using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace IoTIntegrationPlatform.Common
{
    /// <summary>
    /// 枚举对象操作
    /// </summary>
    public static class EnumExtension
    {
        /// <summary>
        /// 获取枚举的描述信息
        /// </summary>
        public static string GetDescription(this Enum em)
        {
            Type type = em.GetType();
            FieldInfo fd = type.GetField(em.ToString());
            if (fd == null)
            {
                return string.Empty;
            }
            object[] attrs = fd.GetCustomAttributes(typeof(DescriptionAttribute), false);
            string name = string.Empty;
            foreach (DescriptionAttribute attr in attrs)
            {
                name = attr.Description;
            }
            return name;
        }

        /// <summary>
        /// 获取枚举值描述
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        public static string GetEnumDescription(this Enum value)
        {
            FieldInfo fi = value.GetType().GetField(value.ToString());
            DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
            if (attributes != null && attributes.Length > 0)
            {
                return attributes[0].Description;
            }
            else
            {
                return value.ToString();
            }
        }

        ///// <summary>
        ///// 获取枚举值描述(无作用)
        ///// </summary>
        ///// <typeparam name="TEnum"></typeparam>
        ///// <param name="value"></param>
        ///// <returns></returns>
        //public static string GetDescription<TEnum>(this TEnum value) where TEnum : struct
        //{
        //    return value.ToString(); // 默认返回枚举值的名称，这通常是最好的情况。如果枚举值没有自定义描述属性，将返回名称。  
        //}

        /// <summary>
        /// 根据值获取枚举方法
        /// </summary>
        /// <param name="enumType"></param>
        /// <param name="value"></param>
        /// <returns></returns>
        public static Enum GetEnumByValue(Type enumType, string value)
        {
            return Enum.Parse(enumType, value) as Enum;
        }

        /// <summary>
        /// 获取枚举列表
        /// </summary>
        /// <param name="type"></param>
        /// <returns></returns>
        public static List<KeyValuePair<string, int>> GetEnumArray(this Type type)
        {
            var result = new List<KeyValuePair<string, int>>();
            if (type.IsEnum)
            {
                var values = Enum.GetValues(type);
                foreach (var item in values)
                {
                    result.Add(new KeyValuePair<string, int>(((Enum)item).GetDescription(), (int)item));
                }
            }
            return result;
        }

        public static List<KeyValuePair<string, int>> GetEnumArray(this Type type, params Enum[] notinValue)
        {
            var result = new List<KeyValuePair<string, int>>();
            if (type.IsEnum)
            {
                var values = Enum.GetValues(type);
                foreach (var item in values)
                {
                    if (notinValue.Contains((Enum)item))
                    {
                        continue;
                    }
                    result.Add(new KeyValuePair<string, int>(((Enum)item).GetDescription(), (int)item));
                }
            }
            return result;
        }
    }
}