//
// Copyright (c) 2008-2015 the Urho3D project.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#include "../Core/Context.h"
#include "../Core/CoreEvents.h"
#include "../IO/FileSystem.h"
#include "../Graphics/Graphics.h"
#include "../Graphics/GraphicsEvents.h"
#include "../Graphics/GraphicsImpl.h"
#include "../Input/Input.h"
#include "../IO/Log.h"
#include "../Core/Mutex.h"
#include "../Core/ProcessUtils.h"
#include "../Core/Profiler.h"
#include "../Resource/ResourceCache.h"
#include "../IO/RWOpsWrapper.h"
#include "../Core/StringUtils.h"
#include "../UI/Text.h"
#include "../UI/UI.h"

#include <cstring>

#include <SDL/include/SDL.h>
#ifdef EMSCRIPTEN
#include <emscripten/html5.h>
#endif

#include "../DebugNew.h"

extern "C" int SDL_AddTouch(SDL_TouchID touchID, const char *name);

// Require a click inside window before re-hiding mouse cursor on OSX, otherwise dragging the window
// can be incorrectly interpreted as mouse movement inside the window
#if defined(__APPLE__) && !defined(IOS)
    #define REQUIRE_CLICK_TO_FOCUS
#endif

namespace Atomic
{

const int SCREEN_JOYSTICK_START_ID = 0x40000000;
const StringHash VAR_BUTTON_KEY_BINDING("VAR_BUTTON_KEY_BINDING");
const StringHash VAR_BUTTON_MOUSE_BUTTON_BINDING("VAR_BUTTON_MOUSE_BUTTON_BINDING");
const StringHash VAR_LAST_KEYSYM("VAR_LAST_KEYSYM");
const StringHash VAR_SCREEN_JOYSTICK_ID("VAR_SCREEN_JOYSTICK_ID");

const unsigned TOUCHID_MAX = 32;

/// Convert SDL keycode if necessary.
int ConvertSDLKeyCode(int keySym, int scanCode)
{
    if (scanCode == SCANCODE_AC_BACK)
        return KEY_ESC;
    else
        return SDL_toupper(keySym);
}

UIElement* TouchState::GetTouchedElement()
{
    return touchedElement_.Get();
}

#ifdef EMSCRIPTEN
#define EM_TRUE 1

/// Glue between Urho Input and Emscripten HTML5
/** HTML5 (Emscripten) is limited in the way it handles input. The EmscriptenInput class attempts to provide the glue between Urho3D Input behavior and HTML5, where SDL currently fails to do so.
 *
 * Mouse Input:
 * - The OS mouse cursor position can't be set.
 * - The mouse can be trapped within play area via 'PointerLock API', which requires a request and interaction between the user and browser.
 * - To request mouse lock, call SetMouseMode(MM_RELATIVE). The E_MOUSEMODECHANGED event will be sent if/when the user confirms the request.
 * NOTE: The request must be initiated by the user (eg: on mouse button down/up, key down/up).
 * - The user can press 'escape' key and browser will force user out of pointer lock. Urho will send the E_MOUSEMODECHANGED event.
 * - SetMouseMode(MM_ABSOLUTE) will leave pointer lock.
 * - MM_WRAP is unsupported.
 */
/// % Emscripten Input glue. Intended to be used by the Input subsystem only.
class EmscriptenInput
{
public:
    /// Constructor, expecting pointer to constructing Input instance.
    EmscriptenInput(Input* inputInst);

    /// Static callback method for Pointer Lock API. Handles change in Pointer Lock state and sends events for mouse mode change.
    static EM_BOOL HandlePointerLockChange(int eventType, const EmscriptenPointerlockChangeEvent* keyEvent, void* userData);
    /// Static callback method for tracking focus change events.
    static EM_BOOL HandleFocusChange(int eventType, const EmscriptenFocusEvent* keyEvent, void* userData);

    /// Send request to user to gain pointer lock. This requires a user-browser interaction on the first call.
    void RequestPointerLock();
    /// Send request to exit pointer lock. This has the benefit of not requiring the user-browser interaction on the next pointer lock request.
    void ExitPointerLock();
    /// Returns whether the page is visible.
    bool IsVisible();

private:
    /// Instance of Input subsystem that constructed this instance.
    Input* inputInst_;
};

EmscriptenInput::EmscriptenInput(Input* inputInst)
{
    inputInst_ = inputInst;
    void* vInputInst = (void*)inputInst;
    emscripten_set_pointerlockchange_callback(NULL, vInputInst, false, EmscriptenInput::HandlePointerLockChange);

    // Handle focus changes:
    emscripten_set_blur_callback(NULL, vInputInst, false, EmscriptenInput::HandleFocusChange);
    emscripten_set_focus_callback(NULL, vInputInst, false, EmscriptenInput::HandleFocusChange);
}

void EmscriptenInput::RequestPointerLock()
{
    emscripten_request_pointerlock(NULL, true);
}

void EmscriptenInput::ExitPointerLock()
{
    inputInst_->emscriptenExitingPointerLock_ = true;
    emscripten_exit_pointerlock();
}

bool EmscriptenInput::IsVisible()
{
    EmscriptenVisibilityChangeEvent visibilityStatus;
    if (emscripten_get_visibility_status(&visibilityStatus) >= EMSCRIPTEN_RESULT_SUCCESS)
        return visibilityStatus.hidden >= EM_TRUE ? false : true;

    // Assume visible
    LOGWARNING("Could not determine visibility status.");
    return true;
}

EM_BOOL EmscriptenInput::HandlePointerLockChange(int eventType, const EmscriptenPointerlockChangeEvent* keyEvent, void* userData)
{
    Input* inputInst = (Input*)userData;
    if (keyEvent->isActive >= EM_TRUE)
    {
        // Pointer Lock is now active
        inputInst->emscriptenEnteredPointerLock_ = true;
        inputInst->SetMouseModeEmscripten(MM_RELATIVE);
    }
    else
    {
        // Pointer Lock is now inactive
        inputInst->SetMouseModeEmscripten(MM_ABSOLUTE);
    }
    return EM_TRUE;
}

EM_BOOL EmscriptenInput::HandleFocusChange(int eventType, const EmscriptenFocusEvent* keyEvent, void* userData)
{
    Input* inputInst = (Input*)userData;
    if (eventType == EMSCRIPTEN_EVENT_BLUR)
        inputInst->LoseFocus();
    else if (eventType == EMSCRIPTEN_EVENT_FOCUS)
        inputInst->GainFocus();
    return EM_TRUE;
}
#endif

void JoystickState::Initialize(unsigned numButtons, unsigned numAxes, unsigned numHats)
{
    buttons_.Resize(numButtons);
    buttonPress_.Resize(numButtons);
    axes_.Resize(numAxes);
    hats_.Resize(numHats);

    Reset();
}

void JoystickState::Reset()
{
    for (unsigned i = 0; i < buttons_.Size(); ++i)
    {
        buttons_[i] = false;
        buttonPress_[i] = false;
    }
    for (unsigned i = 0; i < axes_.Size(); ++i)
        axes_[i] = 0.0f;
    for (unsigned i = 0; i < hats_.Size(); ++i)
        hats_[i] = HAT_CENTER;
}

Input::Input(Context* context) :
    Object(context),
    mouseButtonDown_(0),
    mouseButtonPress_(0),
    mouseMoveWheel_(0),
    windowID_(0),
    toggleFullscreen_(true),
    mouseVisible_(false),
    lastMouseVisible_(false),
    mouseGrabbed_(false),
    mouseMode_(MM_ABSOLUTE),
#ifdef EMSCRIPTEN
    emscriptenExitingPointerLock_(false),
    emscriptenEnteredPointerLock_(false),
#endif
    lastVisibleMousePosition_(MOUSE_POSITION_OFFSCREEN),
    touchEmulation_(false),
    inputFocus_(false),
    minimized_(false),
    focusedThisFrame_(false),
    suppressNextMouseMove_(false),
    initialized_(false)
{
    for (int i = 0; i < TOUCHID_MAX; i++)
        availableTouchIDs_.Push(i);

    SubscribeToEvent(E_SCREENMODE, HANDLER(Input, HandleScreenMode));

    #ifdef EMSCRIPTEN
    emscriptenInput_ = new EmscriptenInput(this);
    #endif

    // Try to initialize right now, but skip if screen mode is not yet set
    Initialize();
}

Input::~Input()
{
    #ifdef EMSCRIPTEN
    delete emscriptenInput_;
    emscriptenInput_ = 0;
    #endif
}

void Input::Update()
{
    assert(initialized_);

    PROFILE(UpdateInput);

    // Reset input accumulation for this frame
    keyPress_.Clear();
    scancodePress_.Clear();
    mouseButtonPress_ = 0;
    mouseMove_ = IntVector2::ZERO;
    mouseMoveWheel_ = 0;
    for (HashMap<SDL_JoystickID, JoystickState>::Iterator i = joysticks_.Begin(); i != joysticks_.End(); ++i)
    {
        for (unsigned j = 0; j < i->second_.buttonPress_.Size(); ++j)
            i->second_.buttonPress_[j] = false;
    }

