using System;
using System.Collections.Generic;
using System.Linq;
using Sirenix.OdinInspector;
using UnityEngine;

// ReSharper disable once CheckNamespace
namespace BlueWaterProject
{
    [Serializable]
    public class UnitMatrix
    {
        public int soldiers;    // 부대 안의 병사 수
        public int rows;        // 배치될 행의 갯수
        public int columns;     // 배치될 열의 갯수
        //public int centerNum;   // 부대의 중심 번호
        
        public UnitMatrix(int soldiers, int rows, int columns)
        {
            this.soldiers = soldiers;
            this.rows = rows;
            this.columns = columns;
        }
    }
    
    public class UnitManager : Singleton<UnitManager>
    {
        #region Property and variable

        [Tooltip("바닥 레이어")]
        [field: SerializeField] public LayerMask GroundLayer { get; private set; }
        
        [Tooltip("바닥과의 최대 허용 거리")]
        [field: SerializeField] public float MaxGroundDistance { get; private set; } = 0.5f;
        
        [Tooltip("병력 간의 간격")]
        [field: SerializeField] public float SoldierSpacing { get; private set; } = 0.5f;
        
        [Tooltip("부대 배치 행렬")]
        [field: SerializeField] public List<UnitMatrix> UnitMatrices { get; private set; } = new(MATRICES_CAPACITY);
        
        [Tooltip("병력들의 프리팹 리스트(순서 중요)")]
        [SerializeField] private List<GameObject> soldierPrefabList = new(SOLDIER_PREFAB_CAPACITY);

        [Tooltip("플레이어가 가지고 있는 부대리스트")]
        [SerializeField] private List<UnitController> playerUnitList = new(PLAYER_UNIT_CAPACITY);
        
        public IReadOnlyList<UnitController> PlayerUnitList => playerUnitList;
        
        private Transform playerUnits;

        private const int MATRICES_CAPACITY = 9;
        private const int SOLDIER_PREFAB_CAPACITY = 10;
        private const int PLAYER_UNIT_CAPACITY = 50;

        #endregion

        #region Unity built-in function

        protected override void OnAwake()
        {
            GroundLayer = LayerMask.GetMask("Ground");
            InitUnitMatrices();
            InitPlayerUnitList();
        }

        private void Reset()
        {
            GroundLayer = LayerMask.GetMask("Ground");
            MaxGroundDistance = 0.5f;
            SoldierSpacing = 0.5f;
            soldierPrefabList = new List<GameObject>(SOLDIER_PREFAB_CAPACITY);   // TODO : 프리팹 자동 리셋화 필요
            InitUnitMatrices();
            InitSoldierPrefabList();
            InitPlayerUnitList();
        }

        #endregion

        #region Custom function

        /// <summary>
        /// 부대 배치 행렬 초기화 함수
        /// </summary>
        [GUIColor(0, 1, 0)]
        [ShowIf("@UnitMatrices.Count != MATRICES_CAPACITY")]
        [Button("행렬 초기화")]
        private void InitUnitMatrices()
        {
            UnitMatrices = new List<UnitMatrix>(MATRICES_CAPACITY)
            {
                new(1, 1, 1),
                new(2, 1, 2),
                new(3, 1, 3),
                new(4, 2, 2),
                new(6, 2, 3),
                new(8, 2, 4),
                new(9, 3, 3),
                new(12, 3, 4),
                new(16, 4, 4),
            };
        }
        
#if UNITY_EDITOR
        /// <summary>
        /// 프리팹 초기화 함수
        /// </summary>
        [GUIColor(0, 1, 0)]
        [ShowIf("@soldierPrefabList.Count != SOLDIER_PREFAB_CAPACITY")]
        [Button("프리팹 초기화")]
        private void InitSoldierPrefabList()
        {
            soldierPrefabList = new List<GameObject>(SOLDIER_PREFAB_CAPACITY)
            {
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Enemy", "Archer_E"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Enemy", "SpearKnight_E"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Enemy", "Spearman_E"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Enemy", "SwordKnight_E"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Enemy", "Swordman_E"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Pirate", "Archer_P"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Pirate", "Axeman_P"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Pirate", "Spearman_P"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Pirate", "SwordKnight_P"),
                Utils.LoadPrefabFromFolder("Assets/05.Prefabs/Character/Pirate", "Swordman_P")
            };
        }
#endif
        
        /// <summary>
        /// 플레이어가 가진 유닛 리스트 초기화
        /// </summary>
        [GUIColor(0, 1, 0)]
        [Button("플레이어 유닛 가져오기")]
        private void InitPlayerUnitList()
        {
            var playerUnitsObj = GameObject.Find("PlayerUnits");
            if (playerUnitsObj)
            {
                playerUnits = playerUnitsObj.transform;
            }
            else
            {
                playerUnitsObj = new GameObject("PlayerUnits");
                playerUnitsObj.transform.SetPositionAndRotation(Vector3.zero, Quaternion.identity);
                playerUnits = playerUnitsObj.transform;
            }

            playerUnitList = new List<UnitController>(PLAYER_UNIT_CAPACITY);
            
