private static EpubNavigationTarget ReadNavigationTarget(XElement navigationTargetNode)
{
var result = new EpubNavigationTarget();
foreach (var navigationPageTargetNodeAttribute in navigationTargetNode.Attributes())
{
var attributeValue = navigationPageTargetNodeAttribute.Value;
switch (navigationPageTargetNodeAttribute.Name.LocalName.ToLowerInvariant())
{
case "id":
result.Id = attributeValue;
break;
case "value":
result.Value = attributeValue;
break;
case "class":
result.Class = attributeValue;
break;
case "playOrder":
result.PlayOrder = attributeValue;
break;
}
}
if (string.IsNullOrWhiteSpace(result.Id))
{
throw new Exception("Incorrect EPUB navigation target: navigation target ID is missing.");
}
foreach (var navigationTargetChildNode in navigationTargetNode.Elements())
{
switch (navigationTargetChildNode.Name.LocalName.ToLowerInvariant())
{
case "navlabel":
var navigationLabel = ReadNavigationLabel(navigationTargetChildNode);
result.NavigationLabels.Add(navigationLabel);
break;
case "content":
var content = ReadNavigationContent(navigationTargetChildNode);
result.Content = content;
break;
}
}
if (!result.NavigationLabels.Any())
{
throw new Exception("Incorrect EPUB navigation target: at least one navLabel element is required.");
}
return(result);
}
private static EpubNavigationList ReadNavigationList(XElement navigationListNode)
{
EpubNavigationList result = new EpubNavigationList();
foreach (XAttribute navigationListNodeAttribute in navigationListNode.Attributes())
{
string attributeValue = navigationListNodeAttribute.Value;
switch (navigationListNodeAttribute.Name.LocalName.ToLowerInvariant())
{
case "id":
result.Id = attributeValue;
break;
case "class":
result.Class = attributeValue;
break;
}
}
foreach (XElement navigationListChildNode in navigationListNode.Elements())
{
switch (navigationListChildNode.Name.LocalName.ToLowerInvariant())
{
case "navlabel":
EpubNavigationLabel navigationLabel = ReadNavigationLabel(navigationListChildNode);
result.NavigationLabels.Add(navigationLabel);
break;
case "navTarget":
EpubNavigationTarget navigationTarget = ReadNavigationTarget(navigationListChildNode);
result.NavigationTargets.Add(navigationTarget);
break;
}
}
if (!result.NavigationLabels.Any())
{
throw new Exception("Incorrect EPUB navigation page target: at least one navLabel element is required.");
}
return(result);
}