    // Reset touch delta movement
    for (HashMap<int, TouchState>::Iterator i = touches_.Begin(); i != touches_.End(); ++i)
    {
        TouchState& state = i->second_;
        state.lastPosition_ = state.position_;
        state.delta_ = IntVector2::ZERO;
    }

    // Check and handle SDL events

    if (!inputFocus_)
    {
        // While there is no input focus, don't process key, mouse, touch or joystick events.
        SDL_PumpEvents();
        SDL_FlushEvents(SDL_KEYDOWN, SDL_MULTIGESTURE);
    }

    SDL_Event evt;
    while (SDL_PollEvent(&evt))
        HandleSDLEvent(&evt);

    // Check for focus change this frame
    SDL_Window* window = graphics_->GetImpl()->GetWindow();
    unsigned flags = window ? SDL_GetWindowFlags(window) & (SDL_WINDOW_INPUT_FOCUS | SDL_WINDOW_MOUSE_FOCUS) : 0;
#ifndef EMSCRIPTEN
    if (window)
    {
#if defined(REQUIRE_CLICK_TO_FOCUS)
        if (!inputFocus_ && (graphics_->GetFullscreen() || mouseVisible_) && flags == (SDL_WINDOW_INPUT_FOCUS |
            SDL_WINDOW_MOUSE_FOCUS))
#else
        if (!inputFocus_ && (flags & SDL_WINDOW_INPUT_FOCUS))
#endif
            focusedThisFrame_ = true;

        if (focusedThisFrame_)
            GainFocus();

        if (inputFocus_ && (flags & SDL_WINDOW_INPUT_FOCUS) == 0)
            LoseFocus();
    }
    else
        return;

    // Handle mouse mode MM_WRAP
    if (mouseVisible_ && mouseMode_ == MM_WRAP)
    {
        IntVector2 mpos;
        SDL_GetMouseState(&mpos.x_, &mpos.y_);

        const int buffer = 5;
        int width = graphics_->GetWidth() - buffer * 2;
        int height = graphics_->GetHeight() - buffer * 2;

        bool warp = false;
        if (mpos.x_ < buffer)
        {
            warp = true;
            mpos.x_ += width;
        }

        if (mpos.x_ > buffer + width)
        {
            warp = true;
            mpos.x_ -= width;
        }

        if (mpos.y_ < buffer)
        {
            warp = true;
            mpos.y_ += height;
        }

        if (mpos.y_ > buffer + height)
        {
            warp = true;
            mpos.y_ -= height;
        }

        if (warp)
        {
            SetMousePosition(mpos);
            SDL_FlushEvent(SDL_MOUSEMOTION);
        }
    }
    #else
    if (!window)
        return;

    if (emscriptenExitingPointerLock_)
    {
        // Suppress mouse jump when exiting Pointer Lock
        IntVector2 mousePosition = GetMousePosition();
        mouseMove_ = IntVector2::ZERO;
        lastMousePosition_ = lastVisibleMousePosition_;
        emscriptenExitingPointerLock_ = false;
        return;
    }
    #endif

    // Check for relative mode mouse move
    if (!touchEmulation_ && mouseMode_ != MM_RELATIVE && (graphics_->GetExternalWindow() || (!mouseVisible_ && inputFocus_ && (flags & SDL_WINDOW_MOUSE_FOCUS))))
    {
        IntVector2 mousePosition = GetMousePosition();
        mouseMove_ = mousePosition - lastMousePosition_;
        #ifndef EMSCRIPTEN
        if (graphics_->GetExternalWindow())
            lastMousePosition_ = mousePosition;
        else
        {
            // Recenter the mouse cursor manually after move
            IntVector2 center(graphics_->GetWidth() / 2, graphics_->GetHeight() / 2);
            if (mousePosition != center)
            {
                SetMousePosition(center);
                lastMousePosition_ = center;
            }
        }
        #else
        if (mouseMode_ == MM_ABSOLUTE)
        {
            lastMousePosition_ = mousePosition;
        }
        #endif
        // Send mouse move event if necessary
        if (mouseMove_ != IntVector2::ZERO)
        {
            if (suppressNextMouseMove_)
            {
                mouseMove_ = IntVector2::ZERO;
                suppressNextMouseMove_ = false;
            }
            else
            {
                using namespace MouseMove;

                VariantMap& eventData = GetEventDataMap();
                if (mouseVisible_)
                {
                    eventData[P_X] = mousePosition.x_;
                    eventData[P_Y] = mousePosition.y_;
                }
                eventData[P_DX] = mouseMove_.x_;
                eventData[P_DY] = mouseMove_.y_;
                eventData[P_BUTTONS] = mouseButtonDown_;
                eventData[P_QUALIFIERS] = GetQualifiers();
                SendEvent(E_MOUSEMOVE, eventData);
            }
        }
    }

    #ifndef EMSCRIPTEN
    if (mouseMode_ == MM_RELATIVE)
    {
        IntVector2 mousePosition = GetMousePosition();
        IntVector2 center(graphics_->GetWidth() / 2, graphics_->GetHeight() / 2);
        if (mousePosition != center)
        {
            SetMousePosition(center);
            lastMousePosition_ = center;
        }
    }
    #endif
}

void Input::SetMouseVisible(bool enable, bool suppressEvent)
{
    // In touch emulation mode only enabled mouse is allowed
    if (touchEmulation_)
        enable = true;

    // In mouse mode relative, the mouse should be invisible
    if (mouseMode_ == MM_RELATIVE)
        enable = false;

    // SDL Raspberry Pi "video driver" does not have proper OS mouse support yet, so no-op for now
    #ifndef RPI
    if (enable != mouseVisible_)
    {
        mouseVisible_ = enable;

        if (initialized_)
        {
            // External windows can only support visible mouse cursor
            if (graphics_->GetExternalWindow())
            {
                mouseVisible_ = true;
                if (!suppressEvent)
                    lastMouseVisible_ = true;
                return;
            }

            if (!mouseVisible_ && inputFocus_)
            {
                SDL_ShowCursor(SDL_FALSE);
                #ifndef EMSCRIPTEN
                // Recenter the mouse cursor manually when hiding it to avoid erratic mouse move for one frame
                lastVisibleMousePosition_ = GetMousePosition();
                IntVector2 center(graphics_->GetWidth() / 2, graphics_->GetHeight() / 2);
                SetMousePosition(center);
                lastMousePosition_ = center;
                #else
                lastVisibleMousePosition_ = GetMousePosition();
                lastMousePosition_ = lastVisibleMousePosition_;
                #endif
            }
            else
            {
                SDL_ShowCursor(SDL_TRUE);
                #ifndef EMSCRIPTEN
                if (lastVisibleMousePosition_.x_ != MOUSE_POSITION_OFFSCREEN.x_ && lastVisibleMousePosition_.y_ != MOUSE_POSITION_OFFSCREEN.y_)
                    SetMousePosition(lastVisibleMousePosition_);
                lastMousePosition_ = lastVisibleMousePosition_;
                #endif
            }
        }

        if (!suppressEvent)
        {
            using namespace MouseVisibleChanged;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_VISIBLE] = mouseVisible_;
            SendEvent(E_MOUSEVISIBLECHANGED, eventData);
        }
    }

    // Make sure last mouse visible is valid:
    if (!suppressEvent)
        lastMouseVisible_ = mouseVisible_;
    #endif
}

void Input::ResetMouseVisible()
{
    #ifndef EMSCRIPTEN
    SetMouseVisible(lastMouseVisible_, true);
    #else
    SetMouseVisibleEmscripten(lastMouseVisible_);
    #endif
}

#ifdef EMSCRIPTEN
void Input::SetMouseVisibleEmscripten(bool enable)
{
    if (enable != mouseVisible_)
    {
        mouseVisible_ = enable;
        SDL_ShowCursor(enable ? SDL_TRUE : SDL_FALSE);

        if (!mouseVisible_)
            lastVisibleMousePosition_ = GetMousePosition();

        lastMousePosition_ = lastVisibleMousePosition_;
    }
}

void Input::SetMouseModeEmscripten(MouseMode mode)
{
    mouseMode_ = mode;

    if (mode == MM_RELATIVE)
    {
        SetMouseVisibleEmscripten(false);
    }
    else
    {
        ResetMouseVisible();
    }
    suppressNextMouseMove_ = true;

    VariantMap& eventData = GetEventDataMap();
    eventData[MouseModeChanged::P_MODE] = mode;
    SendEvent(E_MOUSEMODECHANGED, eventData);
}
#endif

void Input::SetMouseGrabbed(bool grab)
{
    mouseGrabbed_ = grab;
}

void Input::SetMouseMode(MouseMode mode)
{
    if (mode != mouseMode_)
    {
        MouseMode previousMode = mouseMode_;
        mouseMode_ = mode;
        suppressNextMouseMove_ = true;
        SDL_Window* window = graphics_->GetImpl()->GetWindow();
        // Handle changing away from previous mode
        if (previousMode == MM_RELATIVE)
        {
            #ifndef EMSCRIPTEN
            /// \todo Use SDL_SetRelativeMouseMode() for MM_RELATIVE mode
            ResetMouseVisible();
            #else
            emscriptenInput_->ExitPointerLock();
            #endif

