using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using System.Linq;

public class KeyBoardSelector : MonoBehaviour
{
    Button _lastSelectBtn;
    List<Button> _selectables = new();
    EventSystem _eventSystem;
    PointerEventData _pointerEventData;
    public bool doing = false;
    private float _lastAutoSetFirstBtnTime;
    public static KeyBoardSelector ins;

    void Start()
    {
        ins = this;
        _eventSystem = FindObjectOfType<EventSystem>();
        _pointerEventData = new PointerEventData(_eventSystem);
        gameObject.AddComponent<KeyBoardInterface>();
    }
    
    void Update()
    {
        if (doing)
        {
            RefreshLastSelectBtn();
            if (SB_EventSystem.ins.simulateMouseIsAwaked)
            {
                if (!IsBtnCanReach(_lastSelectBtn)) Quit();
            }
            else
            {
                if (!IsLastBtnValid()) Quit();
            }
        }
        else
        {
            if (Time.realtimeSinceStartup - _lastAutoSetFirstBtnTime > 0.2)
            {
                _lastAutoSetFirstBtnTime = Time.realtimeSinceStartup;
                RefreshLastSelectBtn();
                if (SB_EventSystem.ins.simulateMouseIsAwaked)
                {
                    if (!IsBtnCanReach(_lastSelectBtn)) SetFirstSelectBtn();
                }
                else
                {
                    if (!IsLastBtnValid()) SetFirstSelectBtn();
                }
            }
        }
    }

    public void Quit()
    {
        doing = false;
        SB_EventSystem.ins.mouseConfirm.Hide();
    }

    public void Enter()
    {
        RefreshLastSelectBtn();
        SB_EventSystem.ins.mouseConfirm.OnClikc_Confirm(false);
    }

    public void HandleInput(int delta)
    {
        doing = true;
        RefreshLastSelectBtn();
        UpdateSelectables();
        if (IsLastBtnValid())
        {
            Button nextOne = KeyBoardNavigation.Next(_lastSelectBtn, delta);
            if (nextOne == null) return;
            _lastSelectBtn = nextOne;
            SB_EventSystem.ins.mouseConfirm.SetSelectable(_lastSelectBtn);
        }
        else
        {
            if (_selectables.Count > 0)
            {
                Button nextOne = KeyBoardNavigation.Next(_selectables[0], delta, true);
                if (nextOne == null) return;
                _lastSelectBtn = nextOne;
                SB_EventSystem.ins.mouseConfirm.SetSelectable(_lastSelectBtn);
            }
        }
    }

    void SetFirstSelectBtn()
    {
        doing = true;
        RefreshLastSelectBtn();
        UpdateSelectables();
        if (_selectables.Count > 0)
        {
            Button nextOne = KeyBoardNavigation.Next(_selectables[0], 1, true);
            if (nextOne == null) return;
            _lastSelectBtn = nextOne;
            SB_EventSystem.ins.mouseConfirm.SetSelectable(_lastSelectBtn);
        }
    }

    void UpdateSelectables()
    {
        _selectables.Clear();
        Button[] buttons = FindObjectsOfType<Button>();
        List<RaycastResult> raycastResults = new List<RaycastResult>();
        foreach (var btn in buttons)
        {
            if (!btn.interactable) continue;
            _pointerEventData.position = JCUnityLib.RectTransformUtils.GetPositionByPivot(btn.transform as RectTransform, Vector2.one * 0.5f);
            _eventSystem.RaycastAll(_pointerEventData, raycastResults);
            Selectable selectable;
            if (raycastResults.Count > 0 && raycastResults[0].gameObject && (selectable = raycastResults[0].gameObject.GetComponentInParent<Selectable>()) && selectable == btn && KeyBoardNavigation.IsNavigationButton(selectable.GetComponent<Button>()))
            {
                _selectables.Add(btn);
            }
        }
    }

    bool IsLastBtnValid()
    {
        if (!_lastSelectBtn) return false;
        if (!_lastSelectBtn.interactable) return false;
        List<RaycastResult> raycastResults = new List<RaycastResult>();
        _pointerEventData.position = JCUnityLib.RectTransformUtils.GetPositionByPivot(_lastSelectBtn.transform as RectTransform, Vector2.one * 0.5f);
        _eventSystem.RaycastAll(_pointerEventData, raycastResults);
        Selectable selectable;
        if (raycastResults.Count > 0 && raycastResults[0].gameObject && (selectable = raycastResults[0].gameObject.GetComponentInParent<Selectable>()) && selectable == _lastSelectBtn && KeyBoardNavigation.IsNavigationButton(selectable.GetComponent<Button>()))
        {
            return true;
        }
        return false;
    }

    bool IsBtnCanReach(Button btn)
    {
        if (!btn || !btn.interactable || !btn.gameObject || !btn.gameObject.activeInHierarchy) return false;
        List<RaycastResult> raycastResults = new List<RaycastResult>();
        _pointerEventData.position = JCUnityLib.RectTransformUtils.GetPositionByPivot(btn.transform as RectTransform, Vector2.one * 0.5f);
        _eventSystem.RaycastAll(_pointerEventData, raycastResults);
        if (raycastResults.Count == 0) return false;
        RaycastResult rs = raycastResults[0];
        if (!rs.gameObject) return false;
        Button rayHitBtn = rs.gameObject.GetComponentInParent<Button>();
        return btn == rayHitBtn;
    }

    void RefreshLastSelectBtn()
    {
        if (SB_EventSystem.ins.mouseConfirm._targetSelectable) _lastSelectBtn = SB_EventSystem.ins.mouseConfirm._targetSelectable.GetComponent<Button>();
        else _lastSelectBtn = null;
    }
}

