/* Copyright (c) 2006-2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* Change history
* Oct 13 2008 Joe Feser joseph.feser@gmail.com
* Converted ArrayLists and other .NET 1.1 collections to use Generics
* Combined IExtensionElement and IExtensionElementFactory interfaces
*
*/
using System;
using System.IO;
using System.Collections;
using System.Text;
using System.Xml;
using Google.GData.Client;
namespace Google.GData.Extensions {
/// <summary>
/// GData schema extension describing a nested feed link.
/// </summary>
public class FeedLink : IExtensionElementFactory
{
/// <summary>holds the href property</summary>
private string href;
/// <summary>holds the readOnly property</summary>
private bool readOnly;
/// <summary>holds the feed property</summary>
private AtomFeed feed;
/// <summary>holds the rel attribute of the EntyrLink element</summary>
private string rel;
private bool readOnlySet;
private int countHint;
/// <summary>
/// constructor
/// </summary>
public FeedLink()
{
this.countHint = -1;
this.readOnly = true;
}
/// <summary>
/// Entry URI
/// </summary>
public string Href
{
get { return href;}
set { href = value;}
}
/// <summary>
/// Read only flag.
/// </summary>
public bool ReadOnly
{
get { return readOnly;}
set { this.readOnly = value; this.readOnlySet = true;}
}
/// <summary>
/// Count hint.
/// </summary>
public int CountHint
{
get { return countHint;}
set { countHint = value;}
}
/// <summary>
/// Nested entry (optional).
/// </summary>
public AtomFeed Feed
{
get { return feed;}
set { feed = value;}
}
//////////////////////////////////////////////////////////////////////
/// <summary>accessor method public string Rel</summary>
/// <returns> </returns>
//////////////////////////////////////////////////////////////////////
public string Rel
{
get {return this.rel;}
set {this.rel = value;}
}
/////////////////////////////////////////////////////////////////////////////
#region FeedLink Parser
//////////////////////////////////////////////////////////////////////
/// <summary>Parses an xml node to create an FeedLink object.</summary>
/// <param name="node">feedLink node</param>
/// <returns> the created FeedLink object</returns>
//////////////////////////////////////////////////////////////////////
public static FeedLink ParseFeedLink(XmlNode node)
{
Tracing.TraceCall();
FeedLink link = null;
Tracing.Assert(node != null, "node should not be null");
if (node == null)
{
throw new ArgumentNullException("node");
}
object localname = node.LocalName;
if (localname.Equals(GDataParserNameTable.XmlFeedLinkElement))
{
link = new FeedLink();
if (node.Attributes != null)
{
if (node.Attributes[GDataParserNameTable.XmlAttributeHref] != null)
{
link.Href = node.Attributes[GDataParserNameTable.XmlAttributeHref].Value;
}
if (node.Attributes[GDataParserNameTable.XmlAttributeReadOnly] != null)
{
link.ReadOnly = node.Attributes[GDataParserNameTable.XmlAttributeReadOnly].Value.Equals(Utilities.XSDTrue);
}
if (node.Attributes[GDataParserNameTable.XmlAttributeRel] != null)
{
link.Rel = node.Attributes[GDataParserNameTable.XmlAttributeRel].Value;
}
if (node.Attributes[GDataParserNameTable.XmlAttributeCountHint] != null)
{
try
{
link.CountHint = Int32.Parse(node.Attributes[GDataParserNameTable.XmlAttributeCountHint].Value);
}
catch (FormatException fe)
{
throw new ArgumentException("Invalid g:feedLink/@countHint.", fe);
}
}
}
if (node.HasChildNodes)
{
XmlNode feedChild = node.FirstChild;
while (feedChild != null && feedChild is XmlElement)
{
if (feedChild.LocalName == AtomParserNameTable.XmlFeedElement &&
feedChild.NamespaceURI == BaseNameTable.NSAtom)
{
if (link.Feed == null)
{
link.Feed = new AtomFeed(null, new Service());
Stream feedStream =
new MemoryStream(ASCIIEncoding.Default.GetBytes(feedChild.OuterXml));
link.Feed.Parse(feedStream, AlternativeFormat.Atom);
}
else
{
throw new ArgumentException("Only one feed is allowed inside the g:feedLink");
}
}
feedChild = feedChild.NextSibling;
}
}
}
return link;
}
#endregion
#region overloaded from IExtensionElementFactory
//////////////////////////////////////////////////////////////////////
/// <summary>Parses an xml node to create a Where object.</summary>
/// <param name="node">the node to parse node</param>
/// <param name="parser">the xml parser to use if we need to dive deeper</param>
/// <returns>the created Where object</returns>
//////////////////////////////////////////////////////////////////////
public IExtensionElementFactory CreateInstance(XmlNode node, AtomFeedParser parser)
{
return FeedLink.ParseFeedLink(node);
}
//////////////////////////////////////////////////////////////////////
/// <summary>Returns the constant representing this XML element.</summary>
//////////////////////////////////////////////////////////////////////
public string XmlName
{
get { return GDataParserNameTable.XmlFeedLinkElement;}
}
//////////////////////////////////////////////////////////////////////
/// <summary>Returns the constant representing this XML element.</summary>
//////////////////////////////////////////////////////////////////////
public string XmlNameSpace
{
get { return BaseNameTable.gNamespace; }
}
//////////////////////////////////////////////////////////////////////
/// <summary>Returns the constant representing this XML element.</summary>
//////////////////////////////////////////////////////////////////////
public string XmlPrefix
{
get { return BaseNameTable.gDataPrefix; }
}
#endregion
#region overloaded for persistence
/// <summary>
/// Persistence method for the FeedLink object
/// </summary>
/// <param name="writer">the xmlwriter to write into</param>
public void Save(XmlWriter writer)
{
if (Utilities.IsPersistable(this.Href) || this.Feed != null)
{
writer.WriteStartElement(XmlPrefix, XmlName, XmlNameSpace);
if (Utilities.IsPersistable(this.Href))
{
writer.WriteAttributeString(GDataParserNameTable.XmlAttributeHref, this.Href);
}
// do not save the default
if (this.readOnlySet)
{
writer.WriteAttributeString(GDataParserNameTable.XmlAttributeReadOnly,
Utilities.ConvertBooleanToXSDString(this.ReadOnly));
}
if (Utilities.IsPersistable(this.Rel))
{
writer.WriteAttributeString(GDataParserNameTable.XmlAttributeRel, this.Rel);
}
if (this.countHint > -1)
{
writer.WriteAttributeString(GDataParserNameTable.XmlAttributeCountHint, this.countHint.ToString());
}
if (Feed != null)
{
Feed.SaveToXml(writer);
}
writer.WriteEndElement();
}
}
#endregion
}
}
