using System;
using System.Collections.Generic;
using Bogatyri.World;
using NUnit.Framework;

// Тесты модулей без Unity-сцены. Запуск: Window -> General -> Test Runner -> EditMode -> Run All.
// Список тестов, которые команда решила добавить (план от 19.10.2026), -- в Docs/Modules/README.md.
public class ModuleTests
{
    [SetUp]
    public void ResetCore()
    {
        GameServices.Clear();
        EventBus.Clear();
        SaveRegistry.Clear();
    }

    // ---------------- Армия: один солдат не может быть в двух местах ----------------

    [Test]
    public void ArmyMath_TakeProportional_NeverDoubleCountsOrLosesSoldiers()
    {
        var rnd = new Random(1);
        for (int run = 0; run < 2000; run++)
        {
            var troops = new int[4];
            int total = 0;
            for (int i = 0; i < 4; i++) { troops[i] = rnd.Next(0, 50); total += troops[i]; }
            if (total == 0) continue;

            int count = rnd.Next(1, total + 1);
            int[] taken = ArmyMath.TakeProportional(troops, count);

            int sum = 0;
            for (int i = 0; i < 4; i++)
            {
                Assert.That(taken[i], Is.InRange(0, troops[i]), "нельзя взять больше, чем есть в типе");
                sum += taken[i];
            }
            Assert.AreEqual(count, sum, "в поход уходит ровно столько, сколько просили");
        }
    }

    [Test]
    public void ArmyMath_TakeMoreThanExists_ReturnsNull()
    {
        Assert.IsNull(ArmyMath.TakeProportional(new[] { 1, 1, 0, 0 }, 3));
    }

    [Test]
    public void ArmyMath_SplitSurvivors_ReturnsExactlySurvivors()
    {
        int[] back = ArmyMath.SplitSurvivors(new[] { 10, 5, 0, 1 }, 9);
        int sum = 0;
        foreach (var b in back) { Assert.GreaterOrEqual(b, 0); sum += b; }
        Assert.AreEqual(9, sum);
    }

    // ---------------- Боевая система ----------------

    [Test]
    public void Battle_MoreSoldiersWins_TieGoesToDefender()
    {
        var battle = new BattleSystem();
        Assert.IsTrue(battle.Resolve(new BattleRequest { Attackers = 30, Defenders = 20 }).Victory);
        Assert.IsFalse(battle.Resolve(new BattleRequest { Attackers = 20, Defenders = 20 }).Victory);
        Assert.AreEqual(20, battle.Resolve(new BattleRequest { Attackers = 30, Defenders = 20 }).Survivors);
    }

    // ---------------- Глобальный мир: поход до конца, в том числе офлайн ----------------

    [Test]
    public void World_MarchResolvesAndReturns_EvenAfterLongOffline()
    {
        var world = new WorldSimulation(WorldMapLayout.CreateDefault(), new BattleSystem());
        MarchData march = world.StartMarch("p", WorldMapLayout.PlayerCityId, WorldMapLayout.BossCastleId, 30, 0, out string error);
        Assert.IsNotNull(march, error);

        var events = new List<WorldEvent>();
        world.Advance(3_600_000, events); // игра была закрыта час

        Assert.AreEqual(2, events.Count, "бой и возвращение за один вызов");
        Assert.AreEqual(WorldEventType.BattleResolved, events[0].Type);
        Assert.AreEqual(WorldEventType.MarchReturned, events[1].Type);
        Assert.AreEqual(0, world.Marches.Count);
    }

    // ---------------- Чат ----------------

    [Test]
    public void Chat_EmptyMessage_IsRejected()
    {
        var chat = new ChatService(0);
        int before = chat.GetMessages(ChatChannel.World).Count;
        Assert.IsFalse(chat.Send(ChatChannel.World, "   "));
        Assert.AreEqual(before, chat.GetMessages(ChatChannel.World).Count);
    }

    [Test]
    public void Chat_Send_TrimsCutsAndPublishesEvent()
    {
        var chat = new ChatService(0);
        ChatMessage received = null;
        EventBus.Subscribe<ChatMessageReceivedEvent>(e => received = e.Message);

        Assert.IsTrue(chat.Send(ChatChannel.Circle, "  " + new string('а', 500) + "  "));

        Assert.IsNotNull(received, "событие о новом сообщении");
        Assert.AreEqual(ChatChannel.Circle, received.channel);
        Assert.AreEqual(LocalPlayer.Id, received.senderId);
        Assert.AreEqual(chat.MaxMessageLength, received.text.Length, "длинное сообщение обрезается");
    }

