using System;
using System.Collections;
using System.Collections.Generic;
using LLM;
using Michsky.UI.Reach;
using TMPro;
using UnityEngine;
using UnityEngine.Serialization;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

namespace UI.Ending
{
    public class EndingUIScreenController : MonoBehaviour
    {
        [SerializeField] private bool debugLogs = true;

        public enum EndingOutcome
        {
            Escaped,
            Fainted
        }

        [Header("Scene")]
        [SerializeField] private int mainMenuSceneBuildIndex = 1;
        [SerializeField] private bool beginPreloadOnEnable = true;

        [Header("UI")]
        [FormerlySerializedAs("summaryText")]
        [SerializeField] private TMP_Text summarayText;
        [SerializeField] private TMP_Text informationText;
        [SerializeField] private string requestingText = "正在生成总结...";

        [Header("Information Text")]
        [SerializeField] private EndingOutcome outcome = EndingOutcome.Escaped;
        [SerializeField] private bool applyOutcomeTextOnEnable = true;
        [TextArea]
        [SerializeField] private string escapedInformationString = "（成功逃离时的提示词，自己填写）";
        [TextArea]
        [SerializeField] private string faintedInformationString = "（倒下/昏倒时的提示词，自己填写）";

        [Header("Buttons")]
        [SerializeField] private ButtonManager returnToMenuButton;
        [SerializeField] private Button returnToMenuButtonUGUI;

        [Header("AI Summary")]
        [SerializeField] private bool requestAISummaryOnEnable = true;
        [SerializeField] private LLMChatManager chatManager;
        [SerializeField] private int maxHistoryMessages = 30;
        [SerializeField] private bool includeKnownFactsFromContextMemory = true;
        [TextArea]
        [SerializeField] private string summarySystemPrompt = "你是一个游戏结局总结助手。你需要根据对话历史与已知事实，生成一段简短的结局总结，面向玩家。";
        [TextArea]
        [SerializeField] private string summaryUserPromptTemplate =
            "请为玩家生成结局总结。\n" +
            "要求：\n" +
            "- 80~160 字\n" +
            "- 只输出严格 JSON：{\"summary\":\"...\"}\n" +
            "- 不要输出代码块，不要多余字段\n\n" +
            "已知事实：\n{KNOWN_FACTS}\n\n" +
            "对话历史：\n{CHAT_HISTORY}\n";

        [Header("AI Summary Debug")]
        [SerializeField] private ButtonManager debugSummaryButton;
        [SerializeField] private Button debugSummaryButtonUGUI;
        [TextArea]
        [SerializeField] private string debugSummaryString = "（这里是预设的 Debug 总结字符串）";

        private AsyncOperation preloadOperation;
        private bool isWired;
        private Coroutine summaryCoroutine;

        [Serializable]
        private class SummaryResponse
        {
            public string summary;
        }

        private void Awake()
        {
            if (summarayText == null) { summarayText = FindTMPByNameHint("Summaray", "Summary"); }
            if (informationText == null) { informationText = FindTMPByNameHint("Information", "Info"); }

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

            WireOnce();
        }

        private void OnEnable()
        {
            WireOnce();

            if (beginPreloadOnEnable)
            {
                BeginPreloadMainMenu();
            }

            if (applyOutcomeTextOnEnable)
            {
                ApplyOutcomeInformationText();
            }

            if (requestAISummaryOnEnable)
            {
                GenerateSummaryWithAI();
            }
        }

        public void BeginPreloadMainMenu()
        {
            if (preloadOperation != null) { return; }

            if (mainMenuSceneBuildIndex < 0 || mainMenuSceneBuildIndex >= SceneManager.sceneCountInBuildSettings)
            {
                if (debugLogs) Debug.Log($"[EndingUI] Invalid mainMenuSceneBuildIndex={mainMenuSceneBuildIndex}");
                return;
            }

            StartCoroutine(PreloadRoutine());
        }

        private IEnumerator PreloadRoutine()
        {
            preloadOperation = SceneManager.LoadSceneAsync(mainMenuSceneBuildIndex);
            if (preloadOperation == null) { yield break; }

            preloadOperation.allowSceneActivation = false;

            while (preloadOperation.progress < 0.9f)
            {
                yield return null;
            }

            if (debugLogs) Debug.Log("[EndingUI] Main menu preload ready (progress>=0.9).");
        }

        private bool IsPreloadReady()
        {
            return preloadOperation != null && preloadOperation.progress >= 0.9f;
        }

        public void ReturnToMainMenu()
        {
            if (mainMenuSceneBuildIndex < 0 || mainMenuSceneBuildIndex >= SceneManager.sceneCountInBuildSettings)
            {
                if (debugLogs) Debug.Log($"[EndingUI] Invalid mainMenuSceneBuildIndex={mainMenuSceneBuildIndex}");
                return;
            }

            if (preloadOperation != null)
            {
                preloadOperation.allowSceneActivation = true;
                return;
            }

            SceneManager.LoadSceneAsync(mainMenuSceneBuildIndex);
        }

        public void GenerateSummaryWithAI()
        {
            if (summarayText != null && !string.IsNullOrWhiteSpace(requestingText))
            {
                summarayText.text = requestingText;
            }

            if (summaryCoroutine != null)
            {
                StopCoroutine(summaryCoroutine);
                summaryCoroutine = null;
            }

            summaryCoroutine = StartCoroutine(GenerateSummaryRoutine());
        }

        private IEnumerator GenerateSummaryRoutine()
        {
            if (chatManager == null)
            {
                chatManager = FindObjectOfType<LLMChatManager>();
            }