            SDL_SetWindowGrab(window, SDL_FALSE);
        }
        #ifndef EMSCRIPTEN
        else if (previousMode == MM_WRAP)
        {
            SDL_SetWindowGrab(window, SDL_FALSE);
        }
        #endif

        // Handle changing to new mode
        if (mode == MM_ABSOLUTE)
        {
            #ifndef EMSCRIPTEN
            SetMouseGrabbed(false);
            VariantMap& eventData = GetEventDataMap();
            eventData[MouseModeChanged::P_MODE] = mode;
            SendEvent(E_MOUSEMODECHANGED, eventData);
            #else
            // Deferred mouse mode change to PointerLock callback
            #endif
        }
        else
        {
            SetMouseGrabbed(true);

            if (mode == MM_RELATIVE)
            {
                SDL_SetWindowGrab(window, SDL_TRUE);
                #ifndef EMSCRIPTEN
                SetMouseVisible(false, true);

                VariantMap& eventData = GetEventDataMap();
                eventData[MouseModeChanged::P_MODE] = mode;
                SendEvent(E_MOUSEMODECHANGED, eventData);
                #else
                // Defer mouse mode change to PointerLock callback
                mouseMode_ = previousMode;
                emscriptenInput_->RequestPointerLock();
                #endif

            }
            #ifndef EMSCRIPTEN
            else if (mode == MM_WRAP)
            {
                /// \todo When SDL 2.0.4 is integrated, use SDL_CaptureMouse() and global mouse functions for MM_WRAP mode.
                SDL_SetWindowGrab(window, SDL_TRUE);

                VariantMap& eventData = GetEventDataMap();
                eventData[MouseModeChanged::P_MODE] = mode;
                SendEvent(E_MOUSEMODECHANGED, eventData);
            }
            #endif
        }
    }
}

void Input::SetToggleFullscreen(bool enable)
{
    toggleFullscreen_ = enable;
}

static void PopulateKeyBindingMap(HashMap<String, int>& keyBindingMap)
{
    if (keyBindingMap.Empty())
    {
        keyBindingMap.Insert(MakePair<String, int>("SPACE", KEY_SPACE));
        keyBindingMap.Insert(MakePair<String, int>("LCTRL", KEY_LCTRL));
        keyBindingMap.Insert(MakePair<String, int>("RCTRL", KEY_RCTRL));
        keyBindingMap.Insert(MakePair<String, int>("LSHIFT", KEY_LSHIFT));
        keyBindingMap.Insert(MakePair<String, int>("RSHIFT", KEY_RSHIFT));
        keyBindingMap.Insert(MakePair<String, int>("LALT", KEY_LALT));
        keyBindingMap.Insert(MakePair<String, int>("RALT", KEY_RALT));
        keyBindingMap.Insert(MakePair<String, int>("LGUI", KEY_LGUI));
        keyBindingMap.Insert(MakePair<String, int>("RGUI", KEY_RGUI));
        keyBindingMap.Insert(MakePair<String, int>("TAB", KEY_TAB));
        keyBindingMap.Insert(MakePair<String, int>("RETURN", KEY_RETURN));
        keyBindingMap.Insert(MakePair<String, int>("RETURN2", KEY_RETURN2));
        keyBindingMap.Insert(MakePair<String, int>("ENTER", KEY_KP_ENTER));
        keyBindingMap.Insert(MakePair<String, int>("SELECT", KEY_SELECT));
        keyBindingMap.Insert(MakePair<String, int>("LEFT", KEY_LEFT));
        keyBindingMap.Insert(MakePair<String, int>("RIGHT", KEY_RIGHT));
        keyBindingMap.Insert(MakePair<String, int>("UP", KEY_UP));
        keyBindingMap.Insert(MakePair<String, int>("DOWN", KEY_DOWN));
        keyBindingMap.Insert(MakePair<String, int>("PAGEUP", KEY_PAGEUP));
        keyBindingMap.Insert(MakePair<String, int>("PAGEDOWN", KEY_PAGEDOWN));
        keyBindingMap.Insert(MakePair<String, int>("F1", KEY_F1));
        keyBindingMap.Insert(MakePair<String, int>("F2", KEY_F2));
        keyBindingMap.Insert(MakePair<String, int>("F3", KEY_F3));
        keyBindingMap.Insert(MakePair<String, int>("F4", KEY_F4));
        keyBindingMap.Insert(MakePair<String, int>("F5", KEY_F5));
        keyBindingMap.Insert(MakePair<String, int>("F6", KEY_F6));
        keyBindingMap.Insert(MakePair<String, int>("F7", KEY_F7));
        keyBindingMap.Insert(MakePair<String, int>("F8", KEY_F8));
        keyBindingMap.Insert(MakePair<String, int>("F9", KEY_F9));
        keyBindingMap.Insert(MakePair<String, int>("F10", KEY_F10));
        keyBindingMap.Insert(MakePair<String, int>("F11", KEY_F11));
        keyBindingMap.Insert(MakePair<String, int>("F12", KEY_F12));
    }
}

static void PopulateMouseButtonBindingMap(HashMap<String, int>& mouseButtonBindingMap)
{
    if (mouseButtonBindingMap.Empty())
    {
        mouseButtonBindingMap.Insert(MakePair<String, int>("LEFT", SDL_BUTTON_LEFT));
        mouseButtonBindingMap.Insert(MakePair<String, int>("MIDDLE", SDL_BUTTON_MIDDLE));
        mouseButtonBindingMap.Insert(MakePair<String, int>("RIGHT", SDL_BUTTON_RIGHT));
        mouseButtonBindingMap.Insert(MakePair<String, int>("X1", SDL_BUTTON_X1));
        mouseButtonBindingMap.Insert(MakePair<String, int>("X2", SDL_BUTTON_X2));
    }
}

int Input::AddScreenJoystick(XMLFile* layoutFile, XMLFile* styleFile)
{
    static HashMap<String, int> keyBindingMap;
    static HashMap<String, int> mouseButtonBindingMap;

    if (!graphics_)
    {
        LOGWARNING("Cannot add screen joystick in headless mode");
        return -1;
    }

    // If layout file is not given, use the default screen joystick layout
    if (!layoutFile)
    {
        ResourceCache* cache = GetSubsystem<ResourceCache>();
        layoutFile = cache->GetResource<XMLFile>("UI/ScreenJoystick.xml");
        if (!layoutFile)    // Error is already logged
            return -1;
    }

    UI* ui = GetSubsystem<UI>();
    SharedPtr<UIElement> screenJoystick = ui->LoadLayout(layoutFile, styleFile);
    if (!screenJoystick)     // Error is already logged
        return -1;

    screenJoystick->SetSize(ui->GetRoot()->GetSize());
    ui->GetRoot()->AddChild(screenJoystick);

    // Get an unused ID for the screen joystick
    /// \todo After a real joystick has been plugged in 1073741824 times, the ranges will overlap
    SDL_JoystickID joystickID = SCREEN_JOYSTICK_START_ID;
    while (joysticks_.Contains(joystickID))
        ++joystickID;

    JoystickState& state = joysticks_[joystickID];
    state.joystickID_ = joystickID;
    state.name_ = screenJoystick->GetName();
    state.screenJoystick_ = screenJoystick;

    unsigned numButtons = 0;
    unsigned numAxes = 0;
    unsigned numHats = 0;
    const Vector<SharedPtr<UIElement> >& children = state.screenJoystick_->GetChildren();
    for (Vector<SharedPtr<UIElement> >::ConstIterator iter = children.Begin(); iter != children.End(); ++iter)
    {
        UIElement* element = iter->Get();
        String name = element->GetName();
        if (name.StartsWith("Button"))
        {
            ++numButtons;

            // Check whether the button has key binding
            Text* text = dynamic_cast<Text*>(element->GetChild("KeyBinding", false));
            if (text)
            {
                text->SetVisible(false);
                const String& key = text->GetText();
                int keyBinding;
                if (key.Length() == 1)
                    keyBinding = key[0];
                else
                {
                    PopulateKeyBindingMap(keyBindingMap);

                    HashMap<String, int>::Iterator i = keyBindingMap.Find(key);
                    if (i != keyBindingMap.End())
                        keyBinding = i->second_;
                    else
                    {
                        LOGERRORF("Unsupported key binding: %s", key.CString());
                        keyBinding = M_MAX_INT;
                    }
                }

                if (keyBinding != M_MAX_INT)
                    element->SetVar(VAR_BUTTON_KEY_BINDING, keyBinding);
            }

            // Check whether the button has mouse button binding
            text = dynamic_cast<Text*>(element->GetChild("MouseButtonBinding", false));
            if (text)
            {
                text->SetVisible(false);
                const String& mouseButton = text->GetText();
                PopulateMouseButtonBindingMap(mouseButtonBindingMap);

                HashMap<String, int>::Iterator i = mouseButtonBindingMap.Find(mouseButton);
                if (i != mouseButtonBindingMap.End())
                    element->SetVar(VAR_BUTTON_MOUSE_BUTTON_BINDING, i->second_);
                else
                    LOGERRORF("Unsupported mouse button binding: %s", mouseButton.CString());
            }
        }
        else if (name.StartsWith("Axis"))
        {
            ++numAxes;

