using System.Collections;
using System.Reflection;

using UnityEditor;

namespace Ubisoft
{
    /// <summary>
    /// Class containing a collection of UnityEditor related utilities.
    /// </summary>
    public class HtUnityEditorUtility : Editor
    {
        /// <summary>
        /// Gets the object the property represents, typically to be used in a <c>PropertyDrawer</c>.
        /// Taken from https://github.com/lordofduct/spacepuppy-unity-framework/blob/master/SpacepuppyBaseEditor/EditorHelper.cs.
        /// </summary>
        /// <param name="prop"><c>SerializedProperty</c> to retrieve the object from.</param>
        /// <returns>Object that the property represents.</returns>
        public static object GetTargetObjectOfProperty(SerializedProperty prop)
        {
            if (prop == null)
            {
                return null;
            }

            var path = prop.propertyPath.Replace(".Array.data[", "[");
            object obj = prop.serializedObject.targetObject;
            var elements = path.Split('.');
            foreach (var element in elements)
            {
                if (element.Contains("["))
                {
                    var elementName = element.Substring(0, element.IndexOf("["));
                    var index = System.Convert.ToInt32(element.Substring(element.IndexOf("[")).Replace("[", "").Replace("]", ""));
                    obj = GetValue_Imp(obj, elementName, index);
                }
                else
                {
                    obj = GetValue_Imp(obj, element);
                }
            }
            return obj;
        }

        private static object GetValue_Imp(object source, string name)
        {
            if (source == null)
            {
                return null;
            }

            var type = source.GetType();

            while (type != null)
            {
                var f = type.GetField(name, BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance);
                if (f != null)
                {
                    return f.GetValue(source);
                }

                var p = type.GetProperty(name, BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase);
                if (p != null)
                {
                    return p.GetValue(source, null);
                }

                type = type.BaseType;
            }

            return null;
        }

        private static object GetValue_Imp(object source, string name, int index)
        {
#pragma warning disable IDE0019 // Use pattern matching
            IEnumerable enumerable = GetValue_Imp(source, name) as IEnumerable;
#pragma warning restore IDE0019 // Use pattern matching
            if (enumerable == null)
            {
                return null;
            }

            IEnumerator enm = enumerable.GetEnumerator();
            //while (index-- >= 0)
            //    enm.MoveNext();
            //return enm.Current;

            for (int i = 0; i <= index; i++)
            {
                if (!enm.MoveNext())
                {
                    return null;
                }
            }

            return enm.Current;
        }
    }
}