using System;
using System.Collections.Generic;
using System.Text;
using System.Xml.Serialization;

namespace DTS.DASLib.Service
{
    /// <summary>
    /// This is a simple serializable dictionary
    /// I'm using it for storing user attributes on slicepro/1.5 right now, but it's probably suitable for any dictionary
    /// that needs to be serialized
    /// </summary>
    /// <typeparam name="TKey"></typeparam>
    /// <typeparam name="TValue"></typeparam>
    [XmlRoot("SerializedDictionary")]
    public class SerializableDictionary<TKey, TValue>
        : Dictionary<TKey, TValue>, IXmlSerializable
    {
        #region IXmlSerializable Members
        public System.Xml.Schema.XmlSchema GetSchema()
        {
            return null;
        }

        public void ReadXml(System.Xml.XmlReader reader)
        {
            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

            bool wasEmpty = reader.IsEmptyElement;
            if (wasEmpty)
                return;

            reader.Read();//document
            reader.ReadStartElement();//serializeddictionary

            while (reader.NodeType != System.Xml.XmlNodeType.EndElement && reader.NodeType != System.Xml.XmlNodeType.None)
            {
                reader.ReadStartElement("Item");

                reader.ReadStartElement("Key");
                TKey key = (TKey)keySerializer.Deserialize(reader);
                reader.ReadEndElement();

                reader.ReadStartElement("Value");
                TValue value = (TValue)valueSerializer.Deserialize(reader);
                reader.ReadEndElement();

                this.Add(key, value);

                reader.ReadEndElement();               
                reader.MoveToContent();
            }
            if (reader.NodeType != System.Xml.XmlNodeType.None)
            {
                reader.ReadEndElement();
            }
        }

        public void WriteXml(System.Xml.XmlWriter writer)
        {
            writer.WriteStartDocument();
            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));
            writer.WriteStartElement("SerializedDictionary");
            foreach (TKey key in this.Keys)
            {
                writer.WriteStartElement("Item");

                    writer.WriteStartElement("Key");
                    keySerializer.Serialize(writer, key);
                    writer.WriteEndElement();//key

                    writer.WriteStartElement("Value");
                    TValue value = this[key];
                    valueSerializer.Serialize(writer, value);
                    writer.WriteEndElement();//value

                writer.WriteEndElement();//item
                writer.Flush();
            }
            writer.WriteEndElement();//SerializedDictionary
            writer.WriteEndDocument();
        }
        #endregion
    }
}