using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using UnityEditor;
using UnityEngine;
using BaseGames.Localization;

namespace BaseGames.Editor.Localization
{
    /// <summary>
    /// 本地化 CSV 导入/导出工具。
    ///
    /// 每个表导出为独立 CSV，列顺序：key, ChineseSimplified, English, Japanese, Korean。
    /// 文件存放路径：Assets/_Game/Localization/Export/{TableName}.csv
    ///
    /// 导入：读取 CSV → 回写 Resources/Localization/{Language}/{TableName}.json
    ///
    /// 菜单：BaseGames / Localization / CSV 导入导出工具
    /// </summary>
    public class LocalizationCsvTool : EditorWindow
    {
        [MenuItem("BaseGames/Localization/CSV 导入导出工具")]
        private static void Open()
        {
            var win = GetWindow<LocalizationCsvTool>("本地化 CSV 工具");
            win.minSize = new Vector2(480, 360);
        }

        // ── 状态 ─────────────────────────────────────────────────────────────

        private static readonly Language[] s_allLanguages =
            (Language[])Enum.GetValues(typeof(Language));

        private static readonly string[] s_allTables =
        {
            LocalizationTable.UI,
            LocalizationTable.Dialogue,
            LocalizationTable.Quest,
            LocalizationTable.Spells,
            LocalizationTable.Skills,
            LocalizationTable.Items,
            LocalizationTable.Character,
            LocalizationTable.Tutorial,
        };

        private const string ExportDir = "Assets/_Game/Localization/Export";

        private readonly bool[] _exportSelected = new bool[s_allTables.Length];
        private readonly bool[] _importSelected = new bool[s_allTables.Length];
        private string           _statusMessage  = "";
        private MessageType      _statusType     = MessageType.None;
        private Vector2          _scroll;

        // ── GUI ───────────────────────────────────────────────────────────────

        private void OnGUI()
        {
            _scroll = EditorGUILayout.BeginScrollView(_scroll);

            EditorGUILayout.Space(6);
            GUILayout.Label("📤  导出 → CSV", EditorStyles.boldLabel);
            EditorGUILayout.HelpBox(
                $"将 Resources/Localization/ 中的 JSON 表导出为 CSV 文件。\n" +
                $"目标目录：{ExportDir}/",
                MessageType.Info);

            EditorGUI.indentLevel++;
            for (int i = 0; i < s_allTables.Length; i++)
                _exportSelected[i] = EditorGUILayout.Toggle(s_allTables[i], _exportSelected[i]);
            EditorGUI.indentLevel--;

            EditorGUILayout.BeginHorizontal();
            if (GUILayout.Button("全选")) SetAll(_exportSelected, true);
            if (GUILayout.Button("全不选")) SetAll(_exportSelected, false);
            EditorGUILayout.EndHorizontal();

            EditorGUILayout.Space(4);
            if (GUILayout.Button("▶ 导出选中表", GUILayout.Height(30)))
                RunExport();

            EditorGUILayout.Space(16);
            EditorGUILayout.LabelField("", GUI.skin.horizontalSlider);

            GUILayout.Label("📥  导入 ← CSV", EditorStyles.boldLabel);
            EditorGUILayout.HelpBox(
                $"读取 {ExportDir}/ 中的 CSV，回写至 Resources/Localization/ JSON 文件。\n" +
                "已有 Key 覆盖，新增 Key 追加，不删除多余 Key。",
                MessageType.Info);

            EditorGUI.indentLevel++;
            for (int i = 0; i < s_allTables.Length; i++)
                _importSelected[i] = EditorGUILayout.Toggle(s_allTables[i], _importSelected[i]);
            EditorGUI.indentLevel--;

            EditorGUILayout.BeginHorizontal();
            if (GUILayout.Button("全选")) SetAll(_importSelected, true);
            if (GUILayout.Button("全不选")) SetAll(_importSelected, false);
            EditorGUILayout.EndHorizontal();

            EditorGUILayout.Space(4);
            if (GUILayout.Button("▶ 导入选中表", GUILayout.Height(30)))
                RunImport();

            EditorGUILayout.Space(8);
            if (!string.IsNullOrEmpty(_statusMessage))
                EditorGUILayout.HelpBox(_statusMessage, _statusType);

            EditorGUILayout.Space(6);
            EditorGUILayout.EndScrollView();
        }

        // ── 导出 ─────────────────────────────────────────────────────────────

        private void RunExport()
        {
            EnsureDirectory(ExportDir);
            int exported = 0;

            try
            {
                for (int ti = 0; ti < s_allTables.Length; ti++)
                {
                    if (!_exportSelected[ti]) continue;
                    string tableName = s_allTables[ti];

