using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace GSYWApi
{
    /// <summary>
    /// 
    /// </summary>
    public static class TypeParseExtenions
    {
        /// <summary>
        /// 
        /// </summary>
        public static bool IsEmpty(this object[] me)
        {
            if (me == null) return true;

            if (me.Length == 0) return true;

            return false;
        }

        /// <summary>
        /// 
        /// </summary>
        public static bool IsNullOrDBNull(this object me)
        {
            return !(me != null && me != DBNull.Value);
        }

        /// <summary>
        /// 
        /// </summary>
        public static T As<T>(this object me)
        {
            return As<T>(me, default(T));
        }

        /// <summary>
        /// 
        /// </summary>
        public static T As<T>(this object me, T defaultValue)
        {
            T v;
            try
            {
                v = (T)Convert.ChangeType(me, typeof(T));
            }
            catch
            {
                v = defaultValue;
            }
            return v;
        }

        /// <summary>
        /// 
        /// </summary>
        public static DateTime? TryParseToDateTime(this object me)
        {
            if (me.IsNullOrDBNull())
            {
                return null;
            }
            else if (me is DateTime)
            {
                return (DateTime)me;
            }
            else
            {
                DateTime v;
                if (DateTime.TryParse(me.ToString(), out v))
                {
                    return v;
                }
                else
                {
                    return null;
                }
            }
        }

        /// <summary>
        /// 
        /// </summary>
        public static string TryParseToString(this object me)
        {
            return me == null ? string.Empty : Convert.ToString(me);
        }

        /// <summary>
        /// 
        /// </summary>
        public static bool TryParseToBool(this object me, bool defaultValue = false)
        {
            if (me.IsNullOrDBNull())
                return defaultValue;
            if (me is int)
            {
                return (int)me > 0 ? true : false;
            }
            else
            {
                bool v;
                bool.TryParse(me.ToString(), out v);
                return v;
            }
        }

        /// <summary>
        /// 
        /// </summary>
        public static short? TryParseToShort(this object me, short? defaultValue = null)
        {
            short? v = defaultValue;
            try
            {
                v = short.Parse(decimal.Parse(me.ToString()).ToString("0"));
            }
            catch { }

            return v;
        }

        /// <summary>
        /// 
        /// </summary>
        public static int? TryParseToInt(this object me, int? defaultValue = null)
        {
            int? v = defaultValue;
            try
            {
                v = int.Parse(decimal.Parse(me.ToString()).ToString("0"));
            }
            catch { }

            return v;
        }

        /// <summary>
        /// 
        /// </summary>
        public static long? TryParseToLong(this object me, long? defaultValue = null)
        {
            long? v = defaultValue;
            try
            {
                v = long.Parse(decimal.Parse(me.ToString()).ToString("0"));
            }
            catch { }

            return v;
        }

        /// <summary>
        /// 
        /// </summary>
        public static decimal? TryParseToDecimal(this object me, decimal? defaultValue = null)
        {
            decimal? v = defaultValue;
            try
            {
                v = decimal.Parse(me.ToString());
            }
            catch { }

            return v;
        }

        /// <summary>
        /// 
        /// </summary>
        public static double? TryParseToDouble(this object me, double? defaultValue = null)
        {
            double? v = defaultValue;
            try
            {
                v = double.Parse(me.ToString());
            }
            catch { }

            return v;
        }
    }
}