/// <summary>
/// Rearrange the DOM of the box to have block box with boxes before the inner block box and after.
/// </summary>
/// <param name="box">the box that has the problem</param>
private static void CorrectBlockInsideInlineImp(CssBox box)
{
if (box.Boxes.Count > 1)
{
var leftBlock = CssBox.CreateBlock(box);
while (ContainsInlinesOnlyDeep(box.Boxes[0]))
{
box.Boxes[0].ParentBox = leftBlock;
}
leftBlock.SetBeforeBox(box.Boxes[0]);
var splitBox = box.Boxes[1];
splitBox.ParentBox = null;
CorrectBlockSplitBadBox(box, splitBox, leftBlock);
if (box.Boxes.Count > 2)
{
var rightBox = CssBox.CreateBox(box, null, box.Boxes[2]);
while (box.Boxes.Count > 3)
{
box.Boxes[3].ParentBox = rightBox;
}
}
box.Display = CssConstants.Block;
}
else
{
box.Boxes[0].Display = CssConstants.Block;
}
}
/// <summary>
/// Split bad box that has inline and block boxes into two parts, the left - before the block box
/// and right - after the block box.
/// </summary>
/// <param name="parentBox">the parent box that has the problem</param>
/// <param name="badBox">the box to split into different boxes</param>
/// <param name="leftBlock">the left block box that is created for the split</param>
private static void CorrectBlockSplitBadBox(CssBox parentBox, CssBox badBox, CssBox leftBlock)
{
var leftbox = CssBox.CreateBox(leftBlock, badBox.HtmlTag);
leftbox.InheritStyle(badBox, true);
bool hadLeft = false;
while (badBox.Boxes[0].IsInline && ContainsInlinesOnlyDeep(badBox.Boxes[0]))
{
hadLeft = true;
badBox.Boxes[0].ParentBox = leftbox;
}
var splitBox = badBox.Boxes[0];
if (!ContainsInlinesOnlyDeep(splitBox))
{
CorrectBlockSplitBadBox(parentBox, splitBox, leftBlock);
splitBox.ParentBox = null;
}
else
{
splitBox.ParentBox = parentBox;
}
if (badBox.Boxes.Count > 0)
{
CssBox rightBox;
if (splitBox.ParentBox != null || parentBox.Boxes.Count < 2)
{
rightBox = CssBox.CreateBox(parentBox, badBox.HtmlTag);
rightBox.InheritStyle(badBox, true);
if (parentBox.Boxes.Count > 2)
{
rightBox.SetBeforeBox(parentBox.Boxes[1]);
}
splitBox.SetBeforeBox(rightBox);
}
else
{
rightBox = parentBox.Boxes[2];
}
while (badBox.Boxes.Count > 0)
{
badBox.Boxes[0].ParentBox = rightBox;
}
}
else if (splitBox.ParentBox != null && parentBox.Boxes.Count > 1)
{
splitBox.SetBeforeBox(parentBox.Boxes[1]);
if (splitBox.HtmlTag != null && splitBox.HtmlTag.Name == "br" && (hadLeft || leftBlock.Boxes.Count > 1))
{
splitBox.Display = CssConstants.Inline;
}
}
}
/// <summary>
/// Add html text anon box to the current box, this box will have the rendered text<br/>
/// Adding box also for text that contains only whitespaces because we don't know yet if
/// the box is preformatted. At later stage they will be removed if not relevant.
/// </summary>
/// <param name="source">the html source to parse</param>
/// <param name="startIdx">the start of the html part</param>
/// <param name="tagIdx">the index of the next html tag</param>
/// <param name="curBox">the current box in html tree parsing</param>
private static void AddTextBox(string source, int startIdx, int tagIdx, ref CssBox curBox)
{
var text = tagIdx > startIdx ? new SubString(source, startIdx, tagIdx - startIdx) : null;
if (text != null)
{
var abox = CssBox.CreateBox(curBox);
abox.Text = text;
}
}
/// <summary>
/// Rearrange the DOM of the box to have block box with boxes before the inner block box and after.
