using Vanguard.Server.Realtime;

namespace Vanguard.Server.Tests;

public class HeartbeatStateTests
{
    private static readonly DateTimeOffset Start = new(2026, 10, 21, 12, 0, 0, TimeSpan.Zero);
    private static readonly TimeSpan Idle = TimeSpan.FromSeconds(20);
    private static readonly TimeSpan Timeout = TimeSpan.FromSeconds(20);

    [Fact]
    public void Server_Pings_After_Idle_And_Closes_After_Timeout()
    {
        var state = new HeartbeatState(Start);

        Assert.Equal(HeartbeatActionKind.None, state.Evaluate(Start, Idle, Timeout).Kind);
        Assert.Equal(HeartbeatActionKind.None,
            state.Evaluate(Start.AddSeconds(19), Idle, Timeout).Kind);

        var ping = state.Evaluate(Start.AddSeconds(20), Idle, Timeout);
        Assert.Equal(HeartbeatActionKind.Ping, ping.Kind);
        Assert.Equal(1, ping.Nonce);

        Assert.Equal(HeartbeatActionKind.None,
            state.Evaluate(Start.AddSeconds(30), Idle, Timeout).Kind);

        Assert.Equal(HeartbeatActionKind.Timeout,
            state.Evaluate(Start.AddSeconds(40), Idle, Timeout).Kind);
    }

    [Fact]
    public void Any_Frame_Resets_The_Idle_Timer()
    {
        var state = new HeartbeatState(Start);

        state.Evaluate(Start.AddSeconds(20), Idle, Timeout); // ping отправлен
        state.Touch(Start.AddSeconds(25));                    // клиент ответил

        Assert.Equal(HeartbeatActionKind.None,
            state.Evaluate(Start.AddSeconds(44), Idle, Timeout).Kind);

        var next = state.Evaluate(Start.AddSeconds(45), Idle, Timeout);
        Assert.Equal(HeartbeatActionKind.Ping, next.Kind);
        Assert.Equal(2, next.Nonce);
    }
}