//public class KeyBoardSelector : MonoBehaviour
//{
//    Button _lastSelectBtn;
//    List<Button> _selectables = new();
//    EventSystem _eventSystem;
//    PointerEventData _pointerEventData;
//    public bool doing = false;
//    public static KeyBoardSelector ins;

//    void Start()
//    {
//        ins = this;
//        _eventSystem = FindObjectOfType<EventSystem>();
//        _pointerEventData = new PointerEventData(_eventSystem);
//        gameObject.AddComponent<KeyBoardInterface>();
//    }

//    void Update()
//    {
//        if (doing)
//        {
//            RefreshLastSelectBtn();
//            if (!IsLastBtnValid()) Quit();
//        }
//    }

//    public void Quit()
//    {
//        doing = false;
//        SB_EventSystem.ins.mouseConfirm.Hide();
//    }

//    public void Enter()
//    {
//        RefreshLastSelectBtn();
//        SB_EventSystem.ins.mouseConfirm.OnClikc_Confirm(false);
//    }

//    public void HandleInput(Vector2 pointer)
//    {
//        doing = true;
//        RefreshLastSelectBtn();
//        UpdateSelectables();
//        if (IsLastBtnValid())
//        {
//            Vector2 curPos = JCUnityLib.RectTransformUtils.GetPositionByPivot(_lastSelectBtn.transform as RectTransform, Vector2.one * 0.5f);
//            var selectableList = _selectables.FindAll(b => b != _lastSelectBtn && Vector2.Angle(pointer, (Vector2)JCUnityLib.RectTransformUtils.GetPositionByPivot(b.transform as RectTransform, Vector2.one * 0.5f) - curPos) <= 45);
//            if (selectableList.Count == 0)
//            {
//                //重新筛选
//                _selectables = _selectables.FindAll(b => b != _lastSelectBtn && Vector2.Angle(pointer, (Vector2)JCUnityLib.RectTransformUtils.GetPositionByPivot(b.transform as RectTransform, Vector2.one * 0.5f) - curPos) <= 80);
//                _selectables = _selectables.OrderBy(b => Vector2.Angle(pointer, (Vector2)JCUnityLib.RectTransformUtils.GetPositionByPivot(b.transform as RectTransform, Vector2.one * 0.5f) - curPos))
//                    .ThenBy(b => Vector2.Distance(JCUnityLib.RectTransformUtils.GetPositionByPivot(b.transform as RectTransform, Vector2.one * 0.5f), curPos))
//                    .ToList();
//            }
//            else
//            {
//                _selectables = selectableList.OrderBy(b => Vector2.Distance(JCUnityLib.RectTransformUtils.GetPositionByPivot(b.transform as RectTransform, Vector2.one * 0.5f), curPos)).ToList();
//            }
//            if (_selectables.Count > 0)
//            {
//                _lastSelectBtn = _selectables[0];
//                SB_EventSystem.ins.mouseConfirm.SetSelectable(_lastSelectBtn);
//            }
//        }
//        else
//        {
//            if (_selectables.Count > 0)
//            {
//                Vector2 centerPoint = new Vector2(Screen.width, Screen.height) / 2f;
//                _selectables.Sort((a, b) =>
//                {
//                    return Vector2.Distance(a.transform.position, centerPoint) - Vector2.Distance(b.transform.position, centerPoint) < 0 ? -1 : 1;
//                });
//                _lastSelectBtn = _selectables[0];
//                SB_EventSystem.ins.mouseConfirm.SetSelectable(_lastSelectBtn);
//            }
//        }
//    }

//    void UpdateSelectables()
//    {
//        _selectables.Clear();
//        Button[] buttons = FindObjectsOfType<Button>();
//        List<RaycastResult> raycastResults = new List<RaycastResult>();
//        foreach (var btn in buttons)
//        {
//            if (!btn.interactable) continue;
//            _pointerEventData.position = JCUnityLib.RectTransformUtils.GetPositionByPivot(btn.transform as RectTransform, Vector2.one * 0.5f);
//            _eventSystem.RaycastAll(_pointerEventData, raycastResults);
//            Selectable selectable;
//            if (raycastResults.Count > 0 && raycastResults[0].gameObject && (selectable = raycastResults[0].gameObject.GetComponentInParent<Selectable>()) && selectable == btn)
//            {
//                _selectables.Add(btn);
//            }
//        }
//    }

//    bool IsLastBtnValid()
//    {
//        if (!_lastSelectBtn) return false;
//        if (!_lastSelectBtn.interactable) return false;
//        List<RaycastResult> raycastResults = new List<RaycastResult>();
//        _pointerEventData.position = JCUnityLib.RectTransformUtils.GetPositionByPivot(_lastSelectBtn.transform as RectTransform, Vector2.one * 0.5f);
//        _eventSystem.RaycastAll(_pointerEventData, raycastResults);
//        Selectable selectable;
//        if (raycastResults.Count > 0 && raycastResults[0].gameObject && (selectable = raycastResults[0].gameObject.GetComponentInParent<Selectable>()) && selectable == _lastSelectBtn)
//        {
//            return true;
//        }
//        return false;
//    }

//    void RefreshLastSelectBtn()
//    {
//        if (SB_EventSystem.ins.mouseConfirm._targetSelectable) _lastSelectBtn = SB_EventSystem.ins.mouseConfirm._targetSelectable.GetComponent<Button>();
//        else _lastSelectBtn = null;
//    }
//}