org.daisy.pipeline.css.sass.impl.SassAnalyzer Maven / Gradle / Ivy
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package org.daisy.pipeline.css.sass.impl;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.UncheckedIOException;
import java.net.URI;
import java.net.URL;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.Source;
import javax.xml.transform.TransformerException;
import javax.xml.transform.URIResolver;
import javax.xml.transform.sax.SAXSource;
import javax.xml.transform.stream.StreamSource;
import com.google.common.collect.Iterables;
import com.google.common.io.CharStreams;
import cz.vutbr.web.css.NetworkProcessor;
import cz.vutbr.web.csskit.DefaultNetworkProcessor;
import cz.vutbr.web.csskit.antlr.CSSSource;
import cz.vutbr.web.csskit.antlr.CSSSourceReader;
import cz.vutbr.web.csskit.antlr.DefaultCSSSourceReader;
import cz.vutbr.web.domassign.GenericTreeWalker;
import cz.vutbr.web.csskit.antlr.CSSSourceReader.CSSInputStream;
import org.antlr.runtime.ANTLRReaderStream;
import org.antlr.runtime.CharStream;
import org.antlr.runtime.CommonTokenStream;
import org.antlr.runtime.RecognitionException;
import org.daisy.common.file.URLs;
import org.daisy.pipeline.css.Medium;
import org.daisy.pipeline.datatypes.DatatypeRegistry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Attr;
import org.w3c.dom.CharacterData;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.traversal.DocumentTraversal;
import org.w3c.dom.traversal.NodeFilter;
import org.w3c.dom.traversal.TreeWalker;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
public class SassAnalyzer {
private static final Logger logger = LoggerFactory.getLogger(SassAnalyzer.class.getName());
private final Collection media;
private final CSSSourceReader cssReader;
final DatatypeRegistry datatypes; // also used in SassDocumentationParser
public SassAnalyzer(Collection media, URIResolver uriResolver, DatatypeRegistry datatypes) {
this.media = media;
this.datatypes = datatypes;
NetworkProcessor network = new DefaultNetworkProcessor() {
@Override
public Reader fetch(URL url, Charset encoding, boolean forceEncoding, boolean assertEncoding)
throws IOException {
logger.debug("Fetching style sheet: " + url);
if (uriResolver != null) {
Source resolved; {
try {
resolved = uriResolver.resolve(URLs.asURI(url).toASCIIString(), ""); }
catch (TransformerException e) {
throw new IOException(e); }}
if (resolved != null) {
if (resolved instanceof StreamSource) {
InputStreamReader r = detectEncodingAndSkipBOM(
((StreamSource)resolved).getInputStream(), null, encoding, forceEncoding);
if (assertEncoding) {
if (encoding == null)
throw new IllegalArgumentException("encoding must not be null");
if (!encoding.equals(getEncoding(r)))
throw new IOException("Failed to read URL as " + encoding + ": " + url);
}
return r;
} else {
url = new URL(resolved.getSystemId());
}
}
}
return super.fetch(url, encoding, forceEncoding, assertEncoding);
}
};
cssReader = new DefaultCSSSourceReader(network) {
@Override
public boolean supportsMediaType(String mediaType, URL url) {
if ("text/css".equals(mediaType) || "text/x-scss".equals(mediaType))
return true;
else if (mediaType == null
&& (url == null || url.toString().endsWith(".css") || url.toString().endsWith(".scss")))
return true;
else
return false;
}
// the returned CSSInputStream contains the original (unprocessed) file
@Override
public CSSInputStream read(CSSSource source) throws IOException {
if (source.type == CSSSource.SourceType.URL) {
URL url = (URL)source.source;
if (url != null && !url.toString().endsWith(".css") && !url.toString().endsWith(".scss"))
// check whether the resource exists when ".scss" is added
try {
