package org.jsoup.parser;
import org.jsoup.helper.DescendableLinkedList;
import org.jsoup.helper.StringUtil;
import org.jsoup.helper.Validate;
import org.jsoup.nodes.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
/**
* HTML Tree Builder; creates a DOM from Tokens.
*/
class TreeBuilder {
CharacterReader reader;
Tokeniser tokeniser;
private TreeBuilderState state; // the current state
private TreeBuilderState originalState; // original / marked state
private Document doc; // current doc we are building into
private DescendableLinkedList<Element> stack; // the stack of open elements
private String baseUri; // current base uri, for creating new elements
private Token currentToken; // currentToken is used only for error tracking.
private Element headElement; // the current head element
private Element formElement; // the current form element
private Element contextElement; // fragment parse context -- could be null even if fragment parsing
private DescendableLinkedList<Element> formattingElements = new DescendableLinkedList<Element>(); // active (open) formatting elements
private List<Token.Character> pendingTableCharacters = new ArrayList<Token.Character>(); // chars in table to be shifted out
private boolean framesetOk = true; // if ok to go into frameset
private boolean fosterInserts = false; // if next inserts should be fostered
private boolean fragmentParsing = false; // if parsing a fragment of html
private boolean trackErrors = false;
private List<ParseError> errors = new ArrayList<ParseError>();
TreeBuilder() {}
private void initialiseParse(String input, String baseUri) {
doc = new Document(baseUri);
reader = new CharacterReader(input);
tokeniser = new Tokeniser(reader);
stack = new DescendableLinkedList<Element>();
this.baseUri = baseUri;
}
Document parse(String input, String baseUri) {
state = TreeBuilderState.Initial;
initialiseParse(input, baseUri);
runParser();
return doc;
}
List<Node> parseFragment(String inputFragment, Element context, String baseUri) {
// context may be null
initialiseParse(inputFragment, baseUri);
contextElement = context;
fragmentParsing = true;
Element root = null;
if (context != null) {
if (context.ownerDocument() != null) // quirks setup:
doc.quirksMode(context.ownerDocument().quirksMode());
// initialise the tokeniser state:
String contextTag = context.tagName();
if (StringUtil.in(contextTag, "title", "textarea"))
tokeniser.transition(TokeniserState.Rcdata);
else if (StringUtil.in(contextTag, "iframe", "noembed", "noframes", "style", "xmp"))
tokeniser.transition(TokeniserState.Rawtext);
else if (contextTag.equals("script"))
tokeniser.transition(TokeniserState.ScriptData);
else if (contextTag.equals(("noscript")))
tokeniser.transition(TokeniserState.Data); // if scripting enabled, rawtext
else if (contextTag.equals("plaintext"))
tokeniser.transition(TokeniserState.Data);
else
tokeniser.transition(TokeniserState.Data); // default
root = new Element(Tag.valueOf("html"), baseUri);
doc.appendChild(root);
stack.push(root);
resetInsertionMode();
// todo: setup form element to nearest form on context (up ancestor chain)
}
runParser();
if (context != null)
return root.childNodes();
else
return doc.childNodes();
}
private void runParser() {
while (true) {
// todo: handle foreign content checks
Token token = tokeniser.read();
process(token);
if (token.type == Token.TokenType.EOF)
break;
}
}
boolean process(Token token) {
currentToken = token;
return this.state.process(token, this);
}
boolean process(Token token, TreeBuilderState state) {
currentToken = token;
return state.process(token, this);
}
void transition(TreeBuilderState state) {
this.state = state;
}
TreeBuilderState state() {
return state;
}
void markInsertionMode() {
originalState = state;
}
TreeBuilderState originalState() {
return originalState;
}
void framesetOk(boolean framesetOk) {
this.framesetOk = framesetOk;
}
boolean framesetOk() {
return framesetOk;
}
Element currentElement() {
return stack.getLast();
}
Document getDocument() {
return doc;
}
String getBaseUri() {
return baseUri;
}
void setBaseUri(Element base) {
String href = base.absUrl("href");
if (href.length() != 0) { // ignore <base target> etc
baseUri = href;
doc.setBaseUri(href); // set on the doc so doc.createElement(Tag) will get updated base
}
}
boolean isFragmentParsing() {
return fragmentParsing;
}
void error(TreeBuilderState state) {
if (trackErrors)
errors.add(new ParseError("Unexpected token", state, currentToken, reader.pos()));
}
Element insert(Token.StartTag startTag) {
// handle empty unknown tags
// when the spec expects an empty tag, will directly hit insertEmpty, so won't generate fake end tag.
