using System.Collections.Generic;
using System.Runtime.CompilerServices;
using CoreGame;
using UnityEngine;

namespace CoreGame.Render
{
    public static class ColliderSrv
    {
        private static readonly Dictionary<Collider2D, int> s_ColliderMap = new Dictionary<Collider2D, int>();

        private static readonly int s_PlayerLayer = LayerMask.NameToLayer("Player");
        private static readonly int s_EnemyLayer = LayerMask.NameToLayer("Enemy");
        public static readonly int s_ObstacleLayer = LayerMask.NameToLayer("Obstacle");

        private static int[] s_PlayerCollisionMasks;
        private static int[] s_EnemyCollisionMasks;

        public static void Init()
        {
            s_ColliderMap.Clear();
            InitCollisionMasks();
        }

        private static void InitCollisionMasks()
        {
            const int maxConditions = 1 << 3; //2^3 三种碰撞条件，敌方，友方，障碍物，可能会添加
            s_PlayerCollisionMasks = new int[maxConditions];
            s_EnemyCollisionMasks = new int[maxConditions];

            for (var i = 0; i < maxConditions; i++)
            {
                s_PlayerCollisionMasks[i] = CalculateLayerMask(s_PlayerLayer, s_EnemyLayer, i);
                s_EnemyCollisionMasks[i] = CalculateLayerMask(s_EnemyLayer, s_PlayerLayer, i);
            }
        }


        private static int CalculateLayerMask(int sameLayer, int oppositeLayer, int collideWith)
        {
            var mask = 0;
            var sameLayerMask = 1 << sameLayer;
            var oppositeLayerMask = 1 << oppositeLayer;
            var obstacleLayerMask = 1 << s_ObstacleLayer;
            if ((collideWith & 1) != 0) // 敌方
                mask |= oppositeLayerMask;
            if ((collideWith & 2) != 0) // 友方
                mask |= sameLayerMask;
            if ((collideWith & 4) != 0) // 建筑物
                mask |= obstacleLayerMask;
            return mask == 0 ? LayerMask.GetMask("Default") : mask;
        }


        /// <summary>
        /// 碰撞LayerMask
        /// </summary>
        /// <param name="faction">自己所在阵营</param>
        /// <param name="collideWith">碰撞参数掩码，1-敌方，2-友方，4-建筑物</param>
        /// <returns></returns>
        public static LayerMask GetLayerMask(Faction faction, int collideWith)
        {
            return faction switch
            {
                Faction.Player => s_PlayerCollisionMasks[collideWith],
                Faction.Enemy => s_EnemyCollisionMasks[collideWith],
                _ => LayerMask.GetMask("Default")
            };
        }

        public static int GetLayer(Faction faction)
        {
            if (faction == Faction.Player)
                return s_PlayerLayer;
            if (faction == Faction.Enemy)
                return s_EnemyLayer;
            return LayerMask.NameToLayer("Default");
        }

        public static void AddCollider(Collider2D collider, int eid)
        {
            if (!s_ColliderMap.TryAdd(collider, eid))
            {
                BattleLogger.LogInfo("ColliderSrv AddCollider failed");
            }
        }

        public static void RemoveCollider(Collider2D collider)
        {
            if (!s_ColliderMap.Remove(collider))
            {
                BattleLogger.LogInfo("ColliderSrv RemoveCollider failed");
            }
        }

        public static void DisableCollider(Collider2D collider)
        {
            if (!s_ColliderMap.ContainsKey(collider))
            {
                BattleLogger.LogInfo("ColliderSrv DisableCollider failed");
            }
            collider.enabled = false;
        }

        public static void EnableCollider(Collider2D collider)
        {
            if (!s_ColliderMap.ContainsKey(collider))
            {
                BattleLogger.LogInfo("ColliderSrv EnableCollider failed");
            }
            collider.enabled = true;
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static CombatEntity GetEntityByCollider(Collider2D collider)
        {
            if (s_ColliderMap.TryGetValue(collider, out int eid))
            {
                return (CombatEntity)Contexts.Combat.GetEntity(eid);
            }
            return null;
        }
    }
}