using System.Collections.Generic;
using GameFramework.Event;
using UnityGameFramework.Runtime;

namespace UI
{
    public sealed class AIChatEntryFormController : IFormController<AIChatEntryFormContext>
    {
        private AIChatEntryFormContext _entryContext;
        private AIChatEntryForm _entryForm;
        private int? _entryFormSerialId;
        private bool _pendingEntryRefresh;

        private AIChatFormController _chatFormController;
        private AIChatFormContext _chatContext;

        public AIChatEntryFormController()
        {
            GameEntry.Event.Subscribe(OpenUIFormSuccessEventArgs.EventId, OnOpenUIFormSuccess);
            GameEntry.Event.Subscribe(CloseUIFormCompleteEventArgs.EventId, OnCloseUIFormComplete);
        }

        ~AIChatEntryFormController()
        {
            GameEntry.Event.Unsubscribe(OpenUIFormSuccessEventArgs.EventId, OnOpenUIFormSuccess);
            GameEntry.Event.Unsubscribe(CloseUIFormCompleteEventArgs.EventId, OnCloseUIFormComplete);
        }

        public int? OpenUI(AIChatEntryFormContext context)
        {
            if (context == null)
            {
                Log.Warning("AIChatEntryFormController open failed. context is null.");
                return null;
            }

            context.Controller = this;
            _entryContext = context;
            SyncEntryContextState();

            if (_entryForm != null)
            {
                _entryForm.RefreshUI(_entryContext);
                return _entryFormSerialId;
            }

            UGuiForm openedForm = GameEntry.UI.GetUIForm(UIFormId.AIChatEntryForm);
            if (openedForm is AIChatEntryForm existingForm)
            {
                _entryForm = existingForm;
                _entryFormSerialId = existingForm.UIForm.SerialId;
                _entryForm.RefreshUI(_entryContext);
                return _entryFormSerialId;
            }

            _pendingEntryRefresh = true;
            _entryFormSerialId = GameEntry.UI.OpenUIForm(UIFormId.AIChatEntryForm, _entryContext);
            return _entryFormSerialId;
        }

        public void CloseUI()
        {
            _pendingEntryRefresh = false;

            if (_entryFormSerialId.HasValue)
            {
                GameEntry.UI.CloseUIForm(_entryFormSerialId.Value);
                return;
            }

            if (_entryForm != null)
            {
                _entryForm.Close();
            }
        }

        public void ToggleAIChatForm()
        {
            UGuiForm openedChatForm = GameEntry.UI.GetUIForm(UIFormId.AIChatForm);
            if (openedChatForm != null)
            {
                if (_chatFormController != null)
                {
                    _chatFormController.CloseUI();
                }
                else
                {
                    GameEntry.UI.CloseUIForm(openedChatForm.UIForm);
                }

                RefreshEntryState();
                return;
            }

            EnsureChatContext();
            _chatContext.Controller = _chatFormController;
            _chatFormController.OpenUI(_chatContext);
            RefreshEntryState();
        }

        private void EnsureChatContext()
        {
            if (_chatFormController == null)
            {
                _chatFormController = new AIChatFormController();
            }

            if (_chatContext == null)
            {
                _chatContext = new AIChatFormContext
                {
                    ClearHistoryOnOpen = false,
                    LanguageMode = 0,
                    Messages = new List<AIChatMessageContext>()
                };
            }

            _chatContext.Controller = _chatFormController;
            _chatContext.Messages ??= new List<AIChatMessageContext>();
        }

        private void SyncEntryContextState()
        {
            if (_entryContext == null)
            {
                return;
            }

            _entryContext.IsChatOpened = GameEntry.UI.GetUIForm(UIFormId.AIChatForm) != null;
        }

        private void RefreshEntryState()
        {
            SyncEntryContextState();

            if (_entryForm == null || _entryContext == null)
            {
                return;
            }

            _entryForm.SetChatOpened(_entryContext.IsChatOpened);
        }

        private void OnOpenUIFormSuccess(object sender, GameEventArgs e)
        {
            if (!(e is OpenUIFormSuccessEventArgs args))
            {
                return;
            }

            if (_entryFormSerialId.HasValue &&
                args.UIForm != null &&
                args.UIForm.SerialId == _entryFormSerialId.Value &&
                args.UserData == _entryContext)
            {
                _entryForm = args.UIForm.Logic as AIChatEntryForm;
                if (_entryForm == null)
                {
                    Log.Warning("AIChatEntryFormController open success but form logic is invalid.");
                }
                else if (_pendingEntryRefresh)
                {
                    _entryForm.RefreshUI(_entryContext);
                    _pendingEntryRefresh = false;
                }
            }

            RefreshEntryState();
        }

        private void OnCloseUIFormComplete(object sender, GameEventArgs e)
        {
            if (!(e is CloseUIFormCompleteEventArgs args))
            {
                return;
            }

            if (args.SerialId == _entryFormSerialId)
            {
                _entryForm = null;
                _entryFormSerialId = null;
                _pendingEntryRefresh = false;
            }

            RefreshEntryState();
        }
    }
}