// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

#pragma once
#include <IReactInstance.h>
#include <JSValue.h>
#include <ReactPointerEventArgs.h>
#include <UI.Xaml.Documents.h>
#include <winrt/Windows.Devices.Input.h>
#include <optional>
#include <set>
#include "Utils/BatchingEventEmitter.h"
#include "XamlView.h"

namespace winrt {
using namespace Windows::UI;
using namespace xaml;
using namespace xaml::Controls;
using namespace xaml::Input;
using namespace Windows::Foundation;
using namespace xaml::Media;
} // namespace winrt

namespace Microsoft::ReactNative {

class TouchEventHandler {
 public:
  TouchEventHandler(const Mso::React::IReactContext &context);
  virtual ~TouchEventHandler();

  void AddTouchHandlers(XamlView xamlView, XamlView rootView = nullptr, bool handledEventsToo = false);
  void RemoveTouchHandlers();
  winrt::Microsoft::ReactNative::BatchingEventEmitter &BatchingEmitter() noexcept;

 private:
  void OnPointerPressed(const winrt::IInspectable &, const winrt::PointerRoutedEventArgs &args);
  void OnPointerReleased(const winrt::IInspectable &, const winrt::PointerRoutedEventArgs &args);
  void OnPointerCanceled(const winrt::IInspectable &, const winrt::PointerRoutedEventArgs &args);
  void OnPointerCaptureLost(const winrt::IInspectable &, const winrt::PointerRoutedEventArgs &args);
  void OnPointerExited(const winrt::IInspectable &, const winrt::PointerRoutedEventArgs &args);
  void OnPointerMoved(const winrt::IInspectable &, const winrt::PointerRoutedEventArgs &args);
  winrt::IInspectable m_pressedHandler;
  winrt::IInspectable m_releasedHandler;
  winrt::IInspectable m_canceledHandler;
  winrt::IInspectable m_captureLostHandler;
  winrt::IInspectable m_exitedHandler;
  winrt::IInspectable m_movedHandler;

#ifdef USE_WINUI3
  using PointerDeviceType = winrt::Microsoft::UI::Input::PointerDeviceType;
#else
  using PointerDeviceType = winrt::Windows::Devices::Input::PointerDeviceType;
#endif

  struct ReactPointer {
    int64_t target = 0;
    int64_t identifier = 0;
    uint32_t pointerId = 0;
    uint64_t timestamp = 0;
    winrt::Point positionRoot = {0, 0};
    winrt::Point positionView = {0, 0};
    PointerDeviceType deviceType{PointerDeviceType::Mouse};
    float pressure = 0;
    bool isLeftButton = false;
    bool isRightButton = false;
    bool isMiddleButton = false;
    bool isBarrelButton = false;
    bool isHorizontalScrollWheel = false;
    bool isEraser = false;
    bool shiftKey = false;
    bool ctrlKey = false;
    bool altKey = false;
  };
  size_t AddReactPointer(const winrt::PointerRoutedEventArgs &args, int64_t tag, xaml::UIElement sourceElement);
  ReactPointer
  CreateReactPointer(const winrt::PointerRoutedEventArgs &args, int64_t tag, xaml::UIElement sourceElement);
  void
  UpdateReactPointer(ReactPointer &pointer, const winrt::PointerRoutedEventArgs &args, xaml::UIElement sourceElement);
  void UpdatePointersInViews(
      const winrt::PointerRoutedEventArgs &args,
      xaml::UIElement sourceElement,
      std::vector<int64_t> &&newViews);

  enum class TouchEventType { Start = 0, End, Move, Cancel, CaptureLost, PointerEntered, PointerExited, PointerMove };
  void OnPointerConcluded(TouchEventType eventType, const winrt::PointerRoutedEventArgs &args);
  void DispatchTouchEvent(TouchEventType eventType, size_t pointerIndex);
  bool DispatchBackEvent();
  const char *GetPointerDeviceTypeName(PointerDeviceType deviceType) noexcept;

  winrt::Microsoft::ReactNative::PointerEventKind GetPointerEventKind(TouchEventType eventType) noexcept;
  const wchar_t *GetTouchEventTypeName(TouchEventType eventType) noexcept;

  std::optional<size_t> IndexOfPointerWithId(uint32_t pointerId);
  winrt::Microsoft::ReactNative::JSValue GetPointerJson(const ReactPointer &pointer, int64_t target);

  struct TagSet {
    std::unordered_set<int64_t> tags;
    std::vector<int64_t> orderedTags;
  };

  std::vector<ReactPointer> m_pointers;
  std::unordered_map<uint32_t /*pointerId*/, TagSet /*tags*/> m_pointersInViews;
  int64_t m_touchId = 0;

  bool PropagatePointerEventAndFindReactSourceBranch(
      const winrt::Microsoft::ReactNative::ReactPointerEventArgs &args,
      std::vector<int64_t> *pTagsForBranch,
      xaml::UIElement *pSourceElement);

  XamlView m_xamlView;
  XamlView m_rootView;
  Mso::CntPtr<const Mso::React::IReactContext> m_context;
  std::shared_ptr<winrt::Microsoft::ReactNative::BatchingEventEmitter> m_batchingEventEmitter;
};

} // namespace Microsoft::ReactNative