using Microsoft.AspNetCore.Html;
using System.Collections;

namespace YLErp.Web
{
    public static class HtmlExtensions
    {
        /// <summary>
        /// 序列化对象到htmlstring，处理了对象为null时的情况
        /// </summary>
        public static IHtmlContent JsonSerialize<T>(this IHtmlHelper helper, T value, bool ignoreNullValue = true, bool camelCase = false)
        {
            if (value == null)
            {
                var type = typeof(T);
                var untype = Nullable.GetUnderlyingType(type);
                if (untype != null)
                {
                    type = untype;
                }
                if (type.IsValueType)
                {
                    var val = Activator.CreateInstance(type);
                    return new HtmlString(JsonHelper.ToJson(val));
                }
                if (type.IsArray || typeof(IEnumerable).IsAssignableFrom(type))
                {
                    return new HtmlString("[]");
                }
                return new HtmlString("{}");
            }

            return new HtmlString(JsonHelper.ToJson(value, ignoreNullValue, camelCase));
        }

        /// <summary>
        /// 
        /// </summary>
        public static SelectListItem AsSelectListItem(this SelectItem selectItem)
        {
            return selectItem != null ? new SelectListItem
            {
                Disabled = selectItem.Disabled,
                Selected = selectItem.Selected,
                Text = selectItem.Text,
                Value = selectItem.Value
            } : null;
        }

        /// <summary>
        /// 
        /// </summary>
        public static List<SelectListItem> AsSelectListItems(this IEnumerable<SelectItem> selectItems)
        {
            return selectItems?.Select(n => new SelectListItem
            {
                Disabled = n.Disabled,
                Selected = n.Selected,
                Text = n.Text,
                Value = n.Value
            }).ToList();
        }
    }
}