using ProjectM.Simulation;
using Unity.Core;
using Unity.Entities;
using Unity.Mathematics;
using Unity.NetCode;
using Unity.Transforms;

namespace ProjectM.Tests
{
    /// <summary>
    /// Plain-Entities EditMode harness. Behaviourally identical to the hand-rolled MakeWorld/SetServerTick idioms
    /// scattered across the suite (a NetworkTime-seeded SimulationSystemGroup world), consolidated so the boilerplate
    /// has one home. Named NOT to end in "Tests" so the attribute-guard meta-test skips it.
    /// </summary>
    static class TestWorld
    {
        /// <summary>World + SimulationSystemGroup, NetworkTime seeded to <paramref name="tick"/>, TimeData = 1/60.
        /// <paramref name="server"/> sets WorldFlags.GameServer (the IsServer() gate some systems read).</summary>
        public static (World world, SimulationSystemGroup group) Make(string name = "TestWorld", uint tick = 1, bool server = false)
        {
            var world = server ? new World(name, WorldFlags.Game | WorldFlags.GameServer) : new World(name);
            var group = world.GetOrCreateSystemManaged<SimulationSystemGroup>();
            world.SetTime(new TimeData(elapsedTime: 0f, deltaTime: 1f / 60f));
            SetTick(world, tick);
            return (world, group);
        }

        /// <summary>As <see cref="Make"/>, plus registers ONE ISystem and sorts. Drop-in for the per-file MakeWorld&lt;T&gt;.</summary>
        public static (World world, SimulationSystemGroup group) Make<T>(string name = "TestWorld", uint tick = 1, bool server = false)
            where T : unmanaged, ISystem
        {
            var (world, group) = Make(name, tick, server);
            group.AddSystemToUpdateList(world.GetOrCreateSystem<T>());
            group.SortSystems();
            return (world, group);
        }

        /// <summary>Register an extra ISystem and re-sort (idempotent — final order is what matters).</summary>
        public static void Add<T>(World world, SimulationSystemGroup group) where T : unmanaged, ISystem
        {
            group.AddSystemToUpdateList(world.GetOrCreateSystem<T>());
            group.SortSystems();
        }

        /// <summary>The reconciled tick API: create NetworkTime if absent, else set it (a strict superset of both
        /// hand-rolled variants — behaves like GetSingletonEntity() when present, and tolerates absence).</summary>
        public static void SetTick(World world, uint tick)
        {
            var em = world.EntityManager;
            using var q = em.CreateEntityQuery(typeof(NetworkTime));
            Entity e = q.IsEmpty ? em.CreateEntity(typeof(NetworkTime)) : q.GetSingletonEntity();
            em.SetComponentData(e, new NetworkTime { ServerTick = new NetworkTick(tick) });
        }

        // ---- domain builders (only for shapes that match exactly; per-file builders with extra components stay local) ----

        public static Entity Player(EntityManager em, int netId = 1, byte region = RegionId.Base, float3 pos = default)
        {
            var e = em.CreateEntity(typeof(PlayerTag), typeof(GhostOwner), typeof(RegionTag), typeof(LocalTransform));
            em.SetComponentData(e, new GhostOwner { NetworkId = netId });
            em.SetComponentData(e, new RegionTag { Region = region });
            em.SetComponentData(e, LocalTransform.FromPosition(pos));
            return e;
        }

        public static Entity Enemy(EntityManager em, float3 pos, float hp = 50f, byte region = RegionId.Base)
        {
            var e = em.CreateEntity(typeof(EnemyTag), typeof(LocalTransform), typeof(RegionTag), typeof(Health));
            em.SetComponentData(e, LocalTransform.FromPosition(pos));
            em.SetComponentData(e, new RegionTag { Region = region });
            em.SetComponentData(e, new Health { Current = hp, Max = hp });
            return e;
        }
    }
}