﻿namespace MaestroPanel.Api
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Runtime.Serialization.Json;
    using System.IO;
    using System.Text;
    using System.Text.RegularExpressions;

    /// <summary>
    /// JSON Serialization and Deserialization Assistant Class
    /// </summary>
    public class JsonHelper<T>
    {
        /// <summary>
        /// JSON Serialization
        /// </summary>
        public static string JsonSerializer(T t)
        {
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
            MemoryStream ms = new MemoryStream();
            ser.WriteObject(ms, t);
            string jsonString = Encoding.UTF8.GetString(ms.ToArray());
            ms.Close();
            //Replace Json Date String                                         
            string p = @"\\/Date\((\d+)\+\d+\)\\/";
            MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertJsonDateToDateString);
            Regex reg = new Regex(p);
            jsonString = reg.Replace(jsonString, matchEvaluator);
            return jsonString;
        }

        /// <summary>
        /// JSON Deserialization
        /// </summary>
        public static T JsonDeserialize(string jsonString)
        {
            //Convert "yyyy-MM-dd HH:mm:ss" String as "\/Date(1319266795390+0800)\/"
            string p = @"\d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2}";
            MatchEvaluator matchEvaluator = new MatchEvaluator(
                ConvertDateStringToJsonDate);
            Regex reg = new Regex(p);
            jsonString = reg.Replace(jsonString, matchEvaluator);
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
            MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
            T obj = (T)ser.ReadObject(ms);
            return obj;
        }

        public static T JsonDeserialize(string jsonString, Type[] extraTypes)
        {
            //Convert "yyyy-MM-dd HH:mm:ss" String as "\/Date(1319266795390+0800)\/"
            string p = @"\d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2}";
            MatchEvaluator matchEvaluator = new MatchEvaluator(
                ConvertDateStringToJsonDate);
            Regex reg = new Regex(p);
            jsonString = reg.Replace(jsonString, matchEvaluator);
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T), extraTypes);
            MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
            T obj = (T)ser.ReadObject(ms);
            return obj;
        }

        /// <summary>
        /// Convert Serialization Time /Date(1319266795390+0800) as String
        /// </summary>
        private static string ConvertJsonDateToDateString(Match m)
        {
            string result = string.Empty;
            DateTime dt = new DateTime(1970, 1, 1);
            dt = dt.AddMilliseconds(long.Parse(m.Groups[1].Value));
            dt = dt.ToLocalTime();
            result = dt.ToString("yyyy-MM-dd HH:mm:ss");
            return result;
        }

        /// <summary>
        /// Convert Date String as Json Time
        /// </summary>
        private static string ConvertDateStringToJsonDate(Match m)
        {
            string result = string.Empty;
            DateTime dt = DateTime.Parse(m.Groups[0].Value);
            dt = dt.ToUniversalTime();
            TimeSpan ts = dt - DateTime.Parse("1970-01-01");
            result = string.Format("\\/Date({0}+0800)\\/", ts.TotalMilliseconds);
            return result;
        }
    }
}