using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
using System.Web.Mvc;
using Pcb.Common.Attributes;

namespace Pcb.Common
{
    /// <summary>
    /// 枚举帮助类
    /// 
    /// @2015.6.18
    /// </summary>
    public static class EnumHelper
    {
        /// <summary>
        /// 转成列表
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public static List<T> ToList<T>()
        {
            var fields = typeof(T).GetFields();
            var list = (from f in fields
                        where f.FieldType == typeof(T)
                        select (T)f.GetRawConstantValue()
                ).ToList();
            return list;
        }

        /// <summary>
        /// 返回枚举值对应的NoteAttribute注释信息        
        /// </summary>
        /// <typeparam name="T">枚举</typeparam>
        /// <param name="val">值</param>
        /// <returns>注释</returns>
        public static string GetNoteByVal<T>(object val) where T : struct
        {
            var field = typeof(T).GetFields().FirstOrDefault(x => x.FieldType == typeof(T) && x.GetRawConstantValue() == val);
            if (field == null) return string.Empty;
            var attr = field.GetCustomAttributes().FirstOrDefault(x => x.GetType() == typeof(NoteAttribute)) as NoteAttribute;
            return attr == null ? string.Empty : attr.Note;
        }

        /// <summary>
        /// 返回常量对应的NoteAttribute注释信息        
        /// </summary>
        /// <typeparam name="T">常量类</typeparam>
        /// <param name="val">值</param>
        /// <returns>注释</returns>
        public static string GetNoteByConst<T>(string val)
        {
            var field = typeof(T).GetFields().FirstOrDefault(x => x.Name == val);
            if (field == null) return string.Empty;
            var attr = field.GetCustomAttributes().FirstOrDefault(x => x.GetType() == typeof(NoteAttribute)) as NoteAttribute;
            return attr == null ? string.Empty : attr.Note;
        }

        /// <summary>
        /// 返回常量对应的NoteAttribute注释信息        
        /// </summary>
        /// <typeparam name="T">常量类</typeparam>
        /// <param name="val">值</param>
        /// <returns>注释</returns>
        public static string GetCacheTypeNote<T>(string val)
        {
            var field = typeof(T).GetFields().FirstOrDefault(x => x.Name == val);
            if (field == null) return string.Empty;
            var attr = field.GetCustomAttributes().FirstOrDefault(x => x.GetType() == typeof(CacheKeyNoteAttribute)) as CacheKeyNoteAttribute;
            return attr == null ? string.Empty : attr.Note;
        }

        /// <summary>
        /// 枚举值转int16
        /// </summary>
        /// <param name="source">枚举</param>
        /// <returns>int16(short)</returns>
        public static short ToShort(this System.Enum source)
        {
            return Convert.ToInt16(source.GetHashCode());
        }

        /// <summary>
        /// 枚举值转byte
        /// </summary>
        /// <param name="source">枚举</param>
        /// <returns>byte</returns>
        public static byte ToByte(this System.Enum source)
        {
            return Convert.ToByte(source.GetHashCode());
        }

        /// <summary>
        /// 返回枚举注释
        /// </summary>
        /// <param name="source">枚举</param>
        /// <returns>注释</returns>
        public static string ToNote(this System.Enum source)
        {
            var field = source.GetType().GetField(source.ToString());
            if (field == null) { return string.Empty; }
            var attr = field.GetCustomAttributes().FirstOrDefault(x => x.GetType() == typeof(NoteAttribute)) as NoteAttribute;
            return attr == null ? string.Empty : attr.Note;
        }

        public static Dictionary<int, string> GetNotes<TEnum>() where TEnum : struct
        {
            var notes = new Dictionary<int, string>();

            var fields = typeof(TEnum).GetFields();
            foreach (var f in fields)
            {
                if (f.FieldType == typeof(TEnum))
                {
                    var attr = f.GetCustomAttribute(typeof(NoteAttribute)) as NoteAttribute;
                    string note = null;
                    if (attr != null)
                    {
                        note = attr.Note;
                    }

                    var rawConstantValue = (int)f.GetRawConstantValue();
                    notes.Add(rawConstantValue, note);
                }

            }

            return notes;
        }

        public static string ToNote(this int val, Type T)
        {
            Type type = T;
            string name = System.Enum.GetName(type, val);
            if (name == null)
                return string.Empty;
            FieldInfo fd = type.GetField(name);
            object[] attrs = fd.GetCustomAttributes(typeof(NoteAttribute), false);
            string note = string.Empty;
            foreach (NoteAttribute attr in attrs)
            {
                note = attr.Note;
            }
            return note;
        }

        public static string ToNote(this int? val, Type T)
        {
            if (val == null) return "";
            return ToNote(val.Value, T);
        }

