using Google.Protobuf;
using Grpc.Core;
using GrpcService1;
using Ips.Service.CpuServer;
using Microsoft.AspNetCore.Hosting;
using System.IO;

namespace GrpcService1.Services
{
    public class FileService : Ips.Service.CpuServer.FileOper.FileOperBase
    {
        public override async Task<UploadFileResponse> UploadFile(
          IAsyncStreamReader<UploadFileRequest> requestStream, ServerCallContext context)
        {
            var requests = new Queue<UploadFileRequest>();
            while (await requestStream.MoveNext())
            {
                var request = requestStream.Current;
                requests.Enqueue(request);
            }

            var first = requests.Peek();
            var fileExt = Path.GetExtension(first.FileName);
            var fileName = $"{Guid.NewGuid().ToString()}{fileExt}";
            var filePath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Upload", fileName);

            var fileFolder = Directory.GetParent(filePath);
            if (fileFolder != null && !fileFolder.Exists)
                fileFolder.Create();

            using (var fileStream = File.Open(filePath, FileMode.Append, FileAccess.Write))
            {
                var received = 0L;
                while (requests.Count() > 0)
                {
                    var current = requests.Dequeue();
                    var buffer = current.Content.ToByteArray();
                    fileStream.Seek(received, SeekOrigin.Begin);
                    await fileStream.WriteAsync(buffer);
                    received += buffer.Length;
                }

                return new UploadFileResponse() { FilePath = $"/Upload/{fileName}" };
            }
        }


        public override async Task DownloadFile(DownloadFileRequest request,
  IServerStreamWriter<DownloadFileResponse> responseStream, ServerCallContext context)
        {
            var filePath = Path.Combine(Directory.GetCurrentDirectory(), request.FilePath);
            if (File.Exists(filePath))
            {
                using (var fileStream = File.OpenRead(filePath))
                {

                    var received = 0L;
                    var totalLength = fileStream.Length;

                    var buffer = new byte[1024 * 1024]; // 每次最多发送 1M 的文件内容
                    while (received < totalLength)
                    {
                        var length = await fileStream.ReadAsync(buffer);
                        received += length;
                        var response = new DownloadFileResponse()
                        {
                            Content = ByteString.CopyFrom(buffer),
                            TotalSize = totalLength
                        };

                        await responseStream.WriteAsync(response);
                    }
                }
            }
        }
        public override Task<HelloReply> Test(HelloRequest request, ServerCallContext context)
        {
            return Task.FromResult(new HelloReply
            {
                Message = "Hello " + request.Name
            });
        }
    }
}