using Aliyun.OSS;
using DaJiaoYan.Models;
using DaJiaoYan.Utils;
using System;
using System.IO;
using System.Text.RegularExpressions;

namespace DaJiaoYan.Services
{
    public static class AliyunOss
    {
        private static AliyunOssClient client = null;
        /// <summary>
        /// 客户端锁
        /// </summary>
        private readonly static object ClientLock = new object();

        private static AliyunOssClient Client
        {
            get
            {
                if (client == null)
                {
                    lock (ClientLock)
                    {
                        client = new AliyunOssClient();
                    }
                }

                return client;
            }
        }

        /// <summary>
        /// 上传
        /// </summary>
        /// <param name="bucketName"></param>
        /// <param name="objectName"></param>
        /// <param name="requestContent"></param>
        /// <returns></returns>
        public static bool SimpleUpload(string objectName, MemoryStream requestContent)
        {
            return Client.SimpleUpload(objectName, requestContent);
        }

        /// <summary>
        /// 上传
        /// </summary>
        /// <param name="bucketName"></param>
        /// <param name="objectName"></param>
        /// <param name="localFilename"></param>
        /// <returns></returns>
        public static bool SimpleUpload(string objectName, string localFilename)
        {
            return Client.SimpleUpload(objectName, localFilename);
        }
    }

    public class AliyunOssClient
    {
        public delegate void DeleWriteLog(string txt);
        public static DeleWriteLog WriteLog;

        private static OssClient client = null;
        private static AliyunAccessModel accessModel = null;
        /// <summary>
        /// 客户端锁
        /// </summary>
        private readonly static object ClientLock = new object();

        /// <summary>
        /// 授权有效期临界值
        /// </summary>
        private const int EXP_THRESHOLD = 60 * 2 * 1000;
        private readonly string token = null;

        public AliyunOssClient(string token = null)
        {
            this.token = token;
        }

        private AliyunAccessModel Access
        {
            get
            {
                lock (ClientLock)
                {
                    if (accessModel == null || accessModel.Expiration - EXP_THRESHOLD < Functions.GetTimeStamp())
                    {
                        //lock (accessModel)
                        //{
                        accessModel = Api.GetAliyunAccess(token).Result;
                        if (accessModel != null)
                        {
                            accessModel.Expiration = Functions.GetTimeStamp() + accessModel.Expiration * 1000;
                            accessModel.EndPoint = Regex.Replace(accessModel.EndPoint, @"-internal", "", RegexOptions.IgnoreCase);
                        }

                        //}
                    }
                }

                return accessModel;
            }
        }

        public bool AccessAvailable
        {
            get
            {
                return !string.IsNullOrEmpty(Access?.EndPoint) && !string.IsNullOrEmpty(Access?.AccessKeyId) && !string.IsNullOrEmpty(Access?.AccessKeySecret);
            }
        }


        private OssClient Client
        {
            get
            {
                if (client == null && AccessAvailable)
                {
                    client = new OssClient(Access?.EndPoint, Access?.AccessKeyId, Access?.AccessKeySecret);
                }
                return client;
            }
        }

        /// <summary>
        /// 上传
        /// </summary>
        /// <param name="bucketName"></param>
        /// <param name="objectName"></param>
        /// <param name="requestContent"></param>
        /// <returns></returns>
        public bool SimpleUpload(string objectName, Stream requestContent)
        {
            //// yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1（杭州）为例，Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。
            //var endpoint = "yourEndpoint";
            //// 阿里云账号AccessKey拥有所有API的访问权限，风险很高。强烈建议您创建并使用RAM用户进行API访问或日常运维，请登录RAM控制台创建RAM用户。
            //var accessKeyId = "yourAccessKeyId";
            //var accessKeySecret = "yourAccessKeySecret";
            //// 填写Bucket名称。
            //var bucketName = "examplebucket";
            //// 填写Object完整路径。Object完整路径中不能包含Bucket名称。
            //var objectName = "exampleobject.txt";
            //// 填写字符串。
            //var objectContent = "More than just cloud.";

            // 创建OssClient实例。
            //var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
            bool res = false;
            try
            {
                //byte[] binaryData = Encoding.ASCII.GetBytes(objectContent);
                //MemoryStream requestContent = new MemoryStream(binaryData);
                // 上传文件。
                Client?.PutObject(Access?.BucketName, objectName, requestContent);
                res = true;
            }
            catch (Exception ex)
            {
                WriteLog?.Invoke($"Put object failed, {ex.Message}");
                WriteLog?.Invoke(ex.StackTrace);
            }
            return res;
        }

        /// <summary>
        /// 上传
        /// </summary>
        /// <param name="bucketName"></param>
        /// <param name="objectName"></param>
        /// <param name="localFilename"></param>
        /// <returns></returns>
        public bool SimpleUpload(string objectName, string localFilename)
        {
            bool res = false;
            //PutObjectResult r;
            try
            {
                //byte[] binaryData = Encoding.ASCII.GetBytes(objectContent);
                //MemoryStream requestContent = new MemoryStream(binaryData);
                for (int i = 0; i < 5; i++)
                {
                    using (PutObjectResult r = Client?.PutObject(Access?.BucketName, objectName, localFilename))
                    {
                        //r = t.
                        if (r?.HttpStatusCode == System.Net.HttpStatusCode.OK)
                        {
                            res = true;
                            break;
                        }
                    }
                }
                // 上传文件。
            }
            catch (Exception ex)
            {
                WriteLog?.Invoke($"Put object failed, {ex.Message}");
                WriteLog?.Invoke(ex.StackTrace);
            }
            return res;
        }

    }
}