            ILLMService service = GetActiveService();
            if (service == null)
            {
                ApplySummaryText("AI 服务未连接。");
                yield break;
            }

            string knownFacts = includeKnownFactsFromContextMemory ? BuildKnownFactsText(chatManager.contextMemory) : "无";
            string historyText = BuildHistoryText(chatManager.fullChatLog, maxHistoryMessages);
            string userPrompt = summaryUserPromptTemplate.Replace("{KNOWN_FACTS}", knownFacts).Replace("{CHAT_HISTORY}", historyText);

            List<Message> messages = new List<Message>
            {
                new Message { role = "system", content = summarySystemPrompt },
                new Message { role = "user", content = userPrompt }
            };

            string result = null;
            bool ok = false;

            yield return service.SendStatelessMessage(messages, (reply, success) =>
            {
                result = reply;
                ok = success;
            });

            if (!ok)
            {
                ApplySummaryText(string.IsNullOrWhiteSpace(result) ? "AI 总结失败。" : result);
                yield break;
            }

            string summary = TryParseSummaryJson(result);
            ApplySummaryText(string.IsNullOrWhiteSpace(summary) ? result : summary);
        }

        public void ApplyDebugSummary()
        {
            ApplySummaryText(debugSummaryString);
        }

        public void SetOutcome(EndingOutcome newOutcome)
        {
            outcome = newOutcome;
            ApplyOutcomeInformationText();
        }

        public void SetOutcomeEscaped()
        {
            SetOutcome(EndingOutcome.Escaped);
        }

        public void SetOutcomeFainted()
        {
            SetOutcome(EndingOutcome.Fainted);
        }

        public void ApplyOutcomeInformationText()
        {
            switch (outcome)
            {
                case EndingOutcome.Escaped:
                    ApplyInformationText(escapedInformationString);
                    break;
                case EndingOutcome.Fainted:
                    ApplyInformationText(faintedInformationString);
                    break;
            }
        }

        private void ApplySummaryText(string value)
        {
            if (summarayText == null) { return; }
            summarayText.text = value ?? string.Empty;
        }

        private void ApplyInformationText(string value)
        {
            if (informationText == null) { return; }
            informationText.text = value ?? string.Empty;
        }

        private ILLMService GetActiveService()
        {
            if (chatManager == null) { return null; }

            switch (chatManager.currentProvider)
            {
                case LLMChatManager.LLMProvider.DeepSeek:
                    return chatManager.deepSeekService;
                case LLMChatManager.LLMProvider.Doubao:
                    return chatManager.doubaoService;
                default:
                    return null;
            }
        }

        private string BuildKnownFactsText(ContextMemoryManager memory)
        {
            if (memory == null || memory.facts == null || memory.facts.Count == 0) { return "无"; }

            System.Text.StringBuilder sb = new System.Text.StringBuilder();
            int count = Mathf.Min(30, memory.facts.Count);
            for (int i = 0; i < count; i++)
            {
                var fact = memory.facts[i];
                sb.Append(i + 1).Append(". [").Append(fact.key).Append("]: ").Append(fact.value).Append('\n');
            }

            return sb.ToString();
        }

        private string BuildHistoryText(List<Message> fullLog, int maxCount)
        {
            if (fullLog == null || fullLog.Count == 0) { return "无"; }

            int take = Mathf.Max(1, maxCount);
            int start = Mathf.Max(0, fullLog.Count - take);

            System.Text.StringBuilder sb = new System.Text.StringBuilder();
            for (int i = start; i < fullLog.Count; i++)
            {
                var msg = fullLog[i];
                if (msg == null) { continue; }
                if (msg.role != "user" && msg.role != "assistant") { continue; }
                sb.Append(msg.role).Append(": ").Append(msg.content).Append('\n');
            }

            return sb.ToString();
        }

        private string TryParseSummaryJson(string raw)
        {
            if (string.IsNullOrWhiteSpace(raw)) { return null; }

            string json = raw.Trim();
            json = json.Replace("```json", "").Replace("```", "").Trim();

            SummaryResponse parsed = null;
            try
            {
                parsed = JsonUtility.FromJson<SummaryResponse>(json);
            }
            catch
            {
                parsed = null;
            }

            if (parsed == null || string.IsNullOrWhiteSpace(parsed.summary)) { return null; }
            return parsed.summary.Trim();
        }

        private TMP_Text FindTMPByNameHint(string hint1, string hint2)
        {
            TMP_Text[] all = GetComponentsInChildren<TMP_Text>(true);
            if (all == null || all.Length == 0) { return null; }

            for (int i = 0; i < all.Length; i++)
            {
                var t = all[i];
                if (t == null) { continue; }
                string n = t.gameObject.name;
                if (!string.IsNullOrEmpty(n) && (n.IndexOf(hint1, StringComparison.OrdinalIgnoreCase) >= 0 || n.IndexOf(hint2, StringComparison.OrdinalIgnoreCase) >= 0))
                {
                    return t;
                }
            }

            return all[0];
        }

        private void WireOnce()
        {
            if (isWired) { return; }

            if (returnToMenuButton != null) { returnToMenuButton.onClick.AddListener(ReturnToMainMenu); }
            if (returnToMenuButtonUGUI != null) { returnToMenuButtonUGUI.onClick.AddListener(ReturnToMainMenu); }

            if (debugSummaryButton != null) { debugSummaryButton.onClick.AddListener(ApplyDebugSummary); }
            if (debugSummaryButtonUGUI != null) { debugSummaryButtonUGUI.onClick.AddListener(ApplyDebugSummary); }

            isWired = true;
        }
    }
}