using UnityEngine;
using UnityEngine.UI;
using TMPro;
using System.Collections;
using System.Collections.Generic;
using LLM; // 引用新的 LLM 命名空间
using Core.InputLock;

namespace UI
{
    public class TabletController : MonoBehaviour
    {
        [SerializeField] private bool debugLogs = true;
        [Header("UI References")]
        public GameObject tabletPanel;       // 整个平板界面的父物体
        public TMP_InputField inputField;    // 输入框
        public Transform chatContent;        // 聊天记录的父物体 (ScrollView Content)
        public GameObject messagePrefab;     // 聊天气泡预设体
        
        [Header("Game Control")]
        public GameObject hudCanvas;         // 游戏原本的 HUD (准星等)，打开平板时隐藏
        public MonoBehaviour playerController; // 玩家控制器脚本

        [Header("LLM Manager")]
        public LLMChatManager chatManager;   // 引用 LLMChatManager 来管理多模型切换
        // public GameObject llmServiceObj;  // 已废弃，请使用 chatManager

        private Coroutine rebuildChatLayoutRoutine;

        public static TabletController Instance { get; private set; }

        private void Awake()
        {
            if (Instance == null) Instance = this;
            else Destroy(gameObject);

            if (tabletPanel != null) tabletPanel.SetActive(false);

            if (playerController == null)
            {
                playerController = FindObjectOfType<Player.PlayerController>(true);
            }
            
            // 自动查找 LLMChatManager (如果在场景中)
            if (chatManager == null)
            {
                chatManager = FindObjectOfType<LLMChatManager>();
            }
            
            if (chatManager == null)
            {
                Debug.LogError("[TabletController] 未找到 LLMChatManager！请确保场景中存在该管理器。");
            }
            else
            {
                // 监听历史记录加载完成（这里简单地在 Start 中延迟一帧加载，因为 SaveManager 加载通常很快）
                StartCoroutine(InitChatHistory());
            }
        }

        private IEnumerator InitChatHistory()
        {
            // 等待一帧，确保 LLMChatManager 已经完成了 Start 中的 SaveManager.LoadGame()
            yield return null;

            if (chatManager.fullChatLog != null && chatManager.fullChatLog.Count > 0)
            {
                // 清理可能存在的测试数据（如果有）
                foreach (Transform child in chatContent)
                {
                    Destroy(child.gameObject);
                }

                // 重建 UI
                foreach (var msg in chatManager.fullChatLog)
                {
                    bool isPlayer = (msg.role == "user");
                    // 只有 user 和 assistant 的消息需要显示
                    if (msg.role == "user" || msg.role == "assistant")
                    {
                        AddMessageToUI(isPlayer ? "Player" : "AI", msg.content, isPlayer);
                    }
                }
                
                // 滚动到底部
                yield return new WaitForEndOfFrame();
                ScrollRect scrollRect = chatContent.GetComponentInParent<ScrollRect>();
                if (scrollRect != null) scrollRect.verticalNormalizedPosition = 0f;
            }
        }

    public void ShowTablet()
    {
        if (debugLogs) Debug.Log("[TabletController] ShowTablet");
        if (tabletPanel != null) tabletPanel.SetActive(true);
        if (hudCanvas != null) hudCanvas.SetActive(false);

        TogglePlayerControl(false);

        Cursor.lockState = CursorLockMode.None;
        Cursor.visible = true;

        if (inputField != null) inputField.ActivateInputField();

        if (rebuildChatLayoutRoutine != null) StopCoroutine(rebuildChatLayoutRoutine);
        rebuildChatLayoutRoutine = StartCoroutine(RebuildChatLayoutNextFrame());

        if (UI.PanelStack.UIPanelStack.Instance != null && tabletPanel != null)
        {
            UI.PanelStack.UIPanelStack.Instance.Push(UI.PanelStack.UIPanelKind.Custom, tabletPanel, HideTablet);
        }
    }

    public void HideTablet()
    {
        if (debugLogs) Debug.Log("[TabletController] HideTablet");
        if (tabletPanel != null) tabletPanel.SetActive(false);
        if (hudCanvas != null) hudCanvas.SetActive(true);

        TogglePlayerControl(true);

        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;

        if (UI.PanelStack.UIPanelStack.Instance != null && tabletPanel != null)
        {
            UI.PanelStack.UIPanelStack.Instance.Remove(tabletPanel);
        }
    }

    private void TogglePlayerControl(bool enable)
    {
        if (PlayerControlLockService.Instance != null)
        {
            if (enable) { PlayerControlLockService.Instance.Unlock(this); }
            else { PlayerControlLockService.Instance.Lock(this); }
        }

        if (playerController != null) playerController.enabled = enable;
    }

    public void OnSendClicked()
    {
        if (inputField == null || string.IsNullOrWhiteSpace(inputField.text)) return;
        if (chatManager == null) 
        {
            AddMessageToUI("System", "LLM 服务管理器未连接。", true);
            return;
        }

        string userMessage = inputField.text;
        inputField.text = "";

        AddMessageToUI("Player", userMessage, true);

        // 使用 LLMChatManager 发送消息，它会自动选择当前激活的服务
        chatManager.SendUserMessage(userMessage, (reply, success) => 
        {
            AddMessageToUI("AI", reply, false);
        });
    }

    private void AddMessageToUI(string role, string text, bool isPlayer)
    {
        if (messagePrefab == null || chatContent == null) return;

        GameObject newMsg = Instantiate(messagePrefab, chatContent);
        TextMeshProUGUI tmp = newMsg.GetComponentInChildren<TextMeshProUGUI>();
        
        if (tmp != null)
        {
            tmp.text = text; 
        }

        var aligner = newMsg.GetComponent<MessageAligner>();
        if (aligner != null)
        {
            aligner.SetAlignment(isPlayer);
        }
        
        // 限制 UI 显示数量，防止无限增加导致卡顿 (保留最近的 50 条)
        int maxUIItems = 50;
        if (chatContent.childCount > maxUIItems)
        {
            Destroy(chatContent.GetChild(0).gameObject);
        }
        
        Canvas.ForceUpdateCanvases();
        ScrollRect scrollRect = chatContent.GetComponentInParent<ScrollRect>();
        if (scrollRect != null) scrollRect.verticalNormalizedPosition = 0f;
    }

    private IEnumerator RebuildChatLayoutNextFrame()
    {
        yield return new WaitForEndOfFrame();

        if (chatContent == null) yield break;

        foreach (Transform child in chatContent)
        {
            var aligner = child.GetComponent<MessageAligner>();
            if (aligner != null) aligner.Reapply();
        }

        Canvas.ForceUpdateCanvases();

        RectTransform chatContentRect = chatContent as RectTransform;
        if (chatContentRect != null) LayoutRebuilder.ForceRebuildLayoutImmediate(chatContentRect);

        ScrollRect scrollRect = chatContent.GetComponentInParent<ScrollRect>();
        if (scrollRect != null) scrollRect.verticalNormalizedPosition = 0f;
    }
    }
}