using Google.Protobuf.WellKnownTypes;
using MxGateway.Client.Cli;
using MxGateway.Contracts.Proto;
using MxGateway.Contracts.Proto.Galaxy;

namespace MxGateway.Client.Tests;

/// <summary>Tests for the CLI command interface.</summary>
public sealed class MxGatewayClientCliTests
{
    /// <summary>Verifies that the version command prints compiled protocol versions.</summary>
    [Fact]
    public void Run_Version_PrintsCompiledProtocolVersions()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();

        var exitCode = MxGatewayClientCli.Run(["version"], output, error);

        Assert.Equal(0, exitCode);
        Assert.Contains("gateway-protocol=3", output.ToString());
        Assert.Contains("worker-protocol=1", output.ToString());
        Assert.Equal(string.Empty, error.ToString());
    }

    /// <summary>Verifies that the version command with --json flag prints JSON protocol versions.</summary>
    [Fact]
    public async Task RunAsync_VersionJson_PrintsJsonProtocolVersions()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();

        int exitCode = await MxGatewayClientCli.RunAsync(["version", "--json"], output, error);

        Assert.Equal(0, exitCode);
        Assert.Contains("\"gatewayProtocolVersion\":3", output.ToString());
        Assert.Equal(string.Empty, error.ToString());
    }

    /// <summary>Verifies that the write command builds a write request and prints JSON reply.</summary>
    [Fact]
    public async Task RunAsync_Write_BuildsWriteCommandAndPrintsJsonReply()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new();
        fakeClient.InvokeReplies.Enqueue(new MxCommandReply
        {
            SessionId = "session-fixture",
            Kind = MxCommandKind.Write,
            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
        });

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "write",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
                "--session-id",
                "session-fixture",
                "--server-handle",
                "12",
                "--item-handle",
                "34",
                "--type",
                "int32",
                "--value",
                "123",
                "--json",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(0, exitCode);
        MxCommandRequest request = Assert.Single(fakeClient.InvokeRequests);
        Assert.Equal(MxCommandKind.Write, request.Command.Kind);
        Assert.Equal(123, request.Command.Write.Value.Int32Value);
        Assert.Contains("MX_COMMAND_KIND_WRITE", output.ToString());
        Assert.Equal(string.Empty, error.ToString());
    }

    /// <summary>Verifies that error output redacts sensitive API key values.</summary>
    [Fact]
    public async Task RunAsync_ErrorOutput_RedactsApiKey()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "open-session",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "secret-api-key",
            ],
            output,
            error,
            _ => throw new InvalidOperationException("boom secret-api-key"));

        Assert.Equal(1, exitCode);
        Assert.DoesNotContain("secret-api-key", error.ToString());
        Assert.Contains("[redacted]", error.ToString());
    }

    /// <summary>Verifies that stream-events with max-events limit stops output in non-JSON format.</summary>
    [Fact]
    public async Task RunAsync_StreamEvents_WithMaxEventsStopsNonJsonOutput()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new();
        fakeClient.Events.Add(new MxEvent
        {
            SessionId = "session-fixture",
            Family = MxEventFamily.OnDataChange,
            WorkerSequence = 1,
        });
        fakeClient.Events.Add(new MxEvent
        {
            SessionId = "session-fixture",
            Family = MxEventFamily.OnWriteComplete,
            WorkerSequence = 2,
        });

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "stream-events",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
                "--session-id",
                "session-fixture",
                "--max-events",
                "1",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(0, exitCode);
        Assert.Contains("workerSequence", output.ToString());
        Assert.DoesNotContain("ON_WRITE_COMPLETE", output.ToString());
    }


    /// <summary>Verifies that smoke command closes opened session when a command fails.</summary>
    [Fact]
    public async Task RunAsync_Smoke_WhenCommandFails_ClosesOpenedSession()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new()
        {
            InvokeFailure = new InvalidOperationException("register failed"),
        };

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "smoke",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
                "--item",
                "Area001.Pump001.Speed",
                "--json",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(1, exitCode);
        CloseSessionRequest closeRequest = Assert.Single(fakeClient.CloseSessionRequests);
        Assert.Equal("session-fixture", closeRequest.SessionId);
    }

    /// <summary>Verifies that galaxy-test-connection command prints JSON reply.</summary>
    [Fact]
    public async Task RunAsync_GalaxyTestConnection_PrintsJsonReply()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new()
        {
            GalaxyTestConnectionReply = new TestConnectionReply { Ok = true },
        };

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "galaxy-test-connection",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
                "--json",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(0, exitCode);
        Assert.Single(fakeClient.GalaxyTestConnectionRequests);
        Assert.Contains("\"ok\": true", output.ToString());
        Assert.Equal(string.Empty, error.ToString());
    }

