using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace FiradzoAssets
{
    /// <summary>
    /// This script automatically adds and removes weapon and shield, 
    /// but works only while prefab opened for editing in prefab scene because of deleting prefab instance parts in scene is not allowed
    /// </summary>
    public class WeaponAttachmentHelper : MonoBehaviour
    {
        private const string ArmatureObjectName = "Armature";
        private const string RightHandWeaponBoneName = "weapon_end";
        private const string LeftHandShieldBone = "shield_end";

        [SerializeField]
        private Transform armatureRoot;
        [Space(10f)]
        [SerializeField]
        private Transform rightHandWeaponBone;
        [SerializeField]
        private Transform leftHandShieldBone;

        [Space(10f)]
        [SerializeField]
        private GameObject rightHandWeaponPrefab;
        [SerializeField]
        private GameObject shieldPrefab;

        private void OnValidate()
        {
            var isDirty = false;
            if (armatureRoot == null)
            {
                armatureRoot = transform.Find(ArmatureObjectName);
                if (armatureRoot != null)
                {
                    isDirty = true;
                }
            }
            if (armatureRoot != null)
            {
                if (rightHandWeaponBone == null)
                {
                    rightHandWeaponBone = FindTransfomInChildRecursive(armatureRoot, RightHandWeaponBoneName);
                    if (rightHandWeaponBone != null)
                    {
                        isDirty = true;
                    }
                }

                if (leftHandShieldBone == null)
                {
                    leftHandShieldBone = FindTransfomInChildRecursive(armatureRoot, LeftHandShieldBone);
                    if (leftHandShieldBone != null)
                    {
                        isDirty = true;
                    }
                }
            }

#if UNITY_EDITOR
            if (isDirty)
            {
                UnityEditor.EditorUtility.SetDirty(this);
            }
#endif
        }

#if UNITY_EDITOR
        public void SetWeaponAndRebind(GameObject rightHandWeaponPrefab, GameObject shieldPrefab)
        {
            this.rightHandWeaponPrefab = rightHandWeaponPrefab;
            this.shieldPrefab = shieldPrefab;
            TryRefreshBindedItems();
        }

        private bool isPerformingItemsRefreshing;
        public void TryRefreshBindedItems()
        {
            if (isPerformingItemsRefreshing)
            {
                return;
            }

            isPerformingItemsRefreshing = true;
            if (gameObject.scene.isLoaded && !UnityEditor.PrefabUtility.IsPartOfPrefabInstance(gameObject))
            {
                TryRefreshBindedItem(rightHandWeaponBone, rightHandWeaponPrefab);
                TryRefreshBindedItem(leftHandShieldBone, shieldPrefab);
            }
            isPerformingItemsRefreshing = false;
        }

        private void TryRefreshBindedItem(Transform parent, GameObject itemPrefab)
        {
            if (parent != null)
            {
                if (itemPrefab == null)
                {
                    if (parent.childCount > 0)
                    {
                        var childObject = parent.GetChild(0).gameObject;
                        DestroyObject(childObject);
                    }
                }
                else
                {
                    if (parent.childCount > 0)
                    {
                        var childObject = parent.GetChild(0).gameObject;
                        if (childObject.name != itemPrefab.name)
                        {
                            if (DestroyObject(childObject))
                            {
                                InstantiateItem(parent, itemPrefab);
                            }
                        }
                    }
                    else
                    {
                        InstantiateItem(parent, itemPrefab);
                    }
                }
            }
        }


        private bool DestroyObject(GameObject @object)
        {
            if (UnityEditor.PrefabUtility.IsPartOfPrefabInstance(@object.transform.parent))
            {
                //Debug.LogFormat("Can't destroy item <b>{0}</b> in scene because it is part of prefab instance, open prefab for editing to do so", @object);
                return false;
            }
            GameObject.DestroyImmediate(@object);
            return true;
        }

        private void InstantiateItem(Transform parent, GameObject itemPrefab)
        {
            var itemInstance = GameObject.Instantiate(itemPrefab, parent);
            itemInstance.name = itemPrefab.name;
            itemInstance.transform.localPosition = Vector3.zero;
            itemInstance.transform.localRotation = Quaternion.identity;
        }
#endif


        private Transform FindTransfomInChildRecursive(Transform transform, string transformName)
        {
            if (transform.name == transformName)
            {
                return transform;
            }
            var childCount = transform.childCount;
            if (transform.childCount > 0)
            {
                Transform result;
                for (int i = 0; i < childCount; i++)
                {
                    result = FindTransfomInChildRecursive(transform.GetChild(i), transformName);
                    if (result != null)
                    {
                        return result;
                    }
                }
            }
            return null;
        }
    }
}