/*----------------------------------------------------------------------------------

// Copyright 2019 Huawei Technologies Co.,Ltd.

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use

// this file except in compliance with the License.  You may obtain a copy of the

// License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed

// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR

// CONDITIONS OF ANY KIND, either express or implied.  See the License for the

// specific language governing permissions and limitations under the License.

//----------------------------------------------------------------------------------*/

using System;

using OBS.Model;

using OBS;

using System.Security.Cryptography;

using System.Text;

using System.Net;

using System.IO;

using System.Collections.Generic;

using System.Reflection;



namespace ObsDemo

{

    /// <summary>

    /// This sample demonstrates how to do common operations in temporary signature

    /// way on OBS using the OBS SDK for .NET.

    /// </summary>

    class TemporarySignatureSample

    {



        private static string endpoint = "https://your-endpoint";

        private static string AK = "*** Provide your Access Key ***";

        private static string SK = "*** Provide your Secret Key ***";



        private static ObsClient client;



        private static string bucketName = "my-obs-bucket-demo";

        private static string objectKey = "my-obs-object-key-demo";





        public static void Main(string[] args)

        {

            // Constructs a obs client instance with your account for accessing OBS

            ObsConfig config = new ObsConfig();

            config.Endpoint = endpoint;

            client = new ObsClient(AK, SK, config);



            // Create bucket

            DoCreateBucket();



            // Set/Get/Delete bucket cors

            DoBucketCorsOperations();



            // Create object

            DoCreateObject();



            // Get object

            DoGetObject();



            // Set/Get object acl

            DoObjectAclOperations();



            // Delete object

            DoDeleteObject();



            // Delete bucket

            //DoDeleteBucket();





            Console.ReadKey();

        }





        private static MethodInfo GetAddHeaderInternal()

        {

            return typeof(WebHeaderCollection).GetMethod("AddInternal", BindingFlags.NonPublic | BindingFlags.Instance,

                            null, new Type[] { typeof(string), typeof(string) }, null);

        }



        private static void GetResponse(HttpVerb method, CreateTemporarySignatureResponse response, String content)

        {



            HttpWebRequest webRequest = WebRequest.Create(response.SignUrl) as HttpWebRequest;

            webRequest.Method = method.ToString().ToUpper();





            foreach (KeyValuePair<string, string> header in response.ActualSignedRequestHeaders)

            {

                GetAddHeaderInternal().Invoke(webRequest.Headers, new object[] { header.Key, header.Value });

                //Console.WriteLine("{0}={1}", header.Key, header.Value);

            }



            if (!string.IsNullOrEmpty(content))

            {

                webRequest.SendChunked = true;

                webRequest.AllowWriteStreamBuffering = false;

                using (Stream requestStream = webRequest.GetRequestStream())

                {

                    byte[] buffer = Encoding.UTF8.GetBytes(content);

                    requestStream.Write(buffer, 0, buffer.Length);

                }

            }





            HttpWebResponse webResponse = null;

            try

            {

                webResponse = webRequest.GetResponse() as HttpWebResponse;

            }

            catch (WebException ex)

            {

                webResponse = ex.Response as HttpWebResponse;

            }

            catch(Exception ex)

            {

                Console.WriteLine(ex);

            }



            if(webResponse != null)

            {

                

                if (Convert.ToInt32(webResponse.StatusCode) < 300)

                {

                    Console.WriteLine("Do action successfully with Response Code:" + Convert.ToInt32(webResponse.StatusCode));

                }

                using (MemoryStream dest = new MemoryStream())

                {

                    using (Stream stream = webResponse.GetResponseStream())

                    {

                        byte[] buffer = new byte[8192];

                        int bytesRead;

                        while ((bytesRead = stream.Read(buffer, 0, buffer.Length)) > 0)

                        {

                            dest.Write(buffer, 0, bytesRead);

                        }



                    }

                    Console.WriteLine("Response Content:");

                    Console.WriteLine(Encoding.UTF8.GetString(dest.ToArray()));

                }

            }



        }



        private static void GetResponse(HttpVerb method, CreateTemporarySignatureResponse response)

        {

            GetResponse(method, response, null);

        }



        private static void DoDeleteBucket()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.Method = HttpVerb.DELETE;

            request.Expires = 3600;

            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Deleting bucket using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response);

        }



        private static void DoDeleteObject()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.ObjectKey = objectKey;

            request.Method = HttpVerb.DELETE;

            request.Expires = 3600;

            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Deleting object using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response);

        }



        private static void DoObjectAclOperations()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.ObjectKey = objectKey;

            request.Method = HttpVerb.PUT;

            request.Expires = 3600;

            request.SubResource = SubResourceEnum.Acl;

            request.Headers.Add("x-obs-acl", "public-read");

            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Setting object ACL to public-read using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response);







            request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.ObjectKey = objectKey;

            request.Method = HttpVerb.GET;

            request.Expires = 3600;

            request.SubResource = SubResourceEnum.Acl;

            response = client.CreateTemporarySignature(request);

            Console.WriteLine("Getting object ACL using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response);





        }



        private static void DoGetObject()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.ObjectKey = objectKey;

            request.Method = HttpVerb.GET;

            request.Expires = 3600;

            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Getting object using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response);

        }



        private static void DoCreateObject()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.ObjectKey = objectKey;

            request.Method = HttpVerb.PUT;

            request.Expires = 3600;

            request.Headers.Add("Content-Type", "text/plain");

            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Createing object using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response, "Hello OBS");

        }



        private static void DoBucketCorsOperations()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.Method = HttpVerb.PUT;

            request.Expires = 3600;

            request.SubResource = SubResourceEnum.Cors;

            request.Headers.Add("Content-Type", "application/xml");

            String requestXml = "<CORSConfiguration><CORSRule><AllowedMethod>GET</AllowedMethod><AllowedOrigin>*</AllowedOrigin><AllowedHeader>*</AllowedHeader></CORSRule></CORSConfiguration>";



            request.Headers.Add("Content-MD5", Convert.ToBase64String(new MD5CryptoServiceProvider().ComputeHash(Encoding.UTF8.GetBytes(requestXml))));



            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Setting bucket CORS using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response, requestXml);



            request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.Method = HttpVerb.GET;

            request.Expires = 3600;

            request.SubResource = SubResourceEnum.Cors;

            response = client.CreateTemporarySignature(request);

            Console.WriteLine("Getting bucket CORS using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            GetResponse(request.Method, response);

        }



        private static void DoCreateBucket()

        {

            CreateTemporarySignatureRequest request = new CreateTemporarySignatureRequest();

            request.BucketName = bucketName;

            request.Method = HttpVerb.PUT;

            request.Expires = 3600;

            CreateTemporarySignatureResponse response = client.CreateTemporarySignature(request);

            Console.WriteLine("Creating bucket using temporary signature url:");

            Console.WriteLine("\t" + response.SignUrl);

            string location = "your location";

            String requestXml = "<CreateBucketConfiguration><Location>" + location + "</Location></CreateBucketConfiguration>";

            GetResponse(request.Method, response);

        }

    }



}