using Cysharp.Threading.Tasks;
using System;
using System.Collections;
using System.Collections.Generic;
using System.IO.Compression;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Threading;
using UnityEngine;
using UnityEngine.Networking;

public class FileUpLoad
{

    //随机Key，方便查询上传的文件
    private static readonly char[] charSet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789".ToCharArray();
    public static string GetRandomNum()
    {
        byte[] randomBytes = new byte[8];
        using (var rng = RandomNumberGenerator.Create())
        {
            rng.GetBytes(randomBytes);
        }

        StringBuilder sb = new StringBuilder(8);
        foreach (byte b in randomBytes)
        {
            // 62进制映射（62=26大写+26小写+10数字）
            sb.Append(charSet[b % 62]);
        }
        return sb.ToString();
    }


    #region 配置参数
    public static string UploadEndpoint { get; set; } = $"你的日志存放地址";

    /// <summary> 超时抛出 </summary>
    public static int TimeoutSeconds { get; set; } = 20;

    /// <summary> 压缩枚举 </summary>
    public static System.IO.Compression.CompressionLevel TextCompressionLevel { get; set; } = System.IO.Compression.CompressionLevel.Optimal;

    /*
     * ‌NoCompression‌	不执行压缩操作，直接存储原始数据	需要快速写入但无需压缩的场景‌
‌       Fastest‌	        快速压缩，牺牲压缩率以提升速度	对实时性要求高的场景（如日志记录）‌
‌       Optimal‌	        平衡压缩率与速度（默认选项）	通用文件压缩需求（如用户数据存档）‌
‌       SmallestSize‌	    最大压缩率，牺牲速度以减小文件体积	网络传输或存储空间敏感场景‌
     */

    #endregion

    #region 核心上传API
    /// <summary>
    /// 智能文件上传（支持文本压缩）
    /// </summary>
    /// <param name="filePath">完整文件路径</param>
    /// <param name="ct">取消令牌</param>
    /// <returns>元组（是否成功，响应数据/错误信息）</returns>
    public static async UniTask<(bool success, string result)> UploadFileAsync(
        string filePath,
        CancellationToken ct = default)
    {
        try
        {
            // 强制主线程执行上下文
            await UniTask.SwitchToMainThread();

            // 文件基础校验
            if (!System.IO.File.Exists(filePath))
                return (false, $"文件不存在: {Path.GetFileName(filePath)}");

            // 动态处理文件
            var (payload, fileName, mime) = await ProcessFile(filePath, ct);

            // 构建网络请求
            using var request = CreateUploadRequest(payload, fileName, mime);
            var (isSuccess, result) = await ExecuteRequest(request, ct);

            return (isSuccess, isSuccess
                ? $"上传成功: {result}"
                : $"服务器拒绝: {result}");
        }
        catch (Exception ex) when (ex is not OperationCanceledException)
        {
            return (false, FormatException(ex));
        }
    }
    #endregion

    #region 私有方法
    private static async UniTask<(byte[] data, string name, string mime)> ProcessFile(
        string path,
        CancellationToken ct)
    {
        // 自动识别文本类型
        if (IsTextFile(path))
        {
            var compressed = await CompressTextAsync(path, ct);
            return (compressed.data, compressed.name, "application/zip");
        }

        // 非文本文件直传
        var bytes = await System.IO.File.ReadAllBytesAsync(path, ct);
        return (bytes, Path.GetFileName(path), GetMimeType(Path.GetExtension(path)));
    }

    private static UnityWebRequest CreateUploadRequest(byte[] data, string name, string mime)
    {
        var form = new WWWForm();

        //附加参数
        //string tRoId = string.Empty;
        //form.AddField("roleid", tRoId);
        //string tServerId = TcpManager.CurServerData != null ? TcpManager.CurServerData.server_id : "0";
        //form.AddField("serverId", tServerId);
        //form.AddField("packageNo", AppEntry.PkgConfig.PackageID);
        //form.AddField("platform", Common.GetPlatformPath());
        //form.AddField("content", mIptContent);
        //form.AddField("type", 2);
        //form.AddField("fdtype", mSelectName);

        form.AddBinaryData("file", data, name, mime);
        var request = UnityWebRequest.Post(UploadEndpoint, form);
        request.timeout = TimeoutSeconds;
        return request;
    }

    private static async UniTask<(bool isSuccess, string result)> ExecuteRequest(
        UnityWebRequest request,
        CancellationToken ct)
    {
        try
        {
            var operation = request.SendWebRequest();
            while (!operation.isDone && !ct.IsCancellationRequested)
            {
                await UniTask.Yield(PlayerLoopTiming.Update, ct);
            }

            if (ct.IsCancellationRequested)
            {
                request.Abort();
                return (false, "用户取消操作");
            }

            return request.result == UnityWebRequest.Result.Success
                ? (true, request.downloadHandler.text)
                : (false, $"[{request.responseCode}] {request.error}");
        }
        finally
        {
            request.Dispose();
        }
    }
    #endregion

    #region 工具方法
    private static async UniTask<(byte[] data, string name)> CompressTextAsync(
        string path,
        CancellationToken ct)
    {
        await using var memStream = new MemoryStream();
        using (var archive = new ZipArchive(memStream, ZipArchiveMode.Create, true))
        {
            var entry = archive.CreateEntry(Path.GetFileName(path), TextCompressionLevel);
            await using (var entryStream = entry.Open())
            await using (var fileStream = System.IO.File.OpenRead(path))
            {
                await fileStream.CopyToAsync(entryStream, 81920, ct);
            }
        }
        return (memStream.ToArray(), $"{Path.GetFileNameWithoutExtension(path)}.zip");
    }

    private static bool IsTextFile(string path)
    {
        var ext = Path.GetExtension(path).ToLower();
        return ext is ".txt" or ".log" or ".csv" or ".json";
    }

    private static string GetMimeType(string ext) => ext switch
    {
        ".zip" => "application/zip",
        ".txt" => "text/plain",
        ".jpg" => "image/jpeg",
        _ => "application/octet-stream"
    };

    private static string FormatException(Exception ex) => ex switch
    {
        UnityWebRequestException uwrEx => $"网络错误 [{uwrEx.ResponseCode}]: {uwrEx.Message}",
        IOException ioEx => $"文件系统错误: {ioEx.Message}",
        UnauthorizedAccessException uaEx => $"权限不足: {uaEx.Message}",
        _ => $"系统异常: {ex.GetBaseException().Message}"
    };
    #endregion
}