using System;
using System.Collections.Generic;
using BrewMonster.Scripts.Managers;
using CSNetwork.Protocols.RPCData;
using Cysharp.Threading.Tasks;
using UnityEngine;

namespace BrewMonster.Scripts
{
    public class PlayerModelPreview : MonoSingleton<PlayerModelPreview>
    {
        [SerializeField] private Transform modelRoot;
        [SerializeField] private bool enablePreviewCameraWithInventory = true;

        public List<GameObject> playerModels = new();
        public List<int> playerModelIds = new();

        /// <summary>
        /// Fired (with the roleId) the first time a model becomes active after loading completes.
        /// Subscribe from HostPlayerPortraitCapture so it can attach the portrait camera at the
        /// right moment even when the async load finishes after AttachToPlayerModelPreview is called.
        /// </summary>
        public event Action<int> OnModelReady;

        private int _loadVersion;

        private bool _hasRequestedPlayerModelId;
        private int _requestedPlayerModelId;

        private bool _inventoryPreviewActive;
        private bool _suppressHierarchyWatch;
        private bool _refreshQueued;
        private RoleInfo _lastPreviewRoleInfo;
        private Transform _lastOriginModelRoot;
        private int _lastOriginModelChildCount;

        private Camera _previewCamera;

        private void Awake()
        {
            if (modelRoot == null)
                modelRoot = transform;

            _previewCamera = GetComponent<Camera>();
        }

        private void OnDestroy()
        {
            ClearModelsImmediate();
        }

        private void LateUpdate()
        {
            if (!_inventoryPreviewActive || _suppressHierarchyWatch)
                return;

            Transform activeRoot = GetActivePreviewModelTransform();
            if (activeRoot == null)
            {
                if (_refreshQueued)
                {
                    _refreshQueued = false;
                    TryRefreshFromCachedRole();
                }

                return;
            }

            int currentChildCount = CountAllChildren(activeRoot);
            if (_lastOriginModelRoot != activeRoot || _lastOriginModelChildCount != currentChildCount)
            {
                bool hierarchyChanged = _lastOriginModelRoot != null;
                _lastOriginModelRoot = activeRoot;
                _lastOriginModelChildCount = currentChildCount;

                if (hierarchyChanged && _lastPreviewRoleInfo != null)
                    _refreshQueued = true;
            }

            if (_refreshQueued)
            {
                _refreshQueued = false;
                TryRefreshFromCachedRole();
            }
        }

        /// <summary>Called when Inventory UI opens — shows the host preview model on shared Bootstrap camera.</summary>
        public void BeginInventoryPreview(int roleId)
        {
            _inventoryPreviewActive = true;
            ResetHierarchyWatch();

            if (enablePreviewCameraWithInventory && _previewCamera != null)
                _previewCamera.enabled = true;

            ShowPlayerModel(roleId);
        }

        /// <summary>Called when Inventory UI closes — hides preview models. Camera stays enabled for login/character-select reuse.</summary>
        public void EndInventoryPreview()
        {
            _inventoryPreviewActive = false;
            _refreshQueued = false;
            _suppressHierarchyWatch = false;
            ResetHierarchyWatch();

            HideAllPlayerModels();
        }

        /// <summary>
        /// Loads one preview instance per role (via <see cref="NPCManager.GetModelPlayer"/>).
        /// All instances stay hidden until <see cref="ShowPlayerModel"/> is called.
        /// </summary>
        public async UniTask<bool> ShowAllPlayerModels(List<RoleInfo> roleInfos)
        {
            BMLogger.Log($"ShowAllPlayerModels: {roleInfos.Count}");
            _loadVersion++;
            int version = _loadVersion;

            if (roleInfos == null || roleInfos.Count == 0 || NPCManager.Instance == null)
            {
                ClearModels();
                _suppressHierarchyWatch = false;
                return false;
            }

