/// <summary>
/// Parses an opening tag like '<div>'. Starts with the input stream
/// pointing to the opening < character.
/// </summary>
private Element ProcessTagOpenState(Element currentElement)
{
if (!_characterStream.MoveNext())
{
_document.ConformanceLevel *= 0.8f;
return(null);
}
switch (_characterStream.Current)
{
case '!':
_characterStream.State = HtmlStates.MarkupDeclarationOpen;
return(currentElement);
case '/':
_characterStream.State = HtmlStates.EndTagOpen;
return(currentElement);
}
var startPosition = _characterStream.CurrentPosition;
string tagName = null;
var selfClosing = false;
using (var nameBuffer = _stringBuilderFactory.Create(_maximumNameLength))
{
char?terminator;
_characterStream.State = HtmlStates.TagName;
if (_stringParser.TakeUntil(nameBuffer, _maximumNameLength, c => char.IsWhiteSpace(c) || c == '>' || c == '/', out terminator))
{
tagName = nameBuffer.ToString().ToLower();
if (!terminator.HasValue || terminator == '/')
{
_characterStream.State = HtmlStates.SelfClosingStartTag;
if (_stringParser.Peek() == '>')
{
_stringParser.TakeOne();
}
else
{
_document.ConformanceLevel *= 0.9f;
}
}
else if (terminator == '>')
{
_characterStream.State = _voidElements.Contains(tagName)
? HtmlStates.SelfClosingStartTag
: HtmlStates.Data;
}
else
{
_characterStream.State = HtmlStates.AttributeName;
selfClosing = _voidElements.Contains(tagName);
}
}
else
{
_document.ConformanceLevel *= 0.9f;
nameBuffer.Clear();
_stringParser.Take(nameBuffer, _maximumNameLength);
var buffer = nameBuffer.ToString().ToLower();
_characterStream.State = HtmlStates.Data;
foreach (var name in _allElements)
{
if (buffer.StartsWith(name))
{
nameBuffer.Clear();
_characterStream.Reset(startPosition);
_stringParser.Take(nameBuffer, name.Length);
tagName = nameBuffer.ToString();
_characterStream.State = HtmlStates.AttributeName;
selfClosing = _voidElements.Contains(tagName);
break;
}
}
if (tagName == null)
{
_document.ConformanceLevel *= 0.6f;
}
}
}
var attributes = _characterStream.State == HtmlStates.AttributeName ? ParseAttributes(selfClosing) : null;
if (currentElement != null)
{
var parentElement = currentElement;
switch (tagName)
{
case "html":
case "body":
case "form":
case "header":
case "footer":
// These elements are not parsed and contain no details. They are included in the output
// only as containers for their children
currentElement = new UnsupportedElement {
Attributes = attributes, SuppressOutput = false
};
break;
case "p":
case "li":
// These elements are treated as paragraphs in other markup formats, for
// example in markdown they will have a blank line above them to create a
// paragraph break.
currentElement = new ParagraphElement {
Attributes = attributes
};
break;
case "blockquote":
currentElement = new ParagraphElement
{
Attributes = attributes,
Styles = new Dictionary <string, string>
{
{ "margin-top", "10px" },
{ "margin-bottom", "10px" },
{ "margin-left", "50px" },
{ "padding-left", "15px" },
{ "border-left", "3px solid #ccc" }
}
};
break;
case "div":
// Divs are tricky because some pwople use them to group elements with similar
// style and other people used them instead of paragraphs. Since divs are by
// default block elements it makes more sense in most cases to treat them link
// paragraphs unless they have paraphraphs or other divs within them.
