using NUnit.Framework;
using BaseGames.AI;
using BaseGames.Enemies;

namespace BaseGames.Tests.EditMode.AI
{
    public class DeathModuleTests
    {
        // 从一个活着的态出发，发 Died 信号进入死亡链。
        static AiRuntime RunWithDeath(IDeathModule m, FakeAiContext ctx)
        {
            var b = new BrainBuilder();
            AiStateFragments.Locomotion(b, "Alive", LocomotionMode.Patrol);
            m.Build(b);
            b.Entry("Alive");
            b.Global().To(m.EntryState).OnEvent(AiSignal.Died);
            return new AiRuntime(b.Build(), ctx);
        }

        [Test]
        public void TerminalDeath_EntersAndStays_NoAbility()
        {
            var ctx = new FakeAiContext();
            var rt = RunWithDeath(new TerminalDeath(), ctx);
            rt.Send(AiSignal.Died);
            rt.Tick(0.1f);
            Assert.AreEqual(TerminalDeath.Death, rt.CurrentStateName);
            Assert.AreEqual(0, ctx.C.Used.Count);          // 演出走物理状态机，AI 不触发能力
            rt.Tick(0.1f);
            Assert.AreEqual(TerminalDeath.Death, rt.CurrentStateName);
        }

        [Test]
        public void AbilityDeath_TriggersOnce_DoesNotLoop()
        {
            var ctx = new FakeAiContext();
            var rt = RunWithDeath(new AbilityDeath("die"), ctx);
            rt.Send(AiSignal.Died);
            rt.Tick(0.1f);
            Assert.AreEqual(1, ctx.C.Used.Count);
            ctx.C.Running = null;                          // 演出播完
            rt.Tick(0.1f); rt.Tick(0.1f);
            Assert.AreEqual(1, ctx.C.Used.Count);          // 不重播
        }

        [Test]
        public void TwoStageDeath_PreThenFinal()
        {
            var ctx = new FakeAiContext();
            var rt = RunWithDeath(new TwoStageDeath("die_pre", "die"), ctx);
            rt.Send(AiSignal.Died);
            rt.Tick(0.1f);
            Assert.AreEqual(TwoStageDeath.DeathPre, rt.CurrentStateName);
            CollectionAssert.Contains(ctx.C.Used, "die_pre");

            rt.Tick(0.1f);
            Assert.AreEqual(TwoStageDeath.DeathPre, rt.CurrentStateName);  // 前段还在跑

            ctx.C.Running = null;                          // 前段结束
            rt.Tick(0.1f);
            Assert.AreEqual(TwoStageDeath.Death, rt.CurrentStateName);
            CollectionAssert.Contains(ctx.C.Used, "die");
        }

        [Test]
        public void AbilityDeath_Build_Throws_WhenAbilityMissing()
        {
            var b = new BrainBuilder();
            Assert.Throws<System.InvalidOperationException>(() => new AbilityDeath().Build(b));
        }
    }
}