using System.IO;
using System.Collections.Generic;
using UnityEditor;
using UnityEngine;
using Newtonsoft.Json.Linq;

namespace SLSUtilities.Narrative.Editor
{
    /// <summary>
    /// Yarn Spinner 自动 YSLS 合并器。
    /// 自动将来自不同程序集（Assembly-CSharp、SLSUtilities等）生成的多个 YSLS 声明文件
    /// 合并成一个单一的 combined.ysls.json 文件，输出到项目根目录下，
    /// 从而完美解决 VS Code 中 Yarn Spinner 插件只能同时加载一个 definitions 文件的限制！
    /// </summary>
    [InitializeOnLoad]
    public static class YslsMerger
    {
        static YslsMerger()
        {
            // 每次 Unity 重新编译、资源导入或启动时自动运行
            EditorApplication.delayCall += MergeYslsFiles;
        }

        [MenuItem("Tools/Yarn Spinner/Merge YSLS Files")]
        public static void MergeYslsFiles()
        {
            string packagePath = Path.Combine(Directory.GetCurrentDirectory(), "ProjectSettings", "Packages", "dev.yarnspinner");
            if (!Directory.Exists(packagePath))
            {
                return;
            }

            string combinedFileName = "combined.ysls.json";
            string outputRootPath = Path.Combine(packagePath, combinedFileName);

            try
            {
                // 搜索所有以 -generated.ysls.json 结尾的声明文件
                string[] files = Directory.GetFiles(packagePath, "*-generated.ysls.json");
                if (files.Length == 0)
                {
                    return;
                }

                JArray allCommands = new JArray();
                JArray allFunctions = new JArray();
                int version = 2;

                foreach (string file in files)
                {
                    if (Path.GetFileName(file) == combinedFileName) continue;

                    string json = File.ReadAllText(file);
                    if (string.IsNullOrEmpty(json)) continue;

                    JObject root = JObject.Parse(json);
                    
                    if (root.TryGetValue("version", out JToken vToken))
                    {
                        version = Mathf.Max(version, vToken.Value<int>());
                    }

                    if (root.TryGetValue("commands", out JToken cToken) && cToken is JArray commandsArray)
                    {
                        foreach (var cmd in commandsArray)
                        {
                            allCommands.Add(cmd);
                        }
                    }

                    if (root.TryGetValue("functions", out JToken fToken) && fToken is JArray functionsArray)
                    {
                        foreach (var func in functionsArray)
                        {
                            allFunctions.Add(func);
                        }
                    }
                }

                // 组装合并后的 JObject
                JObject combined = new JObject
                {
                    ["version"] = version,
                    ["commands"] = allCommands,
                    ["functions"] = allFunctions
                };

                // 写入项目根目录
                File.WriteAllText(outputRootPath, combined.ToString(Newtonsoft.Json.Formatting.Indented));
                Debug.Log($"[YSLS Merger] 成功将 {files.Length} 个 YSLS 声明文件合并至: '{outputRootPath}'。现在您可以在 VS Code 中一键加载此合并文件！");
            }
            catch (System.Exception ex)
            {
                // 自动合并失败通常发生在初始无缓存时，作警告处理，不中断编辑体验
                Debug.LogWarning($"[YSLS Merger] 自动合并 YSLS 文件失败（这通常是由于 Yarn Spinner 尚未生成初始的 ysls 缓存文件导致的，属于正常现象）：{ex.Message}");
            }
        }
    }
}