    [Test]
    public void Chat_KeepsOnlyLastMessagesPerChannel()
    {
        var chat = new ChatService(0);
        for (int i = 0; i < 250; i++) chat.Send(ChatChannel.World, "сообщение " + i);

        var world = chat.GetMessages(ChatChannel.World);
        Assert.AreEqual(ChatService.MaxStoredPerChannel, world.Count);
        Assert.AreEqual("сообщение 249", world[world.Count - 1].text);
    }

    // ---------------- Круг ----------------

    [Test]
    public void Circle_CreateMakesPlayerLeader_AndCannotJoinSecond()
    {
        var circle = new CircleService();
        Assert.IsFalse(circle.IsInCircle);

        Assert.IsTrue(circle.TryCreate("  Дружина  ", out string error), error);
        Assert.IsTrue(circle.IsInCircle);
        Assert.IsTrue(circle.IsLeader);
        Assert.AreEqual("Дружина", circle.Current.name);

        Assert.IsFalse(circle.TryJoin("circle_1", out _), "нельзя состоять в двух Кругах");
        Assert.IsFalse(circle.TryCreate("Ещё один", out _));
    }

    [Test]
    public void Circle_NameValidation()
    {
        var circle = new CircleService();
        Assert.IsFalse(circle.TryCreate("ab", out _), "слишком короткое");
        Assert.IsFalse(circle.TryCreate(new string('я', 30), out _), "слишком длинное");
        Assert.IsFalse(circle.TryCreate("Круг Перуна", out _), "такое название уже есть");
        Assert.IsFalse(circle.TryCreate("a|b<c>", out _), "недопустимые символы");
    }

    [Test]
    public void Circle_JoinFullCircle_IsRejected()
    {
        var circle = new CircleService();
        CircleInfo full = circle.GetCircles()[circle.GetCircles().Count - 1];
        Assert.AreEqual(circle.MaxMembers, full.members.Count);
        Assert.IsFalse(circle.TryJoin(full.id, out _));
    }

    [Test]
    public void Circle_LeaveAlone_Disbands_LeaveAsMember_KeepsCircle()
    {
        var circle = new CircleService();
        int before = circle.GetCircles().Count;
        bool disbanded = false;
        EventBus.Subscribe<CircleLeftEvent>(e => disbanded = e.Disbanded);

        circle.TryCreate("Дружина", out _);
        circle.Leave();
        Assert.IsTrue(disbanded);
        Assert.AreEqual(before, circle.GetCircles().Count, "свой Круг распущен");

        circle.TryJoin("circle_1", out _);
        int members = circle.Current.members.Count;
        circle.Leave();
        Assert.IsFalse(disbanded);
        Assert.AreEqual(members - 1, circle.GetCircles()[0].members.Count);
    }

    [Test]
    public void Circle_SaveAndRestore_KeepsMembership()
    {
        var a = new CircleService();
        a.TryCreate("Дружина", out _);
        string saved = a.Capture();

        var b = new CircleService();
        b.Restore(saved);
        Assert.IsTrue(b.IsInCircle);
        Assert.IsTrue(b.IsLeader);
        Assert.AreEqual("Дружина", b.Current.name);

        var c = new CircleService();
        c.TryJoin("circle_3", out _);
        var d = new CircleService();
        d.Restore(c.Capture());
        Assert.AreEqual("circle_3", d.Current.id);
        Assert.IsFalse(d.IsLeader);
    }

    [Test]
    public void Chat_CircleChannel_OnlyWhenInCircle()
    {
        var circle = new CircleService();
        GameServices.Register<ICircle>(circle);
        var chat = new ChatService(0);

        Assert.IsFalse(chat.Send(ChatChannel.Circle, "привет"), "без Круга писать нельзя");
        circle.TryJoin("circle_1", out _);
        Assert.AreEqual(1, chat.GetMessages(ChatChannel.Circle).Count, "системное сообщение о вступлении");
        Assert.IsTrue(chat.Send(ChatChannel.Circle, "привет"));
        Assert.IsTrue(chat.Send(ChatChannel.World, "всем привет"), "общий чат доступен всегда");
    }

    // ---------------- Ядро ----------------

    [Test]
    public void EventBus_FailingSubscriberDoesNotBreakOthers()
    {
        int delivered = 0;
        Exception caught = null;
        EventBus.OnHandlerError = e => caught = e;
        EventBus.Subscribe<MarchReturnedEvent>(_ => throw new InvalidOperationException("boom"));
        EventBus.Subscribe<MarchReturnedEvent>(_ => delivered++);

        EventBus.Publish(new MarchReturnedEvent { Survivors = 5 });

        Assert.AreEqual(1, delivered);
        Assert.IsNotNull(caught);
    }

    [Test]
    public void GameServices_MissingModule_ThrowsClearError()
    {
        Assert.Throws<InvalidOperationException>(() => GameServices.Get<IArmy>());
        Assert.IsFalse(GameServices.TryGet(out IArmy _));
    }
}