using NUnit.Framework;
using SVSim.BattleNode.Lifecycle;
using SVSim.BattleNode.Protocol;
using SVSim.BattleNode.Protocol.Bodies;
using SVSim.BattleNode.Sessions;
using SVSim.BattleNode.Sessions.Participants;

namespace SVSim.UnitTests.BattleNode.Sessions.Participants;

[TestFixture]
public class ScriptedBotParticipantTests
{
    [Test]
    public async Task RunAsync_emits_InitNetwork_to_kick_off_handshake()
    {
        var p = new ScriptedBotParticipant();
        var emitted = new List<NetworkBattleUri>();
        p.FrameEmitted += (env, _) => { emitted.Add(env.Uri); return Task.CompletedTask; };

        await p.RunAsync(CancellationToken.None);

        Assert.That(emitted, Is.EqualTo(new[] { NetworkBattleUri.InitNetwork }));
    }

    [TestCase(NetworkBattleUri.InitNetwork, NetworkBattleUri.InitBattle)]
    [TestCase(NetworkBattleUri.Matched, NetworkBattleUri.Loaded)]
    [TestCase(NetworkBattleUri.Deal, NetworkBattleUri.Swap)]
    public async Task PushAsync_handshake_push_emits_next_client_frame(
        NetworkBattleUri pushed, NetworkBattleUri expectedEmit)
    {
        var p = new ScriptedBotParticipant();
        var emitted = new List<NetworkBattleUri>();
        p.FrameEmitted += (env, _) => { emitted.Add(env.Uri); return Task.CompletedTask; };

        await p.PushAsync(NewEnvelope(pushed), noStock: false, CancellationToken.None);

        Assert.That(emitted, Is.EqualTo(new[] { expectedEmit }));
    }

    [Test]
    public async Task PushAsync_TurnEnd_fires_three_FrameEmitted_in_order()
    {
        var p = new ScriptedBotParticipant();
        var emitted = new List<NetworkBattleUri>();
        p.FrameEmitted += (env, _) => { emitted.Add(env.Uri); return Task.CompletedTask; };

        await p.PushAsync(NewEnvelope(NetworkBattleUri.TurnEnd), noStock: false, CancellationToken.None);

        Assert.That(emitted, Is.EqualTo(new[]
        {
            NetworkBattleUri.TurnStart, NetworkBattleUri.TurnEnd, NetworkBattleUri.Judge,
        }));
    }

    [Test]
    public async Task PushAsync_non_reactive_uris_emit_nothing()
    {
        var p = new ScriptedBotParticipant();
        var fired = 0;
        p.FrameEmitted += (_, _) => { fired++; return Task.CompletedTask; };

        foreach (var uri in new[]
        {
            NetworkBattleUri.BattleStart, NetworkBattleUri.Swap, NetworkBattleUri.Ready,
            NetworkBattleUri.PlayActions, NetworkBattleUri.TurnStart, NetworkBattleUri.Echo,
            NetworkBattleUri.Judge, NetworkBattleUri.BattleFinish, NetworkBattleUri.TurnEndFinal,
        })
        {
            await p.PushAsync(NewEnvelope(uri), noStock: false, CancellationToken.None);
        }

        Assert.That(fired, Is.EqualTo(0));
    }

    [Test]
    public void Implements_IHasHandshakePhase_starting_at_AwaitingInitNetwork()
    {
        var p = new ScriptedBotParticipant();
        Assert.That(p, Is.InstanceOf<IHasHandshakePhase>());
        Assert.That(((IHasHandshakePhase)p).Phase, Is.EqualTo(BattleSessionPhase.AwaitingInitNetwork));
    }

    private static MsgEnvelope NewEnvelope(NetworkBattleUri uri) =>
        new(uri, ViewerId: 1, Uuid: "u", Bid: null, Try: 0,
            Cat: EmitCategory.Battle, PubSeq: null, PlaySeq: null,
            Body: new ResultCodeOnlyBody());
}