if (startTag.isSelfClosing() && !Tag.isKnownTag(startTag.name())) {
Element el = insertEmpty(startTag);
process(new Token.EndTag(el.tagName())); // ensure we get out of whatever state we are in
return el;
}
Element el = new Element(Tag.valueOf(startTag.name()), baseUri, startTag.attributes);
insert(el);
return el;
}
Element insert(String startTagName) {
Element el = new Element(Tag.valueOf(startTagName), baseUri);
insert(el);
return el;
}
void insert(Element el) {
insertNode(el);
stack.add(el);
}
Element insertEmpty(Token.StartTag startTag) {
Tag tag = Tag.valueOf(startTag.name());
Element el = new Element(tag, baseUri, startTag.attributes);
insertNode(el);
if (startTag.isSelfClosing()) {
tokeniser.acknowledgeSelfClosingFlag();
if (!tag.isKnownTag()) // unknown tag, remember this is self closing for output
tag.setSelfClosing();
}
return el;
}
void insert(Token.Comment commentToken) {
Comment comment = new Comment(commentToken.getData(), baseUri);
insertNode(comment);
}
void insert(Token.Character characterToken) {
Node node;
// characters in script and style go in as datanodes, not text nodes
if (StringUtil.in(currentElement().tagName(), "script", "style"))
node = new DataNode(characterToken.getData(), baseUri);
else
node = new TextNode(characterToken.getData(), baseUri);
currentElement().appendChild(node); // doesn't use insertNode, because we don't foster these; and will always have a stack.
}
private void insertNode(Node node) {
// if the stack hasn't been set up yet, elements (doctype, comments) go into the doc
if (stack.size() == 0)
doc.appendChild(node);
else if (isFosterInserts())
insertInFosterParent(node);
else
currentElement().appendChild(node);
}
Element pop() {
// todo - dev, remove validation check
if (stack.peekLast().nodeName().equals("td") && !state.name().equals("InCell"))
Validate.isFalse(true, "pop td not in cell");
if (stack.peekLast().nodeName().equals("html"))
Validate.isFalse(true, "popping html!");
return stack.pollLast();
}
void push(Element element) {
stack.add(element);
}
DescendableLinkedList<Element> getStack() {
return stack;
}
boolean onStack(Element el) {
return isElementInQueue(stack, el);
}
private boolean isElementInQueue(DescendableLinkedList<Element> queue, Element element) {
Iterator<Element> it = queue.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next == element) {
return true;
}
}
return false;
}
Element getFromStack(String elName) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next.nodeName().equals(elName)) {
return next;
}
}
return null;
}
boolean removeFromStack(Element el) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next == el) {
it.remove();
return true;
}
}
return false;
}
void popStackToClose(String elName) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next.nodeName().equals(elName)) {
it.remove();
break;
} else {
it.remove();
}
}
}
void popStackToClose(String... elNames) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (StringUtil.in(next.nodeName(), elNames)) {
it.remove();
break;
} else {
it.remove();
}
}
}
void popStackToBefore(String elName) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next.nodeName().equals(elName)) {
break;
} else {
it.remove();
}
}
}
void clearStackToTableContext() {
clearStackToContext("table");
}
void clearStackToTableBodyContext() {
clearStackToContext("tbody", "tfoot", "thead");
}
void clearStackToTableRowContext() {
clearStackToContext("tr");
}
private void clearStackToContext(String... nodeNames) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (StringUtil.in(next.nodeName(), nodeNames) || next.nodeName().equals("html"))
break;
else
it.remove();
}
}
Element aboveOnStack(Element el) {
assert onStack(el);
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next == el) {
return it.next();
}
}
return null;
}
void insertOnStackAfter(Element after, Element in) {
int i = stack.lastIndexOf(after);
Validate.isTrue(i != -1);
stack.add(i+1, in);
}
void replaceOnStack(Element out, Element in) {
replaceInQueue(stack, out, in);
}
private void replaceInQueue(LinkedList<Element> queue, Element out, Element in) {
int i = queue.lastIndexOf(out);
Validate.isTrue(i != -1);
queue.remove(i);
queue.add(i, in);
}
void resetInsertionMode() {
boolean last = false;
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element node = it.next();