return read(new CSSSource(new URL(url.toString() + ".scss"), source.encoding, source.mediaType));
} catch (IOException e) {
// ... or ".css" is added
try {
return read(new CSSSource(new URL(url.toString() + ".css"), source.encoding, source.mediaType));
} catch (IOException ee) {
}
// ... or "_" and ".scss" are added
try {
String fileName = url.toString();
fileName = fileName.substring(fileName.lastIndexOf('/') + 1, fileName.length());
return read(new CSSSource(URLs.asURL(URLs.asURI(url).resolve("_" + fileName + ".scss")),
source.encoding,
source.mediaType));
} catch (IOException ee) {
}
// ... or "_index.scss" is added
try {
return read(new CSSSource(new URL(url.toString() + "/_index.scss"), source.encoding, source.mediaType));
} catch (IOException ee) {
}
// otherwise fail
throw e;
}
if (uriResolver != null) {
try {
// NetworkProcessor.fetch() also does resolve() but we need an additional resolve() to give
// CSSInputStream the correct base URL
Source resolved = uriResolver.resolve(URLs.asURI(url).toASCIIString(), "");
if (resolved != null)
source = new CSSSource(new URL(resolved.getSystemId()), source.encoding, source.mediaType);
} catch (TransformerException e) {
throw new IOException(e);
}
}
}
return super.read(source);
}
};
}
public Collection getVariableDeclarations(Iterable userAndUserAgentStylesheets,
Source sourceDocument)
throws IOException {
List stylesheets = new ArrayList<>();
for (Source s : userAndUserAgentStylesheets) {
URL base; {
String systemId = s.getSystemId();
if (systemId == null || "".equals(systemId))
base = null;
else {
URI baseURI = URLs.asURI(systemId);
if (isOpaque(baseURI) || !baseURI.isAbsolute())
throw new IllegalArgumentException("not an absolute hierarchical base URI: " + baseURI);
base = URLs.asURL(baseURI);
}
}
if (s instanceof StreamSource) {
StreamSource ss = (StreamSource)s;
Reader r = ss.getReader();
if (r == null)
r = new InputStreamReader(ss.getInputStream(), StandardCharsets.UTF_8);
stylesheets.add(new CSSSource(CharStreams.toString(r), null, base, 0, 0));
} else {
if (base == null) {
InputSource is = SAXSource.sourceToInputSource(s);
if (is == null)
throw new IllegalArgumentException("unexpected source");
Reader r = is.getCharacterStream();
if (r == null) {
InputStream bs = is.getByteStream();
if (bs != null)
r = new InputStreamReader(bs, StandardCharsets.UTF_8);
else
throw new IllegalArgumentException("unexpected source: no content and no base URI");
}
stylesheets.add(new CSSSource(CharStreams.toString(r), null, base, 0, 0));
} else
stylesheets.add(new CSSSource(base, StandardCharsets.UTF_8, null));
}
}
if (sourceDocument != null) {
try {
Document doc;
URL base; {
if (sourceDocument instanceof DOMSource && ((DOMSource)sourceDocument).getNode() instanceof Document) {
doc = (Document)((DOMSource)sourceDocument).getNode();
URI baseURI = URLs.asURI(doc.getBaseURI());
if (isOpaque(baseURI) || !baseURI.isAbsolute())
throw new IllegalArgumentException("not an absolute hierarchical base URI: " + baseURI);
base = URLs.asURL(baseURI);
} else {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
doc = factory.newDocumentBuilder().parse(SAXSource.sourceToInputSource(sourceDocument));
String systemId = sourceDocument.getSystemId();
if (systemId == null || "".equals(systemId))
base = null;
else {
URI baseURI = URLs.asURI(systemId);
if (isOpaque(baseURI) || !baseURI.isAbsolute())
throw new IllegalArgumentException("not an absolute hierarchical base URI: " + baseURI);
base = URLs.asURL(baseURI);
}
}
}
new Traversal(doc) {
@Override
protected void processElement(Element e) {
if ("style".equalsIgnoreCase(e.getNodeName())) {
Attr q = e.getAttributeNode("media");
if (Iterables.any(media, m -> m.matches(q != null ? q.getValue() : null))) {