            ///\todo Axis emulation for screen joystick is not fully supported yet.
            LOGWARNING("Axis emulation for screen joystick is not fully supported yet");
        }
        else if (name.StartsWith("Hat"))
        {
            ++numHats;

            Text* text = dynamic_cast<Text*>(element->GetChild("KeyBinding", false));
            if (text)
            {
                text->SetVisible(false);
                String keyBinding = text->GetText();
                if (keyBinding.Contains(' '))   // e.g.: "UP DOWN LEFT RIGHT"
                {
                    // Attempt to split the text using ' ' as separator
                    Vector<String>keyBindings(keyBinding.Split(' '));
                    String mappedKeyBinding;
                    if (keyBindings.Size() == 4)
                    {
                        PopulateKeyBindingMap(keyBindingMap);

                        for (unsigned j = 0; j < 4; ++j)
                        {
                            if (keyBindings[j].Length() == 1)
                                mappedKeyBinding.Append(keyBindings[j][0]);
                            else
                            {
                                HashMap<String, int>::Iterator i = keyBindingMap.Find(keyBindings[j]);
                                if (i != keyBindingMap.End())
                                    mappedKeyBinding.Append(i->second_);
                                else
                                    break;
                            }
                        }
                    }
                    if (mappedKeyBinding.Length() != 4)
                    {
                        LOGERRORF("%s has invalid key binding %s, fallback to WSAD", name.CString(), keyBinding.CString());
                        keyBinding = "WSAD";
                    }
                    else
                        keyBinding = mappedKeyBinding;
                }
                else if (keyBinding.Length() != 4)
                {
                    LOGERRORF("%s has invalid key binding %s, fallback to WSAD", name.CString(), keyBinding.CString());
                    keyBinding = "WSAD";
                }

                element->SetVar(VAR_BUTTON_KEY_BINDING, keyBinding);
            }
        }

        element->SetVar(VAR_SCREEN_JOYSTICK_ID, joystickID);
    }

    // Make sure all the children are non-focusable so they do not mistakenly to be considered as active UI input controls by application
    PODVector<UIElement*> allChildren;
    state.screenJoystick_->GetChildren(allChildren, true);
    for (PODVector<UIElement*>::Iterator iter = allChildren.Begin(); iter != allChildren.End(); ++iter)
        (*iter)->SetFocusMode(FM_NOTFOCUSABLE);

    state.Initialize(numButtons, numAxes, numHats);

    // There could be potentially more than one screen joystick, however they all will be handled by a same handler method
    // So there is no harm to replace the old handler with the new handler in each call to SubscribeToEvent()
    SubscribeToEvent(E_TOUCHBEGIN, HANDLER(Input, HandleScreenJoystickTouch));
    SubscribeToEvent(E_TOUCHMOVE, HANDLER(Input, HandleScreenJoystickTouch));
    SubscribeToEvent(E_TOUCHEND, HANDLER(Input, HandleScreenJoystickTouch));

    return joystickID;
}

bool Input::RemoveScreenJoystick(SDL_JoystickID id)
{
    if (!joysticks_.Contains(id))
    {
        LOGERRORF("Failed to remove non-existing screen joystick ID #%d", id);
        return false;
    }

    JoystickState& state = joysticks_[id];
    if (!state.screenJoystick_)
    {
        LOGERRORF("Failed to remove joystick with ID #%d which is not a screen joystick", id);
        return false;
    }

    state.screenJoystick_->Remove();
    joysticks_.Erase(id);

    return true;
}

void Input::SetScreenJoystickVisible(SDL_JoystickID id, bool enable)
{
    if (joysticks_.Contains(id))
    {
        JoystickState& state = joysticks_[id];

        if (state.screenJoystick_)
            state.screenJoystick_->SetVisible(enable);
    }
}

void Input::SetScreenKeyboardVisible(bool enable)
{
    if (!graphics_)
        return;

    if (enable != IsScreenKeyboardVisible())
    {
        if (enable)
            SDL_StartTextInput();
        else
            SDL_StopTextInput();
    }
}

void Input::SetTouchEmulation(bool enable)
{
#if !defined(ANDROID) && !defined(IOS)
    if (enable != touchEmulation_)
    {
        if (enable)
        {
            // Touch emulation needs the mouse visible
            if (!mouseVisible_)
                SetMouseVisible(true);

            // Add a virtual touch device the first time we are enabling emulated touch
            if (!SDL_GetNumTouchDevices())
                SDL_AddTouch(0, "Emulated Touch");
        }
        else
            ResetTouches();

        touchEmulation_ = enable;
    }
#endif
}

bool Input::RecordGesture()
{
    // If have no touch devices, fail
    if (!SDL_GetNumTouchDevices())
    {
        LOGERROR("Can not record gesture: no touch devices");
        return false;
    }

    return SDL_RecordGesture(-1) != 0;
}

bool Input::SaveGestures(Serializer& dest)
{
    RWOpsWrapper<Serializer> wrapper(dest);
    return SDL_SaveAllDollarTemplates(wrapper.GetRWOps()) != 0;
}

bool Input::SaveGesture(Serializer& dest, unsigned gestureID)
{
    RWOpsWrapper<Serializer> wrapper(dest);
    return SDL_SaveDollarTemplate(gestureID, wrapper.GetRWOps()) != 0;
}

unsigned Input::LoadGestures(Deserializer& source)
{
    // If have no touch devices, fail
    if (!SDL_GetNumTouchDevices())
    {
        LOGERROR("Can not load gestures: no touch devices");
        return 0;
    }

    RWOpsWrapper<Deserializer> wrapper(source);
    return SDL_LoadDollarTemplates(-1, wrapper.GetRWOps());
}


bool Input::RemoveGesture(unsigned gestureID)
{
#if defined(EMSCRIPTEN)
    return false;
#else
    return SDL_RemoveDollarTemplate(gestureID) != 0;
#endif
}

void Input::RemoveAllGestures()
{
#if !defined(EMSCRIPTEN)
    SDL_RemoveAllDollarTemplates();
#endif
}

SDL_JoystickID Input::OpenJoystick(unsigned index)
{
    SDL_Joystick* joystick = SDL_JoystickOpen(index);
    if (!joystick)
    {
        LOGERRORF("Cannot open joystick #%d", index);
        return -1;
    }

    // Create joystick state for the new joystick
    int joystickID = SDL_JoystickInstanceID(joystick);
    JoystickState& state = joysticks_[joystickID];
    state.joystick_ = joystick;
    state.joystickID_ = joystickID;
    state.name_ = SDL_JoystickName(joystick);
    if (SDL_IsGameController(index))
       state.controller_ = SDL_GameControllerOpen(index);

    unsigned numButtons = SDL_JoystickNumButtons(joystick);
    unsigned numAxes = SDL_JoystickNumAxes(joystick);
    unsigned numHats = SDL_JoystickNumHats(joystick);

    // When the joystick is a controller, make sure there's enough axes & buttons for the standard controller mappings
    if (state.controller_)
    {
        if (numButtons < SDL_CONTROLLER_BUTTON_MAX)
            numButtons = SDL_CONTROLLER_BUTTON_MAX;
        if (numAxes < SDL_CONTROLLER_AXIS_MAX)
            numAxes = SDL_CONTROLLER_AXIS_MAX;
    }

    state.Initialize(numButtons, numAxes, numHats);

    return joystickID;
}

int Input::GetKeyFromName(const String& name) const
{
    return SDL_GetKeyFromName(name.CString());
}

int Input::GetKeyFromScancode(int scancode) const
{
    return SDL_GetKeyFromScancode((SDL_Scancode)scancode);
}

String Input::GetKeyName(int key) const
{
    return String(SDL_GetKeyName(key));
}

int Input::GetScancodeFromKey(int key) const
{
    return SDL_GetScancodeFromKey(key);
}

int Input::GetScancodeFromName(const String& name) const
{
    return SDL_GetScancodeFromName(name.CString());
}

