using RudderSdk.Core;
using RudderSdk.Core.Abstractions;
using RudderSdk.Core.Models.Auth;

using Xunit;

namespace RudderSdk.Core.Tests;

public sealed class RudderClientTests
{
    [Fact]
    public void Constructor_Composes_All_Runtime_Services()
    {
        var client = CreateClient();

        Assert.NotNull(client.Auth);
        Assert.NotNull(client.Player);
        Assert.NotNull(client.RemoteConfig);
        Assert.NotNull(client.Storage);
        Assert.NotNull(client.Stores);
        Assert.NotNull(client.Leaderboards);
        Assert.NotNull(client.Inventory);
        Assert.NotNull(client.BattlePass);
        Assert.NotNull(client.Quests);
        Assert.NotNull(client.Ugc);
        Assert.NotNull(client.Scenario);
        Assert.NotNull(client.Realtime);
    }

    [Fact]
    public void Constructor_Requires_BaseUrl_And_ProjectKey()
    {
        Assert.Throws<ArgumentException>(() => new RudderClient(new RudderClientOptions { ProjectKey = "key" }));
        Assert.Throws<ArgumentException>(() => new RudderClient(new RudderClientOptions { BaseUrl = "http://localhost" }));
    }

    [Fact]
    public void Constructor_Uses_HttpClientTransport_By_Default()
    {
        var client = new RudderClient(new RudderClientOptions
        {
            BaseUrl = "http://localhost:8082",
            ProjectKey = "project-key"
        });

        Assert.NotNull(client);
    }

    [Fact]
    public async Task Auth_LoginWithDevice_Saves_Tokens_And_Raises_SignedIn()
    {
        var transport = new FakeTransport();
        transport.Responses[typeof(LoginViaDeviceResponse)] = new LoginViaDeviceResponse
        {
            AccessToken = "access-token",
            RefreshToken = "refresh-token"
        };
        var tokenStore = new FakeTokenStore();
        var client = CreateClient(transport: transport, tokenStore: tokenStore);
        var states = new List<RudderAuthState>();
        client.Auth.AuthStateChanged += states.Add;

        await client.Auth.LoginWithDeviceAsync("en", "en", "nickname");

        var request = Assert.IsType<LoginViaDeviceRequest>(transport.LastRequest);
        Assert.Equal("POST", transport.LastMethod);
        Assert.Equal("/sdk/v1/authorization/device", transport.LastPath);
        Assert.Equal("nickname", request.Nickname);
        Assert.Equal("access-token", tokenStore.AccessToken);
        Assert.Equal("refresh-token", tokenStore.RefreshToken);
        Assert.Equal(new[] { RudderAuthState.SignedIn }, states);
    }

    [Fact]
    public void Auth_Logout_Clears_Tokens_And_Raises_SignedOut()
    {
        var tokenStore = new FakeTokenStore { AccessToken = "a", RefreshToken = "r" };
        var client = CreateClient(tokenStore: tokenStore);
        var states = new List<RudderAuthState>();
        client.Auth.AuthStateChanged += states.Add;

        client.Auth.Logout();

        Assert.Null(tokenStore.AccessToken);
        Assert.Null(tokenStore.RefreshToken);
        Assert.Equal(new[] { RudderAuthState.SignedOut }, states);
    }

    [Fact]
    public async Task Realtime_Connect_Returns_Session_From_Injected_Transport()
    {
        var realtimeTransport = new FakeRealtimeTransport();
        var tokenStore = new FakeTokenStore { AccessToken = "access-token" };
        var client = CreateClient(
            tokenStore: tokenStore,
            realtimeTransportFactory: new FakeRealtimeTransportFactory(realtimeTransport));

        var session = await client.Realtime.ConnectAsync();

        Assert.NotNull(session);
        Assert.True(session.IsConnected);
        Assert.Equal("access-token", session.AccessToken);
        Assert.Equal(new Uri("ws://localhost:8090/api/realtime/ws"), realtimeTransport.Uri);
    }

    private static RudderClient CreateClient(
        FakeTransport? transport = null,
        FakeTokenStore? tokenStore = null,
        IRealtimeTransportFactory? realtimeTransportFactory = null)
    {
        return new RudderClient(new RudderClientOptions
        {
            BaseUrl = "http://localhost:8082",
            RealtimeUrl = "ws://localhost:8090/api/realtime/ws",
            ProjectKey = "project-key",
            Transport = transport ?? new FakeTransport(),
            TokenStore = tokenStore ?? new FakeTokenStore(),
            DeviceIdProvider = new FakeDeviceIdProvider(),
            RealtimeTransportFactory = realtimeTransportFactory ?? new FakeRealtimeTransportFactory(new FakeRealtimeTransport())
        });
    }

    internal sealed class FakeTransport : IRudderTransport
    {
        public Dictionary<Type, object> Responses { get; } = new();
        public string? LastMethod { get; private set; }
        public string? LastPath { get; private set; }
        public object? LastRequest { get; private set; }
        public string? LastAccessToken { get; private set; }

        public Task<TResponse> SendAsync<TRequest, TResponse>(
            string method,
            string path,
            TRequest? request,
            string? accessToken,
            CancellationToken cancellationToken = default)
        {
            LastMethod = method;
            LastPath = path;
            LastRequest = request;
            LastAccessToken = accessToken;

            if (Responses.TryGetValue(typeof(TResponse), out var response))
                return Task.FromResult((TResponse)response);

            return Task.FromResult(default(TResponse)!);
        }
    }

    internal sealed class FakeTokenStore : ITokenStore
    {
        public string? AccessToken { get; set; }
        public string? RefreshToken { get; set; }
        public string? GetAccessToken() => AccessToken;
        public string? GetRefreshToken() => RefreshToken;
        public void SaveTokens(string accessToken, string refreshToken)
        {
            AccessToken = accessToken;
            RefreshToken = refreshToken;
        }

        public void Clear()
        {
            AccessToken = null;
            RefreshToken = null;
        }
    }

    private sealed class FakeDeviceIdProvider : IDeviceIdProvider
    {
        public string DeviceId => "device-id";
    }

    private sealed class FakeRealtimeTransportFactory : IRealtimeTransportFactory
    {
        private readonly IRealtimeTransport _transport;

        public FakeRealtimeTransportFactory(IRealtimeTransport transport) => _transport = transport;

        public IRealtimeTransport Create() => _transport;
    }

    private sealed class FakeRealtimeTransport : IRealtimeTransport
    {
        public Uri? Uri { get; private set; }
        public bool IsConnected { get; private set; }
        public event Action? Closed;
        public event Action<Exception>? Error;
        public event Action<ArraySegment<byte>>? Received;

        public Task ConnectAsync(Uri uri, TimeSpan timeout, CancellationToken cancellationToken = default)
        {
            Uri = uri;
            IsConnected = true;
            return Task.CompletedTask;
        }

        public Task SendAsync(ArraySegment<byte> payload, CancellationToken cancellationToken = default)
            => Task.CompletedTask;

        public Task CloseAsync(CancellationToken cancellationToken = default)
        {
            IsConnected = false;
            Closed?.Invoke();
            return Task.CompletedTask;
        }

        public void Update(float deltaTime)
        {
        }

        public void EmitError(Exception ex) => Error?.Invoke(ex);
        public void EmitReceived(ArraySegment<byte> data) => Received?.Invoke(data);
    }
}