using System;
using System.Collections;
using System.Collections.Generic;
using TMPro;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.SceneManagement;

public class RoomEnterHandler : MonoBehaviour
{
    [Serializable]
    public class RoomTarget
    {
        public string roomId;
        public Transform spawnPoint;
        public GameObject roomRoot;
        public UnityEvent onEnter;
    }

    [Header("Enter Mode")]
    [Tooltip("켜면 RoomData의 Scene Name으로 씬을 이동합니다. 끄면 같은 씬 안에서 위치 이동/방 오브젝트 활성화를 합니다.")]
    [SerializeField] private bool useSceneLoading = false;

    [Header("Same Scene Movement")]
    [SerializeField] private Transform playerRoot;
    [SerializeField] private bool deactivateOtherRoomRoots = false;
    [SerializeField] private List<RoomTarget> roomTargets = new List<RoomTarget>();

    [Header("UI")]
    [SerializeField] private GameObject roomSelectRoot;
    [SerializeField] private bool hideRoomSelectOnEnter = true;

    [Header("Room Enter Message UI")]
    [Tooltip("방 입장 메시지 패널입니다.")]
    [SerializeField] private GameObject roomEnterMessagePanel;

    [Tooltip("방 입장 메시지를 표시할 TextMeshProUGUI입니다.")]
    [SerializeField] private TextMeshProUGUI roomEnterMessageText;

    [Tooltip("방 입장 메시지 전체 Root입니다. 보통 RoomEnterMessageCanvas를 넣습니다.")]
    [SerializeField] private Transform roomEnterMessageRoot;

    [Tooltip("메시지가 화면에 표시되는 시간입니다.")]
    [SerializeField] private float roomEnterMessageDuration = 2f;

    [Tooltip("{0} 자리에 RoomData의 RoomName이 들어갑니다.")]
    [SerializeField] private string roomEnterMessageFormat = "{0}에 입장했습니다";

    [Header("Room Enter Message Position")]
    [Tooltip("메시지를 기준으로 배치할 카메라입니다. XR Origin > Camera Offset > Main Camera를 넣으세요.")]
    [SerializeField] private Transform messageCameraTarget;

    [Tooltip("켜면 방 입장 메시지가 카메라 앞쪽으로 자동 이동합니다.")]
    [SerializeField] private bool placeMessageInFrontOfCamera = true;

    [Tooltip("카메라 앞 몇 m 위치에 메시지를 띄울지 정합니다.")]
    [SerializeField] private float messageDistance = 1.6f;

    [Tooltip("월드 기준 위/아래 위치 보정값입니다. 양수면 위로 올라갑니다.")]
    [SerializeField] private float messageHeightOffset = 0.25f;

    [Tooltip("글자가 뒤집혀 보이면 켜세요.")]
    [SerializeField] private bool flipMessageRotation = false;

    [Header("Events")]
    public UnityEvent onAnyRoomEntered;

    private Coroutine roomEnterMessageCoroutine;

    private void Awake()
    {
        if (messageCameraTarget == null && Camera.main != null)
        {
            messageCameraTarget = Camera.main.transform;
        }

        if (roomEnterMessagePanel != null)
        {
            roomEnterMessagePanel.SetActive(false);
        }
    }

    public void EnterRoom(RoomData roomData)
    {
        if (roomData == null)
        {
            Debug.LogWarning($"[{nameof(RoomEnterHandler)}] RoomData가 없습니다.");
            return;
        }

        if (hideRoomSelectOnEnter && roomSelectRoot != null)
        {
            roomSelectRoot.SetActive(false);
        }

        if (useSceneLoading)
        {
            EnterRoomByScene(roomData);
        }
        else
        {
            EnterRoomInSameScene(roomData);
        }

        onAnyRoomEntered?.Invoke();
    }

    private void EnterRoomByScene(RoomData roomData)
    {
        if (!roomData.HasSceneName())
        {
            Debug.LogWarning($"[{nameof(RoomEnterHandler)}] Scene Name이 비어 있습니다: {roomData.RoomName}");
            return;
        }

