using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Runtime.Serialization.Json;
using System.IO;
using System.Xml;
using System.Data;
using System.Collections;
using System.Web.Script.Serialization;

namespace ThriftCommon
{
    /// <summary>
    /// JSON序列化和反序列化辅助类
    /// 李万锋
    /// Create by Jacky on 2015-05-28
    /// </summary>
    public class JsonHelper
    {
        /// <summary>
        /// JSON序列化
        /// </summary>
        public static string JsonSerializer<T>(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();
            //替换Json的Date字符串
            string p = @"\\/Date\((\d+)\+\d+\)\\/";
            MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertJsonDateToDateString);
            Regex reg = new Regex(p);
            jsonString = reg.Replace(jsonString, matchEvaluator);
            //if (jsonString.StartsWith("["))
            //{
            //    jsonString = jsonString.Remove(0,1);
            //}
            //if (jsonString.EndsWith("]"))
            //{
            //    jsonString = jsonString.Remove(jsonString.Length-1);
            //}
            return jsonString;
        }

        /// <summary>
        /// JSON序列化
        /// </summary>
        /// <param name="RootName">根名称</param>
        public static string JsonSerializer<T>(T t, string RootName)
        {
            DataContractJsonSerializer serializer =
            new DataContractJsonSerializer(typeof(T), RootName);
            MemoryStream ms = new MemoryStream();
            XmlDictionaryWriter w = JsonReaderWriterFactory.CreateJsonWriter(ms);
            w.WriteStartElement("root");
            w.WriteAttributeString("type", "object");
            serializer.WriteObject(w, t);
            w.WriteEndElement();
            w.Flush();
            string retVal = Encoding.UTF8.GetString(ms.ToArray());
            ms.Dispose();

            //替换Json的Date字符串
            string p = @"\\/Date\((\d+)\+\d+\)\\/";
            MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertJsonDateToDateString);
            Regex reg = new Regex(p);
            retVal = reg.Replace(retVal, matchEvaluator);
            return retVal;
        }

        /// <summary>
        /// JSON反序列化
        /// </summary>
        public static T JsonDeserialize<T>(string jsonString)
        {
            //将"yyyy-MM-dd HH:mm:ss"格式的字符串转为"\/Date(1294499956278+0800)\/"格式
            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;
        }

        /// <summary>
        /// 将Json序列化的时间由/Date(1294499956278+0800)转为字符串
        /// </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>
        /// 将时间字符串转为Json时间
        /// </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;
        }

        /// <summary>
        /// Json 字符串 转换为 DataTable数据集合
        /// </summary>
        /// <param name="json"></param>
        /// <returns></returns>
        public static DataTable ToDataTable(string json)
        {
            DataTable dataTable = new DataTable();  //实例化
            DataTable result;
            try
            {
                JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
                javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值
                ArrayList arrayList = javaScriptSerializer.Deserialize<ArrayList>(json);
                if (arrayList.Count > 0)
                {
                    foreach (Dictionary<string, object> dictionary in arrayList)
                    {
                        if (dictionary.Keys.Count<string>() == 0)
                        {
                            result = dataTable;
                            return result;
                        }

                        foreach (string current in dictionary.Keys)
                        {
                            if (!dataTable.Columns.Contains(current))
                            {
                                dataTable.Columns.Add(current, dictionary[current].GetType());
                            }
                        }

                        DataRow dataRow = dataTable.NewRow();
                        foreach (string current in dictionary.Keys)
                        {
                            dataRow[current] = dictionary[current];
                        }

                        dataTable.Rows.Add(dataRow); //循环添加行到DataTable中
                    }
                }
            }
            catch
            {
            }
            result = dataTable;
            return result;
        }


        // 将 DataTable 序列化成 json 字符串  
        public static string DataTableToJson(DataTable dt)
        {
            if (dt == null || dt.Rows.Count == 0)
            {
                return "\"\"";
            }
            JavaScriptSerializer myJson = new JavaScriptSerializer();

            List<Dictionary<string, object>> list = new List<Dictionary<string, object>>();

            foreach (DataRow dr in dt.Rows)
            {
                Dictionary<string, object> result = new Dictionary<string, object>();
                foreach (DataColumn dc in dt.Columns)
                {
                    result.Add(dc.ColumnName, dr[dc].ToString());
                }
                list.Add(result);
            }
            return myJson.Serialize(list);
        }

        // 将对象序列化成 json 字符串  
        public static string ObjectToJson(object obj)
        {
            if (obj == null)
            {
                return string.Empty;
            }
            JavaScriptSerializer myJson = new JavaScriptSerializer();

            return myJson.Serialize(obj);
        }

        // 将 json 字符串反序列化成对象  
        public static object JsonToObject(string json)
        {
            if (string.IsNullOrEmpty(json))
            {
                return null;
            }
            JavaScriptSerializer myJson = new JavaScriptSerializer();

            return myJson.DeserializeObject(json);
        }

        // 将 json 字符串反序列化成对象  
        public static T JsonToObject<T>(string json)
        {
            if (string.IsNullOrEmpty(json))
            {
                return default(T);
            }
            JavaScriptSerializer myJson = new JavaScriptSerializer();
            myJson.MaxJsonLength = Int32.MaxValue;
            return myJson.Deserialize<T>(json);
        }
    }


    public static class JSON
    {
        public static T parse<T>(string jsonString)
        {
            using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString)))
            {
                return (T)new DataContractJsonSerializer(typeof(T)).ReadObject(ms);
            }
        }

    }
}