currentElement = new ContainerElement {
ContainerType = ContainerTypes.Division, Attributes = attributes
};
break;
case "span":
// These elements are treated as inline text. For example in markdown
// these are rendered without an extra blank line and are therefore rendered
// as part of the prior paragraph
currentElement = new SpanElement {
Attributes = attributes
};
break;
case "a":
// Anchor tags are a special case
if (attributes != null && attributes.ContainsKey("href"))
{
currentElement = new AnchorElement {
LinkAddress = attributes["href"]
}
}
;
else
{
currentElement = new UnsupportedElement {
Attributes = attributes
}
};
break;
case "iframe":
case "img":
// Image tags are a special case
if (attributes != null && attributes.ContainsKey("src"))
{
var alt = attributes.ContainsKey("alt") ? attributes["alt"] : null;
currentElement = new ImageElement {
LinkAddress = attributes["src"], AltText = alt
};
}
else
{
currentElement = new UnsupportedElement {
Attributes = attributes
};
}
break;
case "h1":
currentElement = new HeadingElement {
Level = 1
};
break;
case "h2":
currentElement = new HeadingElement {
Level = 2
};
break;
case "h3":
currentElement = new HeadingElement {
Level = 3
};
break;
case "h4":
currentElement = new HeadingElement {
Level = 4
};
break;
case "h5":
currentElement = new HeadingElement {
Level = 5
};
break;
case "h6":
currentElement = new HeadingElement {
Level = 6
};
break;
case "strong":
case "b":
// Bold is represented as an inline style
currentElement = new FormattedElement
{
ElementType = ElementTypes.InlineText,
Styles = new Dictionary <string, string>
{
{ "font-weight", "bold" }
}
};
break;
case "cite":
case "q":
case "i":
case "em":
// Italic is represented as an inline style
currentElement = new FormattedElement
{
ElementType = ElementTypes.InlineText,
Styles = new Dictionary <string, string>
{
{ "font-style", "italic" }
}
};
break;
case "u":
// Underline is represented as an inline style
currentElement = new FormattedElement
{
ElementType = ElementTypes.InlineText,
Styles = new Dictionary <string, string>
{
{ "text-decoration", "underline" }
}
};
break;
case "small":
// Small is represented as an inline style
currentElement = new FormattedElement
{
ElementType = ElementTypes.InlineText,
Styles = new Dictionary <string, string>
{
{ "font-size", "smaller" }
}
};
break;
case "sup":
// Superscript is represented as an inline style
currentElement = new FormattedElement
{
ElementType = ElementTypes.InlineText,
Styles = new Dictionary <string, string>
{
{ "vertical-align", "super" },
{ "font-size", "smaller" }
}
};
break;
case "sub":
// Subscript is represented as an inline style
currentElement = new FormattedElement
{
ElementType = ElementTypes.InlineText,
Styles = new Dictionary <string, string>
{
{ "vertical-align", "sub" },
{ "font-size", "smaller" }
}
};
break;
case "br":
currentElement = new BreakElement {
BreakType = BreakTypes.LineBreak
};
break;
case "hr":
currentElement = new BreakElement {
BreakType = BreakTypes.HorizontalRule
};
break;
case "ul":
currentElement = new ContainerElement {
ContainerType = ContainerTypes.BulletList, Attributes = attributes
};
break;
case "ol":
currentElement = new ContainerElement {
ContainerType = ContainerTypes.NumberedList, Attributes = attributes
};
break;
case "table":
currentElement = new ContainerElement {
ContainerType = ContainerTypes.Table, Attributes = attributes
};
break;
case "tr":
currentElement = new ContainerElement {
ContainerType = ContainerTypes.TableDataRow, Attributes = attributes
};
break;
case "th":
currentElement = new ContainerElement {
ContainerType = ContainerTypes.TableHeaderRow, Attributes = attributes
};
break;
case "td":
currentElement = new ContainerElement {
ContainerType = ContainerTypes.TableDataCell, Attributes = attributes
};
break;
default:
// All other elements will be excluded from the output document, but will
// be parsed just so that we know where they and and the next valid element
// begins.