            List<GameObject> oldModels = new List<GameObject>(playerModels);
            playerModels.Clear();
            playerModelIds.Clear();

            for (int i = 0; i < roleInfos.Count; i++)
            {
                RoleInfo role = roleInfos[i];
                GameObject model = await LoadPlayerModel(role);

                if (model == null)
                    continue;

                if (version != _loadVersion)
                {
                    Destroy(model);
                    return false;
                }

                model.transform.SetParent(modelRoot, false);
                model.transform.localPosition = Vector3.zero;
                model.transform.localRotation = Quaternion.identity;
                model.SetActive(false);

                playerModels.Add(model);
                playerModelIds.Add(role.roleid);

                ApplyRequestedModelVisibility();
            }

            for (int i = 0; i < oldModels.Count; i++)
            {
                if (oldModels[i] != null)
                {
                    Destroy(oldModels[i]);
                }
            }

            _suppressHierarchyWatch = false;
            if (_inventoryPreviewActive)
                SyncHierarchyBaseline();
            return true;
        }

        /// <summary>
        /// Shows the preview for the given role id (matches <see cref="RoleInfo.roleid"/>). Hides all others.
        /// </summary>
        public void ShowPlayerModel(int playerModelId)
        {
            _hasRequestedPlayerModelId = true;
            _requestedPlayerModelId = playerModelId;

            ApplyRequestedModelVisibility();
        }

        /// <summary>
        /// Applies the visibility of player models based on the requested player model id.
        /// Fires <see cref="OnModelReady"/> the first time a model transitions to active so that
        /// portrait capture systems can attach at the correct moment after async loading.
        /// </summary>
        private void ApplyRequestedModelVisibility()
        {
            if (!_hasRequestedPlayerModelId)
                return;

            int n = Mathf.Min(playerModels.Count, playerModelIds.Count);
            for (int i = 0; i < n; i++)
            {
                GameObject go = playerModels[i];
                if (go == null)
                    continue;

                bool shouldBeActive = playerModelIds[i] == _requestedPlayerModelId;
                bool wasActive = go.activeSelf;
                go.SetActive(shouldBeActive);

                if (shouldBeActive && !wasActive)
                    OnModelReady?.Invoke(playerModelIds[i]);
            }

            if (_inventoryPreviewActive)
                SyncHierarchyBaseline();
        }

        public void HideAllPlayerModels()
        {
            _hasRequestedPlayerModelId = false;
            for (int i = 0; i < playerModels.Count; i++)
            {
                if (playerModels[i] != null)
                {
                    playerModels[i].SetActive(false);
                }
            }
        }

        public void ClearModels()
        {
            for (int i = 0; i < playerModels.Count; i++)
            {
                if (playerModels[i] != null)
                {
                    Destroy(playerModels[i]);
                }
            }

            playerModels.Clear();
            playerModelIds.Clear();
        }

        private void ClearModelsImmediate()
        {
            for (int i = 0; i < playerModels.Count; i++)
            {
                if (modelRoot != null)
                {
                    if (playerModels[i] != null)
                    {
                        if (Application.isPlaying)
                            Destroy(playerModels[i]);
                        else
                            DestroyImmediate(playerModels[i]);
                    }
                }
            }

            playerModels.Clear();
            playerModelIds.Clear();
        }

        private async UniTask<GameObject> LoadPlayerModel(RoleInfo role)
        {
            var elemendataman = ElementDataManProvider.GetElementDataMan();
            GameObject model = await NPCManager.Instance.GetModelPlayer(role.occupation, role.gender);
            if (model == null)
                return null;

            model.SetActive(false);
            if (modelRoot != null)
            {
                model.transform.SetParent(modelRoot, false);
            }

            var playerDefaultEquipments = model.GetComponentInChildren<PlayerDefaultEquipments>();
            if (playerDefaultEquipments == null)
            {
                return null;
            }

            DATA_TYPE DataType = default;
            bool useDefaultUpper = true;
            bool useDefaultLower = true;
            bool useDefaultWrist = true;
            bool useDefaultFoot = true;