    /// <summary>Verifies that galaxy-discover command prints hierarchy summary.</summary>
    [Fact]
    public async Task RunAsync_GalaxyDiscover_PrintsHierarchySummary()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new();
        fakeClient.GalaxyDiscoverHierarchyReplies.Enqueue(new DiscoverHierarchyReply
        {
            NextPageToken = "7:1",
            TotalObjectCount = 2,
            Objects =
            {
                new GalaxyObject
                {
                    GobjectId = 7,
                    TagName = "DelmiaReceiver_001",
                    ContainedName = "DelmiaReceiver",
                    ParentGobjectId = 1,
                    Attributes =
                    {
                        new GalaxyAttribute
                        {
                            AttributeName = "DownloadPath",
                            FullTagReference = "DelmiaReceiver_001.DownloadPath",
                        },
                    },
                },
            },
        });
        fakeClient.GalaxyDiscoverHierarchyReplies.Enqueue(new DiscoverHierarchyReply
        {
            TotalObjectCount = 2,
            Objects =
            {
                new GalaxyObject
                {
                    GobjectId = 8,
                    TagName = "DelmiaReceiver_002",
                    ContainedName = "DelmiaReceiver",
                    ParentGobjectId = 1,
                },
            },
        });

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "galaxy-discover",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(0, exitCode);
        Assert.Equal(2, fakeClient.GalaxyDiscoverHierarchyRequests.Count);
        Assert.Equal(5000, fakeClient.GalaxyDiscoverHierarchyRequests[0].PageSize);
        Assert.Equal("", fakeClient.GalaxyDiscoverHierarchyRequests[0].PageToken);
        Assert.Equal("7:1", fakeClient.GalaxyDiscoverHierarchyRequests[1].PageToken);
        string text = output.ToString();
        Assert.Contains("objects=2", text);
        Assert.Contains("DelmiaReceiver_001", text);
        Assert.Contains("DelmiaReceiver_002", text);
        Assert.Contains("attributes=1", text);
        Assert.Equal(string.Empty, error.ToString());
    }

    /// <summary>Verifies that galaxy-watch command prints text output for deploy events.</summary>
    [Fact]
    public async Task RunAsync_GalaxyWatch_PrintsTextOutputForEvents()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new();
        DateTime deploy = new(2026, 4, 28, 14, 30, 0, DateTimeKind.Utc);
        fakeClient.GalaxyDeployEvents.Add(new DeployEvent
        {
            Sequence = 1,
            ObservedAt = Timestamp.FromDateTime(deploy),
            TimeOfLastDeploy = Timestamp.FromDateTime(deploy),
            TimeOfLastDeployPresent = true,
            ObjectCount = 5,
            AttributeCount = 17,
        });
        fakeClient.GalaxyDeployEvents.Add(new DeployEvent
        {
            Sequence = 2,
            ObservedAt = Timestamp.FromDateTime(deploy.AddSeconds(30)),
            TimeOfLastDeploy = Timestamp.FromDateTime(deploy.AddSeconds(30)),
            TimeOfLastDeployPresent = true,
            ObjectCount = 6,
            AttributeCount = 18,
        });

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "galaxy-watch",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
                "--last-seen-deploy-time",
                "2026-04-28T14:00:00Z",
                "--max-events",
                "2",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(0, exitCode);
        WatchDeployEventsRequest request = Assert.Single(fakeClient.GalaxyWatchDeployEventsRequests);
        Assert.NotNull(request.LastSeenDeployTime);
        string text = output.ToString();
        Assert.Contains("sequence=1", text);
        Assert.Contains("sequence=2", text);
        Assert.Contains("objects=5", text);
        Assert.Contains("attributes=18", text);
        Assert.Equal(string.Empty, error.ToString());
    }

    /// <summary>Verifies that galaxy-watch with --json emits one JSON object per event.</summary>
    [Fact]
    public async Task RunAsync_GalaxyWatch_JsonEmitsOneObjectPerEvent()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
        FakeCliClient fakeClient = new();
        fakeClient.GalaxyDeployEvents.Add(new DeployEvent
        {
            Sequence = 42,
            ObjectCount = 99,
            AttributeCount = 1024,
        });

        int exitCode = await MxGatewayClientCli.RunAsync(
            [
                "galaxy-watch",
                "--endpoint",
                "http://localhost:5000",
                "--api-key",
                "test-api-key",
                "--max-events",
                "1",
                "--json",
            ],
            output,
            error,
            _ => fakeClient);

        Assert.Equal(0, exitCode);
        string text = output.ToString();
        Assert.Contains("\"sequence\": \"42\"", text);
        Assert.Contains("\"objectCount\": 99", text);
    }

    /// <summary>Fake CLI client for testing.</summary>
    private sealed class FakeCliClient : IMxGatewayCliClient
    {
        /// <summary>Queue of invoke replies to return.</summary>
        public Queue<MxCommandReply> InvokeReplies { get; } = new();

        /// <summary>List of received invoke requests.</summary>
        public List<MxCommandRequest> InvokeRequests { get; } = [];

        /// <summary>List of received close session requests.</summary>
        public List<CloseSessionRequest> CloseSessionRequests { get; } = [];