                    EditorUtility.DisplayProgressBar("导出 CSV", $"导出 {tableName}…", (float)ti / s_allTables.Length);

                    // 收集所有语言的字典（以第一个语言的 Key 集合为主键集）
                    var langDicts = new Dictionary<Language, Dictionary<string, string>>();
                    var allKeys   = new SortedSet<string>(StringComparer.Ordinal);

                    foreach (var lang in s_allLanguages)
                    {
                        LocalizationManager.ClearEditorPreviewCache();
                        var dict = LocalizationManager.GetEditorTable(lang, tableName);
                        if (dict != null)
                        {
                            langDicts[lang] = dict;
                            foreach (var k in dict.Keys) allKeys.Add(k);
                        }
                    }

                    if (allKeys.Count == 0)
                    {
                        Debug.LogWarning($"[CsvTool] 表「{tableName}」无数据，跳过导出。");
                        continue;
                    }

                    var sb = new StringBuilder();
                    // 表头
                    sb.Append("key");
                    foreach (var lang in s_allLanguages)
                        sb.Append(',').Append(lang);
                    sb.AppendLine();

                    // 数据行
                    foreach (var key in allKeys)
                    {
                        sb.Append(CsvEscape(key));
                        foreach (var lang in s_allLanguages)
                        {
                            string val = "";
                            if (langDicts.TryGetValue(lang, out var d))
                                d.TryGetValue(key, out val);
                            sb.Append(',').Append(CsvEscape(val ?? ""));
                        }
                        sb.AppendLine();
                    }

                    string csvPath = $"{ExportDir}/{tableName}.csv";
                    File.WriteAllText(csvPath, sb.ToString(), Encoding.UTF8);
                    exported++;
                }
            }
            finally
            {
                EditorUtility.ClearProgressBar();
            }

            AssetDatabase.Refresh();
            SetStatus($"✅ 成功导出 {exported} 个表到 {ExportDir}/", MessageType.Info);
        }

        // ── 导入 ─────────────────────────────────────────────────────────────

        private void RunImport()
        {
            int imported = 0;
            int errors   = 0;

            try
            {
                for (int ti = 0; ti < s_allTables.Length; ti++)
                {
                    if (!_importSelected[ti]) continue;
                    string tableName = s_allTables[ti];
                    string csvPath   = Path.Combine(Path.GetDirectoryName(Application.dataPath)!, $"{ExportDir}/{tableName}.csv");

                    EditorUtility.DisplayProgressBar("导入 CSV", $"导入 {tableName}…", (float)ti / s_allTables.Length);

                    if (!File.Exists(csvPath))
                    {
                        Debug.LogWarning($"[CsvTool] CSV 文件不存在，跳过：{ExportDir}/{tableName}.csv");
                        continue;
                    }

                    try
                    {
                        var rows    = ParseCsv(File.ReadAllText(csvPath, Encoding.UTF8));
                        if (rows.Count < 2) continue;

                        // 表头行解析出列对应的语言
                        var header = rows[0];
                        var langCols = new List<(int col, Language lang)>();
                        for (int col = 1; col < header.Count; col++)
                        {
                            if (Enum.TryParse<Language>(header[col].Trim(), out var lang))
                                langCols.Add((col, lang));
                        }

                        // 为每个语言准备合并后的字典
                        var mergedDicts = new Dictionary<Language, Dictionary<string, string>>();
                        foreach (var (_, lang) in langCols)
                        {
                            LocalizationManager.ClearEditorPreviewCache();
                            var existing = LocalizationManager.GetEditorTable(lang, tableName)
                                           ?? new Dictionary<string, string>(StringComparer.Ordinal);
                            mergedDicts[lang] = new Dictionary<string, string>(existing, StringComparer.Ordinal);
                        }

                        // 用 CSV 数据覆盖/追加
                        for (int row = 1; row < rows.Count; row++)
                        {
                            var cells = rows[row];
                            if (cells.Count == 0 || string.IsNullOrWhiteSpace(cells[0])) continue;
                            string key = cells[0];
                            foreach (var (col, lang) in langCols)
                            {
                                string val = col < cells.Count ? cells[col] : "";
                                mergedDicts[lang][key] = val;
                            }
                        }

