using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class ClientDropItemUtility : Singleton<ClientDropItemUtility>
{
    public static UnityEngine.Events.UnityAction<int> OnItemPickup;
    private const float OFFSET = 1;
    private int m_TotalDropCount;
    private int m_DropedCount;
    private Vector3 m_DropPos;
    private Vector3 m_Dir;
    private List<int> m_IndexList = new List<int>();

    private List<DropItem> m_DropItemList = new List<DropItem>();

    public bool TryGetDropItem(out DropItem item)
    {
        var _hero = PlayerDatas.Instance.hero;

        if (_hero == null || m_DropItemList.Count == 0)
        {
            item = null;
            return false;
        }

        m_DropItemList.Sort((i1, i2) =>
        {
            var _d1 = MathUtility.DistanceSqrtXZ(_hero.Pos, i1.transform.position);
            var _d2 = MathUtility.DistanceSqrtXZ(_hero.Pos, i2.transform.position);
            if (_d2 > _d1)
            {
                return -1;
            }
            else if (_d2 < _d1)
            {
                return 1;
            }
            return 0;
        });

        item = m_DropItemList[0];
        return true;
    }

    public void Update()
    {
        var _hero = PlayerDatas.Instance.hero;
        if (_hero == null)
        {
            return;
        }

        float _dis;
        DropItem _item;
        for (int i = m_DropItemList.Count - 1; i >= 0; --i)
        {
            _item = m_DropItemList[i];
            _dis = MathUtility.DistanceSqrtXZ(_item.transform.position, _hero.Pos);
            if (_dis < .25f)
            {
                if (OnItemPickup != null)
                {
                    OnItemPickup(_item.itemId);
                }

                Release(_item);
            }
        }
    }

    public void ReleaseAll()
    {
        for (int i = m_DropItemList.Count - 1; i >= 0; --i)
        {
            Release(m_DropItemList[i]);
        }
    }

    public void Release(DropItem item)
    {
        DropItem.Reycle(item);
        m_DropItemList.Remove(item);
    }

    public void Drop(Vector3 center, int[] itemIds)
    {
        if (itemIds == null || itemIds.Length == 0)
        {
            return;
        }

        RaycastHit _hit;
        if (!Physics.Raycast(center + new Vector3(0, 50, 0),
                             Vector3.down,
                             out _hit,
                             80,
                             LayerUtility.WalkbleMask))
        {
            return;
        }

        m_IndexList.Clear();
        m_DropPos = center;
        m_DropedCount = 0;
        m_TotalDropCount = itemIds.Length;
        m_Dir = Vector3.forward;

        DropItem _item = DropItem.Drop(itemIds[m_DropedCount],
                         _hit.point,
                         CameraController.Instance.CameraObject);
        m_DropItemList.Add(_item);
        m_DropedCount += 1;

        int _x = Mathf.CeilToInt(m_DropPos.x * 100000);
        int _z = Mathf.CeilToInt(m_DropPos.z * 10);
        m_IndexList.Add(_x + _z);

        DropNext(itemIds);
    }

    public void DropNext(int[] itemIds)
    {
        if (m_DropedCount < m_TotalDropCount)
        {
            var _nextDir = MathUtility.Rotate90_XZ_CW(m_Dir);
            var _nextPos = m_DropPos + _nextDir * OFFSET;
            int _x = Mathf.CeilToInt(_nextPos.x * 100000);
            int _z = Mathf.CeilToInt(_nextPos.z * 10);
            int _index = _x + _z;

            if (m_IndexList.Contains(_index))
            {
                m_DropPos = m_DropPos + m_Dir * OFFSET;

                _x = Mathf.CeilToInt(m_DropPos.x * 100000);
                _z = Mathf.CeilToInt(m_DropPos.z * 10);
                _index = _x + _z;
            }
            else
            {
                m_Dir = _nextDir;
                m_DropPos = _nextPos;
            }

            m_IndexList.Add(_index);

            RaycastHit _hit;
            if (Physics.Raycast(m_DropPos + new Vector3(0, 50, 0),
                                 Vector3.down,
                                 out _hit,
                                 80,
                                 LayerUtility.WalkbleMask))
            {
                DropItem _item = DropItem.Drop(itemIds[m_DropedCount],
                                 _hit.point,
                                 CameraController.Instance.CameraObject);
                m_DropItemList.Add(_item);
                m_DropedCount += 1;
            }

            DropNext(itemIds);
        }
    }
}