using NUnit.Framework;
using SVSim.BattleNode.Bridge;
using SVSim.BattleNode.Sessions;
using SVSim.BattleNode.Sessions.Dispatch;

namespace SVSim.UnitTests.BattleNode.Sessions;

[TestFixture]
public class BattleSessionStateTests
{
    private sealed class StubParticipant : IBattleParticipant
    {
        public long ViewerId { get; }
        public MatchContext Context { get; }
        public event Func<SVSim.BattleNode.Protocol.MsgEnvelope, CancellationToken, Task>? FrameEmitted;
        public StubParticipant(long id, MatchContext ctx) { ViewerId = id; Context = ctx; }
        public Task PushAsync(SVSim.BattleNode.Protocol.MsgEnvelope e, Stock n, CancellationToken c) => Task.CompletedTask;
        public Task RunAsync(CancellationToken c) => Task.CompletedTask;
        public Task TerminateAsync(BattleFinishReason r) => Task.CompletedTask;
        public ValueTask DisposeAsync() => ValueTask.CompletedTask;
        private void Touch() => FrameEmitted?.Invoke(null!, default);
    }

    private static MatchContext Ctx(params long[] deck) => new(
        SelfDeckCardIds: deck, ClassId: CardClass.Forestcraft, CharaId: "1", CardMasterName: "cm",
        CountryCode: CountryCodes.Korea, UserName: "P", SleeveId: "0", EmblemId: "0", DegreeId: "0",
        FieldId: 0, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo);

    [Test]
    public void GetOrSeedDeckMap_maps_idx_1based_to_the_shuffled_order()
    {
        // The map seeds from GetShuffledDeck, not raw build order. idx (i+1) -> shuffledDeck[i],
        // and the set of cardIds is unchanged (1..3 present, 4 absent).
        var state = new BattleSessionState(masterSeed: 12345);
        var p = new StubParticipant(1, Ctx(900L, 901L, 902L));
        var shuffled = state.GetShuffledDeck(p);

        var map = state.GetOrSeedDeckMap(p);

        Assert.That(map[1], Is.EqualTo(shuffled[0]));
        Assert.That(map[2], Is.EqualTo(shuffled[1]));
        Assert.That(map[3], Is.EqualTo(shuffled[2]));
        Assert.That(map.ContainsKey(4), Is.False);
        Assert.That(new[] { map[1], map[2], map[3] }, Is.EquivalentTo(new[] { 900L, 901L, 902L }));
    }

    [Test]
    public void GetOrSeedDeckMap_is_idempotent_same_instance()
    {
        var state = new BattleSessionState();
        var p = new StubParticipant(1, Ctx(900L));
        Assert.That(state.GetOrSeedDeckMap(p), Is.SameAs(state.GetOrSeedDeckMap(p)));
    }

    [Test]
    public void GetShuffledDeck_is_a_permutation_of_the_input()
    {
        var state = new BattleSessionState(masterSeed: 12345);
        var p = new StubParticipant(1001, Ctx(DistinctDeck()));

        Assert.That(state.GetShuffledDeck(p), Is.EquivalentTo(DistinctDeck()),
            "same multiset of cards, just reordered");
    }

    [Test]
    public void GetShuffledDeck_actually_reorders_a_distinct_deck()
    {
        var state = new BattleSessionState(masterSeed: 12345);
        var p = new StubParticipant(1001, Ctx(DistinctDeck()));

        Assert.That(state.GetShuffledDeck(p), Is.Not.EqualTo(DistinctDeck()),
            "a 30-card distinct deck should not survive the shuffle in original order");
    }

    [Test]
    public void GetShuffledDeck_is_deterministic_for_same_master_seed_and_viewer()
    {
        var a = new BattleSessionState(masterSeed: 777).GetShuffledDeck(new StubParticipant(1001, Ctx(DistinctDeck())));
        var b = new BattleSessionState(masterSeed: 777).GetShuffledDeck(new StubParticipant(1001, Ctx(DistinctDeck())));
        Assert.That(a, Is.EqualTo(b));
    }

    [Test]
    public void GetShuffledDeck_differs_across_master_seeds()
    {
        var a = new BattleSessionState(masterSeed: 1).GetShuffledDeck(new StubParticipant(1001, Ctx(DistinctDeck())));
        var b = new BattleSessionState(masterSeed: 2).GetShuffledDeck(new StubParticipant(1001, Ctx(DistinctDeck())));
        Assert.That(a, Is.Not.EqualTo(b));
    }

    [Test]
    public void RecordSpellboostFrom_accumulates_add_ops_and_routes_by_isSelf()
    {
        var state = new BattleSessionState(masterSeed: 1);
        var caster = new StubParticipant(7, Ctx(900L));
        var oppo = new StubParticipant(6, Ctx(901L));

        // Two spell-plays each grant +1 to the caster's hand card idx 3 (the classic spellboost ramp).
        var grant = new List<object?> { new Dictionary<string, object?>
            { ["alter"] = new Dictionary<string, object?>
                { ["idx"] = new List<object?> { 3L }, ["isSelf"] = 1L, ["type"] = "add", ["spellboost"] = "a1" } } };
        state.RecordSpellboostFrom(caster, oppo, grant);
        state.RecordSpellboostFrom(caster, oppo, grant);

        Assert.That(state.GetSpellboostMap(caster)[3], Is.EqualTo(2), "two +1 grants accumulate");
        Assert.That(state.GetSpellboostMap(oppo).ContainsKey(3), Is.False, "isSelf:1 routes to the caster only");
    }

    [Test]
    public void Boosted_card_carries_real_spellboost_into_its_knownList()
    {
        // End-to-end regression for the 2026-06-05 desync: a spellboosted card whose relayed knownList
        // shipped spellboost:0 made the opponent compute full cost and silently reject the play. After the
        // grant is recorded, BuildPlayedCard must emit the accumulated count, not 0.
        var state = new BattleSessionState(masterSeed: 1);
        var caster = new StubParticipant(7, Ctx(101311010L, 999L, 998L));   // idx 1..3 deck-seeded

        var grant = new List<object?> { new Dictionary<string, object?>
            { ["alter"] = new Dictionary<string, object?>
                { ["idx"] = new List<object?> { 3L }, ["isSelf"] = 1L, ["type"] = "add", ["spellboost"] = "a1" } } };
        state.RecordSpellboostFrom(caster, new StubParticipant(6, Ctx(901L)), grant);

        // idx 3 is now played hand->board; its knownList must reflect the +1.
        var play = new List<object?> { new Dictionary<string, object?>
            { ["move"] = new Dictionary<string, object?>
                { ["idx"] = new List<object?> { 3L }, ["isSelf"] = 1L, ["from"] = 10L, ["to"] = 20L } } };
        var entry = KnownListBuilder.BuildPlayedCard(
            state.GetOrSeedDeckMap(caster), playIdx: 3, orderList: play, state.GetSpellboostMap(caster));

        Assert.That(entry, Is.Not.Null);
        Assert.That(entry!.Spellboost, Is.EqualTo(1));
    }

    private static long[] DistinctDeck() =>
        Enumerable.Range(1, 30).Select(i => 200_000_000L + i).ToArray();
}