using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.IO;


namespace Sog.IO
{
    /// <summary>
    /// protobuf保存成文件，某些不是很重要的服务器数据可以采用这种方法保存，丢了也无所谓的
    /// </summary>
    public static class FileDBSave
    {
        public static int SaveToFile(Google.Protobuf.IMessage message,string filepath)
        {
            try
            {
                byte[] dataByte = Google.Protobuf.MessageExtensions.ToByteArray(message);

                FileStream fileStream = File.OpenWrite(filepath);
                //清空文件
                fileStream.SetLength(0);

                BinaryWriter sw = new BinaryWriter(fileStream);
                sw.Write(dataByte);
                sw.Flush();
                sw.Dispose();
                fileStream.Dispose();
                return 0;
            }
            catch (Exception ex)
            {
                TraceLog.Error("FileDBSave.SaveToFile write file failed! {0}", filepath);
                TraceLog.Exception(ex);
                return -2;
            }
        }

        public static Google.Protobuf.IMessage ReadFromFile(Google.Protobuf.MessageParser parser,string filepath)
        {
            if (File.Exists(filepath) == false)
            {
                //这个不能算错误
                TraceLog.Debug("FileDBSave.ReadFromFile file not exist {0}", filepath);
                return null;
            }

            try
            {
                byte[] data = File.ReadAllBytes(filepath);
                Google.Protobuf.IMessage message = parser.ParseFrom(data);

                return message;
            }
            catch(Exception ex)
            {
                TraceLog.Error("FileDBSave.ReadFromFile parse message failed! {0}", filepath);
                TraceLog.Exception(ex);
                return null;
            }

        }

        public static int SaveToFile<T>(ref T structMessage, string filepath)
            where T : struct, ProtoCSStruct.IStructMessage<T>
        {
            try
            {
                int size = structMessage.CalculateSize();
                byte[] dataByte = new byte[size];
                ProtoCSStruct.CodedOutputStream ouput = new ProtoCSStruct.CodedOutputStream(dataByte);
                structMessage.WriteTo(ouput);

                FileStream fileStream = File.OpenWrite(filepath);
                //清空文件
                fileStream.SetLength(0);

                BinaryWriter sw = new BinaryWriter(fileStream);
                sw.Write(dataByte);
                sw.Flush();
                sw.Dispose();
                fileStream.Dispose();
                return 0;
            }
            catch (Exception ex)
            {
                TraceLog.Error("FileDBSave.SaveToFile write file failed! {0}", filepath);
                TraceLog.Exception(ex);
                return -2;
            }
        }

        public static bool ReadFromFile<T>(ref T structMessage, string filepath)
            where T : struct, ProtoCSStruct.IStructMessage<T>
        {
            if (File.Exists(filepath) == false)
            {
                //这个不能算错误
                TraceLog.Debug("FileDBSave.ReadFromFile file not exist {0}", filepath);
                return false;
            }

            try
            {
                byte[] data = File.ReadAllBytes(filepath);
                ProtoCSStruct.CodedInputStream input = new ProtoCSStruct.CodedInputStream(data);
                structMessage.ReadFrom(input);

                return true;
            }
            catch (Exception ex)
            {
                TraceLog.Error("FileDBSave.ReadFromFile parse message failed! {0}", filepath);
                TraceLog.Exception(ex);
                return false;
            }

        }
    }

    public static class FileDBSaveByBinSerialize
    {
        public static int SaveToFile(object obj, string filepath)
        {
            try
            {
                byte[] dataByte = BinarySerialize.BinSerialize.Serialize(obj);

                FileStream fileStream = File.OpenWrite(filepath);
                //清空文件
                fileStream.SetLength(0);

                BinaryWriter sw = new BinaryWriter(fileStream);
                sw.Write(dataByte);
                sw.Flush();
                sw.Dispose();
                fileStream.Dispose();
                return 0;
            }
            catch (Exception ex)
            {
                TraceLog.Error("FileDBSaveByBinSerialize.SaveToFile write file failed! {0}", filepath);
                TraceLog.Exception(ex);
                return -2;
            }
        }

        public static T ReadFromFile<T>(string filepath)where T : class
        {
            if (File.Exists(filepath) == false)
            {
                //这个不能算错误
                TraceLog.Debug("FileDBSaveByBinSerialize.ReadFromFile file not exist {0}", filepath);
                return null;
            }

            try
            {
                byte[] data = File.ReadAllBytes(filepath);
                return BinarySerialize.BinSerialize.Deserialize<T>(data);
            }
            catch (Exception ex)
            {
                TraceLog.Error("FileDBSaveByBinSerialize.ReadFromFile parse message failed! {0}", filepath);
                TraceLog.Exception(ex);
                return null;
            }

        }
    }
}