using System;
using System.Collections.Generic;
using System.Linq;
using System.ComponentModel;
using System.Globalization;
using System.Configuration;
using System.Drawing.Imaging;
using System.Drawing;
using System.IO;
using System.Web;

/// <summary>
/// publicFun 的摘要描述
/// </summary>
public class publicFun
{
    public publicFun()
    {
        //
        // TODO: 在這裡新增建構函式邏輯
        //
    }
    public static Dictionary<int, string> enum_desc<T>()
    {
        //var v1 = typeof(type).GetEnumNames(); // string[] of enum values
        var v2 = typeof(T).GetEnumValues().Cast<int>().ToList(); // int[] of enum values
                                                                 //var v3 = typeof(type).GetEnumValues().Cast<type>().ToList(); // type[] of enum values
        var v4 = publicFun.GetDescriptions<T>().ToList(); // string[] of dnum descriptioins

        //var v5 = Enum<type>.GetNames(); // ==v1
        //var v6 = Enum<type>.GetValues(); // ==v3

        //var v7 = Enum<type>.GetNames().ToDictionary(x => x, x => (int)Enum<type>.Parse(x)); // v7["Personal"]... int[]
        ////var v8 = v7.ToDictionary(x => x.Key, x => Enum<type>.GetAttribute<EnumMemberAttribute>(x.Key).Value); // not work

        //寫成公用
        var dictionary = new Dictionary<int, string>();
        for (int i = 0; i < v2.Count; i++)
        {
            dictionary.Add(v2[i], v4[i]);
        }
        return dictionary;
    }

    public static IEnumerable<string> GetDescriptions<T>()
    { 
        var attributes = typeof(T).GetMembers()
            .SelectMany(member => member.GetCustomAttributes(typeof(DescriptionAttribute), true)
            .Cast<DescriptionAttribute>())
            .ToList();

        return attributes.Select(x => x.Description);
    }

    public static class Enum<T> where T : struct, IComparable, IFormattable, IConvertible
    {
        public static IEnumerable<T> GetValues()
        {
            return (T[])Enum.GetValues(typeof(T));
        }
        public static IEnumerable<string> GetNames()
        {
            return Enum.GetNames(typeof(T));
        }

        public static T Parse(string @enum)
        {
            return (T)Enum.Parse(typeof(T), @enum);
        }

        public static S GetAttribute<S>(string @enum) where S : Attribute
        {   // not working
            return (S)typeof(T).GetMember(@enum)[0]
                               .GetCustomAttributes(typeof(S), false)
                               .SingleOrDefault();
            // var v7 = Enum<type>.GetNames().ToDictionary(x => x, x => (int)Enum<type>.Parse(x)); // v7["Personal"]... int[]
            // var v8 = v7.ToDictionary(x => x.Key, x => Enum<type>.GetAttribute<EnumMemberAttribute>(x.Key).Value);
        }

        // class EnumConverter
        // https://stackoverflow.com/questions/3816718/how-to-get-an-array-of-all-enum-values-in-c
        // https

    }

    public static string chagenDate(DateTime? date)//因為欄位值是nullable, 所以把null的處理拉進函數做
    { //可改公用
      //農曆年
        ChineseLunisolarCalendar chineseDate = new ChineseLunisolarCalendar();
        try
        {
            if (date != null)
            {
                DateTime d = date ?? DateTime.Now;
                int yy = chineseDate.GetYear(d) - 1911;
                int mm = chineseDate.GetMonth(d);
                int dd = chineseDate.GetDayOfMonth(d);
                string dstr = $"民{yy}年{mm:00}月{dd:00}日";
                return dstr;
            }
        }
        catch
        { //try catch可能會很慢, 已知條件先判斷
          //return null;
        }
        return null;
        //民國年
        //System.Globalization.TaiwanCalendar tc = new System.Globalization.TaiwanCalendar();
        // tc.GetYear(d), tc.GetMonth(d), tc.GetDayOfMonth(d)
    }

    #region 刪除檔案 for api
    public void DeleteFile(string filePath)
    {
        string path = HttpContext.Current.Server.MapPath(filePath);
        FileInfo FileInfo = new FileInfo(path);
        if (FileInfo.Exists)
        {
            FileInfo.Delete();
        }
    }

    #endregion

}