private static async Task <EpubNavigationHead> ReadNavigationHeadAsync(XmlReader reader)
{
EpubNavigationHead result = new EpubNavigationHead();
//"ncx:head" is our starting point
bool headFound = await reader.ReadToFollowingAsync("head", "http://www.daisy.org/z3986/2005/ncx/");
if (!headFound)
{
throw new Exception("EPUB parsing error: head section not found in the .toc file.");
}
while (await reader.ReadAsync() && !(reader.NodeType == XmlNodeType.EndElement && reader.LocalName == "head"))
{
if (reader.LocalName.ToLowerInvariant() == "meta")
{
EpubNavigationHeadMeta meta = new EpubNavigationHeadMeta();
while (reader.MoveToNextAttribute())
{
switch (reader.LocalName.ToLowerInvariant())
{
case "name":
meta.Name = reader.Value;
break;
case "content":
meta.Content = reader.Value;
break;
case "scheme":
meta.Scheme = reader.Value;
break;
}
}
if (String.IsNullOrWhiteSpace(meta.Name))
{
throw new Exception("Incorrect EPUB navigation meta: meta name is missing");
}
if (meta.Content == null)
{
throw new Exception("Incorrect EPUB navigation meta: meta content is missing");
}
result.Add(meta);
}
}
return(result);
}
private static EpubNavigationHead ReadNavigationHead(XElement headNode)
{
EpubNavigationHead result = new EpubNavigationHead();
foreach (XElement metaNode in headNode.Elements())
{
if (string.Compare(metaNode.Name.LocalName, "meta", StringComparison.OrdinalIgnoreCase) == 0)
{
EpubNavigationHeadMeta meta = new EpubNavigationHeadMeta();
foreach (XAttribute metaNodeAttribute in metaNode.Attributes())
{
string attributeValue = metaNodeAttribute.Value;
switch (metaNodeAttribute.Name.LocalName.ToLowerInvariant())
{
case "name":
meta.Name = attributeValue;
break;
case "content":
meta.Content = attributeValue;
break;
case "scheme":
meta.Scheme = attributeValue;
break;
}
}
if (string.IsNullOrWhiteSpace(meta.Name))
{
throw new Exception("Incorrect EPUB navigation meta: meta name is missing.");
}
if (meta.Content == null)
{
throw new Exception("Incorrect EPUB navigation meta: meta content is missing.");
}
result.Add(meta);
}
}
return(result);
}
