using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using BrewMonster.Network;
using BrewMonster.Scripts;
using CSNetwork.Protocols;
using CSNetwork.Protocols.RPCData;
using TMPro;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

namespace BrewMonster.UI
{
    /// <summary>
    /// Login Flow:
    /// 1. Enter username and password
    /// 2. Click login button
    /// 3. Login success, get the list of characters
    /// 4. Open the select character screen
    /// </summary>
    public class LoginScreenUI : MonoBehaviour
    {
        [SerializeField] private TMP_InputField _usernameInputField;
        [SerializeField] private TMP_InputField _passwordInputField;
        [SerializeField] private Button _loginButton;
        [SerializeField] private SelecScreenCharacter _selectCharacterScreen;

        private List<RoleInfo> _roleInfos;
        private List<RoleInfo> _currentRoles;
        private RoleInfo _pendingCreatedRole;
        private bool _loginInProgress;
        bool isDoneWorldRender = false;
        bool isDoneNPCRender = false;
        private SynchronizationContext context;
        [Header("Audio")]
        [Tooltip("Set 3 clips to pick a random login theme.")]
        [SerializeField] private AudioClip[] _loginBGMs;

        void Awake()
        {
            // Ensure wrapper created early (Tech3C SDK).
            _ = Tech3CSDKWrapper.Instance;

            #if UNITY_EDITOR
            _usernameInputField.gameObject.SetActive(true);
            _passwordInputField.gameObject.SetActive(true);
            #else
            _usernameInputField.gameObject.SetActive(false);
            _passwordInputField.gameObject.SetActive(false);
            #endif
        }

        void OnEnable()
        {
            Tech3CSDKWrapper.Instance.SetLoginCallback(OnLoginCallback);
            Tech3CSDKWrapper.Instance.SetLogoutCallback(OnLogoutCallback);
        }

        private void OnDisable()
        {
            Tech3CSDKWrapper.Instance.RemoveLoginCallback();
            Tech3CSDKWrapper.Instance.RemoveLogoutCallback();
        }

        void Start()
        {
            var chosenBgm = PickLoginBGM();
            if (chosenBgm != null && AudioManager.Instance != null)
            {
                AudioManager.Instance.PlayBGM(chosenBgm, 1.5f);
            }
            _loginButton.onClick.AddListener(OnLoginButtonClicked);
            context = SynchronizationContext.Current;
#if UNITY_EDITOR
            // only load the username and password from the player prefs if in editor
            _usernameInputField.text = PlayerPrefs.GetString("username", "");
            _passwordInputField.text = PlayerPrefs.GetString("password", "");
#endif

            // Default: login UI first, select-role hidden until login succeeds.
            if (_selectCharacterScreen != null)
                _selectCharacterScreen.gameObject.SetActive(false);

            // ApplyLoginEntry(LogoutFlowState.ConsumeNextLoginEntry());
        }

        private AudioClip PickLoginBGM()
        {
            if (_loginBGMs != null && _loginBGMs.Length > 0)
            {
                // UnityEngine.Random is deterministic per session and good enough here.
                int idx = UnityEngine.Random.Range(0, _loginBGMs.Length);
                return _loginBGMs[idx];
            }
            return null;
        }

        // Update is called once per frame
        void Update()
        {
            if (_roleInfos != null)
            {
                _selectCharacterScreen.InitScreen(_roleInfos, OnClickSelectCharacter, OnCreateCharacterComplete);
                _roleInfos = null;
            }

#if UNITY_EDITOR
            if (Input.GetKeyUp(KeyCode.LeftAlt))
            {
                _usernameInputField.text = "test016";
                _passwordInputField.text = "123456";
                OnLoginButtonClicked();
            }

            if (Input.GetKeyUp(KeyCode.Tab))
            {
                _usernameInputField.text = "test017";
                _passwordInputField.text = "123456";
                OnLoginButtonClicked();
            }
#endif
        }


        public async void OnLoginButtonClicked()
        {
            if (_loginInProgress)
            {
                BMLogger.LogWarning("[LoginScreenUI] Login already in progress (ignored click).");
                return;
            }

            _loginInProgress = true;
            if (_loginButton != null) _loginButton.interactable = false;

