using UnityEngine;
using UnityEngine.UI;
using TMPro;
using System.Collections.Generic;
using LLM;

namespace UI
{
    public class ChatHistoryPanelController : MonoBehaviour
    {
        [Header("UI References")]
        public Transform historyContent;     // 历史记录的父物体 (ScrollView Content)
        public GameObject messagePrefab;     // 聊天气泡预设体，可复用 AssistPanel 的

        [Header("Manager")]
        public LLMChatManager chatManager;   // 引用 LLMChatManager

        private void OnEnable()
        {
            if (chatManager == null)
            {
                chatManager = FindObjectOfType<LLMChatManager>();
            }

            if (chatManager != null)
            {
                RefreshHistoryUI();
            }
            else
            {
                Debug.LogWarning("[ChatHistoryPanelController] LLMChatManager is missing!");
            }
        }

        public void RefreshHistoryUI()
        {
            if (historyContent == null || messagePrefab == null) return;

            // 清理旧的记录
            foreach (Transform child in historyContent)
            {
                Destroy(child.gameObject);
            }

            // 获取全部历史记录
            List<Message> fullLog = chatManager.fullChatLog;
            if (fullLog == null || fullLog.Count == 0) return;

            // 遍历并生成气泡
            foreach (var msg in fullLog)
            {
                // 过滤掉 system 提示词等，只显示玩家和 AI 的对话
                if (msg.role == "user" || msg.role == "assistant")
                {
                    bool isPlayer = (msg.role == "user");
                    AddMessageToUI(msg.content, isPlayer);
                }
            }

            // 强制更新 Canvas 以确保布局正确，然后滚动到底部
            Canvas.ForceUpdateCanvases();
            ScrollRect scrollRect = historyContent.GetComponentInParent<ScrollRect>();
            if (scrollRect != null)
            {
                scrollRect.verticalNormalizedPosition = 0f;
            }
        }

        private void AddMessageToUI(string text, bool isPlayer)
        {
            GameObject newMsg = Instantiate(messagePrefab, historyContent);
            TextMeshProUGUI tmp = newMsg.GetComponentInChildren<TextMeshProUGUI>();
            
            if (tmp != null)
            {
                tmp.text = text; 
            }

            var aligner = newMsg.GetComponent<MessageAligner>();
            if (aligner != null)
            {
                aligner.SetAlignment(isPlayer);
            }
        }
    }
}