String Input::GetScancodeName(int scancode) const
{
    return SDL_GetScancodeName((SDL_Scancode)scancode);
}

bool Input::GetKeyDown(int key) const
{
    return keyDown_.Contains(SDL_toupper(key));
}

bool Input::GetKeyPress(int key) const
{
    return keyPress_.Contains(SDL_toupper(key));
}

bool Input::GetScancodeDown(int scancode) const
{
    return scancodeDown_.Contains(scancode);
}

bool Input::GetScancodePress(int scancode) const
{
    return scancodePress_.Contains(scancode);
}

bool Input::GetMouseButtonDown(int button) const
{
    return (mouseButtonDown_ & button) != 0;
}

bool Input::GetMouseButtonPress(int button) const
{
    return (mouseButtonPress_ & button) != 0;
}

bool Input::GetQualifierDown(int qualifier) const
{
    if (qualifier == QUAL_SHIFT)
        return GetKeyDown(KEY_LSHIFT) || GetKeyDown(KEY_RSHIFT);
    if (qualifier == QUAL_CTRL)
        return GetKeyDown(KEY_LCTRL) || GetKeyDown(KEY_RCTRL);
    if (qualifier == QUAL_ALT)
        return GetKeyDown(KEY_LALT) || GetKeyDown(KEY_RALT);

    return false;
}

bool Input::GetQualifierPress(int qualifier) const
{
    if (qualifier == QUAL_SHIFT)
        return GetKeyPress(KEY_LSHIFT) || GetKeyPress(KEY_RSHIFT);
    if (qualifier == QUAL_CTRL)
        return GetKeyPress(KEY_LCTRL) || GetKeyPress(KEY_RCTRL);
    if (qualifier == QUAL_ALT)
        return GetKeyPress(KEY_LALT) || GetKeyPress(KEY_RALT);

    return false;
}

int Input::GetQualifiers() const
{
    int ret = 0;
    if (GetQualifierDown(QUAL_SHIFT))
        ret |= QUAL_SHIFT;
    if (GetQualifierDown(QUAL_CTRL))
        ret |= QUAL_CTRL;
    if (GetQualifierDown(QUAL_ALT))
        ret |= QUAL_ALT;

    return ret;
}

IntVector2 Input::GetMousePosition() const
{
    IntVector2 ret = IntVector2::ZERO;

    if (!initialized_)
        return ret;

    SDL_GetMouseState(&ret.x_, &ret.y_);

    return ret;
}

TouchState* Input::GetTouch(unsigned index) const
{
    if (index >= touches_.Size())
        return 0;

    HashMap<int, TouchState>::ConstIterator i = touches_.Begin();
    while (index--)
        ++i;

    return const_cast<TouchState*>(&i->second_);
}

JoystickState* Input::GetJoystickByIndex(unsigned index)
{
    unsigned compare = 0;
    for (HashMap<SDL_JoystickID, JoystickState>::Iterator i = joysticks_.Begin(); i != joysticks_.End(); ++i)
    {
        if (compare++ == index)
            return &(i->second_);
    }

    return 0;
}

JoystickState* Input::GetJoystick(SDL_JoystickID id)
{
    HashMap<SDL_JoystickID, JoystickState>::Iterator i = joysticks_.Find(id);
    return i != joysticks_.End() ? &(i->second_) : 0;
}

bool Input::IsScreenJoystickVisible(SDL_JoystickID id) const
{
    HashMap<SDL_JoystickID, JoystickState>::ConstIterator i = joysticks_.Find(id);
    return i != joysticks_.End() && i->second_.screenJoystick_ && i->second_.screenJoystick_->IsVisible();
}

bool Input::GetScreenKeyboardSupport() const
{
    return graphics_ ? SDL_HasScreenKeyboardSupport() != 0 : false;
}

bool Input::IsScreenKeyboardVisible() const
{
    if (graphics_)
    {
        SDL_Window* window = graphics_->GetImpl()->GetWindow();
        return SDL_IsScreenKeyboardShown(window) != SDL_FALSE;
    }
    else
        return false;
}

bool Input::IsMinimized() const
{
    // Return minimized state also when unfocused in fullscreen
    if (!inputFocus_ && graphics_ && graphics_->GetFullscreen())
        return true;
    else
        return minimized_;
}

void Input::Initialize()
{
    Graphics* graphics = GetSubsystem<Graphics>();
    if (!graphics || !graphics->IsInitialized())
        return;

    graphics_ = graphics;

    // In external window mode only visible mouse is supported
    if (graphics_->GetExternalWindow())
        mouseVisible_ = true;

    // Set the initial activation
    initialized_ = true;
#ifndef EMSCRIPTEN
    focusedThisFrame_ = true;
#else
    // Note: Page visibility and focus are slightly different, however we can't query last focus with Emscripten (1.29.0)
    if (emscriptenInput_->IsVisible())
        GainFocus();
    else
        LoseFocus();
#endif

    ResetJoysticks();
    ResetState();

    SubscribeToEvent(E_BEGINFRAME, HANDLER(Input, HandleBeginFrame));

    LOGINFO("Initialized input");
}

void Input::ResetJoysticks()
{
    joysticks_.Clear();

    // Open each detected joystick automatically on startup
    int size = SDL_NumJoysticks();
    for (int i = 0; i < size; ++i)
        OpenJoystick(i);
}

void Input::GainFocus()
{
    ResetState();

    inputFocus_ = true;
    focusedThisFrame_ = false;

    // Restore mouse mode
    MouseMode mm = mouseMode_;
    mouseMode_ = MM_ABSOLUTE;
    SetMouseMode(mm);

    // Re-establish mouse cursor hiding as necessary
    if (!mouseVisible_)
    {
        SDL_ShowCursor(SDL_FALSE);
        suppressNextMouseMove_ = true;
    }
    else
        lastMousePosition_ = GetMousePosition();

    SendInputFocusEvent();
}

void Input::LoseFocus()
{
    ResetState();

    inputFocus_ = false;
    focusedThisFrame_ = false;

    MouseMode mm = mouseMode_;

    // Show the mouse cursor when inactive
    SDL_ShowCursor(SDL_TRUE);

    // Change mouse mode -- removing any cursor grabs, etc.
    SetMouseMode(MM_ABSOLUTE);

    // Restore flags to reflect correct mouse state.
    mouseMode_ = mm;

    SendInputFocusEvent();
}

void Input::ResetState()
{
    keyDown_.Clear();
    keyPress_.Clear();
    scancodeDown_.Clear();
    scancodePress_.Clear();

    /// \todo Check if resetting joystick state on input focus loss is even necessary
    for (HashMap<SDL_JoystickID, JoystickState>::Iterator i = joysticks_.Begin(); i != joysticks_.End(); ++i)
        i->second_.Reset();

    ResetTouches();

    // Use SetMouseButton() to reset the state so that mouse events will be sent properly
    SetMouseButton(MOUSEB_LEFT, false);
    SetMouseButton(MOUSEB_RIGHT, false);
    SetMouseButton(MOUSEB_MIDDLE, false);

    mouseMove_ = IntVector2::ZERO;
    mouseMoveWheel_ = 0;
    mouseButtonPress_ = 0;
}

void Input::ResetTouches()
{
    for (HashMap<int, TouchState>::Iterator i = touches_.Begin(); i != touches_.End(); ++i)
    {
        TouchState& state = i->second_;

        using namespace TouchEnd;

        VariantMap& eventData = GetEventDataMap();
        eventData[P_TOUCHID] = state.touchID_;
        eventData[P_X] = state.position_.x_;
        eventData[P_Y] = state.position_.y_;
        SendEvent(E_TOUCHEND, eventData);
    }

    touches_.Clear();
    touchIDMap_.Clear();
    availableTouchIDs_.Clear();
    for (int i = 0; i < TOUCHID_MAX; i++)
        availableTouchIDs_.Push(i);

}

unsigned Input::GetTouchIndexFromID(int touchID)
{
    HashMap<int, int>::ConstIterator i = touchIDMap_.Find(touchID);
    if (i != touchIDMap_.End())
    {
        return i->second_;
    }

    int index = PopTouchIndex();
    touchIDMap_[touchID] = index;
    return index;
}

unsigned Input::PopTouchIndex()
{
    if (availableTouchIDs_.Empty())
        return 0;

    unsigned index = availableTouchIDs_.Front();
    availableTouchIDs_.PopFront();
    return index;
}

void Input::PushTouchIndex(int touchID)
{
    HashMap<int, int>::ConstIterator ci = touchIDMap_.Find(touchID);
    if (ci == touchIDMap_.End())
        return;

    int index = touchIDMap_[touchID];
    touchIDMap_.Erase(touchID);

    // Sorted insertion
    bool inserted = false;
    for (List<int>::Iterator i = availableTouchIDs_.Begin(); i != availableTouchIDs_.End(); ++i)
    {
        if (*i == index)
        {
            // This condition can occur when TOUCHID_MAX is reached.
            inserted = true;
            break;
        }

        if (*i > index)
        {
            availableTouchIDs_.Insert(i, index);
            inserted = true;
            break;
        }
    }

    // If empty, or the lowest value then insert at end.
    if (!inserted)
        availableTouchIDs_.Push(index);
}

void Input::SendInputFocusEvent()
{
    using namespace InputFocus;

    VariantMap& eventData = GetEventDataMap();
    eventData[P_FOCUS] = HasFocus();
    eventData[P_MINIMIZED] = IsMinimized();
    SendEvent(E_INPUTFOCUS, eventData);
}

void Input::SetMouseButton(int button, bool newState)
{
#ifdef REQUIRE_CLICK_TO_FOCUS
    if (!mouseVisible_ && !graphics_->GetFullscreen())
    {
        if (!inputFocus_ && newState && button == MOUSEB_LEFT)
            focusedThisFrame_ = true;
    }
#endif

#ifdef EMSCRIPTEN
    if (emscriptenEnteredPointerLock_)
    {
        // Suppress mouse jump on initial Pointer Lock
        IntVector2 mousePosition = GetMousePosition();
        lastMousePosition_ = mousePosition;
        mouseMove_ = IntVector2::ZERO;
        suppressNextMouseMove_ = true;
        emscriptenEnteredPointerLock_ = false;
    }
#endif

