(args.front());
    args.erase(args.begin());
  }
  else
  {
    parser->print_help();
    return 0;
  }

  std::string user_directory;
  if (options.is_set("user"))
  {
    user_directory = static_cast<const char*>(options.get("user"));
  }

  platform = GetPlatform();
  if (!platform)
  {
    fprintf(stderr, "No platform found\n");
    return 1;
  }

  UICommon::SetUserDirectory(user_directory);
  UICommon::Init();

  Core::SetOnStateChangedCallback([](Core::State state) {
    if (state == Core::State::Uninitialized)
      s_running.Clear();
  });
  platform->Init();

  // Shut down cleanly on SIGINT and SIGTERM
  struct sigaction sa;
  sa.sa_handler = signal_handler;
  sigemptyset(&sa.sa_mask);
  sa.sa_flags = SA_RESETHAND;
  sigaction(SIGINT, &sa, nullptr);
  sigaction(SIGTERM, &sa, nullptr);

  DolphinAnalytics::Instance()->ReportDolphinStart("nogui");

  WindowSystemInfo wsi(platform->GetWindowSystem(), platform->GetDisplayHandle(),
                       platform->GetWindowHandle());

  if (!BootManager::BootCore(std::move(boot), wsi))
  {
    fprintf(stderr, "Could not boot the specified file\n");
    return 1;
  }

#ifdef USE_DISCORD_PRESENCE
  Discord::UpdateDiscordPresence();
#endif

  while (!Core::IsRunning() && s_running.IsSet())
  {
    Core::HostDispatchJobs();
    updateMainFrameEvent.Wait();
  }

  if (s_running.IsSet())
    platform->MainLoop();
  Core::Stop();

  Core::Shutdown();
  platform->Shutdown();
  UICommon::Shutdown();

  delete platform;

  return 0;
}