//-----------------------------------------------------------------------
// <copyright file="DtoDocumentAssembler.cs" company="Deltares">
//  Copyright (c) 2009 Deltares. All rights reserved.
// </copyright>
// <author>B. Faassen</author>
// <email>barry.faassen@deltares.nl</email>
// <date>25-3-2009</date>
// <summary>
//  Conatins a base class for creatin input and output domain objects
//  from xml documents
// </summary>
//-----------------------------------------------------------------------
using System;
using System.Linq;
using System.Reflection;
using System.Xml.Linq;
using Deltares.Standard.IO.DtoAssembler;

namespace Deltares.Standard
{
    /// <summary>
    /// Default implementation for the <see cref="IDtoAssembler"/> interface
    /// </summary>
    /// <remarks>
    /// This base class inherits from <see cref="DtoAssembler"/> this class just fixes 
    /// the dto type to XElement
    /// </remarks>
    /// <typeparam name="T">The domain object type</typeparam>
    public abstract class DtoDocumentAssembler<TDomainInputObject, TDomainOutputObject> : IDtoAssembler<TDomainInputObject, TDomainOutputObject, XDocument>
        where TDomainInputObject : new()
        where TDomainOutputObject : new()
    {
        /// <summary>
        /// Initializes a new instance of the DtoDocumentAssembler class
        /// </summary>
        /// <param name="elementName">Sets the element name</param>
        /// <param name="xsdStream">The text reader stream for reading in ther xsd file which is embedded as an resource</param>
        public DtoDocumentAssembler(string elementName, string elementNamespace, string embeddedXsdPath)
            : this(elementName, elementNamespace, embeddedXsdPath, null, null)
        {
        }

        /// <summary>
        /// Initializes a new instance of the DtoDocumentAssembler class
        /// </summary>
        /// <param name="elementName">Sets the element name</param>
        /// <param name="xsdStream">The text reader stream for reading in ther xsd file which is embedded as an resource</param>
        public DtoDocumentAssembler(string elementName, string elementNamespace, string embeddedXsdPath,
                                    DtoAssembler<TDomainInputObject> inputAssembler, DtoAssembler<TDomainOutputObject> outputAssembler)
        {
            if (elementName == null)
                throw new ArgumentNullException("elementName");

            if (elementNamespace == null)
                throw new ArgumentNullException("elementNamespace");

            this.ElementName = elementName;
            this.ElementNamespace = elementNamespace;
            this.OutputAssembler = outputAssembler;
            this.InputAssembler = inputAssembler;
            //Stream xsdStream = Common.GetEmbeddedFile(Assembly.GetExecutingAssembly(), embeddedXsdPath);
            //this.Schema = XDocument.Load(new StreamReader(xsdStream));
        }

        /// <summary>
        /// Gets the xml element name
        /// </summary>
        public string ElementName { get; private set; }

        /// <summary>
        /// Gets or sets the namespace value for the element
        /// </summary>
        public string ElementNamespace { get; private set; }

        /// <summary>
        /// Gets the xml schema (if any)
        /// </summary>
        public XDocument Schema { get; private set; }

        /// <summary>
        /// 
        /// </summary>
        public DtoAssembler<TDomainInputObject> InputAssembler { get; set; }

        /// <summary>
        /// 
        /// </summary>
        public DtoAssembler<TDomainOutputObject> OutputAssembler { get; set; }

        #region IDtoAssembler<TDomainInputObject,TDomainOutputObject,XDocument> Members

        public virtual TDomainOutputObject CreateOutputObject(XDocument dtoDocument)
        {
            if (dtoDocument == null)
                throw new ArgumentNullException("dtoDocument");

            if (this.OutputAssembler != null)
            {
                // the document should contain the element only once!
                XElement el = (from x in dtoDocument.Descendants()
                               where x.Name.LocalName == this.OutputAssembler.ElementName
                               select x).Single();

                return this.OutputAssembler.CreateDomainObject(el);
            }

            return default(TDomainOutputObject);
        }

        public virtual TDomainInputObject CreateInputObject(XDocument dtoDocument)
        {
            if (dtoDocument == null)
                throw new ArgumentNullException("dtoDocument");

            if (this.InputAssembler != null)
            {
                // the document should contain the element only once!
                XElement el = (from x in dtoDocument.Descendants()
                               where x.Name.LocalName == this.InputAssembler.ElementName
                               select x).Single();

                return this.InputAssembler.CreateDomainObject(el);
            }

            return default(TDomainInputObject);
        }

        public virtual XDocument CreateDataTransferObject(TDomainInputObject domainInputObj)
        {
            var doc = new XDocument(new XDeclaration("1.0", "utf-8", "yes"));

            // add the file identification to the document
            var fileId = new FileIdentification(Assembly.GetCallingAssembly());
            var fileIdAssembler = new FileIdentificationAssembler();

            XNamespace xsi = "http://www.w3.org/2001/XMLSchema-instance";

            XNamespace tns = this.ElementNamespace;
            XNamespace tns1 = fileIdAssembler.ElementNamespace;

            var root = new XElement(tns + this.ElementName,
                                    new XAttribute(XNamespace.Xmlns + "xsi", xsi.NamespaceName),
                                    new XAttribute(XNamespace.Xmlns + "tns", tns.NamespaceName),
                                    new XAttribute(XNamespace.Xmlns + "tns1", tns1.NamespaceName));

            doc.Add(root);
            doc.Root.Add(fileId.ToDto(fileIdAssembler, tns));

            if (this.InputAssembler != null)
            {
                XNamespace tns2 = this.InputAssembler.ElementNamespace;
                root.Add(new XAttribute(XNamespace.Xmlns + "tns2", tns2.NamespaceName));
                doc.Root.Add(domainInputObj.ToDto(this.InputAssembler, tns));
            }

            return doc;
        }

        #endregion

        public TDomainOutputObject CreateOutputObject(string fileName)
        {
            return this.CreateOutputObject(this.CreateDocument(fileName));
        }

        public TDomainInputObject CreateInputObject(string fileName)
        {
            return this.CreateInputObject(this.CreateDocument(fileName));
        }

        private XDocument CreateDocument(string fileName)
        {
            if (!fileName.HasValidStringValue())
                throw new ArgumentNullException("fileName");

            XDocument doc = XDocument.Load(fileName);
            return doc;
        }
    }
}