using HotelPms.Data;
using Google.Protobuf;
using Grpc.Core;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace HotelPms.GrpcService
{
    public class FileService : FileCore.FileCoreBase
    {
        private readonly ILogger<FileService> _logger;
        private IConfiguration m_Configuration;

        public FileService(ILogger<FileService> logger, IConfiguration configuration)
        {
            _logger = logger;
            m_Configuration = configuration;
        }

        public async override Task DownLoad(FileGrpcHead request, IServerStreamWriter<FileGrpcData> responseStream, ServerCallContext context)
        {
            //1M単位送信する
            string path = System.AppDomain.CurrentDomain.BaseDirectory + @"DownLoad\" + request.FileName;
            if (System.IO.File.Exists(path))
            {
                System.IO.FileInfo fileInfo = new System.IO.FileInfo(path);
                long fileLength = fileInfo.Length;

                using (System.IO.FileStream fs = new System.IO.FileStream(path, System.IO.FileMode.Open, System.IO.FileAccess.Read))
                {
                    using (System.IO.BinaryReader br = new System.IO.BinaryReader(fs))
                    {
                        long offsetFile = 0;
                        long buffSize = 1024 * 1024; //1M
                        long lastBiteSize = fileLength % buffSize;  //余り
                        long currentTimes = 1;
                        long loopTimes = fileLength / buffSize;   //回数
                        if (lastBiteSize > 0) { loopTimes++; }
                        long blockSize = 0;
                        FileGrpcData contentStruct;
                        while (currentTimes <= loopTimes)
                        {
                            fs.Seek(offsetFile, System.IO.SeekOrigin.Begin);
                            if (currentTimes == loopTimes)
                            {
                                blockSize = lastBiteSize;
                            }
                            else
                            {
                                blockSize = buffSize;
                            }

                            byte[] byteArray = br.ReadBytes((int)blockSize);
                            ByteString sbytes = ByteString.CopyFrom(byteArray);
                            contentStruct = new FileGrpcData
                            {
                                FileName = request.FileName,
                                Block = (int)currentTimes,
                                Content = sbytes,
                            };
                            await responseStream.WriteAsync(contentStruct);
                            currentTimes++;
                            offsetFile += blockSize;
                        }
                    }
                }
            }
        }

        public override Task<FileGrpcHead> UpLoad(IAsyncStreamReader<FileGrpcData> requestStream, ServerCallContext context)
        {
            return base.UpLoad(requestStream, context);
        }
    }
}