using System.Linq;
using NUnit.Framework;
using UnityEngine;
using Vanguard.Board3D;

namespace Vanguard.Tests
{
    public sealed class PlaymatLayoutTests
    {
        [Test]
        public void Default_Playmat_Has_Six_Circles_Per_Side()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            for (var seat = 0; seat < 2; seat++)
            {
                var positions = Enumerable.Range(-1, PlaymatLayout.RearGuardCount + 1)
                    .Select(slot => layout.CirclePosition(seat, slot))
                    .ToList();

                Assert.AreEqual(6, positions.Count);
                Assert.AreEqual(6, positions.Select(position => position.ToString()).Distinct().Count());
            }
        }

        [Test]
        public void Vanguard_Is_Center_Front_And_Rear_Center_Exists()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            var vanguard = layout.CirclePosition(0, PlaymatLayout.VanguardSlot);
            var rearCenter = layout.CirclePosition(0, 1);
            var leftFront = layout.CirclePosition(0, 3);
            var rightFront = layout.CirclePosition(0, 4);

            Assert.AreEqual(0f, vanguard.x, 0.0001f);
            Assert.AreEqual(-config.frontRowZ, vanguard.z, 0.0001f);
            Assert.AreEqual(0f, rearCenter.x, 0.0001f);
            Assert.AreEqual(-config.backRowZ, rearCenter.z, 0.0001f);
            Assert.Less(leftFront.x, 0f);
            Assert.Greater(rightFront.x, 0f);
            Assert.AreEqual(vanguard.z, leftFront.z, 0.0001f);
            Assert.AreEqual(vanguard.z, rightFront.z, 0.0001f);
        }

        [Test]
        public void Opponent_Half_Is_Mirrored()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            for (var slot = PlaymatLayout.VanguardSlot; slot < PlaymatLayout.RearGuardCount; slot++)
            {
                var self = layout.CirclePosition(0, slot);
                var opponent = layout.CirclePosition(1, slot);
                Assert.AreEqual(-self.x, opponent.x, 0.0001f);
                Assert.AreEqual(-self.z, opponent.z, 0.0001f);
                Assert.AreEqual(self.y, opponent.y, 0.0001f);
            }
        }

        [Test]
        public void Damage_And_Hand_Do_Not_Overlap_Field()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            var damage = Enumerable.Range(0, PlaymatLayout.DamageSlots)
                .Select(index => layout.DamagePosition(0, index))
                .ToList();
            Assert.AreEqual(PlaymatLayout.DamageSlots,
                damage.Select(position => position.ToString()).Distinct().Count());

            var hand = Enumerable.Range(0, 5)
                .Select(index => layout.GetHandPose(index, 5).Position)
                .ToList();
            Assert.AreEqual(5, hand.Select(position => position.ToString()).Distinct().Count());
            Assert.IsTrue(hand.All(position => position.z < -4f));
        }

        [Test]
        public void Deck_Is_Closer_Than_Drop_After_Swap()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            var deck = layout.DeckPosition(0);
            var drop = layout.DropPosition(0);
            Assert.Greater(deck.z, drop.z);

            var opponentDeck = layout.DeckPosition(1);
            var opponentDrop = layout.DropPosition(1);
            Assert.Less(opponentDeck.z, opponentDrop.z);
        }

        [Test]
        public void Drop_Target_Finds_Own_And_Opponent_Circles()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            var nearPoint = layout.CirclePosition(0, 3);
            Assert.IsTrue(layout.TryFindDropTarget(nearPoint, selfPlayer: 1, out var near));
            Assert.AreEqual(BoardZone.RearGuard, near.Zone);
            Assert.AreEqual(3, near.Slot);
            Assert.AreEqual(1, near.Player);

            var farPoint = layout.CirclePosition(1, -1);
            Assert.IsTrue(layout.TryFindDropTarget(farPoint, selfPlayer: 1, out var far));
            Assert.AreEqual(BoardZone.Vanguard, far.Zone);
            Assert.AreEqual(-1, far.Slot);
            Assert.AreEqual(0, far.Player);
        }

        [Test]
        public void Drop_Target_Recognizes_Shared_Guardian_Zone()
        {
            var config = PlaymatLayoutConfig.CreateDefault();
            var layout = new PlaymatLayout(config);

            Assert.IsTrue(layout.TryFindDropTarget(
                new Vector3(0f, 0f, -0.45f),
                selfPlayer: 0,
                out var target));
            Assert.AreEqual(BoardZone.Guardian, target.Zone);
            Assert.AreEqual(0, target.Player);

            Assert.IsFalse(layout.TryFindDropTarget(
                new Vector3(0f, 0f, -7f),
                selfPlayer: 0,
                out _));
        }

        [Test]
        public void Move_Is_Limited_To_Own_Column()
        {
            Assert.IsTrue(BoardPlacementRules.CanMove(0, 3));
            Assert.IsTrue(BoardPlacementRules.CanMove(3, 0));
            Assert.IsTrue(BoardPlacementRules.CanMove(2, 4));
            Assert.IsTrue(BoardPlacementRules.CanMove(4, 2));
            Assert.IsFalse(BoardPlacementRules.CanMove(1, 0));
            Assert.IsFalse(BoardPlacementRules.CanMove(0, 1));
            Assert.IsFalse(BoardPlacementRules.CanMove(3, 4));
            Assert.IsFalse(BoardPlacementRules.CanMove(0, 0));
        }

        [Test]
        public void Call_Ride_And_Guard_Follow_Classic_Circles()
        {
            Assert.IsTrue(BoardPlacementRules.CanCall(0, occupied: false));
            Assert.IsTrue(BoardPlacementRules.CanCall(4, occupied: false));
            Assert.IsFalse(BoardPlacementRules.CanCall(0, occupied: true));
            Assert.IsFalse(BoardPlacementRules.CanCall(5, occupied: false));

            Assert.IsTrue(BoardPlacementRules.CanRide(BoardZone.Vanguard, -1));
            Assert.IsFalse(BoardPlacementRules.CanRide(BoardZone.RearGuard, 0));
            Assert.IsTrue(BoardPlacementRules.CanGuard(BoardZone.Guardian));
            Assert.IsFalse(BoardPlacementRules.CanGuard(BoardZone.Damage));
        }

        [Test]
        public void Call_Ride_Enter_Stand_And_Move_Preserves_State()
        {
            Assert.AreEqual(
                CardState3D.FaceUpStand,
                BoardPlacementRules.EnterFromHand(CircleAttribute.Vanguard));
            Assert.AreEqual(
                CardState3D.FaceUpStand,
                BoardPlacementRules.EnterFromHand(CircleAttribute.RearGuard));

            var rested = CardState3D.FaceUpRest;
            Assert.AreEqual(rested, BoardPlacementRules.PreserveOnMove(rested));
            Assert.IsTrue(BoardPlacementRules.PreserveOnMove(rested).Rested);
            Assert.IsTrue(BoardPlacementRules.PreserveOnMove(rested).FaceUp);
        }
    }
}