                        // 写回 JSON
                        foreach (var (lang, dict) in mergedDicts)
                        {
                            string jsonPath = GetJsonPath(lang, tableName);
                            EnsureDirectory(Path.GetDirectoryName(jsonPath));
                            File.WriteAllText(jsonPath, DictToJson(dict), Encoding.UTF8);
                        }

                        imported++;
                    }
                    catch (Exception ex)
                    {
                        Debug.LogError($"[CsvTool] 导入「{tableName}」失败：{ex.Message}");
                        errors++;
                    }
                }
            }
            finally
            {
                EditorUtility.ClearProgressBar();
            }

            AssetDatabase.Refresh();
            LocalizationManager.ClearEditorPreviewCache();

            string msg = errors == 0
                ? $"✅ 成功导入 {imported} 个表。"
                : $"⚠ 导入 {imported} 个表，{errors} 个失败（见控制台）。";
            SetStatus(msg, errors == 0 ? MessageType.Info : MessageType.Warning);
        }

        // ── 工具函数 ─────────────────────────────────────────────────────────

        /// <summary>将 value 按 RFC 4180 规范包裹（含逗号/双引号/换行时用双引号包裹，内部双引号转义为 ""）。</summary>
        private static string CsvEscape(string value)
        {
            if (value == null) return "";
            bool needsQuote = value.Contains(',') || value.Contains('"') || value.Contains('\n') || value.Contains('\r');
            if (!needsQuote) return value;
            return "\"" + value.Replace("\"", "\"\"") + "\"";
        }

        /// <summary>简单 CSV 解析器，支持 RFC 4180 带引号字段（含换行）。</summary>
        private static List<List<string>> ParseCsv(string text)
        {
            var rows = new List<List<string>>();
            var row  = new List<string>();
            var cell = new StringBuilder();
            bool inQuote = false;
            int  i = 0;

            while (i < text.Length)
            {
                char c = text[i];
                if (inQuote)
                {
                    if (c == '"')
                    {
                        if (i + 1 < text.Length && text[i + 1] == '"')
                        { cell.Append('"'); i += 2; }
                        else
                        { inQuote = false; i++; }
                    }
                    else
                    { cell.Append(c); i++; }
                }
                else
                {
                    if (c == '"')
                    { inQuote = true; i++; }
                    else if (c == ',')
                    { row.Add(cell.ToString()); cell.Clear(); i++; }
                    else if (c == '\r')
                    {
                        row.Add(cell.ToString()); cell.Clear();
                        rows.Add(row); row = new List<string>();
                        if (i + 1 < text.Length && text[i + 1] == '\n') i++;
                        i++;
                    }
                    else if (c == '\n')
                    { row.Add(cell.ToString()); cell.Clear(); rows.Add(row); row = new List<string>(); i++; }
                    else
                    { cell.Append(c); i++; }
                }
            }

            if (cell.Length > 0 || row.Count > 0)
            {
                row.Add(cell.ToString());
                rows.Add(row);
            }

            return rows;
        }

        /// <summary>将字符串字典序列化为最小 JSON 对象（UTF-8，适合直接写入 Resources JSON）。</summary>
        private static string DictToJson(Dictionary<string, string> dict)
        {
            var sb = new StringBuilder();
            sb.AppendLine("{");
            int written = 0;
            foreach (var kv in dict)
            {
                sb.Append("  ").Append(JsonString(kv.Key)).Append(": ").Append(JsonString(kv.Value));
                if (++written < dict.Count) sb.Append(',');
                sb.AppendLine();
            }
            sb.Append('}');
            return sb.ToString();
        }

        private static string JsonString(string s)
        {
            if (s == null) return "\"\"";
            s = s.Replace("\\", "\\\\")
                 .Replace("\"", "\\\"")
                 .Replace("\n", "\\n")
                 .Replace("\r", "\\r")
                 .Replace("\t", "\\t");
            return $"\"{s}\"";
        }

        private static string GetJsonPath(Language lang, string tableName)
            => $"Assets/Resources/Localization/{lang}/{tableName}.json";

        private static void EnsureDirectory(string dir)
        {
            if (!string.IsNullOrEmpty(dir) && !Directory.Exists(dir))
                Directory.CreateDirectory(dir);
        }

        private static void SetAll(bool[] arr, bool v)
        {
            for (int i = 0; i < arr.Length; i++) arr[i] = v;
        }

        private void SetStatus(string msg, MessageType type)
        {
            _statusMessage = msg;
            _statusType    = type;
            Repaint();
        }
    }
}