Attr type = e.getAttributeNode("type");
String mediaType = type != null ? type.getValue().toLowerCase() : null;
if (cssReader.supportsMediaType(mediaType, null))
stylesheets.add(new CSSSource(extractElementText(e), mediaType, base, -1, -1));
}
} else if ("link".equalsIgnoreCase(e.getNodeName())) {
Attr rel = e.getAttributeNode("rel");
if (rel != null && rel.getValue().toLowerCase().contains("stylesheet")) {
Attr href = e.getAttributeNode("href");
if (href != null) {
Attr q = e.getAttributeNode("media");
if (Iterables.any(media, m -> m.matches(q != null ? q.getValue() : null))) {
URL url; {
try {
URI uri = URLs.asURI(href.getValue());
if (base != null)
uri = URLs.resolve(URLs.asURI(base), uri);
url = URLs.asURL(uri);
} catch (RuntimeException ex) {
throw new UncheckedIOException(new IOException(ex));
}
}
Attr type = e.getAttributeNode("type");
String mediaType = type != null ? type.getValue().toLowerCase() : null;
if (cssReader.supportsMediaType(mediaType, url))
stylesheets.add(new CSSSource(url, null, mediaType));
}
}
}
}
}
}.traverse();
} catch (UncheckedIOException e) {
throw e.getCause();
} catch (SAXException|ParserConfigurationException e) {
throw new IOException(e);
}
}
return getVariableDeclarations(stylesheets.toArray(new CSSSource[stylesheets.size()]));
}
Collection getVariableDeclarations(CSSSource... stylesheets) throws IOException {
List vars = new ArrayList<>();
try {
for (CSSSource source : stylesheets) {
CSSInputStream s = cssReader.read(source);
CharStream input = new ANTLRReaderStream(s.stream);
SassDocumentationLexer lexer = new SassDocumentationLexer(input);
CommonTokenStream tokens = new CommonTokenStream(lexer);
SassDocumentationParser parser = new SassDocumentationParser(tokens).init(
"text/x-scss".equals(source.mediaType) || (s.base != null && s.base.toString().endsWith(".scss")),
s.base != null ? URLs.asURI(s.base) : null,
media,
this);
vars.addAll(parser.variables());
}
} catch (RecognitionException e) {
throw new RuntimeException("Error happened while parsing the SCSS", e);
}
// drop duplicates
Set unique = new TreeSet<>(Comparator.comparing(SassVariable::getName));
Iterator i = vars.iterator();
while (i.hasNext()) {
SassVariable v = i.next();
if (!v.isDefault())
if (!unique.add(v))
i.remove(); }
i = vars.iterator();
while (i.hasNext()) {
SassVariable v = i.next();
if (v.isDefault())
if (!unique.add(v))
i.remove(); }
return vars;
}
private static abstract class Traversal {
private final TreeWalker walker;
protected Traversal(Document doc) {
if (doc instanceof DocumentTraversal)
walker = ((DocumentTraversal)doc).createTreeWalker(doc.getDocumentElement(), NodeFilter.SHOW_ELEMENT, null, false);
else
walker = new GenericTreeWalker(doc.getDocumentElement(), NodeFilter.SHOW_ELEMENT);
}
protected abstract void processElement(Element element);
public void traverse() {
Node current, checkpoint = null;
current = walker.getCurrentNode();
while (current != null) {
checkpoint = walker.getCurrentNode();
processElement((Element)current);
walker.setCurrentNode(checkpoint);
current = walker.nextNode();
}
}
}
private static String extractElementText(Element e) {
StringBuilder s = new StringBuilder();
NodeList children = e.getChildNodes();
for (int i = 0; i < children.getLength(); i++) {
Node child = children.item(i);
if (child.getNodeType() == Node.TEXT_NODE || child.getNodeType() == Node.CDATA_SECTION_NODE)
s.append(((CharacterData)child).getData());
else if (child.getNodeType() == Node.COMMENT_NODE)
s.append("");
}
return s.toString();
}
private static boolean isOpaque(URI uri) {
if (uri.toString().startsWith("jar:file:"))
return uri.isAbsolute() && !uri.getSchemeSpecificPart().substring(5).startsWith("/");
else
return uri.isOpaque();
}
}