currentElement = new UnsupportedElement {
Attributes = attributes
};
break;
}
var styleElement = currentElement as IStyleElement;
if (styleElement != null && attributes != null)
{
if (attributes.ContainsKey("class"))
{
styleElement.ClassNames = attributes["class"];
attributes.Remove("class");
}
if (attributes.ContainsKey("style"))
{
if (styleElement.Styles == null)
{
styleElement.Styles = new Dictionary <string, string>();
}
var styles = attributes["style"].Split(';').Select(s => s.Trim()).Where(s => s.Length > 0);
foreach (var style in styles)
{
var colonPos = style.IndexOf(':');
if (colonPos > 0 && colonPos < style.Length - 1)
{
var name = style.Substring(0, colonPos).Trim().ToLower();
var value = style.Substring(colonPos + 1).Trim().ToLower();
if (!styleElement.Styles.ContainsKey(name))
{
styleElement.Styles[name] = value;
}
}
else
{
_document.ConformanceLevel *= 0.9f;
}
}
attributes.Remove("style");
}
}
currentElement.Name = tagName;
currentElement.Parent = parentElement;
if (parentElement.SuppressOutput)
{
currentElement.SuppressOutput = true;
}
if (parentElement.Children == null)
{
parentElement.Children = new List <IDocumentElement>();
}
parentElement.Children.Add(currentElement);
if (!Begin(currentElement))
{
return(null);
}
}
return(currentElement);
}
private bool CheckTable(string trimmedLine)
{
Func <string, List <string> > splitColumns = l =>
{
var columns = l.Split('|').Select(c => c.Trim()).ToList();
if (trimmedLine.StartsWith("|"))
{
columns.RemoveAt(0);
}
if (trimmedLine.EndsWith("|"))
{
columns.RemoveAt(columns.Count - 1);
}
return(columns);
};
if ((_characterStream.State == MarkdownStates.ParagraphBreak && trimmedLine.Contains('|')) ||
((_characterStream.State == MarkdownStates.Paragraph || _characterStream.State == MarkdownStates.Heading) && trimmedLine[0] == '|'))
{
PushElement(new ContainerElement
{
Name = "table",
ContainerType = ContainerTypes.Table,
ChildLayout = new List <string>()
});
PushElement(new ContainerElement
{
Name = "thead",
ContainerType = ContainerTypes.TableHeader,
});
_characterStream.State = MarkdownStates.TableHeadings;
}
if (_characterStream.State == MarkdownStates.TableHeadings)
{
if (trimmedLine.All(c => char.IsWhiteSpace(c) || "|-:".Contains(c)))
{
var columnFormats = splitColumns(trimmedLine);
for (var i = 0; i < columnFormats.Count; i++)
{
var format = columnFormats[i];
columnFormats[i] = string.Empty;
if (format.Length > 1)
{
if (format[format.Length - 1] == ':')
{
columnFormats[i] = format[0] == ':' ? "center" : "right";
}
else if (format[0] == ':')
{
columnFormats[i] = "left";
}
}
}
var tableElement = FindPriorElement <ContainerElement>(c => c.ContainerType == ContainerTypes.Table);
if (tableElement != null)
{
tableElement.ChildLayout = columnFormats;
}
PopElement(); // Pop the TableHeader
PushElement(new ContainerElement
{
Name = "tbody",
ContainerType = ContainerTypes.TableBody,
});
_characterStream.State = MarkdownStates.TableRow;
}
else
{
PushElement(new ContainerElement {
Name = "tr", ContainerType = ContainerTypes.TableHeaderRow
});
var columns = splitColumns(trimmedLine);
foreach (var column in columns)
{
PushElement(new ContainerElement {
Name = "th", ContainerType = ContainerTypes.TableDataCell
});
ParseText(column);
PopElement(); // Pop the th off the stack, adding it to the tr
}
PopElement(); // Pop the tr, adding it to the table
}
return(true);
}
if (_characterStream.State == MarkdownStates.TableRow)
{
var tableElement = FindPriorElement <ContainerElement>(c => c.ContainerType == ContainerTypes.Table);
var columnFormats = tableElement == null ? null : (List <string>)tableElement.ChildLayout;
PushElement(new ContainerElement {
Name = "tr", ContainerType = ContainerTypes.TableDataRow
});
var columns = splitColumns(trimmedLine);
for (var i = 0; i < columns.Count; i++)
{
var td = new ContainerElement {
Name = "td", ContainerType = ContainerTypes.TableDataCell
};
if (columnFormats != null && columnFormats.Count > i && !string.IsNullOrEmpty(columnFormats[i]))
{
td.Attributes = new Dictionary <string, string>
{
{ "align", columnFormats[i] }
};
}
PushElement(td);
ParseText(columns[i]);
PopElement(); // Pop the th off the stack, adding it to the tr
}
PopElement(); // Pop the tr, adding it to the table
return(true);
}
return(false);
}