if (!it.hasNext()) {
last = true;
node = contextElement;
}
String name = node.nodeName();
if ("select".equals(name)) {
transition(TreeBuilderState.InSelect);
break; // frag
} else if (("td".equals(name) || "td".equals(name) && !last)) {
transition(TreeBuilderState.InCell);
break;
} else if ("tr".equals(name)) {
transition(TreeBuilderState.InRow);
break;
} else if ("tbody".equals(name) || "thead".equals(name) || "tfoot".equals(name)) {
transition(TreeBuilderState.InTableBody);
break;
} else if ("caption".equals(name)) {
transition(TreeBuilderState.InCaption);
break;
} else if ("colgroup".equals(name)) {
transition(TreeBuilderState.InColumnGroup);
break; // frag
} else if ("table".equals(name)) {
transition(TreeBuilderState.InTable);
break;
} else if ("head".equals(name)) {
transition(TreeBuilderState.InBody);
break; // frag
} else if ("body".equals(name)) {
transition(TreeBuilderState.InBody);
break;
} else if ("frameset".equals(name)) {
transition(TreeBuilderState.InFrameset);
break; // frag
} else if ("html".equals(name)) {
transition(TreeBuilderState.BeforeHead);
break; // frag
} else if (last) {
transition(TreeBuilderState.InBody);
break; // frag
}
}
}
// todo: tidy up in specific scope methods
private boolean inSpecificScope(String targetName, String[] baseTypes, String[] extraTypes) {
return inSpecificScope(new String[]{targetName}, baseTypes, extraTypes);
}
private boolean inSpecificScope(String[] targetNames, String[] baseTypes, String[] extraTypes) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element el = it.next();
String elName = el.nodeName();
if (StringUtil.in(elName, targetNames))
return true;
if (StringUtil.in(elName, baseTypes))
return false;
if (extraTypes != null && StringUtil.in(elName, extraTypes))
return false;
}
Validate.fail("Should not be reachable");
return false;
}
boolean inScope(String[] targetNames) {
return inSpecificScope(targetNames, new String[]{"applet", "caption", "html", "table", "td", "th", "marquee", "object"}, null);
}
boolean inScope(String targetName) {
return inScope(targetName, null);
}
boolean inScope(String targetName, String[] extras) {
return inSpecificScope(targetName, new String[]{"applet", "caption", "html", "table", "td", "th", "marquee", "object"}, extras);
// todo: in mathml namespace: mi, mo, mn, ms, mtext annotation-xml
// todo: in svg namespace: forignOjbect, desc, title
}
boolean inListItemScope(String targetName) {
return inScope(targetName, new String[]{"ol", "ul"});
}
boolean inButtonScope(String targetName) {
return inScope(targetName, new String[]{"button"});
}
boolean inTableScope(String targetName) {
return inSpecificScope(targetName, new String[]{"html", "table"}, null);
}
boolean inSelectScope(String targetName) {
Iterator<Element> it = stack.descendingIterator();
while (it.hasNext()) {
Element el = it.next();
String elName = el.nodeName();
if (elName.equals(targetName))
return true;
if (!StringUtil.in(elName, "optgroup", "option")) // all elements except
return false;
}
Validate.fail("Should not be reachable");
return false;
}
void setHeadElement(Element headElement) {
this.headElement = headElement;
}
Element getHeadElement() {
return headElement;
}
boolean isFosterInserts() {
return fosterInserts;
}
void setFosterInserts(boolean fosterInserts) {
this.fosterInserts = fosterInserts;
}
Element getFormElement() {
return formElement;
}
void setFormElement(Element formElement) {
this.formElement = formElement;
}
void newPendingTableCharacters() {
pendingTableCharacters = new ArrayList<Token.Character>();
}
List<Token.Character> getPendingTableCharacters() {
return pendingTableCharacters;
}
void setPendingTableCharacters(List<Token.Character> pendingTableCharacters) {
this.pendingTableCharacters = pendingTableCharacters;
}
/**
11.2.5.2 Closing elements that have implied end tags<p/>
When the steps below require the UA to generate implied end tags, then, while the current node is a dd element, a
dt element, an li element, an option element, an optgroup element, a p element, an rp element, or an rt element,
the UA must pop the current node off the stack of open elements.
@param excludeTag If a step requires the UA to generate implied end tags but lists an element to exclude from the
process, then the UA must perform the above steps as if that element was not in the above list.
