using NUnit.Framework;
using ProjectM.Server;
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 tests for the harvest -&gt; PERSONAL inventory reroute in
    /// <see cref="ResourceHarvestSystem"/>. A bare world is seeded with a ResourceLedger singleton, a node,
    /// a player (GhostOwner + InventorySlot + PlayerTag) and an OWNED projectile (matching GhostOwner). Pins:
    /// an owned hit lands in the player's inventory and leaves the ledger untouched; a full bag spills the
    /// remainder to the ledger; an owned projectile whose NetworkId has no live player falls back to the ledger.
    /// The 8 owner-less tests in <see cref="ResourceHarvestSystemTests"/> pin the un-owned -&gt; ledger fallback.
    /// </summary>
    public class InventoryHarvestTests
    {
        static (World world, SimulationSystemGroup group, Entity ledger) MakeWorld(string name)
        {
            var world = new World(name);
            var group = world.GetOrCreateSystemManaged<SimulationSystemGroup>();
            group.AddSystemToUpdateList(world.GetOrCreateSystem<ResourceHarvestSystem>());
            group.SortSystems();
            world.SetTime(new TimeData(elapsedTime: 0f, deltaTime: 1f / 60f));
            var em = world.EntityManager;
            var ledger = em.CreateEntity(typeof(ResourceLedger));
            em.AddBuffer<StorageEntry>(ledger);
            return (world, group, ledger);
        }

        static Entity MakeNode(EntityManager em, float3 pos, float hitRadius, byte resourceId, int remaining, float perHit)
        {
            var e = em.CreateEntity();
            em.AddComponentData(e, LocalTransform.FromPosition(pos));
            em.AddComponentData(e, new HitRadius { Value = hitRadius });
            em.AddComponentData(e, new ResourceNode { ResourceId = resourceId, Remaining = remaining, HarvestPerHit = perHit });
            return e;
        }

        static Entity MakePlayer(EntityManager em, int networkId)
        {
            var e = em.CreateEntity();
            em.AddComponentData(e, new GhostOwner { NetworkId = networkId });
            em.AddComponent<PlayerTag>(e);
            em.AddBuffer<InventorySlot>(e);
            return e;
        }

        static Entity MakeOwnedProjectile(EntityManager em, float3 pos, float2 dir, float lastStep, int networkId)
        {
            var e = em.CreateEntity();
            em.AddComponentData(e, LocalTransform.FromPosition(pos));
            em.AddComponentData(e, new Projectile { Direction = dir, LastStep = lastStep });
            em.AddComponentData(e, new GhostOwner { NetworkId = networkId });
            return e;
        }

        static int LedgerCount(EntityManager em, Entity ledger, ushort itemId)
        {
            var buf = em.GetBuffer<StorageEntry>(ledger);
            for (int i = 0; i < buf.Length; i++)
                if (buf[i].ItemId == itemId) return buf[i].Count;
            return 0;
        }

        static int InvCount(EntityManager em, Entity player, ushort itemId)
        {
            var buf = em.GetBuffer<InventorySlot>(player);
            return InventoryMath.CountOf(buf, itemId);
        }

        [Test]
        public void Owned_Harvest_Lands_In_Player_Inventory_Ledger_Untouched()
        {
            var (world, group, ledger) = MakeWorld("OwnedHarvest");
            using (world)
            {
                var em = world.EntityManager;
                var player = MakePlayer(em, networkId: 1);
                var node = MakeNode(em, new float3(10, 1, 10), 1f, ResourceId.Aether, remaining: 100, perHit: 25f);
                var proj = MakeOwnedProjectile(em, new float3(10, 1, 10), new float2(1, 0), 5f, networkId: 1);

                group.Update();

                Assert.AreEqual(25, InvCount(em, player, ResourceId.Aether), "The owner's harvest lands in their personal inventory.");
                Assert.AreEqual(0, LedgerCount(em, ledger, ResourceId.Aether), "The shared ledger is untouched by an owned harvest.");
                Assert.AreEqual(75, em.GetComponentData<ResourceNode>(node).Remaining);
                Assert.IsFalse(em.Exists(proj), "The projectile is consumed.");
            }
        }

        [Test]
        public void Full_Bag_Spills_Remainder_To_Ledger()
        {
            var (world, group, ledger) = MakeWorld("FullBagSpill");
            using (world)
            {
                var em = world.EntityManager;
                var player = MakePlayer(em, networkId: 1);
                // Fill all InventoryMaxSlots with distinct dummy items so no slot is free for the harvested id.
                var bag = em.GetBuffer<InventorySlot>(player);
                for (int i = 0; i < Tuning.InventoryMaxSlots; i++)
                    bag.Add(new InventorySlot { ItemId = (ushort)(100 + i), Count = 1 });

                var node = MakeNode(em, new float3(10, 1, 10), 1f, ResourceId.Ore, remaining: 100, perHit: 25f);
                var proj = MakeOwnedProjectile(em, new float3(10, 1, 10), new float2(1, 0), 5f, networkId: 1);

                group.Update();

                Assert.AreEqual(0, InvCount(em, player, ResourceId.Ore), "A full bag cannot take the harvested item.");
                Assert.AreEqual(25, LedgerCount(em, ledger, ResourceId.Ore), "The full amount spills to the shared ledger.");
                Assert.AreEqual(75, em.GetComponentData<ResourceNode>(node).Remaining, "The node decrements by the FULL amount, not just the part that fit.");
                Assert.IsFalse(em.Exists(proj));
            }
        }

        [Test]
        public void Owned_Projectile_With_No_Matching_Player_Falls_Back_To_Ledger()
        {
            var (world, group, ledger) = MakeWorld("NoMatchingPlayer");
            using (world)
            {
                var em = world.EntityManager;
                var player = MakePlayer(em, networkId: 1);
                var node = MakeNode(em, new float3(10, 1, 10), 1f, ResourceId.Aether, remaining: 100, perHit: 25f);
                // Projectile owned by NetworkId 99 — no live player has that id.
                var proj = MakeOwnedProjectile(em, new float3(10, 1, 10), new float2(1, 0), 5f, networkId: 99);

                group.Update();

                Assert.AreEqual(0, InvCount(em, player, ResourceId.Aether), "Player 1 gets nothing — it didn't fire this shot.");
                Assert.AreEqual(25, LedgerCount(em, ledger, ResourceId.Aether), "An unresolvable owner falls back to the shared ledger.");
                Assert.IsFalse(em.Exists(proj));
            }
        }
    }
}