        /// <summary>
        /// 获取常量的属性
        /// </summary>
        /// <param name="val"></param>
        /// <param name="T"></param>
        /// <returns></returns>
        public static string ToConstNote(this string val, Type T)
        {
            Type type = T;
            var info = type.GetFields();
            if (val == null)
                return string.Empty;
            FieldInfo fd = type.GetField(val);
            object[] attrs = fd.GetCustomAttributes(typeof(NoteAttribute), false);
            string note = string.Empty;
            foreach (NoteAttribute attr in attrs)
            {
                note = attr.Note;
            }
            return note;
        }


        /// <summary>
        /// 将枚举转换成下拉列表
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public static List<SelectListItem> ToSelectListItem<T>()
        {
            List<SelectListItem> listStatus = new List<SelectListItem>();
            try
            {
                var fields = typeof(T).GetFields();

                foreach (var f in fields)
                {
                    var attr = f.CustomAttributes.Where(x => x.AttributeType.FullName == typeof(NoteAttribute).FullName).FirstOrDefault();
                    if (attr != null)
                    {
                        listStatus.Add(new SelectListItem() { Value = f.GetRawConstantValue().ToString(), Text = attr.ConstructorArguments[0].Value.ToString() });
                    }
                }
            }
            catch (Exception ex)
            {
                LogHelper.Error(ex.ToString());
            }
            return listStatus;
        }

        public static List<SelectListItem> ToSelectListItemInHasCode<T>()
        {
            List<SelectListItem> listStatus = new List<SelectListItem>();
            try
            {
                var fields = typeof(T).GetFields();

                foreach (var f in fields)
                {
                    var attr = f.CustomAttributes.Where(x => x.AttributeType.FullName == typeof(NoteAttribute).FullName).FirstOrDefault();
                    if (attr != null)
                    {
                        listStatus.Add(new SelectListItem() { Value = f.Name, Text = attr.ConstructorArguments[0].Value.ToString() });
                    }
                }
            }
            catch (Exception ex)
            {
                LogHelper.Error(ex.ToString());
            }
            return listStatus;
        }

        #region 戴雁冰扩展
        /// <summary>
        /// 获取类型的说明
        /// </summary>
        public static string _GetNoteAttr(this Type TypeObj)
        {
            var enumAttr = TypeObj.GetCustomAttributes(_NoteAttribute, true);
            if (enumAttr.Length == 0) { return string.Empty; }

            var desc = enumAttr[0] as NoteAttribute;
            return desc.Note ?? string.Empty;
        }
        /// <summary>
        /// 转成值与说明的字典
        /// </summary>
        public static Dictionary<TNumType, string> _GetValueNoteDicFromEnumType<TNumType>(this Type EnmType)
        {
            var ns = System.Enum.GetNames(EnmType);
            var vs = System.Enum.GetValues(EnmType); ;
            var dic = new Dictionary<TNumType, string>(ns.Length);
            for (int i = 0; i < ns.Length; i++)
            {
                FieldInfo finfo = EnmType.GetField(ns[i]);
                object[] enumAttr = finfo.GetCustomAttributes(_NoteAttribute, true);
                string remark = string.Empty;
                if (enumAttr.Length > 0)
                {
                    var desc = enumAttr[0] as NoteAttribute;
                    if (!string.IsNullOrEmpty(desc.Note))
                    {
                        remark = desc.Note;
                    }
                }
                dic[(TNumType)vs.GetValue(i)] = remark;
            }
            return dic;
        }
        static Type _NoteAttribute = typeof(NoteAttribute);
        /// <summary>
        /// 获取类型的说明
        /// </summary>
        public static string _GetDescriptionAttr(this Type TypeObj)
        {
            var enumAttr = TypeObj.GetCustomAttributes(_DesciptionAttribute, true);
            if (enumAttr.Length == 0) { return string.Empty; }

            var desc = enumAttr[0] as DescriptionAttribute;
            return desc.Description ?? string.Empty;
        }
        /// <summary>
        /// 获取枚举值的说明
        /// </summary>
        public static string _GetDescriptionByEnumValue<TEnum>(this TEnum EnmValue)
        {
            var EnmType = typeof(TEnum);

            FieldInfo finfo = EnmType.GetField(EnmValue.ToString());
            if (finfo == null) { return string.Empty; }

            var enumAttr = finfo.GetCustomAttributes(_DesciptionAttribute, true);
            if (enumAttr.Length == 0) { return string.Empty; }

            var desc = enumAttr[0] as DescriptionAttribute;
            return desc.Description ?? string.Empty;
        }
        /// <summary>
        /// 获取枚举值的说明
        /// </summary>
        public static string _GetNoteByEnumValue<TEnum>(this TEnum EnmValue)
        {
            var EnmType = typeof(TEnum);

