using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using Cielonos.MainGame.Characters;
using Sirenix.OdinInspector;
using SLSUtilities.FunctionalAnimation;
using UnityEngine;

namespace Cielonos.MainGame
{
    public partial class CombatManager
    {
        public partial class EnemySubmodule : SubmoduleBase<CombatManager>
        {
            public enum SortingType
            {
                Nearest,
                Farthest
            }

            private readonly List<Enemy> _activeEnemiesList;
            private readonly ReadOnlyCollection<Enemy> _activeEnemies;

            public IReadOnlyList<Enemy> ActiveEnemies => _activeEnemies;
            public int ActiveEnemyCount => _activeEnemiesList.Count;
            private int TargetingVersion { get; set; }

            /// <summary>
            /// 敌人从活跃列表中移除时触发（即敌人死亡/离场）。
            /// 参数为被移除的敌人实例。
            /// </summary>
            public event Action<Enemy> OnEnemyRemoved;

            public EnemySubmodule(CombatManager owner) : base(owner)
            {
                _activeEnemiesList = new List<Enemy>();
                _activeEnemies = _activeEnemiesList.AsReadOnly();
            }

            /// <summary>
            /// 将敌人加入活跃列表。所有敌人注册都应经过这里，避免外部直接修改索敌源。
            /// </summary>
            public void RegisterEnemy(Enemy enemy)
            {
                if (enemy == null || _activeEnemiesList.Contains(enemy)) return;

                _activeEnemiesList.Add(enemy);
                TargetingVersion++;
            }

            /// <summary>
            /// 将敌人从活跃列表中移除并触发 OnEnemyRemoved 事件。
            /// 由 Automata.Die() 调用，替代直接操作活跃敌人列表。
            /// </summary>
            public void RemoveEnemy(Enemy enemy)
            {
                if (!_activeEnemiesList.Remove(enemy)) return;

                TargetingVersion++;
                OnEnemyRemoved?.Invoke(enemy);
            }

            /// <summary>
            /// 清空活跃敌人列表（房间重置时调用）。不触发逐条 OnEnemyRemoved 事件。
            /// </summary>
            public void Reset()
            {
                if (_activeEnemiesList.Count == 0) return;

                _activeEnemiesList.Clear();
                TargetingVersion++;
            }
            
            private List<Enemy> CollectEnemiesInRadius(Vector3 origin, float radius, SortingType sortingType = SortingType.Nearest)
            {
                List<Enemy> enemiesInRadius = new List<Enemy>();
                foreach (Enemy enemy in _activeEnemiesList)
                {
                    if (IsEnemyInRadius(enemy, origin, radius))
                    {
                        enemiesInRadius.Add(enemy);
                    }
                }

                if (sortingType == SortingType.Nearest)
                {
                    enemiesInRadius.Sort((a, b) =>
                        GetSurfaceDistance(origin, a).CompareTo(GetSurfaceDistance(origin, b)));
                }
                else if (sortingType == SortingType.Farthest)
                {
                    enemiesInRadius.Sort((a, b) =>
                        GetSurfaceDistance(origin, b).CompareTo(GetSurfaceDistance(origin, a)));
                }

                return enemiesInRadius;
            }

            public bool IsEnemyInRadius(Enemy enemy, Vector3 origin, float radius)
            {
                if (enemy == null || enemy.statusSm.isDead) return false;

                return GetSurfaceDistance(origin, enemy) <= radius;
            }

            [Button("Debug: Force GetHit All Enemies", ButtonSizes.Medium)]
            [GUIColor(1f, 0.55f, 0.35f)]
            private void DebugForceGetHitAllEnemies()
            {
                for (int i = 0; i < _activeEnemiesList.Count; i++)
                {
                    Enemy enemy = _activeEnemiesList[i];
                    if (enemy == null || enemy.statusSm.isDead) continue;

                    Vector3 direction = Vector3.zero;
                    Player player = MainGameManager.Player;
                    if (player != null)
                    {
                        direction = enemy.transform.position - player.transform.position;
                    }

                    enemy.GetHit(
                        Breakthrough.Type.Forced,
                        out _,
                        DisruptionType.ForcedExternal,
                        direction);
                }
            }
            [Button("Debug: Force Deplete All Enemies", ButtonSizes.Medium)]
            [GUIColor(1f, 0.55f, 0.35f)]
            private void DebugForceDepleteAllEnemies()
            {
                for (int i = 0; i < _activeEnemiesList.Count; i++)
                {
                    Enemy enemy = _activeEnemiesList[i];
                    if (enemy == null || enemy.statusSm.isDead) continue;
                    Player player = MainGameManager.Player;
                    enemy.TakeDepletion(player, 999999, false);
                }
            }

            private float GetSurfaceDistance(Vector3 origin, Enemy enemy)
            {
                if (enemy == null) return float.MaxValue;

                float colliderRadius = enemy.collisionSc != null ? enemy.collisionSc.colliderRadius : 0f;
                return Mathf.Max(0f, Vector3.Distance(origin, enemy.transform.position) - colliderRadius);
            }
            
            /// <summary>
            /// 获取所有可见敌人
            /// </summary>
            public List<Enemy> GetVisibleEnemies(float radius = 50f)
            {
                return Query(radius).OnlyVisible().Candidates();
            }
            
            /// <summary>
            /// 获取按屏幕X坐标从左到右排序的可见敌人列表
            /// </summary>
            public List<Enemy> GetVisibleEnemiesSortedByScreenX(float radius = 50f)
            {
                List<Enemy> visibleEnemies = GetVisibleEnemies(radius);
                
                visibleEnemies.Sort((a, b) =>
                {
                    Vector3 screenA = MainGameManager.Player.viewSc.playerCamera.WorldToScreenPoint(a.CenterPoint.position);
                    Vector3 screenB = MainGameManager.Player.viewSc.playerCamera.WorldToScreenPoint(b.CenterPoint.position);
                    return screenA.x.CompareTo(screenB.x);
                });
                
                return visibleEnemies;
            }
        }
    }
}