using System.Threading.Tasks;
using FrostFS.SDK.ClientV2.Mappers.GRPC.Netmap;
using FrostFS.Container;

using FrostFS.SDK.ClientV2.Mappers.GRPC;
using FrostFS.SDK.Cryptography;
using System.Collections.Generic;
using FrostFS.SDK.ModelsV2;
using FrostFS.Refs;
using System;
using FrostFS.SDK.ClientV2.Parameters;
using System.Collections.Specialized;

namespace FrostFS.SDK.ClientV2;

internal class ContainerServiceProvider : ContextAccessor
{
    private readonly ContainerService.ContainerServiceClient containerServiceClient;
    
    internal ContainerServiceProvider(ContainerService.ContainerServiceClient service, ClientEnvironment context)
        : base(context)
    {
        containerServiceClient = service;
    }

    internal async Task<ModelsV2.Container> GetContainerAsync(PrmContainerGet args)
    {
        GetRequest request = GetContainerRequest(args.ContainerId.ToGrpcMessage(), args.XHeaders);

        var response = await containerServiceClient.GetAsync(request, null, args.Context!.Deadline, args.Context.CancellationToken);

        Verifier.CheckResponse(response);

        return response.Body.Container.ToModel();
    }

    internal async IAsyncEnumerable<ContainerId> ListContainersAsync(PrmContainerGetAll args)
    {
        var ctx = args.Context!;

        var request = new ListRequest
        {
            Body = new ListRequest.Types.Body
            {
                OwnerId = Context.Owner.ToGrpcMessage()
            }
        };
        
        request.AddMetaHeader(args.XHeaders);
        request.Sign(Context.Key);

        var response = await containerServiceClient.ListAsync(request, null, ctx.Deadline, ctx.CancellationToken);
       
        Verifier.CheckResponse(response);
       
        foreach (var cid in response.Body.ContainerIds)
        {
            yield return new ContainerId(Base58.Encode(cid.Value.ToByteArray()));
        }
    }

    internal async Task<ContainerId> CreateContainerAsync(PrmContainerCreate args)
    {
        var ctx = args.Context!;
        var grpcContainer = args.Container.ToGrpcMessage(); 
        grpcContainer.OwnerId = Context.Owner.ToGrpcMessage();
        grpcContainer.Version = Context.Version.ToGrpcMessage();
        
        var request = new PutRequest
        {
            Body = new PutRequest.Types.Body
            {
                Container = grpcContainer,
                Signature = Context.Key.SignRFC6979(grpcContainer)               
            }
        };
        
        request.AddMetaHeader(args.XHeaders);
        request.Sign(Context.Key);

        var response = await containerServiceClient.PutAsync(request, null, ctx.Deadline, ctx.CancellationToken);
      
        Verifier.CheckResponse(response);

        await WaitForContainer(WaitExpects.Exists, response.Body.ContainerId, args.WaitParams, ctx);
      
        return new ContainerId(Base58.Encode(response.Body.ContainerId.Value.ToByteArray()));
    }

    internal async Task DeleteContainerAsync(PrmContainerDelete args)
    {
        var ctx = args.Context!;
        var request = new DeleteRequest
        {
            Body = new DeleteRequest.Types.Body
            {
                ContainerId = args.ContainerId.ToGrpcMessage(),
                Signature = Context.Key.SignRFC6979(args.ContainerId.ToGrpcMessage().Value)
            }
        };
    
        request.AddMetaHeader(args.XHeaders);
        request.Sign(Context.Key);

        var response = await containerServiceClient.DeleteAsync(request, null, ctx.Deadline, ctx.CancellationToken);

        await WaitForContainer(WaitExpects.Removed, request.Body.ContainerId, args.WaitParams, ctx);
    
        Verifier.CheckResponse(response);
    }

    private GetRequest GetContainerRequest(ContainerID id, NameValueCollection? xHeaders)
    {
        var request = new GetRequest
        {
            Body = new GetRequest.Types.Body
            {
                ContainerId = id
            }
        };

        request.AddMetaHeader(xHeaders);
        request.Sign(Context.Key);

        return request;
    }

    private enum WaitExpects
    { 
        Exists,
        Removed
    }

    private async Task WaitForContainer(WaitExpects expect, ContainerID id, PrmWait? waitParams, Context ctx)
    {
        var request = GetContainerRequest(id, null);

        async Task action()
        {
            var response = await containerServiceClient.GetAsync(request, null, ctx.Deadline, ctx.CancellationToken);
            Verifier.CheckResponse(response);
        }

        await WaitFor(action, expect, waitParams);
    }

    private static async Task WaitFor(
        Func<Task> action,
        WaitExpects expect,
        PrmWait? waitParams)
    { 
        waitParams ??= PrmWait.DefaultParams;
        var deadLine = waitParams.GetDeadline();

        while (true)
        {
            try
            {
                await action();

                if (expect == WaitExpects.Exists)
                    return;
                
                await Task.Delay(waitParams.PollInterval);
            }
            catch (ResponseException ex)
            {
                if (DateTime.UtcNow >= deadLine)
                    throw new TimeoutException();

                if (ex.Status.Code != ModelsV2.Enums.StatusCode.ContainerNotFound)
                    throw;

                if (expect == WaitExpects.Removed)
                    return;
                
                await Task.Delay(waitParams.PollInterval);
            }
        }
    }
}