/// </summary>
/// <param name="box">the box that has the problem</param>
private static CssBox CorrectBlockInsideInlineImp(CssBox box)
{
if (box.Display == CssConstants.Inline)
{
box.Display = CssConstants.Block;
}
if (box.Boxes.Count > 1 || box.Boxes[0].Boxes.Count > 1)
{
var leftBlock = CssBox.CreateBlock(box);
while (ContainsInlinesOnlyDeep(box.Boxes[0]))
{
box.Boxes[0].ParentBox = leftBlock;
}
leftBlock.SetBeforeBox(box.Boxes[0]);
var splitBox = box.Boxes[1];
splitBox.ParentBox = null;
CorrectBlockSplitBadBox(box, splitBox, leftBlock);
// remove block that did not get any inner elements
if (leftBlock.Boxes.Count < 1)
{
leftBlock.ParentBox = null;
}
int minBoxes = leftBlock.ParentBox != null ? 2 : 1;
if (box.Boxes.Count > minBoxes)
{
// create temp box to handle the tail elements and then get them back so no deep hierarchy is created
var tempRightBox = CssBox.CreateBox(box, null, box.Boxes[minBoxes]);
while (box.Boxes.Count > minBoxes + 1)
{
box.Boxes[minBoxes + 1].ParentBox = tempRightBox;
}
return(tempRightBox);
}
}
else if (box.Boxes[0].Display == CssConstants.Inline)
{
box.Boxes[0].Display = CssConstants.Block;
}
return(null);
}
/// <summary>
/// Parses the source html to css boxes tree structure.
/// </summary>
/// <param name="source">the html source to parse</param>
public static CssBox ParseDocument(string source)
{
var root = CssBox.CreateBlock();
var curBox = root;
int endIdx = 0;
int startIdx = 0;
while (startIdx >= 0)
{
var tagIdx = source.IndexOf('<', startIdx);
if (tagIdx >= 0 && tagIdx < source.Length)
{
// add the html text as anon css box to the structure
AddTextBox(source, startIdx, tagIdx, ref curBox);
if (source[tagIdx + 1] == '!')
{
// skip the html crap elements (<!-- bla -->) (<!crap bla>)
startIdx = source.IndexOf(">", tagIdx + 2);
endIdx = startIdx > 0 ? startIdx + 1 : tagIdx + 2;
}
else
{
// parse element tag to css box structure
endIdx = ParseHtmlTag(source, tagIdx, ref curBox) + 1;
}
}
startIdx = tagIdx > -1 && endIdx > 0 ? endIdx : -1;
}
// handle pices of html without proper structure
if (endIdx < source.Length)
{
// there is text after the end of last element
var endText = new SubString(source, endIdx, source.Length - endIdx);
if (!endText.IsEmptyOrWhitespace())
{
var abox = CssBox.CreateBox(root);
abox.Text = endText;
}
}
return(root);
}
/// <summary>
/// Parse the html part, the part from prev parsing index to the beginning of the next html tag.<br/>
/// </summary>
/// <param name="source">the html source to parse</param>
/// <param name="tagIdx">the index of the next html tag</param>
/// <param name="curBox">the current box in html tree parsing</param>
/// <returns>the end of the parsed part, the new start index</returns>
private static int ParseHtmlTag(string source, int tagIdx, ref CssBox curBox)
{
var endIdx = source.IndexOf('>', tagIdx + 1);
if (endIdx > 0)
{
string tagName;
Dictionary <string, string> tagAttributes;
var length = endIdx - tagIdx + 1 - (source[endIdx - 1] == '/' ? 1 : 0);
if (ParseHtmlTag(source, tagIdx, length, out tagName, out tagAttributes))
{
if (!HtmlUtils.IsSingleTag(tagName) && curBox.ParentBox != null)
{
// need to find the parent tag to go one level up
curBox = DomUtils.FindParent(curBox.ParentBox, tagName, curBox);
}
}
else if (!string.IsNullOrEmpty(tagName))
{
//new SubString(source, lastEnd + 1, tagmatch.Index - lastEnd - 1)
var isSingle = HtmlUtils.IsSingleTag(tagName) || source[endIdx - 1] == '/';
var tag = new HtmlTag(tagName, isSingle, tagAttributes);
if (isSingle)
{
// the current box is not changed
CssBox.CreateBox(tag, curBox);
}
else
{
// go one level down, make the new box the current box
curBox = CssBox.CreateBox(tag, curBox);
}
}
else
{
endIdx = tagIdx + 1;
}
}
return(endIdx);
}
/// <summary>
/// Parses the source html to css boxes tree structure.