            // If username or password is empty, use Tech3C SDK login UI.
            if (string.IsNullOrEmpty(_usernameInputField.text) || string.IsNullOrEmpty(_passwordInputField.text))
            {
                // Use Tech3C SDK login UI.
                bool started = Tech3CSDKWrapper.Instance.Login();
                if (!started)
                {
                    // Fallback: manual username/password login (useful in dev if SDK not configured).
                    BMLogger.LogWarning("[LoginScreenUI] Tech3CSDKWrapper.Login() failed, fallback to manual login.");
                    await BeginGameLoginAsync(_usernameInputField.text, _passwordInputField.text);
                }
            }
            else
            {
                // otherwise use manual username/password login.
                BMLogger.LogError("[LoginScreenUI] Username/password empty.");
                await BeginGameLoginAsync(_usernameInputField.text, _passwordInputField.text);
            }

        }

        private async Task BeginGameLoginAsync(string username, string password)
        {
            if (string.IsNullOrEmpty(username) || string.IsNullOrEmpty(password))
            {
                BMLogger.LogError("[LoginScreenUI] Username/password empty.");
                _loginInProgress = false;
                if (_loginButton != null) _loginButton.interactable = true;
                return;
            }

            BMLogger.Log("OnLoginButtonClicked");
            UnityGameSession.SetConnectionInfo("103.51.120.195", 29000);
            PlayerPrefs.SetString("username", username);
            PlayerPrefs.SetString("password", password);
            PlayerPrefs.Save();

            BMLogger.Log($"[LoginScreenUI] Connecting+login start user='{username}'");
            await UnityGameSession.Login(username, password, OnLoginComplete);
        }

        // NOTE: Previously had an ApplyLoginEntry helper that referenced LogoutFlowState.
        // It was unused and caused build/lint issues on some platforms, so it's been removed.

        /// <summary>
        /// Callback when the login is complete.
        /// Then get the list of characters
        /// </summary>
        private void OnLoginComplete(bool result)
        {
            BMLogger.Log($"[LoginScreenUI] OnLoginComplete result={result}");
            if (!result)
            {
                BMLogger.LogError("Login failed");
                if (_selectCharacterScreen != null)
                    _selectCharacterScreen.gameObject.SetActive(false);
                _loginInProgress = false;
                if (_loginButton != null) _loginButton.interactable = true;
                return;
            }

            if (_selectCharacterScreen != null)
                _selectCharacterScreen.gameObject.SetActive(true);
            UnityGameSession.GetRoleListAsync(OnGetRoleListComplete);
        }

        /// <summary>
        /// Callback when the list of characters is retrieved.
        /// Then move to the select character screen
        /// </summary>
        private void OnGetRoleListComplete(List<RoleInfo> roleInfos)
        {
            if (roleInfos == null)
            {
                BMLogger.LogError("OnGetRoleListComplete: roleInfos is null");
                // Keep whatever is currently shown; don't overwrite UI state with null.
                _loginInProgress = false;
                if (_loginButton != null) _loginButton.interactable = true;
                return;
            }

            // Merge pending created role in case backend list hasn't updated yet.
            if (_pendingCreatedRole != null)
            {
                bool exists = false;
                for (int i = 0; i < roleInfos.Count; i++)
                {
                    if (roleInfos[i].roleid == _pendingCreatedRole.roleid)
                    {
                        exists = true;
                        break;
                    }
                }

                if (!exists)
                {
                    // Copy list so we don't mutate a list owned elsewhere.
                    var merged = new List<RoleInfo>(roleInfos.Count + 1);
                    merged.AddRange(roleInfos);
                    merged.Add(_pendingCreatedRole);
                    roleInfos = merged;
                }
                else
                {
                    // Backend now includes the role; clear pending.
                    _pendingCreatedRole = null;
                }
            }

            BMLogger.Log($"OnGetRoleListComplete: roles={roleInfos.Count}");
            _roleInfos = roleInfos;
            _currentRoles = roleInfos;

            // Login flow finished; keep login button disabled (origin-like) once you're at select role.
            _loginInProgress = false;
        }

        private void OnClickSelectCharacter(RoleInfo roleInfo)
        {
            LoadingSceneController.Instance.ShowLoadingScene(true);
            UnityGameSession.SelectRoleAsync(roleInfo, OnSelectRoleComplete);
        }

        /// <summary>
        /// Callback when a new character is created.
        /// Refreshes the role list and keeps the character selection screen visible.
        /// </summary>
        private void OnCreateCharacterComplete(RoleInfo createdRole)
        {
            BMLogger.Log("Character created, refreshing role list...");
            if (_selectCharacterScreen != null)
            {
                _selectCharacterScreen.gameObject.SetActive(true);
            }

            // Ensure the newly created role is visible immediately even if the server role list
            // hasn't updated yet.
            if (createdRole != null)
            {
                _pendingCreatedRole = createdRole;
                if (_currentRoles == null)
                {
                    _currentRoles = new List<RoleInfo>();
                }

                bool exists = false;
                for (int i = 0; i < _currentRoles.Count; i++)
                {
                    if (_currentRoles[i].roleid == createdRole.roleid)
                    {
                        exists = true;
                        break;
                    }
                }

                if (!exists)
                {
                    _currentRoles.Add(createdRole);
                }

