#nullable enable

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using Cysharp.Threading.Tasks;

namespace ShrinkNetwork
{
    public sealed class ShrinkNetworkSession
    {
        private readonly ConcurrentDictionary<string, object> _items = new();
        private readonly ConcurrentDictionary<string, byte> _permissions = new();

        internal ShrinkNetworkSession(long sessionId, string remoteAddress, ShrinkNetworkService service)
        {
            SessionId = sessionId;
            RemoteAddress = remoteAddress;
            Service = service;
        }

        public long SessionId { get; }
        public string RemoteAddress { get; internal set; }
        public ShrinkNetworkService Service { get; }
        public ShrinkNetworkPeerKind PeerKind { get; private set; } = ShrinkNetworkPeerKind.Unknown;
        public string SessionToken { get; private set; } = string.Empty;
        public DateTimeOffset? SessionTokenExpiresAtUtc { get; private set; }

        public IDictionary<string, object> Items => _items;

        public void SetPeerKind(ShrinkNetworkPeerKind peerKind)
        {
            PeerKind = peerKind;
        }

        public void SetSessionToken(string sessionToken, DateTimeOffset? expiresAtUtc = null)
        {
            SessionToken = string.IsNullOrWhiteSpace(sessionToken) ? string.Empty : sessionToken.Trim();
            SessionTokenExpiresAtUtc = string.IsNullOrWhiteSpace(SessionToken) ? null : expiresAtUtc;
        }

        public void ClearSessionToken()
        {
            SessionToken = string.Empty;
            SessionTokenExpiresAtUtc = null;
        }

        public void GrantPermission(string permission)
        {
            if (!string.IsNullOrWhiteSpace(permission))
                _permissions[permission.Trim()] = 0;
        }

        public void RevokePermission(string permission)
        {
            if (!string.IsNullOrWhiteSpace(permission))
                _permissions.TryRemove(permission.Trim(), out _);
        }

        public bool HasPermission(string permission)
        {
            return !string.IsNullOrWhiteSpace(permission) && _permissions.ContainsKey(permission.Trim());
        }

        public IReadOnlyCollection<string> GetPermissions() => _permissions.Keys.ToArray();

        public UniTask SendAsync<TMessage>(TMessage message, string? route = null)
            where TMessage : IShrinkNetworkMessage
            => Service.SendAsync(this, message, route);

        public UniTask SendAsync(IShrinkNetworkMessage message, string? route = null)
            => Service.SendAsync(this, message, route);

        public UniTask NotifyAsync<TMessage>(TMessage message, string? route = null)
            where TMessage : IShrinkNetworkMessage
            => Service.SendAsync(this, message, route);

        public UniTask NotifyAsync(IShrinkNetworkMessage message, string? route = null)
            => Service.SendAsync(this, message, route);

        public UniTask<TResponse> CallAsync<TRequest, TResponse>(TRequest request, string? route = null)
            where TRequest : IShrinkNetworkRequest
            where TResponse : class, IShrinkNetworkResponse
            => Service.CallAsync<TRequest, TResponse>(this, request, route);

        public UniTask<TResponse> CallAsync<TRequest, TResponse>(TRequest request, ShrinkRpcCallOptions options)
            where TRequest : IShrinkNetworkRequest
            where TResponse : class, IShrinkNetworkResponse
            => Service.CallAsync<TRequest, TResponse>(this, request, options);

        public UniTask<TResponse> RpcAsync<TRequest, TResponse>(TRequest request, string? route = null)
            where TRequest : IShrinkNetworkRequest
            where TResponse : class, IShrinkNetworkResponse
            => Service.CallAsync<TRequest, TResponse>(this, request, route);

        public UniTask<TResponse> RpcAsync<TRequest, TResponse>(TRequest request, ShrinkRpcCallOptions options)
            where TRequest : IShrinkNetworkRequest
            where TResponse : class, IShrinkNetworkResponse
            => Service.CallAsync<TRequest, TResponse>(this, request, options);

        public UniTask<TResponse> RpcAsync<TRequest, TResponse>(TRequest request, int timeoutMs,
            CancellationToken cancellationToken = default)
            where TRequest : IShrinkNetworkRequest
            where TResponse : class, IShrinkNetworkResponse
            => Service.CallAsync<TRequest, TResponse>(this, request, new ShrinkRpcCallOptions
            {
                TimeoutMs = timeoutMs,
                CancellationToken = cancellationToken
            });
    }
}