            GRoleInventory equipment;

            for (int i = 0; i < role.equipment.Count; i++)
            {
                equipment = role.equipment[i];

                var equipData = elemendataman.get_data_ptr((uint)equipment.id, ID_SPACE.ID_SPACE_ESSENCE, ref DataType);

                switch (DataType)
                {
                    case DATA_TYPE.DT_WEAPON_ESSENCE:
                        if (equipData == null) break;
                        var weaponData = (WEAPON_ESSENCE)equipData;

                        string fileModelRight = AFile.NormalizePath(weaponData.FileModelRight, true).ToLower();
                        string fileModelLeft = AFile.NormalizePath(weaponData.FileModelLeft, true).ToLower();

                        GameObject weaponPrefab = null;
                        if (!string.IsNullOrEmpty(fileModelRight))
                        {
                            weaponPrefab = await AddressableManager.Instance.LoadPrefabAsync(fileModelRight);
                            var weaponObject = Instantiate(weaponPrefab);
                            if (weaponObject != null)
                            {
                                weaponObject.transform.SetParent(FindChildObjectRecursive(model.transform, CECPlayer._hh_right_hand_weapon).transform);
                                weaponObject.transform.localPosition = weaponPrefab.transform.localPosition;
                                weaponObject.transform.localRotation = weaponPrefab.transform.localRotation;
                                weaponObject.transform.localScale = Vector3.one;
                                weaponObject.SetActive(true);
                            }
                        }

                        if (!string.IsNullOrEmpty(fileModelLeft))
                        {
                            weaponPrefab = await AddressableManager.Instance.LoadPrefabAsync(fileModelLeft);
                            var weaponObject = Instantiate(weaponPrefab);
                            if (weaponObject != null)
                            {
                                weaponObject.transform.SetParent(FindChildObjectRecursive(model.transform, CECPlayer._hh_left_hand_weapon).transform);
                                weaponObject.transform.localPosition = weaponPrefab.transform.localPosition;
                                weaponObject.transform.localRotation = weaponPrefab.transform.localRotation;
                                weaponObject.transform.localScale = Vector3.one;
                                weaponObject.SetActive(true);
                            }
                        }
                        break;
                    case DATA_TYPE.DT_ARMOR_ESSENCE:
                        if (equipData == null) break;
                        var pArmor = (ARMOR_ESSENCE)equipData;
                        var nLocation = pArmor.equip_location;

                        var armorSkinPath = CECPlayer._GenEquipmentSkinPath(role.occupation, role.gender, pArmor.RealName);
                        if (!armorSkinPath.EndsWith(".ecm"))
                        {
                            armorSkinPath += ".ecm";
                        }
                        var armorPrefab = await AddressableManager.Instance.LoadPrefabAsync(armorSkinPath);
                        if (armorPrefab != null)
                        {
                            var armorObject = Instantiate(armorPrefab);
                            armorObject.transform.SetParent(GetSkeletonBuilder(model)?.transform);
                            armorObject.transform.localPosition = Vector3.zero;
                            armorObject.transform.localRotation = Quaternion.identity;
                            armorObject.transform.localScale = Vector3.one;

                            var skinnedMeshRenderereFromDataList = armorObject.GetComponentsInChildren<SkinnedMeshRenderFromData>();
                            foreach (var skinnedMeshRenderereFromData in skinnedMeshRenderereFromDataList)
                            {
                                if (skinnedMeshRenderereFromData != null)
                                {
                                    skinnedMeshRenderereFromData._skinnedMeshRenderer.bones = GetSkeletonBuilder(model).GetBones(skinnedMeshRenderereFromData.BoneNames);
                                    skinnedMeshRenderereFromData._skinnedMeshRenderer.rootBone = skinnedMeshRenderereFromData._skinnedMeshRenderer.bones[^1];
                                }
                            }

