using NUnit.Framework;
using ProjectM.Server;
using ProjectM.Simulation;
using Unity.Collections;
using Unity.Core;
using Unity.Entities;
using Unity.Mathematics;
using Unity.NetCode;
using Unity.Transforms;

namespace ProjectM.Tests
{
    /// <summary>
    /// Plain-Entities EditMode tests for the server-only <see cref="ZoneEnemyDirectorSystem"/>. A bare world is
    /// seeded with NetworkTime, a CycleDirector entity (CycleState + CycleRuntime) and a zone-enemy director
    /// (ZoneEnemyDirector + ZoneEnemyState + a Prefab-tagged enemy in the ZoneEnemyPrefab buffer). Pins: it spawns
    /// only while a player is OUT in the expedition AND the base is Calm; tags spawns RegionTag{Expedition} +
    /// ZoneEnemyTag at the deterministic ring origin (Scale preserved); and marks CycleRuntime.ClearedThisEpoch on a
    /// real clear.
    /// </summary>
    public class ZoneEnemyDirectorSystemTests
    {
        static (World world, SimulationSystemGroup group, Entity cycle) MakeWorld(string name, uint serverTick, byte phase, int epoch)
        {
            var world = new World(name);
            var group = world.GetOrCreateSystemManaged<SimulationSystemGroup>();
            group.AddSystemToUpdateList(world.GetOrCreateSystem<ZoneEnemyDirectorSystem>());
            group.SortSystems();
            world.SetTime(new TimeData(elapsedTime: 0f, deltaTime: 1f / 60f));
            var em = world.EntityManager;
            var nt = em.CreateEntity(typeof(NetworkTime));
            em.SetComponentData(nt, new NetworkTime { ServerTick = new NetworkTick(serverTick) });
            var cyc = em.CreateEntity(typeof(CycleState), typeof(CycleRuntime));
            em.SetComponentData(cyc, new CycleState { Phase = phase });
            em.SetComponentData(cyc, new CycleRuntime { ExpeditionEpoch = epoch });
            return (world, group, cyc);
        }

        static Entity MakeZonePrefab(EntityManager em)
        {
            var e = em.CreateEntity(typeof(LocalTransform), typeof(EnemyTag));
            em.SetComponentData(e, LocalTransform.Identity); // Scale = 1 so WithPosition keeps it
            em.AddComponent<Prefab>(e);
            return e;
        }

        static Entity MakeDirector(EntityManager em, Entity grunt, Entity charger,
            int maxAlive, int gruntsPerWave, int chargersPerWave,
            uint nextSpawnTick, int remainingToSpawn, int seededEpoch, uint spawnCounter)
        {
            var e = em.CreateEntity(typeof(ZoneEnemyDirector), typeof(ZoneEnemyState));
            em.SetComponentData(e, new ZoneEnemyDirector
            {
                MaxAlive = maxAlive, RingRadius = 14f, RingSlots = 10, SpawnIntervalTicks = 10,
                GruntsPerWave = gruntsPerWave, ChargersPerWave = chargersPerWave, RewardOre = 25,
            });
            em.SetComponentData(e, new ZoneEnemyState
            {
                SpawnCounter = spawnCounter, RemainingToSpawn = remainingToSpawn,
                NextSpawnTick = nextSpawnTick, SeededEpoch = seededEpoch,
            });
            var buf = em.AddBuffer<ZoneEnemyPrefab>(e);
            buf.Add(new ZoneEnemyPrefab { Prefab = grunt });
            buf.Add(new ZoneEnemyPrefab { Prefab = charger });
            return e;
        }

        static Entity MakeExpeditionPlayer(EntityManager em, float3 pos)
        {
            var e = em.CreateEntity();
            em.AddComponentData(e, new RegionTag { Region = RegionId.Expedition });
            em.AddComponentData(e, LocalTransform.FromPosition(pos));
            em.AddComponent<PlayerTag>(e);
            return e;
        }

        static int ZoneCount(EntityManager em)
        {
            using var q = em.CreateEntityQuery(typeof(ZoneEnemyTag));
            return q.CalculateEntityCount();
        }

        [Test]
        public void Spawns_Expedition_Tagged_Enemy_When_Occupied_And_Calm()
        {
            var (world, group, _) = MakeWorld("ZoneSpawn", serverTick: 100, phase: CyclePhase.Calm, epoch: 1);
            using (world)
            {
                var em = world.EntityManager;
                var grunt = MakeZonePrefab(em);
                var charger = MakeZonePrefab(em);
                var dir = MakeDirector(em, grunt, charger, maxAlive: 12, gruntsPerWave: 2, chargersPerWave: 0,
                    nextSpawnTick: 0, remainingToSpawn: 0, seededEpoch: 0, spawnCounter: 0);
                MakeExpeditionPlayer(em, new float3(1000, 1, 0));

                group.Update();

