#include <Limelight.h>
#include <SDL.h>
#include "streaming/session.h"
#include "settings/mappingmanager.h"
#include "path.h"

#include <QtGlobal>
#include <QDir>

#define MOUSE_POLLING_INTERVAL 5

SdlInputHandler::SdlInputHandler(StreamingPreferences& prefs, NvComputer*, int streamWidth, int streamHeight)
    : m_MultiController(prefs.multiController),
      m_GamepadMouse(prefs.gamepadMouse),
      m_MouseMoveTimer(0),
      m_FakeCaptureActive(false),
      m_LongPressTimer(0),
      m_StreamWidth(streamWidth),
      m_StreamHeight(streamHeight),
      m_AbsoluteMouseMode(prefs.absoluteMouseMode),
      m_AbsoluteTouchMode(prefs.absoluteTouchMode),
      m_LeftButtonReleaseTimer(0),
      m_RightButtonReleaseTimer(0),
      m_DragTimer(0),
      m_DragButton(0),
      m_NumFingersDown(0)
{
    // Allow gamepad input when the app doesn't have focus
    SDL_SetHint(SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS, "1");

    // If absolute mouse mode is enabled, use relative mode warp (which
    // is via normal motion events that are influenced by mouse acceleration).
    // Otherwise, we'll use raw input capture which is straight from the device
    // without modification by the OS.
    SDL_SetHintWithPriority(SDL_HINT_MOUSE_RELATIVE_MODE_WARP,
                            prefs.absoluteMouseMode ? "1" : "0",
                            SDL_HINT_OVERRIDE);

    // Allow clicks to pass through to us when focusing the window. If we're in
    // absolute mouse mode, this will avoid the user having to click twice to
    // trigger a click on the host if the Moonlight window is not focused. In
    // relative mode, the click event will trigger the mouse to be recaptured.
    SDL_SetHint(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, "1");

#if defined(Q_OS_DARWIN) && !SDL_VERSION_ATLEAST(2, 0, 10)
    // SDL 2.0.9 on macOS has a broken HIDAPI mapping for the older Xbox One S
    // firmware, so we have to disable HIDAPI for Xbox gamepads on macOS until
    // SDL 2.0.10 where the bug is fixed.
    // https://github.com/moonlight-stream/moonlight-qt/issues/133
    // https://bugzilla.libsdl.org/show_bug.cgi?id=4395
    SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI_XBOX, "0");
#endif

#if SDL_VERSION_ATLEAST(2, 0, 9)
    // Enabling extended input reports allows rumble to function on Bluetooth PS4
    // controllers, but breaks DirectInput applications. We will enable it because
    // it's likely that working rumble is what the user is expecting. If they don't
    // want this behavior, they can override it with the environment variable.
    SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE, "1");
#endif

    // We must initialize joystick explicitly before gamecontroller in order
    // to ensure we receive gamecontroller attach events for gamepads where
    // SDL doesn't have a built-in mapping. By starting joystick first, we
    // can allow mapping manager to update the mappings before GC attach
    // events are generated.
    SDL_assert(!SDL_WasInit(SDL_INIT_JOYSTICK));
    if (SDL_InitSubSystem(SDL_INIT_JOYSTICK) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "SDL_InitSubSystem(SDL_INIT_JOYSTICK) failed: %s",
                     SDL_GetError());
    }

    MappingManager mappingManager;
    mappingManager.applyMappings();

    // Flush gamepad arrival and departure events which may be queued before
    // starting the gamecontroller subsystem again. This prevents us from
    // receiving duplicate arrival and departure events for the same gamepad.
    SDL_FlushEvent(SDL_CONTROLLERDEVICEADDED);
    SDL_FlushEvent(SDL_CONTROLLERDEVICEREMOVED);

    // We need to reinit this each time, since you only get
    // an initial set of gamepad arrival events once per init.
    SDL_assert(!SDL_WasInit(SDL_INIT_GAMECONTROLLER));
    if (SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER) failed: %s",
                     SDL_GetError());
    }

#if !SDL_VERSION_ATLEAST(2, 0, 9)
    SDL_assert(!SDL_WasInit(SDL_INIT_HAPTIC));
    if (SDL_InitSubSystem(SDL_INIT_HAPTIC) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "SDL_InitSubSystem(SDL_INIT_HAPTIC) failed: %s",
                     SDL_GetError());
    }
#endif

    // Initialize the gamepad mask with currently attached gamepads to avoid
    // causing gamepads to unexpectedly disappear and reappear on the host
    // during stream startup as we detect currently attached gamepads one at a time.
    m_GamepadMask = getAttachedGamepadMask();

    SDL_zero(m_GamepadState);
    SDL_zero(m_LastTouchDownEvent);
    SDL_zero(m_LastTouchUpEvent);
    SDL_zero(m_TouchDownEvent);

    SDL_AtomicSet(&m_MouseDeltaX, 0);
    SDL_AtomicSet(&m_MouseDeltaY, 0);

    Uint32 pollingInterval = QString(qgetenv("MOUSE_POLLING_INTERVAL")).toUInt();
    if (pollingInterval == 0) {
        pollingInterval = MOUSE_POLLING_INTERVAL;
    }
    else {
        SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
                    "Using custom mouse polling interval: %u ms",
                    pollingInterval);
    }

    m_MouseMoveTimer = SDL_AddTimer(pollingInterval, SdlInputHandler::mouseMoveTimerCallback, this);
}