                            switch (nLocation)
                            {
                                case (uint)CECPlayer.SkinIndex.SKIN_UPPER_BODY_INDEX:
                                    useDefaultUpper = false;
                                    break;
                                case (uint)CECPlayer.SkinIndex.SKIN_LOWER_INDEX:
                                    useDefaultLower = false;
                                    break;
                                case (uint)CECPlayer.SkinIndex.SKIN_WRIST_INDEX:
                                    useDefaultWrist = false;
                                    break;
                                case (uint)CECPlayer.SkinIndex.SKIN_FOOT_INDEX:
                                    useDefaultFoot = false;
                                    break;
                            }
                        }
                        break;
                }

                switch (equipment.pos)
                {
                    case InventoryConst.EQUIPIVTR_BODY:
                        useDefaultUpper = false;
                        break;
                    case InventoryConst.EQUIPIVTR_LEG:
                        useDefaultLower = false;
                        break;
                    case InventoryConst.EQUIPIVTR_WRIST:
                        useDefaultWrist = false;
                        break;
                    case InventoryConst.EQUIPIVTR_FOOT:
                        useDefaultFoot = false;
                        break;
                }
            }

            playerDefaultEquipments.DefaultUpper.SetActive(useDefaultUpper);
            playerDefaultEquipments.DefaultLower.SetActive(useDefaultLower);
            playerDefaultEquipments.DefaultWirst.SetActive(useDefaultWrist);
            playerDefaultEquipments.DefaultFoot.SetActive(useDefaultFoot);
            return model;
        }

        private GameObject FindChildObjectRecursive(Transform parent, string name)
        {
            foreach (Transform child in parent)
            {
                if (child.name == name)
                {
                    return child.gameObject;
                }

                var childObject = FindChildObjectRecursive(child, name);
                if (childObject != null)
                {
                    return childObject;
                }
            }

            return null;
        }

        private SkeletonBuilder GetSkeletonBuilder(GameObject characterModel)
        {
            if (characterModel == null)
            {
                return null;
            }

            return characterModel.GetComponentInChildren<SkeletonBuilder>();
        }

        public void ReloadRoleModel(RoleInfo roleInfo)
        {
            if (roleInfo == null)
                return;

            _lastPreviewRoleInfo = roleInfo;
            _suppressHierarchyWatch = true;
            ShowAllPlayerModels(new List<RoleInfo> { roleInfo }).Forget();
            ShowPlayerModel(roleInfo.roleid);
        }

        private Transform GetActivePreviewModelTransform()
        {
            if (!_hasRequestedPlayerModelId)
                return null;

            int n = Mathf.Min(playerModels.Count, playerModelIds.Count);
            for (int i = 0; i < n; i++)
            {
                GameObject model = playerModels[i];
                if (model != null && model.activeSelf && playerModelIds[i] == _requestedPlayerModelId)
                    return model.transform;
            }

            for (int i = 0; i < n; i++)
            {
                GameObject model = playerModels[i];
                if (model != null && playerModelIds[i] == _requestedPlayerModelId)
                    return model.transform;
            }

            return null;
        }

        private void TryRefreshFromCachedRole()
        {
            if (_lastPreviewRoleInfo == null || !_inventoryPreviewActive || _suppressHierarchyWatch)
                return;

            ReloadRoleModel(_lastPreviewRoleInfo);
        }

        private void SyncHierarchyBaseline()
        {
            Transform activeRoot = GetActivePreviewModelTransform();
            if (activeRoot == null)
                return;

            _lastOriginModelRoot = activeRoot;
            _lastOriginModelChildCount = CountAllChildren(activeRoot);
        }

        private void ResetHierarchyWatch()
        {
            _lastOriginModelRoot = null;
            _lastOriginModelChildCount = 0;
        }

        private static int CountAllChildren(Transform root)
        {
            if (root == null)
                return 0;

            int count = root.childCount;
            for (int i = 0; i < root.childCount; i++)
            {
                count += CountAllChildren(root.GetChild(i));
            }

            return count;
        }
    }
}