                Assert.AreEqual(1, ZoneCount(em), "one zone enemy spawns this tick");
                using var q = em.CreateEntityQuery(typeof(ZoneEnemyTag), typeof(RegionTag));
                var arr = q.ToComponentDataArray<RegionTag>(Allocator.Temp);
                Assert.AreEqual(RegionId.Expedition, arr[0].Region, "the spawn is tagged RegionTag{Expedition}");
                arr.Dispose();

                var zs = em.GetComponentData<ZoneEnemyState>(dir);
                Assert.AreEqual(1u, zs.SpawnCounter, "spawn counter advanced");
                Assert.AreEqual(1, zs.RemainingToSpawn, "wave size 2 seeded, 1 spawned -> 1 remaining");
            }
        }

        [Test]
        public void Spawn_Lands_On_Expedition_Ring_Origin_With_Scale_Preserved()
        {
            var (world, group, _) = MakeWorld("ZoneRing", serverTick: 100, phase: CyclePhase.Calm, epoch: 1);
            using (world)
            {
                var em = world.EntityManager;
                var grunt = MakeZonePrefab(em);
                var charger = MakeZonePrefab(em);
                MakeDirector(em, grunt, charger, maxAlive: 12, gruntsPerWave: 2, chargersPerWave: 0,
                    nextSpawnTick: 0, remainingToSpawn: 0, seededEpoch: 0, spawnCounter: 0);
                MakeExpeditionPlayer(em, new float3(1000, 1, 0));

                group.Update();

                using var q = em.CreateEntityQuery(typeof(ZoneEnemyTag), typeof(LocalTransform));
                var arr = q.ToComponentDataArray<LocalTransform>(Allocator.Temp);
                // origin = base(0,1,0) + (1000,0,0); ring slot 0 of a 10-slot radius-14 ring -> +X.
                Assert.AreEqual(1014f, arr[0].Position.x, 1e-2f, "deterministic ring slot 0 at the expedition origin (+radius on X)");
                Assert.AreEqual(1f, arr[0].Scale, 1e-3f, "baked Scale preserved (WithPosition, not FromPosition)");
                arr.Dispose();
            }
        }

        [Test]
        public void Does_Not_Spawn_When_No_Expedition_Player()
        {
            var (world, group, _) = MakeWorld("ZoneEmpty", serverTick: 100, phase: CyclePhase.Calm, epoch: 1);
            using (world)
            {
                var em = world.EntityManager;
                var grunt = MakeZonePrefab(em);
                var charger = MakeZonePrefab(em);
                MakeDirector(em, grunt, charger, maxAlive: 12, gruntsPerWave: 2, chargersPerWave: 0,
                    nextSpawnTick: 0, remainingToSpawn: 0, seededEpoch: 0, spawnCounter: 0);
                // no expedition player out there

                group.Update();

                Assert.AreEqual(0, ZoneCount(em), "nobody out in the expedition -> nothing spawns");
            }
        }

        [Test]
        public void Does_Not_Spawn_During_Base_Siege()
        {
            var (world, group, _) = MakeWorld("ZoneSiege", serverTick: 100, phase: CyclePhase.Siege, epoch: 1);
            using (world)
            {
                var em = world.EntityManager;
                var grunt = MakeZonePrefab(em);
                var charger = MakeZonePrefab(em);
                MakeDirector(em, grunt, charger, maxAlive: 12, gruntsPerWave: 2, chargersPerWave: 0,
                    nextSpawnTick: 0, remainingToSpawn: 0, seededEpoch: 0, spawnCounter: 0);
                MakeExpeditionPlayer(em, new float3(1000, 1, 0));

                group.Update();

                Assert.AreEqual(0, ZoneCount(em), "the expedition wave pauses while the base is under siege (Calm-only spawning)");
            }
        }

        [Test]
        public void Cleared_Wave_Marks_ClearedThisEpoch()
        {
            var (world, group, cyc) = MakeWorld("ZoneCleared", serverTick: 100, phase: CyclePhase.Calm, epoch: 1);
            using (world)
            {
                var em = world.EntityManager;
                var grunt = MakeZonePrefab(em);
                var charger = MakeZonePrefab(em);
                // already seeded this epoch + fully spawned (RemainingToSpawn 0) + no live zone enemies.
                MakeDirector(em, grunt, charger, maxAlive: 12, gruntsPerWave: 2, chargersPerWave: 0,
                    nextSpawnTick: 0, remainingToSpawn: 0, seededEpoch: 1, spawnCounter: 2);
                MakeExpeditionPlayer(em, new float3(1000, 1, 0));

                group.Update();

                Assert.AreEqual((byte)1, em.GetComponentData<CycleRuntime>(cyc).ClearedThisEpoch,
                    "wave fully spawned + no live zone enemies -> a real clear is marked");
            }
        }
    }
}