        SceneManager.LoadScene(roomData.SceneName);
    }

    private void EnterRoomInSameScene(RoomData roomData)
    {
        RoomTarget target = FindTarget(roomData.RoomId);

        if (target == null)
        {
            Debug.Log($"[{nameof(RoomEnterHandler)}] 방 입장 테스트: {roomData.RoomName} / roomId: {roomData.RoomId}");
            return;
        }

        if (deactivateOtherRoomRoots)
        {
            foreach (RoomTarget roomTarget in roomTargets)
            {
                if (roomTarget != null && roomTarget.roomRoot != null)
                {
                    roomTarget.roomRoot.SetActive(roomTarget == target);
                }
            }
        }
        else if (target.roomRoot != null)
        {
            target.roomRoot.SetActive(true);
        }

        if (playerRoot != null && target.spawnPoint != null)
        {
            CharacterController controller = playerRoot.GetComponent<CharacterController>();
            bool hadController = controller != null;

            if (hadController)
            {
                controller.enabled = false;
            }

            playerRoot.SetPositionAndRotation(target.spawnPoint.position, target.spawnPoint.rotation);

            if (hadController)
            {
                controller.enabled = true;
            }
        }

        target.onEnter?.Invoke();

        ShowRoomEnterMessage(roomData);

        Debug.Log($"[{nameof(RoomEnterHandler)}] 방 입장: {roomData.RoomName}");
    }

    private RoomTarget FindTarget(string roomId)
    {
        return roomTargets.Find(target => target != null && target.roomId == roomId);
    }

    private void ShowRoomEnterMessage(RoomData roomData)
    {
        if (roomData == null)
            return;

        if (roomEnterMessagePanel == null || roomEnterMessageText == null)
            return;

        if (roomEnterMessageRoot != null)
        {
            roomEnterMessageRoot.gameObject.SetActive(true);
        }

        PlaceRoomEnterMessageInFrontOfCamera();

        string roomName = roomData.RoomName;
        roomEnterMessageText.text = string.Format(roomEnterMessageFormat, roomName);

        roomEnterMessagePanel.SetActive(true);

        if (roomEnterMessageCoroutine != null)
        {
            StopCoroutine(roomEnterMessageCoroutine);
        }

        roomEnterMessageCoroutine = StartCoroutine(HideRoomEnterMessageAfterDelay());
    }

    private void PlaceRoomEnterMessageInFrontOfCamera()
    {
        if (!placeMessageInFrontOfCamera)
            return;

        if (roomEnterMessageRoot == null)
            return;

        if (messageCameraTarget == null)
        {
            if (Camera.main != null)
            {
                messageCameraTarget = Camera.main.transform;
            }
            else
            {
                return;
            }
        }

        // 카메라가 아래를 보고 있어도 메시지가 바닥으로 들어가지 않게
        // 카메라 forward에서 Y값을 제거해서 수평 방향만 사용
        Vector3 flatForward = messageCameraTarget.forward;
        flatForward.y = 0f;

        if (flatForward.sqrMagnitude < 0.001f)
        {
            flatForward = messageCameraTarget.parent != null
                ? messageCameraTarget.parent.forward
                : Vector3.forward;

            flatForward.y = 0f;
        }

        flatForward.Normalize();

        Vector3 targetPosition =
            messageCameraTarget.position +
            flatForward * messageDistance +
            Vector3.up * messageHeightOffset;

        roomEnterMessageRoot.position = targetPosition;

        Quaternion targetRotation = Quaternion.LookRotation(flatForward, Vector3.up);

        if (flipMessageRotation)
        {
            targetRotation *= Quaternion.Euler(0f, 180f, 0f);
        }

        roomEnterMessageRoot.rotation = targetRotation;
    }

    private IEnumerator HideRoomEnterMessageAfterDelay()
    {
        yield return new WaitForSeconds(roomEnterMessageDuration);

        if (roomEnterMessagePanel != null)
        {
            roomEnterMessagePanel.SetActive(false);
        }

        roomEnterMessageCoroutine = null;
    }
}