/// </summary>
/// <param name="source">the html source to parse</param>
public static CssBox ParseDocument(string source)
{
var root = CssBox.CreateBlock();
var curBox = root;
int endIdx = 0;
int startIdx = 0;
while (startIdx >= 0)
{
var tagIdx = source.IndexOf('<', startIdx);
if (tagIdx >= 0 && tagIdx < source.Length)
{
// add the html text as anon css box to the structure
AddTextBox(source, startIdx, tagIdx, ref curBox);
if (source[tagIdx + 1] == '!')
{
if (source[tagIdx + 2] == '-')
{
// skip the html comment elements (<!-- bla -->)
startIdx = source.IndexOf("-->", tagIdx + 2);
endIdx = startIdx > 0 ? startIdx + 3 : tagIdx + 2;
}
else
{
// skip the html crap elements (<!crap bla>)
startIdx = source.IndexOf(">", tagIdx + 2);
endIdx = startIdx > 0 ? startIdx + 1 : tagIdx + 2;
}
}
else
{
// parse element tag to css box structure
endIdx = ParseHtmlTag(source, tagIdx, ref curBox) + 1;
if (curBox.HtmlTag != null &&
curBox.HtmlTag.Name.Equals(HtmlConstants.Style, StringComparison.OrdinalIgnoreCase))
{
var endIdxS = endIdx;
endIdx = source.IndexOf("</style>", endIdx, StringComparison.OrdinalIgnoreCase);
if (endIdx > -1)
{
AddTextBox(source, endIdxS, endIdx, ref curBox);
}
}
}
}
startIdx = tagIdx > -1 && endIdx > 0 ? endIdx : -1;
}
// handle pieces of html without proper structure
if (endIdx > -1 && endIdx < source.Length)
{
// there is text after the end of last element
var endText = new SubString(source, endIdx, source.Length - endIdx);
if (!endText.IsEmptyOrWhitespace())
{
var abox = CssBox.CreateBox(root);
abox.Text = endText;
}
}
return(root);
}
/// <summary>
/// Split bad box that has inline and block boxes into two parts, the left - before the block box
/// and right - after the block box.
/// </summary>
/// <param name="parentBox">the parent box that has the problem</param>
/// <param name="badBox">the box to split into different boxes</param>
/// <param name="leftBlock">the left block box that is created for the split</param>
private static void CorrectBlockSplitBadBox(CssBox parentBox, CssBox badBox, CssBox leftBlock)
{
CssBox leftbox = null;
while (badBox.Boxes[0].IsInline && ContainsInlinesOnlyDeep(badBox.Boxes[0]))
{
if (leftbox == null)
{
// if there is no elements in the left box there is no reason to keep it
leftbox = CssBox.CreateBox(leftBlock, badBox.HtmlTag);
leftbox.InheritStyle(badBox, true);
}
badBox.Boxes[0].ParentBox = leftbox;
}
var splitBox = badBox.Boxes[0];
if (!ContainsInlinesOnlyDeep(splitBox))
{
CorrectBlockSplitBadBox(parentBox, splitBox, leftBlock);
splitBox.ParentBox = null;
}
else
{
splitBox.ParentBox = parentBox;
}
if (badBox.Boxes.Count > 0)
{
CssBox rightBox;
if (splitBox.ParentBox != null || parentBox.Boxes.Count < 3)
{
rightBox = CssBox.CreateBox(parentBox, badBox.HtmlTag);
rightBox.InheritStyle(badBox, true);
if (parentBox.Boxes.Count > 2)
{
rightBox.SetBeforeBox(parentBox.Boxes[1]);
}
if (splitBox.ParentBox != null)
{
splitBox.SetBeforeBox(rightBox);
}
}
else
{
rightBox = parentBox.Boxes[2];
}
rightBox.SetAllBoxes(badBox);
}
else if (splitBox.ParentBox != null && parentBox.Boxes.Count > 1)
{
splitBox.SetBeforeBox(parentBox.Boxes[1]);
if (splitBox.HtmlTag != null && splitBox.HtmlTag.Name == "br" && (leftbox != null || leftBlock.Boxes.Count > 1))
{
splitBox.Display = CssConstants.Inline;
}
}
}
/// <summary>
/// Split bad box that has inline and block boxes into two parts, the left - before the block box
/// and right - after the block box.
