using Account;
using Grpc.Core;
using Grpc.Net.Client;
using Palace;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Numerics;
using System.Threading;
using System.Threading.Tasks;

namespace Pal.Client
{
    internal class RemoteApi : IDisposable
    {
#if DEBUG
        private const string remoteUrl = "http://localhost:5145";
#else
        private const string remoteUrl = "https://pal.μ.tv:47701";
#endif
        private GrpcChannel _channel;
        private string _authToken;
        private DateTime _tokenExpiresAt;

        private async Task<bool> Connect(CancellationToken cancellationToken)
        {
            if (Service.Configuration.Mode != Configuration.EMode.Online)
                return false;

            if (_channel == null || !(_channel.State == ConnectivityState.Ready || _channel.State == ConnectivityState.Idle))
            {
                Dispose();

                _channel = GrpcChannel.ForAddress(remoteUrl, new GrpcChannelOptions
                {
                    HttpHandler = new SocketsHttpHandler
                    {
                        ConnectTimeout = TimeSpan.FromSeconds(5),
                    }
                });
                await _channel.ConnectAsync(cancellationToken);
            }

            var accountClient = new AccountService.AccountServiceClient(_channel);
            string accountId = Service.Configuration.AccountId;
            if (string.IsNullOrEmpty(accountId))
            {
                var createAccountReply = await accountClient.CreateAccountAsync(new CreateAccountRequest(), deadline: DateTime.UtcNow.AddSeconds(10), cancellationToken: cancellationToken);
                if (createAccountReply.Success)
                {
                    Service.Configuration.AccountId = accountId = createAccountReply.AccountId;
                    Service.Configuration.Save();
                }
            }

            if (string.IsNullOrEmpty(accountId))
                return false;

            if (string.IsNullOrEmpty(_authToken) || _tokenExpiresAt < DateTime.Now)
            {
                var loginReply = await accountClient.LoginAsync(new LoginRequest { AccountId = accountId }, deadline: DateTime.UtcNow.AddSeconds(10), cancellationToken: cancellationToken);
                if (loginReply.Success)
                {
                    _authToken = loginReply.AuthToken;
                    _tokenExpiresAt = loginReply.ExpiresAt.ToDateTime().ToLocalTime();
                }
            }

            return !string.IsNullOrEmpty(_authToken);
        }

        public async Task<string> VerifyConnection(CancellationToken cancellationToken = default)
        {
            if (!await Connect(cancellationToken))
                return "Could not connect to server";

            var accountClient = new AccountService.AccountServiceClient(_channel);
            await accountClient.VerifyAsync(new VerifyRequest(), headers: AuthorizedHeaders(), deadline: DateTime.UtcNow.AddSeconds(10), cancellationToken: cancellationToken);
            return "Connection successful";
        }

        public async Task<(bool, List<Marker>)> DownloadRemoteMarkers(ushort territoryId, CancellationToken cancellationToken = default)
        {
            if (!await Connect(cancellationToken))
                return (false, new());

            var palaceClient = new PalaceService.PalaceServiceClient(_channel);
            var downloadReply = await palaceClient.DownloadFloorsAsync(new DownloadFloorsRequest { TerritoryType = territoryId }, headers: AuthorizedHeaders(), cancellationToken: cancellationToken);
            return (downloadReply.Success, downloadReply.Objects.Select(o => new Marker(o.Type, new Vector3(o.X, o.Y, o.Z)) { RemoteSeen = true }).ToList());
        }

        public async Task<bool> UploadMarker(ushort territoryType, IList<Marker> markers, CancellationToken cancellationToken = default)
        {
            if (markers.Count == 0)
                return true;

            if (!await Connect(cancellationToken))
                return false;

            var palaceClient = new PalaceService.PalaceServiceClient(_channel);
            var uploadRequest = new UploadFloorsRequest
            {
                TerritoryType = territoryType,
            };
            uploadRequest.Objects.AddRange(markers.Select(m => new PalaceObject
            {
                Type = m.Type,
                X = m.Position.X,
                Y = m.Position.Y,
                Z = m.Position.Z
            }));
            var uploadReply = await palaceClient.UploadFloorsAsync(uploadRequest, headers: AuthorizedHeaders(), cancellationToken: cancellationToken);
            return uploadReply.Success;
        }

        private Metadata AuthorizedHeaders() => new Metadata
        {
            { "Authorization", $"Bearer {_authToken}" },
        };

        public void Dispose()
        {
            _channel?.Dispose();
            _channel = null;
        }
    }
}