    // If we do not have focus yet, do not react to the mouse button down
    if (!graphics_->GetExternalWindow() && newState && !inputFocus_)
        return;

    if (newState)
    {
        if (!(mouseButtonDown_ & button))
            mouseButtonPress_ |= button;

        mouseButtonDown_ |= button;
    }
    else
    {
        if (!(mouseButtonDown_ & button))
            return;

        mouseButtonDown_ &= ~button;
    }

    using namespace MouseButtonDown;

    VariantMap& eventData = GetEventDataMap();
    eventData[P_BUTTON] = button;
    eventData[P_BUTTONS] = mouseButtonDown_;
    eventData[P_QUALIFIERS] = GetQualifiers();
    SendEvent(newState ? E_MOUSEBUTTONDOWN : E_MOUSEBUTTONUP, eventData);
}

void Input::SetKey(int key, int scancode, unsigned raw, bool newState)
{
    // If we do not have focus yet, do not react to the key down
    if (!graphics_->GetExternalWindow() && newState && !inputFocus_)
        return;

    bool repeat = false;

    if (newState)
    {
        scancodeDown_.Insert(scancode);
        scancodePress_.Insert(scancode);

        if (!keyDown_.Contains(key))
        {
            keyDown_.Insert(key);
            keyPress_.Insert(key);
        }
        else
            repeat = true;
    }
    else
    {
        scancodeDown_.Erase(scancode);

        if (!keyDown_.Erase(key))
            return;
    }

    using namespace KeyDown;

    VariantMap& eventData = GetEventDataMap();
    eventData[P_KEY] = key;
    eventData[P_SCANCODE] = scancode;
    eventData[P_RAW] = raw;
    eventData[P_BUTTONS] = mouseButtonDown_;
    eventData[P_QUALIFIERS] = GetQualifiers();
    if (newState)
        eventData[P_REPEAT] = repeat;
    SendEvent(newState ? E_KEYDOWN : E_KEYUP, eventData);

    if ((key == KEY_RETURN || key == KEY_RETURN2 || key == KEY_KP_ENTER) && newState && !repeat && toggleFullscreen_ &&
        (GetKeyDown(KEY_LALT) || GetKeyDown(KEY_RALT)))
        graphics_->ToggleFullscreen();
}

void Input::SetMouseWheel(int delta)
{
    // If we do not have focus yet, do not react to the wheel
    if (!graphics_->GetExternalWindow() && !inputFocus_)
        return;

    if (delta)
    {
        mouseMoveWheel_ += delta;

        using namespace MouseWheel;

        VariantMap& eventData = GetEventDataMap();
        eventData[P_WHEEL] = delta;
        eventData[P_BUTTONS] = mouseButtonDown_;
        eventData[P_QUALIFIERS] = GetQualifiers();
        SendEvent(E_MOUSEWHEEL, eventData);
    }
}

void Input::SetMousePosition(const IntVector2& position)
{
    if (!graphics_)
        return;

    SDL_WarpMouseInWindow(graphics_->GetImpl()->GetWindow(), position.x_, position.y_);
}

void Input::HandleSDLEvent(void* sdlEvent)
{
    SDL_Event& evt = *static_cast<SDL_Event*>(sdlEvent);

    switch (evt.type)
    {
    case SDL_KEYDOWN:
        // Convert to uppercase to match Win32 virtual key codes
#if defined (EMSCRIPTEN)
        SetKey(ConvertSDLKeyCode(evt.key.keysym.sym, evt.key.keysym.scancode), evt.key.keysym.scancode, 0, true);
#else
        SetKey(ConvertSDLKeyCode(evt.key.keysym.sym, evt.key.keysym.scancode), evt.key.keysym.scancode, evt.key.keysym.raw, true);
#endif
        break;

    case SDL_KEYUP:
#if defined(EMSCRIPTEN)
        SetKey(ConvertSDLKeyCode(evt.key.keysym.sym, evt.key.keysym.scancode), evt.key.keysym.scancode, 0, false);
#else
        SetKey(ConvertSDLKeyCode(evt.key.keysym.sym, evt.key.keysym.scancode), evt.key.keysym.scancode, evt.key.keysym.raw, false);
#endif
        break;

    case SDL_TEXTINPUT:
        {
            textInput_ = &evt.text.text[0];
            unsigned unicode = textInput_.AtUTF8(0);
            if (unicode)
            {
                using namespace TextInput;

                VariantMap textInputEventData;

                textInputEventData[P_TEXT] = textInput_;
                textInputEventData[P_BUTTONS] = mouseButtonDown_;
                textInputEventData[P_QUALIFIERS] = GetQualifiers();
                SendEvent(E_TEXTINPUT, textInputEventData);
            }
        }
        break;

    case SDL_MOUSEBUTTONDOWN:
        if (!touchEmulation_)
            SetMouseButton(1 << (evt.button.button - 1), true);
        else
        {
            int x, y;
            SDL_GetMouseState(&x, &y);

            SDL_Event event;
            event.type = SDL_FINGERDOWN;
            event.tfinger.touchId = 0;
            event.tfinger.fingerId = evt.button.button - 1;
            event.tfinger.pressure = 1.0f;
            event.tfinger.x = (float)x / (float)graphics_->GetWidth();
            event.tfinger.y = (float)y / (float)graphics_->GetHeight();
            event.tfinger.dx = 0;
            event.tfinger.dy = 0;
            SDL_PushEvent(&event);
        }
        break;

    case SDL_MOUSEBUTTONUP:
        if (!touchEmulation_)
            SetMouseButton(1 << (evt.button.button - 1), false);
        else
        {
            int x, y;
            SDL_GetMouseState(&x, &y);

            SDL_Event event;
            event.type = SDL_FINGERUP;
            event.tfinger.touchId = 0;
            event.tfinger.fingerId = evt.button.button - 1;
            event.tfinger.pressure = 0.0f;
            event.tfinger.x = (float)x / (float)graphics_->GetWidth();
            event.tfinger.y = (float)y / (float)graphics_->GetHeight();
            event.tfinger.dx = 0;
            event.tfinger.dy = 0;
            SDL_PushEvent(&event);
        }
        break;

    case SDL_MOUSEMOTION:
        if ((mouseVisible_ || mouseMode_ == MM_RELATIVE) && !touchEmulation_)
        {
            mouseMove_.x_ += evt.motion.xrel;
            mouseMove_.y_ += evt.motion.yrel;

            using namespace MouseMove;

            VariantMap& eventData = GetEventDataMap();
            if (mouseVisible_)
            {
                eventData[P_X] = evt.motion.x;
                eventData[P_Y] = evt.motion.y;
            }
            eventData[P_DX] = evt.motion.xrel;
            eventData[P_DY] = evt.motion.yrel;
            eventData[P_BUTTONS] = mouseButtonDown_;
            eventData[P_QUALIFIERS] = GetQualifiers();
            SendEvent(E_MOUSEMOVE, eventData);
        }
        // Only the left mouse button "finger" moves along with the mouse movement
        else if (touchEmulation_ && touches_.Contains(0))
        {
            int x, y;
            SDL_GetMouseState(&x, &y);

            SDL_Event event;
            event.type = SDL_FINGERMOTION;
            event.tfinger.touchId = 0;
            event.tfinger.fingerId = 0;
            event.tfinger.pressure = 1.0f;
            event.tfinger.x = (float)x / (float)graphics_->GetWidth();
            event.tfinger.y = (float)y / (float)graphics_->GetHeight();
            event.tfinger.dx = (float)evt.motion.xrel / (float)graphics_->GetWidth();
            event.tfinger.dy = (float)evt.motion.yrel / (float)graphics_->GetHeight();
            SDL_PushEvent(&event);
        }
        break;

    case SDL_MOUSEWHEEL:
        if (!touchEmulation_)
            SetMouseWheel(evt.wheel.y);
        break;

    case SDL_FINGERDOWN:
        if (evt.tfinger.touchId != SDL_TOUCH_MOUSEID)
        {
            int touchID = GetTouchIndexFromID(evt.tfinger.fingerId & 0x7ffffff);
            TouchState& state = touches_[touchID];
            state.touchID_ = touchID;
            #ifndef EMSCRIPTEN
            state.lastPosition_ = state.position_ = IntVector2((int)(evt.tfinger.x * graphics_->GetWidth()),
                (int)(evt.tfinger.y * graphics_->GetHeight()));
            #else
            state.position_ = IntVector2((int)(evt.tfinger.x), (int)(evt.tfinger.y));
            #endif
            state.delta_ = IntVector2::ZERO;
            state.pressure_ = evt.tfinger.pressure;

            using namespace TouchBegin;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_TOUCHID] = touchID;
            eventData[P_X] = state.position_.x_;
            eventData[P_Y] = state.position_.y_;
            eventData[P_PRESSURE] = state.pressure_;
            SendEvent(E_TOUCHBEGIN, eventData);
        }
        break;

    case SDL_FINGERUP:
        if (evt.tfinger.touchId != SDL_TOUCH_MOUSEID)
        {
            int touchID = GetTouchIndexFromID(evt.tfinger.fingerId & 0x7ffffff);
            TouchState& state = touches_[touchID];

            using namespace TouchEnd;