/// </summary>
/// <param name="parentBox">the parent box that has the problem</param>
/// <param name="badBox">the box to split into different boxes</param>
/// <param name="leftBlock">the left block box that is created for the split</param>
private static void CorrectBlockSplitBadBox(CssBox parentBox, CssBox badBox, CssBox leftBlock)
{
CssBox leftbox = null;
//This checks if the first child of badbox isInline and if it has only inline elements
while (badBox.Boxes[0].IsInline && ContainsInlinesOnlyDeep(badBox.Boxes[0]))
{
if (leftbox == null)
{
// if there is no elements in the left box there is no reason to keep it
leftbox = CssBox.CreateBox(leftBlock, badBox.HtmlTag);
leftbox.InheritStyle(badBox, true);
}
//puts the HTML of leftbox (which is a new box?) into the parent ofbadbox (it's previous parent)
badBox.Boxes[0].ParentBox = leftbox;
}
var splitBox = badBox.Boxes[0];
if (!ContainsInlinesOnlyDeep(splitBox))
{
CorrectBlockSplitBadBox(parentBox, splitBox, leftBlock);
splitBox.ParentBox = null;
}
else
{
splitBox.ParentBox = parentBox;
}
if (badBox.Boxes.Count > 0)
{
CssBox rightBox;
if (splitBox.ParentBox != null || parentBox.Boxes.Count < 3)
{
rightBox = CssBox.CreateBox(parentBox, badBox.HtmlTag);
rightBox.InheritStyle(badBox, true);
if (parentBox.Boxes.Count > 2)
{
rightBox.SetBeforeBox(parentBox.Boxes[1]);
}
if (splitBox.ParentBox != null)
{
splitBox.SetBeforeBox(rightBox);
}
}
else
{
rightBox = parentBox.Boxes[2];
}
rightBox.SetAllBoxes(badBox);
}
else if (splitBox.ParentBox != null && parentBox.Boxes.Count > 1)
{
splitBox.SetBeforeBox(parentBox.Boxes[1]);
if (splitBox.HtmlTag != null && splitBox.HtmlTag.Name == "br" && (leftbox != null || leftBlock.Boxes.Count > 1))
{
splitBox.Display = CssConstants.Inline;
}
}
}
/// <summary>
/// Parses the document
/// </summary>
public static CssBox ParseDocument(string document)
{
document = RemoveHtmlComments(document);
int lastEnd = -1;
CssBox root = null;
CssBox curBox = null;
var tags = RegexParserUtils.Match(RegexParserUtils.HtmlTag, document);
foreach (Match tagmatch in tags)
{
string text = tagmatch.Index > 0 ? document.Substring(lastEnd + 1, tagmatch.Index - lastEnd - 1) : String.Empty;
var emptyText = String.IsNullOrEmpty(text.Trim());
if (!emptyText)
{
if (curBox == null)
{
root = curBox = CssBox.CreateBlock();
}
var abox = CssBox.CreateBox(curBox);
abox.Text = text;
}
var tag = ParseHtmlTag(tagmatch.Value);
if (tag.IsClosing)
{
// handle tags that have no content but whitespace
if (emptyText && curBox != null && curBox.Boxes.Count == 0 && !string.IsNullOrEmpty(text))
{
var abox = CssBox.CreateBox(curBox);
abox.Text = " ";
}
// need to find the parent tag to go one level up
curBox = DomUtils.FindParent(root, tag.Name, curBox);
}
else if (tag.IsSingle)
{
// the current box is not changed
new CssBox(curBox, tag);
}
else
{
// go one level down, make the new box the current box
curBox = new CssBox(curBox, tag);
}
if (root == null && curBox != null)
{
root = curBox;
root.Display = CssConstants.Block;
}
lastEnd = tagmatch.Index + tagmatch.Length - 1;
}
if (root == null)
{
root = CssBox.CreateBlock();
var abox = CssBox.CreateBox(root);
abox.Text = document;
}
else if (lastEnd < document.Length)
{
var endText = document.Substring(lastEnd + 1);
if (!string.IsNullOrEmpty(endText.Trim()))
{
var abox = CssBox.CreateBox(root);
abox.Text = endText;
}
}
return(root);
}