*/
void generateImpliedEndTags(String excludeTag) {
while ((excludeTag != null && !currentElement().nodeName().equals(excludeTag)) &&
StringUtil.in(currentElement().nodeName(), "dd", "dt", "li", "option", "optgroup", "p", "rp", "rt"))
pop();
}
void generateImpliedEndTags() {
generateImpliedEndTags(null);
}
boolean isSpecial(Element el) {
// todo: mathml's mi, mo, mn
// todo: svg's foreigObject, desc, title
String name = el.nodeName();
return StringUtil.in(name, "address", "applet", "area", "article", "aside", "base", "basefont", "bgsound",
"blockquote", "body", "br", "button", "caption", "center", "col", "colgroup", "command", "dd",
"details", "dir", "div", "dl", "dt", "embed", "fieldset", "figcaption", "figure", "footer", "form",
"frame", "frameset", "h1", "h2", "h3", "h4", "h5", "h6", "head", "header", "hgroup", "hr", "html",
"iframe", "img", "input", "isindex", "li", "link", "listing", "marquee", "menu", "meta", "nav",
"noembed", "noframes", "noscript", "object", "ol", "p", "param", "plaintext", "pre", "script",
"section", "select", "style", "summary", "table", "tbody", "td", "textarea", "tfoot", "th", "thead",
"title", "tr", "ul", "wbr", "xmp");
}
// active formatting elements
void pushActiveFormattingElements(Element in) {
int numSeen = 0;
Iterator<Element> iter = formattingElements.descendingIterator();
while (iter.hasNext()) {
Element el = iter.next();
if (el == null) // marker
break;
if (isSameFormattingElement(in, el))
numSeen++;
if (numSeen == 3) {
iter.remove();
break;
}
}
formattingElements.add(in);
}
private boolean isSameFormattingElement(Element a, Element b) {
// same if: same namespace, tag, and attributes. Element.equals only checks tag, might in future check children
return a.nodeName().equals(b.nodeName()) &&
// a.namespace().equals(b.namespace()) &&
a.attributes().equals(b.attributes());
// todo: namespaces
}
void reconstructFormattingElements() {
int size = formattingElements.size();
if (size == 0 || formattingElements.getLast() == null || onStack(formattingElements.getLast()))
return;
Element entry = formattingElements.getLast();
int pos = size - 1;
boolean skip = false;
while (true) {
if (pos == 0) { // step 4. if none before, skip to 8
skip = true;
break;
}
entry = formattingElements.get(--pos); // step 5. one earlier than entry
if (entry == null || onStack(entry)) // step 6 - neither marker nor on stack
break; // jump to 8, else continue back to 4
}
while(true) {
if (!skip) // step 7: on later than entry
entry = formattingElements.get(++pos);
Validate.notNull(entry); // should not occur, as we break at last element
// 8. create new element from element, 9 insert into current node, onto stack
skip = false; // can only skip increment from 4.
Element newEl = insert(entry.nodeName()); // todo: avoid fostering here?
// newEl.namespace(entry.namespace()); // todo: namespaces
newEl.attributes().addAll(entry.attributes());
// 10. replace entry with new entry
formattingElements.add(pos, newEl);
formattingElements.remove(pos + 1);
// 11
if (pos == size-1) // if not last entry in list, jump to 7
break;
}
}
void clearFormattingElementsToLastMarker() {
while (!formattingElements.isEmpty()) {
Element el = formattingElements.peekLast();
formattingElements.removeLast();
if (el == null)
break;
}
}
void removeFromActiveFormattingElements(Element el) {
Iterator<Element> it = formattingElements.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next == el) {
it.remove();
break;
}
}
}
boolean isInActiveFormattingElements(Element el) {
return isElementInQueue(formattingElements, el);
}
Element getActiveFormattingElement(String nodeName) {
Iterator<Element> it = formattingElements.descendingIterator();
while (it.hasNext()) {
Element next = it.next();
if (next == null) // scope marker
break;
else if (next.nodeName().equals(nodeName))
return next;
}
return null;
}
void replaceActiveFormattingElement(Element out, Element in) {
replaceInQueue(formattingElements, out, in);
}
void insertMarkerToFormattingElements() {
formattingElements.add(null);
}
void insertInFosterParent(Node in) {
Element fosterParent = null;
Element lastTable = getFromStack("table");
boolean isLastTableParent = false;
if (lastTable != null) {
if (lastTable.parent() != null) {
fosterParent = lastTable.parent();
isLastTableParent = true;
} else
fosterParent = aboveOnStack(lastTable);
} else { // no table == frag
fosterParent = stack.get(0);
}
if (isLastTableParent) {
Validate.notNull(lastTable); // last table cannot be null by this point.
lastTable.before(in);
}
else
fosterParent.appendChild(in);
}
@Override
public String toString() {
return "TreeBuilder{" +
"currentToken=" + currentToken +
", state=" + state +
", currentElement=" + currentElement() +
'}';
}
}
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