                _roleInfos = _currentRoles;
            }
            else
            {
                BMLogger.LogError("OnCreateCharacterComplete: createdRole is null (create-role callback returned null)");
            }

            // NOTE:
            // Immediately requesting the role list after create has been observed to disconnect
            // in some server builds. We rely on the createdRole callback to update UI instantly.
            // A server sync can be done later (e.g., next time you open this screen / re-login).
        }

        private void OnSelectRoleComplete(RoleInfo roleInfo)
        {
            context.Post(_ =>
            {
                isDoneWorldRender = false;
                isDoneNPCRender = false;
                Action actLoadChar = () =>
                {
                    if (!isDoneNPCRender || !isDoneWorldRender)
                    {
                        return;
                    }
                };
                SceneLoader.SceneLoadProcess = SceneLoadProcess.Loading;
                SceneLoader.LoadingProgress = 0;
#if TESTFAST
                string nameScene = "LoginScene";
                SceneManager.UnloadSceneAsync(nameScene);
                isDoneNPCRender = true;
                isDoneWorldRender = true;
                actLoadChar?.Invoke();
                UnityGameSession.EnterWorldAsync(roleInfo, OnEnterWorldComplete);
#else
                string nameScene = UnityGameSession.Instance.GetWorldInstanceName();
                UnityGameSession.Instance.LoadScene(nameScene, LoadSceneMode.Single,
                (progress) =>
                {
                    LoadingSceneController.Instance.SetProgress(progress);
                },
                (value) =>
                {
                    isDoneWorldRender = value;
                    isDoneNPCRender = true;
                    isDoneWorldRender = true;
                    actLoadChar?.Invoke();
                    AudioManager.Instance.StopBGM(1f);
                    WorldMusicController.Instance.InitForWorld(roleInfo.worldtag);
                    UnityGameSession.EnterWorldAsync(roleInfo, OnEnterWorldComplete);
                });
#endif
            }, null);
        }

        private async void OnEnterWorldComplete()
        {
            await Task.Delay(2000);
            // Request all known packages: 0=Inventory,1=Equipment,2=Task
            UnityGameSession.RequestAllInventoriesAsync(() => { /*BMLogger.Log("Sent Inventory Detail Requests (all packs)");*/ }, 0, 1, 2);
            await Task.Delay(1000);
            UnityGameSession.RequestCheckSecurityPassWd("");
            // C++ friend_GetList(); required before Add Friend
            await Task.Delay(1000);
            UnityGameSession.Friend_GetList();
        }

        //private void OnInventoryReceived(List<InventoryItem> inventoryData)
        //{
        //    _inventoryUI.DisplayInventory(inventoryData);
        //}

#if UNITY_EDITOR
        private void OnValidate()
        {
            if (_usernameInputField == null)
            {
                // find childrend with name "username"
                _usernameInputField = transform.Find("username").GetComponent<TMP_InputField>();
            }

            if (_passwordInputField == null)
            {
                // find childrend with name "password"
                _passwordInputField = transform.Find("password").GetComponent<TMP_InputField>();
            }

            if (_loginButton == null)
            {
                // find childrend with name "LoginBtn"
                _loginButton = transform.Find("LoginBtn").GetComponent<Button>();
            }
        }
#endif

        private async void OnLoginCallback(int errorCode, string userId, string password)
        {
            if (errorCode == 0)
            {
                BMLogger.Log($"Login success -- userId: {userId} - {password}");
                // UnityGameSession.SetConnectionInfo("103.182.22.52", 29000);
                UnityGameSession.SetConnectionInfo("103.51.120.195", 29000);
                PlayerPrefs.SetString("username", userId);
                PlayerPrefs.SetString("password", password);
                PlayerPrefs.Save();
                await BeginGameLoginAsync(userId, password);
            }
            else
            {
                // if it failed, the userId will be the error message
                BMLogger.LogError($"Login failed -- errorCode: {errorCode}: {userId}");
                _loginInProgress = false;
                if (_loginButton != null) _loginButton.interactable = true;
            }
        }

        private void OnLogoutCallback(int errorCode, string errorMessage)
        {
            if (errorCode == 0)
            {
                BMLogger.Log("Logout success");
            }
            else
            {
                BMLogger.LogError($"Logout failed -- errorCode: {errorCode}: {errorMessage}");
            }
        }
    }
}