using System;
using System.Collections;
using UnityEngine;
using UnityEditor;

[CustomPropertyDrawer(typeof(AutoInjector), true)]
public class AutoInjectorDrawer : PropertyDrawer
{
    AutoInjector AutoInjector => attribute as AutoInjector;

    public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
    {
        Type fieldType = fieldInfo.FieldType;

        if (!fieldType.IsSubclassOf(typeof(Component)) ||
            fieldType.IsSubclassOf(typeof(IEnumerable)) ||
            fieldType.IsArray)
        {
            return;
        }

        if (property.objectReferenceValue == null || !property.objectReferenceValue.GetType().IsSubclassOf(fieldType))
        {
            Component target = property.serializedObject.targetObject as Component;

            Transform pwd = RecursiveFind(target.transform, AutoInjector.Path.Split('/'), 0);

            if (pwd != null) 
            {
                property.objectReferenceValue = pwd.GetComponent(fieldType);
            }
            else
            {
                property.objectReferenceValue = null;
            }
        }
        var guiEnabled = GUI.enabled;
        GUI.enabled = false;
        EditorGUI.PropertyField(position, property, new GUIContent(label.text, AutoInjector.Path), true);
        GUI.enabled = guiEnabled;
    }

    Transform RecursiveFind(Transform pwd, string[] chunk, int pwdIndex)
    {
        if(pwd is null || pwdIndex >= chunk.Length) return pwd;
        return RecursiveFind(pwd.Find(chunk[pwdIndex]), chunk, pwdIndex + 1);
    }
}