using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR.Interaction.Toolkit;
using UnityEngine.XR.Interaction.Toolkit.Interactables;

public enum BlockColor { Red, Blue, Green }
public enum BlockShapeType { TShape, CShape }

public class PuzzleBlock : MonoBehaviour
{
    [field: SerializeField] public BlockColor Color { get; private set; }
    [field: SerializeField] public BlockShapeType ShapeType { get; private set; }

    [SerializeField] private Transform snapPoint;

    public static event Action<BlockColor> OnPuzzleCompleted;

    private static readonly HashSet<PuzzleBlock> allBlocks = new HashSet<PuzzleBlock>();

    private PuzzleBlock nearbyPartner;
    private bool isConnected;

    // ★ワールド情報ではなく「親階層」と「ローカル情報」を記憶
    private Transform initialParent;
    private Vector3 initialLocalPosition;
    private Quaternion initialLocalRotation;
    private Vector3 initialLocalScale;

    private Rigidbody rb;
    private XRGrabInteractable grabInteractable;

    private void Awake()
    {
        rb = GetComponent<Rigidbody>();
        grabInteractable = GetComponent<XRGrabInteractable>();

        // ★開始時の「親」と「ローカル座標・回転・スケール」を保持
        initialParent = transform.parent;
        initialLocalPosition = transform.localPosition;
        initialLocalRotation = transform.localRotation;
        initialLocalScale = transform.localScale;
    }

    private void OnEnable()
    {
        allBlocks.Add(this);
    }

    private void OnDisable()
    {
        allBlocks.Remove(this);
    }

    private void OnTriggerEnter(Collider other)
    {
        if (isConnected) return;

        PuzzleBlock partner = other.GetComponentInParent<PuzzleBlock>();
        if (partner != null && IsValidPartner(partner))
        {
            nearbyPartner = partner;
        }
    }

    private void OnTriggerExit(Collider other)
    {
        PuzzleBlock partner = other.GetComponentInParent<PuzzleBlock>();
        if (partner == nearbyPartner)
        {
            nearbyPartner = null;
        }
    }

    private bool IsValidPartner(PuzzleBlock partner)
    {
        if (partner == null || partner.isConnected) return false;
        return partner.Color == Color && partner.ShapeType != ShapeType;
    }

    public void OnReleased()
    {
        if (isConnected) return;

        if (nearbyPartner != null)
        {
            ConnectToPartner(nearbyPartner);
        }
    }

    private void ConnectToPartner(PuzzleBlock partner)
    {
        isConnected = true;
        partner.isConnected = true;

        if (snapPoint != null && partner.snapPoint != null)
        {
            transform.position = partner.snapPoint.position;
            transform.rotation = partner.snapPoint.rotation;
        }
        else
        {
            transform.position = partner.transform.position;
            transform.rotation = partner.transform.rotation;
        }

        LockBlockState();
        partner.LockBlockState();

        OnPuzzleCompleted?.Invoke(Color);

        BuffType buff = ConvertColorToBuffType(Color);
        if (PlayerStatusManager.Instance != null)
        {
            PlayerStatusManager.Instance.ApplyBuffsAndResume(buff, buff);
        }
    }

    private void LockBlockState()
    {
        if (rb != null)
        {
            rb.linearVelocity = Vector3.zero;
            rb.angularVelocity = Vector3.zero;
            rb.isKinematic = true;
        }
        if (grabInteractable != null) grabInteractable.enabled = false;
    }

    public void ResetBlock()
    {
        // 1. 手で掴んでいる場合は手離し処理
        ForceDrop();

        isConnected = false;
        nearbyPartner = null;

        // 2. ★親オブジェクト（Canvas）の子へ戻す
        if (initialParent != null && transform.parent != initialParent)
        {
            transform.SetParent(initialParent, false);
        }

        // 3. ★Canvas内のローカル位置・回転・スケールを完全復元
        transform.localPosition = initialLocalPosition;
        transform.localRotation = initialLocalRotation;
        transform.localScale = initialLocalScale;

        // 4. 物理状態の再初期化
        if (rb != null)
        {
            rb.isKinematic = false;
            rb.linearVelocity = Vector3.zero;
            rb.angularVelocity = Vector3.zero;
        }

        // 5. 掴み機能の再有効化
        if (grabInteractable != null)
        {
            grabInteractable.enabled = true;
        }
    }

    private void ForceDrop()
    {
        if (grabInteractable == null || !grabInteractable.isSelected) return;

        if (grabInteractable.interactionManager != null && grabInteractable.firstInteractorSelecting != null)
        {
            grabInteractable.interactionManager.SelectExit(grabInteractable.firstInteractorSelecting, grabInteractable);
        }
    }

    public static void ResetAllBlocksInScene()
    {
        foreach (var block in allBlocks)
        {
            if (block != null)
            {
                block.ResetBlock();
            }
        }
    }

    private BuffType ConvertColorToBuffType(BlockColor color)
    {
        return color switch
        {
            BlockColor.Red => BuffType.AttackUp,
            BlockColor.Blue => BuffType.DefenseUp,
            BlockColor.Green => BuffType.Heal,
            _ => BuffType.AttackUp
        };
    }
}