// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System.Linq;
using System.Threading.Tasks;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using MQTTnet.Formatter;
using MQTTnet.Protocol;
using MQTTnet.Server;
using MQTTnet.Tests.Mockups;

namespace MQTTnet.Tests.Server;

// ReSharper disable InconsistentNaming
[TestClass]
public sealed class Status_Tests : BaseTestClass
{
    [TestMethod]
    public async Task Disconnect_Client()
    {
        using var testEnvironment = new TestEnvironment(TestContext);
        var server = await testEnvironment.StartServer();

        var c1 = await testEnvironment.ConnectClient(new MqttClientOptionsBuilder().WithClientId("client1"));

        await Task.Delay(1000);

        var clientStatus = await server.GetClientsAsync();

        Assert.HasCount(1, clientStatus);
        Assert.IsTrue(clientStatus.Any(s => s.Id == c1.Options.ClientId));

        await clientStatus[0].DisconnectAsync();

        await Task.Delay(500);

        Assert.IsFalse(c1.IsConnected);

        clientStatus = await server.GetClientsAsync();

        Assert.IsEmpty(clientStatus);
    }

    [TestMethod]
    public async Task Keep_Persistent_Session_Version311()
    {
        using var testEnvironment = new TestEnvironment(TestContext);
        var server = await testEnvironment.StartServer(o => o.WithPersistentSessions());

        var c1 = await testEnvironment.ConnectClient(
            new MqttClientOptionsBuilder().WithClientId("client1").WithCleanSession(false).WithProtocolVersion(MqttProtocolVersion.V311));
        var c2 = await testEnvironment.ConnectClient(
            new MqttClientOptionsBuilder().WithClientId("client2").WithCleanSession(false).WithProtocolVersion(MqttProtocolVersion.V311));

        await c1.DisconnectAsync();

        await LongTestDelay();

        var clientStatus = await server.GetClientsAsync();
        var sessionStatus = await server.GetSessionsAsync();

        Assert.HasCount(1, clientStatus);
        Assert.HasCount(2, sessionStatus);

        await c2.DisconnectAsync();

        await LongTestDelay();

        clientStatus = await server.GetClientsAsync();
        sessionStatus = await server.GetSessionsAsync();

        Assert.IsEmpty(clientStatus);
        Assert.HasCount(2, sessionStatus);
    }

    [TestMethod]
    public async Task Keep_Persistent_Session_Version500()
    {
        using var testEnvironment = new TestEnvironment(TestContext);
        var server = await testEnvironment.StartServer(o => o.WithPersistentSessions());

        var c1 = await testEnvironment.ConnectClient(
            new MqttClientOptionsBuilder().WithClientId("client1").WithCleanSession(false).WithProtocolVersion(MqttProtocolVersion.V500));
        var c2 = await testEnvironment.ConnectClient(
            new MqttClientOptionsBuilder().WithClientId("client2").WithCleanSession(false).WithProtocolVersion(MqttProtocolVersion.V500));

        // The session expiry interval is mandatory for MQTT5.0.0 in order keep session!
        await c1.DisconnectAsync(sessionExpiryInterval: 60);

        await LongTestDelay();

        var clientStatus = await server.GetClientsAsync();
        var sessionStatus = await server.GetSessionsAsync();

        Assert.HasCount(1, clientStatus);
        Assert.HasCount(2, sessionStatus);

        // The session expiry interval is mandatory for MQTT5.0.0 in order keep session!
        await c2.DisconnectAsync(sessionExpiryInterval: 60);

        await LongTestDelay();

        clientStatus = await server.GetClientsAsync();
        sessionStatus = await server.GetSessionsAsync();

        Assert.IsEmpty(clientStatus);
        Assert.HasCount(2, sessionStatus);
    }

    [TestMethod]
    public async Task Show_Client_And_Session_Statistics()
    {
        using var testEnvironment = new TestEnvironment(TestContext);
        var server = await testEnvironment.StartServer();

        var c1 = await testEnvironment.ConnectClient(new MqttClientOptionsBuilder().WithClientId("client1"));
        var c2 = await testEnvironment.ConnectClient(new MqttClientOptionsBuilder().WithClientId("client2"));

        await Task.Delay(500);

        var clientStatus = await server.GetClientsAsync();
        var sessionStatus = await server.GetSessionsAsync();

        Assert.HasCount(2, clientStatus);
        Assert.HasCount(2, sessionStatus);

        Assert.IsTrue(clientStatus.Any(s => s.Id == c1.Options.ClientId));
        Assert.IsTrue(clientStatus.Any(s => s.Id == c2.Options.ClientId));

        await c1.DisconnectAsync();
        await c2.DisconnectAsync();

        await Task.Delay(500);

        clientStatus = await server.GetClientsAsync();
        sessionStatus = await server.GetSessionsAsync();

        Assert.IsEmpty(clientStatus);
        Assert.IsEmpty(sessionStatus);
    }

    [TestMethod]
    public async Task Track_Sent_Application_Messages()
    {
        using var testEnvironment = new TestEnvironment(TestContext);
        var server = await testEnvironment.StartServer(new MqttServerOptionsBuilder().WithPersistentSessions());

        var c1 = await testEnvironment.ConnectClient();

        for (var i = 1; i < 25; i++)
        {
            await c1.PublishStringAsync("a");
            await Task.Delay(50);

            var clientStatus = await server.GetClientsAsync();
            Assert.AreEqual(i, clientStatus[0].SentApplicationMessagesCount);
            Assert.AreEqual(0, clientStatus[0].ReceivedApplicationMessagesCount);
        }
    }

    [TestMethod]
    public async Task Track_Sent_Packets()
    {
        using var testEnvironment = new TestEnvironment(TestContext);
        var server = await testEnvironment.StartServer(new MqttServerOptionsBuilder().WithPersistentSessions());

        var c1 = await testEnvironment.ConnectClient(new MqttClientOptionsBuilder().WithNoKeepAlive());

        for (var i = 1; i < 25; i++)
        {
            // At most once will send one packet to the client and the server will reply
            // with an additional ACK packet.
            await c1.PublishStringAsync("a", string.Empty, MqttQualityOfServiceLevel.AtLeastOnce);

            await Task.Delay(500);

            var clientStatus = await server.GetClientsAsync();

            Assert.AreEqual(i, clientStatus[0].SentApplicationMessagesCount, "SAMC invalid!");

            // + 1 because CONNECT is also counted.
            Assert.AreEqual(i + 1, clientStatus[0].SentPacketsCount, "SPC invalid!");

            // +2 because ConnACK + PubAck package is already counted.
            Assert.AreEqual(i + 2, clientStatus[0].ReceivedPacketsCount, "RPC invalid!");
        }
    }
}