            VariantMap& eventData = GetEventDataMap();
            // Do not trust the position in the finger up event. Instead use the last position stored in the
            // touch structure
            eventData[P_TOUCHID] = touchID;
            eventData[P_X] = state.position_.x_;
            eventData[P_Y] = state.position_.y_;
            SendEvent(E_TOUCHEND, eventData);

            // Add touch index back to list of available touch Ids
            PushTouchIndex(evt.tfinger.fingerId & 0x7ffffff);

            touches_.Erase(touchID);
        }
        break;

    case SDL_FINGERMOTION:
        if (evt.tfinger.touchId != SDL_TOUCH_MOUSEID)
        {
            int touchID = GetTouchIndexFromID(evt.tfinger.fingerId & 0x7ffffff);
            // We don't want this event to create a new touches_ event if it doesn't exist (touchEmulation)
            if (touchEmulation_ && !touches_.Contains(touchID))
                break;
            TouchState& state = touches_[touchID];
            state.touchID_ = touchID;
            #ifndef EMSCRIPTEN
            state.position_ = IntVector2((int)(evt.tfinger.x * graphics_->GetWidth()),
                (int)(evt.tfinger.y * graphics_->GetHeight()));
            #else
            state.position_ = IntVector2((int)(evt.tfinger.x), (int)(evt.tfinger.y));
            #endif
            state.delta_ = state.position_ - state.lastPosition_;
            state.pressure_ = evt.tfinger.pressure;

            using namespace TouchMove;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_TOUCHID] = touchID;
            eventData[P_X] = state.position_.x_;
            eventData[P_Y] = state.position_.y_;
            #ifndef EMSCRIPTEN
            eventData[P_DX] = (int)(evt.tfinger.dx * graphics_->GetWidth());
            eventData[P_DY] = (int)(evt.tfinger.dy * graphics_->GetHeight());
            #else
            eventData[P_DX] = (int)(evt.tfinger.dx);
            eventData[P_DY] = (int)(evt.tfinger.dy);
            #endif
            eventData[P_PRESSURE] = state.pressure_;
            SendEvent(E_TOUCHMOVE, eventData);
        }
        break;

    case SDL_DOLLARRECORD:
        {
            using namespace GestureRecorded;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_GESTUREID] = (int)evt.dgesture.gestureId;
            SendEvent(E_GESTURERECORDED, eventData);
        }
        break;

    case SDL_DOLLARGESTURE:
        {
            using namespace GestureInput;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_GESTUREID] = (int)evt.dgesture.gestureId;
            eventData[P_CENTERX] = (int)(evt.dgesture.x * graphics_->GetWidth());
            eventData[P_CENTERY] = (int)(evt.dgesture.y * graphics_->GetHeight());
            eventData[P_NUMFINGERS] = (int)evt.dgesture.numFingers;
            eventData[P_ERROR] = evt.dgesture.error;
            SendEvent(E_GESTUREINPUT, eventData);
        }
        break;

    case SDL_MULTIGESTURE:
        {
            using namespace MultiGesture;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_CENTERX] = (int)(evt.mgesture.x * graphics_->GetWidth());
            eventData[P_CENTERY] = (int)(evt.mgesture.y * graphics_->GetHeight());
            eventData[P_NUMFINGERS] = (int)evt.mgesture.numFingers;
            eventData[P_DTHETA] = M_RADTODEG * evt.mgesture.dTheta;
            eventData[P_DDIST] = evt.mgesture.dDist;
            SendEvent(E_MULTIGESTURE, eventData);
        }
        break;

    case SDL_JOYDEVICEADDED:
        {
            using namespace JoystickConnected;

            SDL_JoystickID joystickID = OpenJoystick(evt.jdevice.which);

            VariantMap& eventData = GetEventDataMap();
            eventData[P_JOYSTICKID] = joystickID;
            SendEvent(E_JOYSTICKCONNECTED, eventData);
        }
        break;

    case SDL_JOYDEVICEREMOVED:
        {
            using namespace JoystickDisconnected;

            joysticks_.Erase(evt.jdevice.which);

            VariantMap& eventData = GetEventDataMap();
            eventData[P_JOYSTICKID] = evt.jdevice.which;
            SendEvent(E_JOYSTICKDISCONNECTED, eventData);
        }
        break;

    case SDL_JOYBUTTONDOWN:
        {
            using namespace JoystickButtonDown;

            unsigned button = evt.jbutton.button;
            SDL_JoystickID joystickID = evt.jbutton.which;
            JoystickState& state = joysticks_[joystickID];

            // Skip ordinary joystick event for a controller
            if (!state.controller_)
            {
                VariantMap& eventData = GetEventDataMap();
                eventData[P_JOYSTICKID] = joystickID;
                eventData[P_BUTTON] = button;

                if (button < state.buttons_.Size())
                {
                    state.buttons_[button] = true;
                    state.buttonPress_[button] = true;
                    SendEvent(E_JOYSTICKBUTTONDOWN, eventData);
                }
            }
        }
        break;

    case SDL_JOYBUTTONUP:
        {
            using namespace JoystickButtonUp;

            unsigned button = evt.jbutton.button;
            SDL_JoystickID joystickID = evt.jbutton.which;
            JoystickState& state = joysticks_[joystickID];

            if (!state.controller_)
            {
                VariantMap& eventData = GetEventDataMap();
                eventData[P_JOYSTICKID] = joystickID;
                eventData[P_BUTTON] = button;

                if (button < state.buttons_.Size())
                {
                    if (!state.controller_)
                        state.buttons_[button] = false;
                    SendEvent(E_JOYSTICKBUTTONUP, eventData);
                }
            }
        }
        break;

    case SDL_JOYAXISMOTION:
        {
            using namespace JoystickAxisMove;

            SDL_JoystickID joystickID = evt.jaxis.which;
            JoystickState& state = joysticks_[joystickID];

            if (!state.controller_)
            {
                VariantMap& eventData = GetEventDataMap();
                eventData[P_JOYSTICKID] = joystickID;
                eventData[P_AXIS] = evt.jaxis.axis;
                eventData[P_POSITION] = Clamp((float)evt.jaxis.value / 32767.0f, -1.0f, 1.0f);

                if (evt.jaxis.axis < state.axes_.Size())
                {
                    // If the joystick is a controller, only use the controller axis mappings
                    // (we'll also get the controller event)
                    if (!state.controller_)
                        state.axes_[evt.jaxis.axis] = eventData[P_POSITION].GetFloat();
                    SendEvent(E_JOYSTICKAXISMOVE, eventData);
                }
            }
        }
        break;

    case SDL_JOYHATMOTION:
        {
            using namespace JoystickHatMove;

            SDL_JoystickID joystickID = evt.jaxis.which;
            JoystickState& state = joysticks_[joystickID];

            VariantMap& eventData = GetEventDataMap();
            eventData[P_JOYSTICKID] = joystickID;
            eventData[P_HAT] = evt.jhat.hat;
            eventData[P_POSITION] = evt.jhat.value;

            if (evt.jhat.hat < state.hats_.Size())
            {
                state.hats_[evt.jhat.hat] = evt.jhat.value;
                SendEvent(E_JOYSTICKHATMOVE, eventData);
            }
        }
        break;

    case SDL_CONTROLLERBUTTONDOWN:
        {
            using namespace JoystickButtonDown;

            unsigned button = evt.cbutton.button;
            SDL_JoystickID joystickID = evt.cbutton.which;
            JoystickState& state = joysticks_[joystickID];

            VariantMap& eventData = GetEventDataMap();
            eventData[P_JOYSTICKID] = joystickID;
            eventData[P_BUTTON] = button;

            if (button < state.buttons_.Size())
            {
                state.buttons_[button] = true;
                state.buttonPress_[button] = true;
                SendEvent(E_JOYSTICKBUTTONDOWN, eventData);
            }
        }
        break;

    case SDL_CONTROLLERBUTTONUP:
        {
            using namespace JoystickButtonUp;

            unsigned button = evt.cbutton.button;
            SDL_JoystickID joystickID = evt.cbutton.which;
            JoystickState& state = joysticks_[joystickID];

            VariantMap& eventData = GetEventDataMap();
            eventData[P_JOYSTICKID] = joystickID;
            eventData[P_BUTTON] = button;

            if (button < state.buttons_.Size())
            {
                state.buttons_[button] = false;
                SendEvent(E_JOYSTICKBUTTONUP, eventData);
            }
        }
        break;

    case SDL_CONTROLLERAXISMOTION:
        {
            using namespace JoystickAxisMove;

            SDL_JoystickID joystickID = evt.caxis.which;
            JoystickState& state = joysticks_[joystickID];