SdlInputHandler::~SdlInputHandler()
{
    for (int i = 0; i < MAX_GAMEPADS; i++) {
        if (m_GamepadState[i].mouseEmulationTimer != 0) {
            Session::get()->notifyMouseEmulationMode(false);
            SDL_RemoveTimer(m_GamepadState[i].mouseEmulationTimer);
        }
#if !SDL_VERSION_ATLEAST(2, 0, 9)
        if (m_GamepadState[i].haptic != nullptr) {
            SDL_HapticClose(m_GamepadState[i].haptic);
        }
#endif
        if (m_GamepadState[i].controller != nullptr) {
            SDL_GameControllerClose(m_GamepadState[i].controller);
        }
    }

    SDL_RemoveTimer(m_MouseMoveTimer);
    SDL_RemoveTimer(m_LongPressTimer);
    SDL_RemoveTimer(m_LeftButtonReleaseTimer);
    SDL_RemoveTimer(m_RightButtonReleaseTimer);
    SDL_RemoveTimer(m_DragTimer);

#if !SDL_VERSION_ATLEAST(2, 0, 9)
    SDL_QuitSubSystem(SDL_INIT_HAPTIC);
    SDL_assert(!SDL_WasInit(SDL_INIT_HAPTIC));
#endif

    SDL_QuitSubSystem(SDL_INIT_GAMECONTROLLER);
    SDL_assert(!SDL_WasInit(SDL_INIT_GAMECONTROLLER));

    SDL_QuitSubSystem(SDL_INIT_JOYSTICK);
    SDL_assert(!SDL_WasInit(SDL_INIT_JOYSTICK));

    // Return background event handling to off
    SDL_SetHint(SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS, "0");

#ifdef STEAM_LINK
    // Hide SDL's cursor on Steam Link after quitting the stream.
    // FIXME: We should also do this for other situations where SDL
    // and Qt will draw their own mouse cursors like KMSDRM or RPi
    // video backends.
    SDL_ShowCursor(SDL_DISABLE);
#endif
}

void SdlInputHandler::setWindow(SDL_Window *window)
{
    m_Window = window;
}

void SdlInputHandler::raiseAllKeys()
{
    if (m_KeysDown.isEmpty()) {
        return;
    }

    SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION,
                "Raising %d keys",
                m_KeysDown.count());

    for (auto keyDown : m_KeysDown) {
        LiSendKeyboardEvent(keyDown, KEY_ACTION_UP, 0);
    }

    m_KeysDown.clear();
}

void SdlInputHandler::notifyFocusLost()
{
    // Release mouse cursor when another window is activated (e.g. by using ALT+TAB).
    // This lets user to interact with our window's title bar and with the buttons in it.
    // Doing this while the window is full-screen breaks the transition out of FS
    // (desktop and exclusive), so we must check for that before releasing mouse capture.
    if (!(SDL_GetWindowFlags(m_Window) & SDL_WINDOW_FULLSCREEN) && !m_AbsoluteMouseMode) {
        setCaptureActive(false);
    }

    // Raise all keys that are currently pressed. If we don't do this, certain keys
    // used in shortcuts that cause focus loss (such as Alt+Tab) may get stuck down.
    raiseAllKeys();
}

bool SdlInputHandler::isCaptureActive()
{
    if (SDL_GetRelativeMouseMode()) {
        return true;
    }

    // Some platforms don't support SDL_SetRelativeMouseMode
    return m_FakeCaptureActive;
}

void SdlInputHandler::setCaptureActive(bool active)
{
    if (active) {
        // If we're in full-screen exclusive mode, grab the cursor so it can't accidentally leave our window.
        if ((SDL_GetWindowFlags(m_Window) & SDL_WINDOW_FULLSCREEN_DESKTOP) == SDL_WINDOW_FULLSCREEN) {
            SDL_SetWindowGrab(m_Window, SDL_TRUE);
        }

        if (!m_AbsoluteMouseMode) {
            // If our window is occluded when mouse is captured, the mouse may
            // get stuck on top of the occluding window and not be properly
            // captured. We can avoid this by raising our window before we
            // capture the mouse.
            SDL_RaiseWindow(m_Window);
        }

        // If we're in relative mode, try to activate SDL's relative mouse mode
        if (m_AbsoluteMouseMode || SDL_SetRelativeMouseMode(SDL_TRUE) < 0) {
            // Relative mouse mode didn't work or was disabled, so we'll just hide the cursor
            SDL_ShowCursor(SDL_DISABLE);
            m_FakeCaptureActive = true;
        }
    }
    else {
        if (m_FakeCaptureActive) {
            // Display the cursor again
            SDL_ShowCursor(SDL_ENABLE);
            m_FakeCaptureActive = false;
        }
        else {
            SDL_SetRelativeMouseMode(SDL_FALSE);
        }

        // Allow the cursor to leave the bounds of our window again.
        SDL_SetWindowGrab(m_Window, SDL_FALSE);
    }
}

void SdlInputHandler::handleTouchFingerEvent(SDL_TouchFingerEvent* event)
{
#if SDL_VERSION_ATLEAST(2, 0, 10)
    if (SDL_GetTouchDeviceType(event->touchId) != SDL_TOUCH_DEVICE_DIRECT) {
        // Ignore anything that isn't a touchscreen. We may get callbacks
        // for trackpads, but we want to handle those in the mouse path.
        return;
    }
#elif defined(Q_OS_DARWIN)
    // SDL2 sends touch events from trackpads by default on
    // macOS. This totally screws our actual mouse handling,
    // so we must explicitly ignore touch events on macOS
    // until SDL 2.0.10 where we have SDL_GetTouchDeviceType()
    // to tell them apart.
    return;
#endif

    if (m_AbsoluteTouchMode) {
        handleAbsoluteFingerEvent(event);
    }
    else {
        handleRelativeFingerEvent(event);
    }
}