            FieldInfo finfo = EnmType.GetField(EnmValue.ToString());
            if (finfo == null) { return string.Empty; }

            var enumAttr = finfo.GetCustomAttributes(_NoteAttribute, true);
            if (enumAttr.Length == 0) { return string.Empty; }

            var desc = enumAttr[0] as NoteAttribute;
            return desc.Note ?? string.Empty;
        }
        /// <summary>
        /// 转成值与说明的字典
        /// </summary>
        public static Dictionary<TNumType, string> _GetValueDescriptionDicFromEnumType<TNumType>(this Type EnmType)
        {
            var ns = System.Enum.GetNames(EnmType);
            var vs = System.Enum.GetValues(EnmType); ;
            var dic = new Dictionary<TNumType, string>(ns.Length);
            for (int i = 0; i < ns.Length; i++)
            {
                FieldInfo finfo = EnmType.GetField(ns[i]);
                object[] enumAttr = finfo.GetCustomAttributes(_DesciptionAttribute, true);
                string remark = string.Empty;
                if (enumAttr.Length > 0)
                {
                    var desc = enumAttr[0] as DescriptionAttribute;
                    if (!string.IsNullOrEmpty(desc.Description))
                    {
                        remark = desc.Description;
                    }
                }
                dic.Add((TNumType)vs.GetValue(i), remark);
            }
            return dic;
        }
        static Type _DesciptionAttribute = typeof(DescriptionAttribute);
        /// <summary>
        /// 获取中文的说明
        /// </summary>
        public static string _GetCnByEnumValue<TEnum>(this TEnum EnmValue)
        {
            var EnmType = typeof(TEnum);

            FieldInfo finfo = EnmType.GetField(EnmValue.ToString());
            if (finfo == null) { return string.Empty; }

            var enumAttr = finfo.GetCustomAttributes(_CnAttribute, true);
            if (enumAttr.Length == 0) { return string.Empty; }

            var atr = enumAttr[0] as CnAttribute;
            return atr.Remaks ?? string.Empty;
        }
        /// <summary>
        /// 转成值与中文的说明的字典
        /// </summary>
        public static Dictionary<TNumType, string> _GetValueCnDicFromEnumType<TNumType>(this Type EnmType)
        {
            var ns = System.Enum.GetNames(EnmType);
            var vs = System.Enum.GetValues(EnmType); ;
            var dic = new Dictionary<TNumType, string>(ns.Length);
            for (int i = 0; i < ns.Length; i++)
            {
                FieldInfo finfo = EnmType.GetField(ns[i]);
                object[] atro = finfo.GetCustomAttributes(_CnAttribute, true);
                string remark = string.Empty;
                if (atro.Length > 0)
                {
                    var atr = atro[0] as CnAttribute;
                    if (!string.IsNullOrEmpty(atr.Remaks))
                    {
                        remark = atr.Remaks;
                    }
                }
                dic.Add((TNumType)vs.GetValue(i), remark);
            }
            return dic;
        }
        static Type _CnAttribute = typeof(CnAttribute);
        /// <summary>
        /// 获取中文的说明
        /// </summary>
        public static string _GetEnByEnumValue<TEnum>(this TEnum EnmValue)
        {
            var EnmType = typeof(TEnum);

            FieldInfo finfo = EnmType.GetField(EnmValue.ToString());
            if (finfo == null) { return string.Empty; }

            var atro = finfo.GetCustomAttributes(_EnAttribute, true);
            if (atro.Length == 0) { return string.Empty; }

            var atr = atro[0] as EnAttribute;
            return atr.Remaks ?? string.Empty;
        }
        /// <summary>
        /// 转成值与中文的说明的字典
        /// </summary>
        public static Dictionary<TNumType, string> _GetValueEnDicFromEnumType<TNumType>(this Type EnmType)
        {
            var ns = System.Enum.GetNames(EnmType);
            var vs = System.Enum.GetValues(EnmType); ;
            var dic = new Dictionary<TNumType, string>(ns.Length);
            for (int i = 0; i < ns.Length; i++)
            {
                FieldInfo finfo = EnmType.GetField(ns[i]);
                object[] atro = finfo.GetCustomAttributes(_EnAttribute, true);
                string remark = string.Empty;
                if (atro.Length > 0)
                {
                    var atr = atro[0] as EnAttribute;
                    if (!string.IsNullOrEmpty(atr.Remaks))
                    {
                        remark = atr.Remaks;
                    }
                }
                dic.Add((TNumType)vs.GetValue(i), remark);
            }
            return dic;
        }
        static Type _EnAttribute = typeof(EnAttribute);
        /// <summary>
        /// 获取枚举
        /// </summary>
        public static TEnum _GetEnumByName<TEnum>(this string Name, TEnum DefValue) where TEnum : struct
        {
            TEnum enm;
            return System.Enum.TryParse<TEnum>(Name, true, out enm) ? enm : DefValue;
        }
        #endregion
    }

    public class NoteAttribute : Attribute
    {
        public string Note { get; set; }

        public NoteAttribute(string note)
        {
            this.Note = note;
        }
    }




}