using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using Newtonsoft.Json;

namespace POSV.Utils
{
    public static class ObjectUtils
    {
        //要复制的实例必须可序列化，包括实例引用的其它实例都必须在类定义时加[Serializable]特性。  
        public static T Copy<T>(T source)
        {
            if (!typeof(T).IsSerializable)
            {
                throw new ArgumentException("The type must be serializable." , "source");
            }

            // Don't serialize a null object, simply return the default for that object
            if (Object.ReferenceEquals(source , null))
            {
                return default(T);
            }

            IFormatter formatter = new BinaryFormatter();
            Stream stream = new MemoryStream();
            using (stream)
            {
                formatter.Serialize(stream , source);
                stream.Seek(0 , SeekOrigin.Begin);
                return (T)formatter.Deserialize(stream);
            }
        }

        public static void CopyTo(this object S , object T)
        {
            foreach (var pS in S.GetType().GetProperties())
            {
                foreach (var pT in T.GetType().GetProperties())
                {
                    if (pT.Name != pS.Name) continue;
                    (pT.GetSetMethod()).Invoke(T , new object[]{ pS.GetGetMethod().Invoke( S, null ) });
                }
            };
        }

        private static Dictionary<string , object> _Dic = new Dictionary<string , object>();

        public static TOut TransExp<TIn, TOut>(TIn tIn)
        {
            string key = string.Format("trans_exp_{0}_{1}" , typeof(TIn).FullName , typeof(TOut).FullName);
            if (!_Dic.ContainsKey(key))
            {
                ParameterExpression parameterExpression = Expression.Parameter(typeof(TIn) , "p");
                List<MemberBinding> memberBindingList = new List<MemberBinding>();

                foreach (var item in typeof(TOut).GetProperties())
                {
                    MemberExpression property = Expression.Property(parameterExpression , typeof(TIn).GetProperty(item.Name));
                    MemberBinding memberBinding = Expression.Bind(item , property);
                    memberBindingList.Add(memberBinding);
                }

                MemberInitExpression memberInitExpression = Expression.MemberInit(Expression.New(typeof(TOut)) , memberBindingList.ToArray());
                Expression<Func<TIn , TOut>> lambda = Expression.Lambda<Func<TIn , TOut>>(memberInitExpression , new ParameterExpression[] { parameterExpression });
                Func<TIn , TOut> func = lambda.Compile();
                _Dic[key] = func;
            }
            return ((Func<TIn , TOut>)_Dic[key])(tIn);
        }


        public static T CloneJson<T>(this T source)
        {
            // Don't serialize a null object, simply return the default for that object
            if (Object.ReferenceEquals(source , null))
            {
                return default(T);
            }

            // initialize inner objects individually
            // for example in default constructor some list property initialized with some values,
            // but in 'source' these items are cleaned -
            // without ObjectCreationHandling.Replace default constructor values will be added to result
            var deserializeSettings = new JsonSerializerSettings { ObjectCreationHandling = ObjectCreationHandling.Replace };

            return JsonConvert.DeserializeObject<T>(JsonConvert.SerializeObject(source) , deserializeSettings);
        }
    }

    public static class TransExpV2<TIn, TOut>
    {

        private static readonly Func<TIn , TOut> cache = GetFunc();
        private static Func<TIn , TOut> GetFunc()
        {
            ParameterExpression parameterExpression = Expression.Parameter(typeof(TIn) , "p");
            List<MemberBinding> memberBindingList = new List<MemberBinding>();

            foreach (var item in typeof(TOut).GetProperties())
            {
                if (!item.CanWrite)
                    continue;

                MemberExpression property = Expression.Property(parameterExpression , typeof(TIn).GetProperty(item.Name));
                MemberBinding memberBinding = Expression.Bind(item , property);
                memberBindingList.Add(memberBinding);
            }

            MemberInitExpression memberInitExpression = Expression.MemberInit(Expression.New(typeof(TOut)) , memberBindingList.ToArray());
            Expression<Func<TIn , TOut>> lambda = Expression.Lambda<Func<TIn , TOut>>(memberInitExpression , new ParameterExpression[] { parameterExpression });

            return lambda.Compile();
        }

        public static TOut Trans(TIn tIn)
        {
            return cache(tIn);
        }

    }
}