            foreach (Transform item in playerUnits)
            {
                if (!item.gameObject.activeSelf) continue;
                
                playerUnitList.Add(item.GetComponent<UnitController>());
            }
        }

        /// <summary>
        /// 부대 생성 함수
        /// </summary>
        public void CreateUnit(UnitController unitController)
        {
            DestroyDeployedSoldiers(unitController);
            
            var baseName = soldierPrefabList[(int)unitController.unit.unitType - 1].name;

            if (string.IsNullOrEmpty(unitController.unit.unitName))
            {
                const int maxIterations = 100;
                var namingNum = 0;

                while (namingNum < maxIterations)
                {
                    var newUnitName = $"{baseName}_Unit_{namingNum + 1:00}";
                    var checkGameObject = GameObject.Find(newUnitName);
                    if (checkGameObject && checkGameObject != unitController.gameObject)
                    {
                        namingNum++;
                    }
                    else
                    {
                        unitController.gameObject.name = newUnitName;
                        break;
                    }
                }
            }
            else
            {
                unitController.gameObject.name = unitController.unit.unitName;
            }
            
            unitController.gameObject.layer = LayerMask.NameToLayer("Unit");
            unitController.unit.soldierList = new List<AiController>(unitController.unit.soliderCount);
            
            var matrix = UnitMatrices.Find(um => um.soldiers == unitController.unit.soliderCount);
            if (matrix == null)
            {
                Debug.LogError("사용할 수 없는 병력의 숫자입니다. UnitManager의 UnitMatrices를 확인해주세요.");
                return;
            }
            
            var unitControllerTransform = unitController.transform;
            var unitControllerRotation = unitControllerTransform.rotation;
            unitControllerTransform.rotation = Quaternion.identity;

            for (var i = 0; i < unitController.unit.soliderCount; i++)
            {
                var row = i / matrix.columns;
                var column = i % matrix.columns;

                var xOffset = (column - (matrix.columns - 1) / 2.0f) * SoldierSpacing;
                var zOffset = (row - (matrix.rows - 1) / 2.0f) * SoldierSpacing;
                var spawnPosition = unitControllerTransform.position + new Vector3(xOffset, 0, zOffset);

                var soldierObject = Instantiate(soldierPrefabList[(int)unitController.unit.unitType - 1], spawnPosition, 
                    Quaternion.identity, unitController.transform).GetComponent<AiController>();

                var newSoldierName = $"{baseName}_{i + 1:00}";

                soldierObject.name = newSoldierName;
                unitController.unit.soldierList.Add(soldierObject);
                soldierObject.gameObject.SetActive(false);
            }
            unitController.transform.rotation *= unitControllerRotation;
            
            if (unitController.unit.unitType.ToString().Contains("_E"))
            {
                unitController.SetAttackerType(AttackerType.DEFENSE);
                foreach (var soldier in unitController.unit.soldierList)
                {
                    soldier.SetAttackerType(AttackerType.DEFENSE);
                }
            }
            else if (unitController.unit.unitType.ToString().Contains("_P"))
            {
                unitController.SetAttackerType(AttackerType.OFFENSE);
                foreach (var soldier in unitController.unit.soldierList)
                {
                    soldier.SetAttackerType(AttackerType.DEFENSE);
                }
            }
        }
        
        /// <summary>
        /// 유닛 배치 함수
        /// </summary>
        public bool CanAssignUnit(UnitController unitController, Vector3 assignPos)
        {
            if (unitController.unit.soldierList.Count <= 0) return false;
            
            unitController.transform.position = assignPos;

            for (var i = 0; i < unitController.unit.soliderCount; i++)
            {
                var soldierPos = unitController.unit.soldierList[i].transform.position;
                var ray = new Ray(soldierPos, Vector3.down);
                if (Physics.Raycast(ray, out var hit, MaxGroundDistance, GroundLayer))
                {
                    soldierPos.y = hit.point.y;
                }
                else
                {
                    return false;
                }
            }

            return true;
        }

        public void AssignUnit(UnitController unitController, Vector3 assignPos)
        {
            unitController.transform.position = assignPos;
            foreach (var item in unitController.unit.soldierList)
            {
                item.gameObject.SetActive(true);
            }
        }

        /// <summary>
        /// 기존에 생성된 부대 병력들이 있으면 확인해서 삭제해주는 함수
        /// </summary>
        private void DestroyDeployedSoldiers(UnitController unitController)
        {
            if (unitController.transform.childCount <= 0) return;
            
            for (var i = unitController.transform.childCount - 1; i >= 0; i--)
            {
                if (Application.isPlaying)
                {
                    Destroy(unitController.transform.GetChild(i).gameObject);
                }
                else
                {
                    DestroyImmediate(unitController.transform.GetChild(i).gameObject);
                }
            }
        }

        /// <summary>
        /// playerUnitList 내의 속성
        /// </summary>
        public void RemovePlayerUnitListElement(UnitController unitController)
        {
            if (playerUnitList.Contains(unitController))
            {
                playerUnitList.Remove(unitController);
            }
            else
            {
                Debug.Log("제거하려는 속성이 리스트 내에 존재하지 않습니다.");
            }
        }

        #endregion
    }
}