using System;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;

namespace Infrastructure.Extensions
{
    public static class ExpressionExtensions
    {
        public static string GetPropertyName(this Expression<Func<object, object>> expression)
        {
            if (expression is null)
            {
                throw new ArgumentNullException(nameof(expression));
            }
            return (expression.Body as MemberExpression).Member.Name;
        }

        //public static string MemberName<T, V>(this Expression<Func<T, V>> expression)
        //{
        //    var memberExpression = expression.Body as MemberExpression;
        //    if (memberExpression == null)
        //        throw new InvalidOperationException("Expression must be a member expression");

        //    return memberExpression.Member.Name;
        //}

        //public static T GetAttribute<T>(this ICustomAttributeProvider provider)
        //    where T : Attribute
        //{
        //    var attributes = provider.GetCustomAttributes(typeof(T), true);
        //    return attributes.Length > 0 ? attributes[0] as T : null;
        //}

        public static string GetDisplayAttributeValue<T>(this Expression<Func<T, object>> expression)
        {
            if (expression is null)
            {
                throw new ArgumentNullException(nameof(expression));
            }
            var memberExpression = expression.Body as MemberExpression;

            var displayAttribute = memberExpression.Member.GetCustomAttributes().FirstOrDefault(o => o.GetType() == typeof(DisplayAttribute));
            return displayAttribute == null ? memberExpression.Member.Name : ((DisplayAttribute)displayAttribute).Name;
        }
    }
}