            VariantMap& eventData = GetEventDataMap();
            eventData[P_JOYSTICKID] = joystickID;
            eventData[P_AXIS] = evt.caxis.axis;
            eventData[P_POSITION] = Clamp((float)evt.caxis.value / 32767.0f, -1.0f, 1.0f);

            if (evt.caxis.axis < state.axes_.Size())
            {
                state.axes_[evt.caxis.axis] = eventData[P_POSITION].GetFloat();
                SendEvent(E_JOYSTICKAXISMOVE, eventData);
            }
        }
        break;

    case SDL_WINDOWEVENT:
        {
            switch (evt.window.event)
            {
            case SDL_WINDOWEVENT_MINIMIZED:
                minimized_ = true;
                SendInputFocusEvent();
                break;

            case SDL_WINDOWEVENT_MAXIMIZED:
            case SDL_WINDOWEVENT_RESTORED:
                minimized_ = false;
                SendInputFocusEvent();
            #ifdef IOS
                // On iOS we never lose the GL context, but may have done GPU object changes that could not be applied yet.
                // Apply them now
                graphics_->Restore();
            #endif
                break;

            #ifdef ANDROID
            case SDL_WINDOWEVENT_FOCUS_GAINED:
                // Restore GPU objects to the new GL context
                graphics_->Restore();
                break;
            #endif

            case SDL_WINDOWEVENT_RESIZED:
                graphics_->WindowResized();
                break;
            case SDL_WINDOWEVENT_MOVED:
                graphics_->WindowMoved();
                break;
            }
        }
        break;

    case SDL_DROPFILE:
        {
            using namespace DropFile;

            VariantMap& eventData = GetEventDataMap();
            eventData[P_FILENAME] = GetInternalPath(String(evt.drop.file));
            SDL_free(evt.drop.file);

            SendEvent(E_DROPFILE, eventData);
        }
        break;

    case SDL_QUIT:
        SendEvent(E_EXITREQUESTED);
        break;
    }
}

void Input::HandleScreenMode(StringHash eventType, VariantMap& eventData)
{
    // Reset input state on subsequent initializations
    if (!initialized_)
        Initialize();
    else
        ResetState();

    // Re-enable cursor clipping, and re-center the cursor (if needed) to the new screen size, so that there is no erroneous
    // mouse move event. Also get new window ID if it changed
    SDL_Window* window = graphics_->GetImpl()->GetWindow();
    windowID_ = SDL_GetWindowID(window);

    if (!mouseVisible_)
    {
        IntVector2 center(graphics_->GetWidth() / 2, graphics_->GetHeight() / 2);
        SetMousePosition(center);
        lastMousePosition_ = center;
    }

    // Resize screen joysticks to new screen size
    for (HashMap<SDL_JoystickID, JoystickState>::Iterator i = joysticks_.Begin(); i != joysticks_.End(); ++i)
    {
        UIElement* screenjoystick = i->second_.screenJoystick_;
        if (screenjoystick)
            screenjoystick->SetSize(graphics_->GetWidth(), graphics_->GetHeight());
    }
    
    focusedThisFrame_ = true;

    // After setting a new screen mode we should not be minimized
    minimized_ = (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED) != 0;
}

void Input::HandleBeginFrame(StringHash eventType, VariantMap& eventData)
{
    // Update input right at the beginning of the frame
    Update();
}

void Input::HandleScreenJoystickTouch(StringHash eventType, VariantMap& eventData)
{
    using namespace TouchBegin;

    // Only interested in events from screen joystick(s)
    TouchState& state = touches_[eventData[P_TOUCHID].GetInt()];
    IntVector2 position(state.position_.x_, state.position_.y_);
    UIElement* element = eventType == E_TOUCHBEGIN ? GetSubsystem<UI>()->GetElementAt(position) : state.touchedElement_;
    if (!element)
        return;
    Variant variant = element->GetVar(VAR_SCREEN_JOYSTICK_ID);
    if (variant.IsEmpty())
        return;
    SDL_JoystickID joystickID = variant.GetInt();

    if (eventType == E_TOUCHEND)
        state.touchedElement_.Reset();
    else
        state.touchedElement_ = element;

    // Prepare a fake SDL event
    SDL_Event evt;

    const String& name = element->GetName();
    if (name.StartsWith("Button"))
    {
        if (eventType == E_TOUCHMOVE)
            return;

        // Determine whether to inject a joystick event or keyboard/mouse event
        Variant keyBindingVar = element->GetVar(VAR_BUTTON_KEY_BINDING);
        Variant mouseButtonBindingVar = element->GetVar(VAR_BUTTON_MOUSE_BUTTON_BINDING);
        if (keyBindingVar.IsEmpty() && mouseButtonBindingVar.IsEmpty())
        {
            evt.type = eventType == E_TOUCHBEGIN ? SDL_JOYBUTTONDOWN : SDL_JOYBUTTONUP;
            evt.jbutton.which = joystickID;
            evt.jbutton.button = ToUInt(name.Substring(6));
        }
        else
        {
            if (!keyBindingVar.IsEmpty())
            {
                evt.type = eventType == E_TOUCHBEGIN ? SDL_KEYDOWN : SDL_KEYUP;
                evt.key.keysym.sym = keyBindingVar.GetInt();
                evt.key.keysym.scancode = SDL_SCANCODE_UNKNOWN;
            }
            if (!mouseButtonBindingVar.IsEmpty())
            {
                // Mouse button are sent as extra events besides key events
                // Disable touch emulation handling during this to prevent endless loop
                bool oldTouchEmulation = touchEmulation_;
                touchEmulation_ = false;

                SDL_Event evt;
                evt.type = eventType == E_TOUCHBEGIN ? SDL_MOUSEBUTTONDOWN : SDL_MOUSEBUTTONUP;
                evt.button.button = mouseButtonBindingVar.GetInt();
                HandleSDLEvent(&evt);

                touchEmulation_ = oldTouchEmulation;
            }
        }
    }
    else if (name.StartsWith("Hat"))
    {
        Variant keyBindingVar = element->GetVar(VAR_BUTTON_KEY_BINDING);
        if (keyBindingVar.IsEmpty())
        {
            evt.type = SDL_JOYHATMOTION;
            evt.jaxis.which = joystickID;
            evt.jhat.hat = ToUInt(name.Substring(3));
            evt.jhat.value = HAT_CENTER;
            if (eventType != E_TOUCHEND)
            {
                IntVector2 relPosition = position - element->GetScreenPosition() - element->GetSize() / 2;
                if (relPosition.y_ < 0 && Abs(relPosition.x_ * 3 / 2) < Abs(relPosition.y_))
                    evt.jhat.value |= HAT_UP;
                if (relPosition.y_ > 0 && Abs(relPosition.x_ * 3 / 2) < Abs(relPosition.y_))
                    evt.jhat.value |= HAT_DOWN;
                if (relPosition.x_ < 0 && Abs(relPosition.y_ * 3 / 2) < Abs(relPosition.x_))
                    evt.jhat.value |= HAT_LEFT;
                if (relPosition.x_ > 0 && Abs(relPosition.y_ * 3 / 2) < Abs(relPosition.x_))
                    evt.jhat.value |= HAT_RIGHT;
            }
        }
        else
        {
            // Hat is binded by 4 keys, like 'WASD'
            String keyBinding = keyBindingVar.GetString();

            if (eventType == E_TOUCHEND)
            {
                evt.type = SDL_KEYUP;
                evt.key.keysym.sym = element->GetVar(VAR_LAST_KEYSYM).GetInt();
                if (!evt.key.keysym.sym)
                    return;

                element->SetVar(VAR_LAST_KEYSYM, 0);
            }
            else
            {
                evt.type = SDL_KEYDOWN;
                IntVector2 relPosition = position - element->GetScreenPosition() - element->GetSize() / 2;
                if (relPosition.y_ < 0 && Abs(relPosition.x_ * 3 / 2) < Abs(relPosition.y_))
                    evt.key.keysym.sym = keyBinding[0];
                else if (relPosition.y_ > 0 && Abs(relPosition.x_ * 3 / 2) < Abs(relPosition.y_))
                    evt.key.keysym.sym = keyBinding[1];
                else if (relPosition.x_ < 0 && Abs(relPosition.y_ * 3 / 2) < Abs(relPosition.x_))
                    evt.key.keysym.sym = keyBinding[2];
                else if (relPosition.x_ > 0 && Abs(relPosition.y_ * 3 / 2) < Abs(relPosition.x_))
                    evt.key.keysym.sym = keyBinding[3];
                else
                    return;

                if (eventType == E_TOUCHMOVE && evt.key.keysym.sym != element->GetVar(VAR_LAST_KEYSYM).GetInt())
                {
                    // Dragging past the directional boundary will cause an additional key up event for previous key symbol
                    SDL_Event evt;
                    evt.type = SDL_KEYUP;
                    evt.key.keysym.sym = element->GetVar(VAR_LAST_KEYSYM).GetInt();
                    if (evt.key.keysym.sym)
                    {
                        evt.key.keysym.scancode = SDL_SCANCODE_UNKNOWN;
                        HandleSDLEvent(&evt);
                    }

                    element->SetVar(VAR_LAST_KEYSYM, 0);
                }

                evt.key.keysym.scancode = SDL_SCANCODE_UNKNOWN;

                element->SetVar(VAR_LAST_KEYSYM, evt.key.keysym.sym);
            }
        }
    }
    else
        return;

    // Handle the fake SDL event to turn it into Atomic genuine event
    HandleSDLEvent(&evt);
}

}