        /// <summary>List of events to yield when streaming.</summary>
        public List<MxEvent> Events { get; } = [];

        /// <summary>Exception to throw on invoke, if any.</summary>
        public Exception? InvokeFailure { get; init; }

        /// <inheritdoc />
        public ValueTask DisposeAsync()
        {
            return ValueTask.CompletedTask;
        }

        /// <inheritdoc />
        public Task<OpenSessionReply> OpenSessionAsync(
            OpenSessionRequest request,
            CancellationToken cancellationToken)
        {
            return Task.FromResult(new OpenSessionReply
            {
                SessionId = "session-fixture",
                ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
                GatewayProtocolVersion = 1,
                WorkerProtocolVersion = 1,
            });
        }

        /// <inheritdoc />
        public Task<CloseSessionReply> CloseSessionAsync(
            CloseSessionRequest request,
            CancellationToken cancellationToken)
        {
            CloseSessionRequests.Add(request);
            return Task.FromResult(new CloseSessionReply
            {
                SessionId = request.SessionId,
                ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
                FinalState = SessionState.Closed,
            });
        }

        /// <inheritdoc />
        public Task<MxCommandReply> InvokeAsync(
            MxCommandRequest request,
            CancellationToken cancellationToken)
        {
            InvokeRequests.Add(request);
            if (InvokeFailure is not null)
            {
                throw InvokeFailure;
            }

            return Task.FromResult(InvokeReplies.Dequeue());
        }

        /// <inheritdoc />
        public async IAsyncEnumerable<MxEvent> StreamEventsAsync(
            StreamEventsRequest request,
            [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken)
        {
            foreach (MxEvent gatewayEvent in Events)
            {
                cancellationToken.ThrowIfCancellationRequested();
                await Task.Yield();
                yield return gatewayEvent;
            }
        }

        /// <summary>Galaxy test connection reply to return.</summary>
        public TestConnectionReply GalaxyTestConnectionReply { get; set; } = new() { Ok = true };

        /// <summary>Galaxy get last deploy time reply to return.</summary>
        public GetLastDeployTimeReply GalaxyGetLastDeployTimeReply { get; set; } = new() { Present = false };

        /// <summary>Galaxy discover hierarchy reply to return.</summary>
        public DiscoverHierarchyReply GalaxyDiscoverHierarchyReply { get; set; } = new();

        public Queue<DiscoverHierarchyReply> GalaxyDiscoverHierarchyReplies { get; } = new();

        /// <summary>List of received galaxy test connection requests.</summary>
        public List<TestConnectionRequest> GalaxyTestConnectionRequests { get; } = [];

        /// <summary>List of received galaxy get last deploy time requests.</summary>
        public List<GetLastDeployTimeRequest> GalaxyGetLastDeployTimeRequests { get; } = [];

        /// <summary>List of received galaxy discover hierarchy requests.</summary>
        public List<DiscoverHierarchyRequest> GalaxyDiscoverHierarchyRequests { get; } = [];

        /// <inheritdoc />
        public Task<TestConnectionReply> GalaxyTestConnectionAsync(
            TestConnectionRequest request,
            CancellationToken cancellationToken)
        {
            GalaxyTestConnectionRequests.Add(request);
            return Task.FromResult(GalaxyTestConnectionReply);
        }

        /// <inheritdoc />
        public Task<GetLastDeployTimeReply> GalaxyGetLastDeployTimeAsync(
            GetLastDeployTimeRequest request,
            CancellationToken cancellationToken)
        {
            GalaxyGetLastDeployTimeRequests.Add(request);
            return Task.FromResult(GalaxyGetLastDeployTimeReply);
        }

        /// <inheritdoc />
        public Task<DiscoverHierarchyReply> GalaxyDiscoverHierarchyAsync(
            DiscoverHierarchyRequest request,
            CancellationToken cancellationToken)
        {
            GalaxyDiscoverHierarchyRequests.Add(request);
            return Task.FromResult(
                GalaxyDiscoverHierarchyReplies.TryDequeue(out DiscoverHierarchyReply? reply)
                    ? reply
                    : GalaxyDiscoverHierarchyReply);
        }

        /// <summary>List of received galaxy watch deploy events requests.</summary>
        public List<WatchDeployEventsRequest> GalaxyWatchDeployEventsRequests { get; } = [];

        /// <summary>List of deploy events to yield when watching.</summary>
        public List<DeployEvent> GalaxyDeployEvents { get; } = [];

        /// <inheritdoc />
        public async IAsyncEnumerable<DeployEvent> GalaxyWatchDeployEventsAsync(
            WatchDeployEventsRequest request,
            [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken)
        {
            GalaxyWatchDeployEventsRequests.Add(request);
            foreach (DeployEvent deployEvent in GalaxyDeployEvents)
            {
                cancellationToken.ThrowIfCancellationRequested();
                await Task.Yield();
                yield return deployEvent;
            }
        }
    }
}