// /**
//  * File: Syncable.cs
//  * Author: haraldwolff
//  *
//  * This file and it's content is copyrighted by the Author and / or copyright holder.
//  * Any use wihtout proper permission is illegal and may lead to legal actions.
//  *
//  *
//  **/
using System;
using System.IO;
using System.Collections.Generic;
using ln.logging;
using System.Runtime.Serialization;
using System.Xml.Serialization;
using System.Reflection;
using System.Text;
using ln.types.serialize;
namespace ln.types.sync
{
    public class Synced : Attribute
    {
    }

    public class Unsynced : Attribute
    {
    }

    public abstract class Syncable
    {
        public String FileName { get; set; }

        public Syncable()
        {
        }
        public Syncable(string fileName)
        {
            FileName = fileName;
            Load();
        }

        public void Load()
        {
            using (ObjectReader objectReader = new ObjectReader(FileName))
            {
                objectReader.ReadThis(this);
            }
        }

        public void Sync()
        {
            using (FileStream fileStream = new FileStream(FileName, FileMode.OpenOrCreate))
            {
                ObjectWriter objectWriter = new ObjectWriter(fileStream);
                objectWriter.Write(this);
                fileStream.Close();
            }
        }

        public virtual void Restore(Dictionary<string,object> keyValues)
        {
            if (keyValues.ContainsKey("sync.timestamp"))
                Logging.Log(LogLevel.DEBUG, "Syncable restoring from state of {0}",keyValues["sync.timestamp"]);


            foreach (FieldInfo fieldInfo in GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance))
            {
                if (fieldInfo.GetCustomAttribute<Synced>() != null)
                {
                    string key = String.Format("field.{0}", fieldInfo.Name);
                    if (keyValues.ContainsKey(key))
                    {
                        fieldInfo.SetValue(this,keyValues[key]);
                    }
                }
            }

        }
        public virtual void Collect(Dictionary<string, object> keyValues)
        {
            keyValues["sync.timestamp"] = DateTime.Now;
            Logging.Log(LogLevel.DEBUG, "Syncable: collectiong state at {0}", keyValues["sync.timestamp"]);

            foreach (FieldInfo fieldInfo in GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance))
            {
                if (fieldInfo.GetCustomAttribute<Synced>() != null)
                {
                    string key = String.Format("field.{0}", fieldInfo.Name);
                    object value = fieldInfo.GetValue(this);

                    keyValues.Add(key, value);
                }
            }

        }

        private byte[] Serialize(object o)
        {
            if (o == null)
                return new byte[0];

            XmlSerializer xmlSerializer = new XmlSerializer(o.GetType());
            MemoryStream memoryStream = new MemoryStream();
            xmlSerializer.Serialize(memoryStream, o);
            byte[] result = memoryStream.ToArray();

            Logging.Log(LogLevel.DEBUG, "Serialized: {0}",Encoding.UTF8.GetString(result));

            return result;
        }

        private object Unserialize(byte[] buffer,Type type)
        {
            if ((type == null) || (buffer.Length == 0))
                return null;

            MemoryStream memoryStream = new MemoryStream(buffer);
            XmlSerializer xmlSerializer = new XmlSerializer(type);

            return xmlSerializer.Deserialize(memoryStream);
        }


    }
}