using LMS.Common.Extensions;
using LMS.DAO.OptionDAO;
using LMS.Repository.DB;
using LMS.Repository.FileUpload;
using Microsoft.Extensions.Logging;
using Qiniu.Http;
using Qiniu.IO;
using Qiniu.IO.Model;
using Qiniu.Util;
using System.Security.Cryptography;
using static LMS.Repository.DTO.FileUploadDto;

namespace LMS.Tools.FileTool
{
    public class QiniuService(OptionGlobalDAO optionGlobalDAO, ILogger<QiniuService> logger) : IQiniuService
    {
        private readonly OptionGlobalDAO _optionGlobalDAO = optionGlobalDAO;
        private readonly UploadManager _uploadManager = new UploadManager();
        private readonly ILogger<QiniuService> _logger = logger;

        /// <summary>
        /// 检查文件的字节大小是否符合要求
        /// </summary>
        /// <param name="fileBytes"></param>
        /// <returns></returns>
        public async Task<UploadResult> CheckFileBytesSize(byte[] fileBytes)
        {
            if (fileBytes == null || fileBytes.Length == 0)
            {
                return new UploadResult
                {
                    Success = false,
                    Message = "文件字节数据不能为空"
                };
            }

            double MaxFileSize = await _optionGlobalDAO.FindAndReturnOption<double>("SYS_MaxUploadFileSize");

            if (fileBytes.Length > MaxFileSize * 1024 * 1024)
            {
                return new UploadResult
                {
                    Success = false,
                    Message = $"文件大小不能超过 {MaxFileSize}MB"
                };
            }

            return new UploadResult { Success = true, Message = string.Empty };
        }

        public string ComputeSHA1Hash(byte[] data)
        {
            var hash = SHA1.HashData(data);
            return Convert.ToHexString(hash).ToLower();
        }

        public string GenerateFileKey(long userId, string fileName)
        {
            var date = DateTime.Now.ToString("yyyyMMdd");
            //var extension = Path.GetExtension(fileName);
            return $"user/{userId}/{date}/{fileName}";
        }

        public async Task<QiniuSettings> InitQiniuSetting()
        {
            QiniuSettings? qiniuSettings = await _optionGlobalDAO.FindAndReturnOption<QiniuSettings>("SYS_QiniuSetting");

            if (qiniuSettings == null || string.IsNullOrEmpty(qiniuSettings.AccessKey) || string.IsNullOrEmpty(qiniuSettings.SecretKey) || string.IsNullOrEmpty(qiniuSettings.BucketName) || string.IsNullOrEmpty(qiniuSettings.Domain))
            {
                throw new Exception("七牛云配置不完整，请检查配置，请联系管理员");
            }
            return qiniuSettings;
        }

        public string GeneratePolicy(QiniuSettings qiniuSettings)
        {
            Mac mac = new(qiniuSettings.AccessKey, qiniuSettings.SecretKey);
            var putPolicy = new PutPolicy
            {
                Scope = qiniuSettings.BucketName
            };
            if (qiniuSettings.DeleteDay != null)
            {
                putPolicy.DeleteAfterDays = qiniuSettings.DeleteDay.Value; // 设置过期时间
            }
            putPolicy.SetExpires(3600);
            string token = Auth.CreateUploadToken(mac, putPolicy.ToJsonString());
            return token;
        }

        public string BuildFileUrl(string domain, string fileKey)
        {
            return $"{domain}/{fileKey}";
        }

        public async Task<FileUploads> UploadFileToQiNiu(byte[] fileBytes, long userId, string fileName, string fileKey)
        {
            QiniuSettings qiniuSettings = await InitQiniuSetting();
            string token = GeneratePolicy(qiniuSettings);
            string hash = ComputeSHA1Hash(fileBytes);
            HttpResult uploadResult;

            _logger.LogInformation("开始上传文件, 用户ID: {userId}, 文件名: {fileName}, 文件大小: {fileLength} 字节, 文件Key: {fileKey}", userId, fileName, fileBytes.Length, fileKey);

            using (var stream = new MemoryStream(fileBytes))
            {
                uploadResult = await _uploadManager.UploadStreamAsync(stream, fileKey, token);
            }
            // 8. 检查上传结果
            if (uploadResult.Code != 200)
            {
                _logger.LogError("文件上传失败, 上传用户ID: {userId}, 错误信息: {error}", userId, uploadResult.Text);
                throw new Exception(uploadResult.Text);
            }

            var qiniuUrl = BuildFileUrl(qiniuSettings.Domain, fileKey);

            _logger.LogInformation("文件上传成功, 上传用户ID: {userId}, 文件Key: {fileKey}，文件链接: {url}", userId, fileKey, qiniuUrl);
            return new FileUploads
            {
                UserId = userId,
                FileName = fileName,
                FileKey = fileKey,
                FileSize = fileBytes.Length,
                ContentType = "application/octet-stream",
                Hash = hash,
                QiniuUrl = qiniuUrl,
                UploadTime = DateTime.Now,
                Status = "active",
                CreatedAt = DateTime.Now,
                DeleteTime = qiniuSettings.DeleteDay != null ? BeijingTimeExtension.GetBeijingTime().AddDays((double)qiniuSettings.DeleteDay) : DateTime.MaxValue // 默认未删除
            };
        }
    }
}