/// <summary>
/// Parses the xml input string into an instance of the <see cref="NzbDocument"/> class.
/// </summary>
/// <param name="text">An xml string representing the NZB document.</param>
/// <returns>A parsed <see cref="NzbDocument"/>.</returns>
/// <exception cref="ArgumentNullException">ArgumentNullException</exception>
/// <exception cref="ArgumentException">ArgumentException</exception>
/// <exception cref="InvalidNzbDataException">InvalidNzbDataException</exception>
public static NzbDocument Parse(string text)
{
Guard.ThrowIfNullOrEmpty(text, nameof(text));
XDocument doc = XDocument.Parse(text);
XNamespace ns = NzbKeywords.Namespace;
XElement nzbElement = doc.Element(ns + NzbKeywords.Nzb);
if (nzbElement == null)
{
ns = XNamespace.None;
}
nzbElement = doc.Element(ns + NzbKeywords.Nzb);
if (nzbElement == null)
{
throw new InvalidNzbDataException(Resources.Nzb.MissingNzbElement);
}
var context = new NzbParserContext
{
Namespace = ns
};
MultiValueDictionary <string, string> metaData = GetMetaData(context, nzbElement);
IEnumerable <NzbFile> files = GetFiles(context, nzbElement);
return(new NzbDocument(metaData, files));
}
private static List <NzbFile> GetFiles(NzbParserContext context, XContainer nzbElement)
{
return(nzbElement
.Elements(context.Namespace + NzbKeywords.File)
.Select(f => GetFile(context, f))
.ToList());
}
private static List <NzbSegment> GetSegments(NzbParserContext context, XContainer segentsElement)
{
return(segentsElement?
.Elements(context.Namespace + NzbKeywords.Segment)
.Select(GetSegment)
.ToList());
}
private static List <string> GetGroups(NzbParserContext context, XContainer groupsElement)
{
return(groupsElement?
.Elements(context.Namespace + NzbKeywords.Group)
.Select(g => g.Value)
.ToList());
}
private static NntpGroups GetGroups(NzbParserContext context, XContainer groupsElement)
{
IEnumerable <string> groups = groupsElement?
.Elements(context.Namespace + NzbKeywords.Group)
.Select(g => g.Value);
return(new NntpGroups(groups));
}
private static NzbFile GetFile(NzbParserContext context, XElement fileElement)
{
string poster = (string)fileElement.Attribute(NzbKeywords.Poster) ?? string.Empty;
if (!long.TryParse((string)fileElement.Attribute(NzbKeywords.Date) ?? "0", out long unixTimestamp))
{
throw new InvalidNzbDataException(Resources.Nzb.InvalidDateAttriubute);
}
DateTimeOffset date = DateTimeOffset.FromUnixTimeSeconds(unixTimestamp);
string subject = (string)fileElement.Attribute(NzbKeywords.Subject) ?? string.Empty;
List <string> groups = GetGroups(context, fileElement.Element(context.Namespace + NzbKeywords.Groups));
List <NzbSegment> segments = GetSegments(context, fileElement.Element(context.Namespace + NzbKeywords.Segments));
return(new NzbFile(poster, subject, date, groups, segments));
}
private static ILookup <string, string> GetMetaData(NzbParserContext context, XContainer nzbElement)
{
XElement headElement = nzbElement.Element(context.Namespace + NzbKeywords.Head);
if (headElement == null)
{
return(null);
}
IEnumerable <Tuple <string, string> > metaData =
from metaElement in headElement.Elements(context.Namespace + NzbKeywords.Meta)
let typeAttribute = metaElement.Attribute(NzbKeywords.Type)
where typeAttribute != null
select new Tuple <string, string>(typeAttribute.Value, metaElement.Value);
return(metaData.ToLookup(tuple => tuple.Item1, tuple => tuple.Item2));
}
private static IEnumerable <NzbSegment> GetSegments(NzbParserContext context, XContainer segentsElement)
{
IOrderedEnumerable <XElement> elements = segentsElement?
.Elements(context.Namespace + NzbKeywords.Segment)
.OrderBy(element => ((string)element.Attribute(NzbKeywords.Number)).ToIntSafe());
if (elements == null)
{
return(null);
}
long offset = 0;
var segments = new List <NzbSegment>();
foreach (XElement element in elements)
{
NzbSegment segment = GetSegment(element, offset);
segments.Add(segment);
offset += segment.Size;
}
return(segments);
}
private static MultiValueDictionary <string, string> GetMetaData(NzbParserContext context, XContainer nzbElement)
{
XElement headElement = nzbElement.Element(context.Namespace + NzbKeywords.Head);
if (headElement == null)
{
return(null);
}
IEnumerable <Tuple <string, string> > headers =
from metaElement in headElement.Elements(context.Namespace + NzbKeywords.Meta)
let typeAttribute = metaElement.Attribute(NzbKeywords.Type)
where typeAttribute != null
select new Tuple <string, string>(typeAttribute.Value, metaElement.Value);
var dict = new MultiValueDictionary <string, string>();
foreach (Tuple <string, string> header in headers)
{
dict.Add(header.Item1, header.Item2);
}
return(dict);
}
private static IEnumerable <NzbFile> GetFiles(NzbParserContext context, XContainer nzbElement) => nzbElement .Elements(context.Namespace + NzbKeywords.File) .Select(f => GetFile(context, f));
