gerrit-server/src/main/java/com/google/gerrit/server/documentation/MarkdownFormatter.java - gerrit - Git at Google

 // Copyright (C) 2012 The Android Open Source Project
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 // http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 package com.google.gerrit.server.documentation;

 import static org.pegdown.Extensions.ALL;
 import static org.pegdown.Extensions.HARDWRAPS;

 import com.google.common.base.Strings;

 import org.eclipse.jgit.util.RawParseUtils;
 import org.eclipse.jgit.util.TemporaryBuffer;
 import org.pegdown.LinkRenderer;
 import org.pegdown.PegDownProcessor;
 import org.pegdown.ToHtmlSerializer;
 import org.pegdown.ast.HeaderNode;
 import org.pegdown.ast.Node;
 import org.pegdown.ast.RootNode;
 import org.pegdown.ast.TextNode;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.UnsupportedEncodingException;
 import java.net.URL;
 import java.nio.charset.Charset;
 import java.util.concurrent.atomic.AtomicBoolean;

 public class MarkdownFormatter {
   private static final Logger log =
       LoggerFactory.getLogger(MarkdownFormatter.class);

   private static final String css;

   static {
     AtomicBoolean file = new AtomicBoolean();
     String src;
     try {
       src = readPegdownCss(file);
     } catch (IOException err) {
       log.warn("Cannot load pegdown.css", err);
       src = "";
     }
     css = file.get() ? null : src;
   }

   private static String readCSS() {
     if (css != null) {
       return css;
     }
     try {
       return readPegdownCss(new AtomicBoolean());
     } catch (IOException err) {
       log.warn("Cannot load pegdown.css", err);
       return "";
     }
   }

   public byte[] markdownToDocHtml(String md, String charEnc)
       throws UnsupportedEncodingException {
     RootNode root = parseMarkdown(md);
     String title = findTitle(root);

     StringBuilder html = new StringBuilder();
     html.append("<html>");
     html.append("<head>");
     if (!Strings.isNullOrEmpty(title)) {
       html.append("<title>").append(title).append("</title>");
     }
     html.append("<style type=\"text/css\">\n")
         .append(readCSS())
         .append("\n</style>");
     html.append("</head>");
     html.append("<body>\n");
     html.append(new ToHtmlSerializer(new LinkRenderer()).toHtml(root));
     html.append("\n</body></html>");
     return html.toString().getBytes(charEnc);
   }

   public String extractTitleFromMarkdown(byte[] data, String charEnc) {
     String md = RawParseUtils.decode(Charset.forName(charEnc), data);
     return findTitle(parseMarkdown(md));
   }

   private String findTitle(Node root) {
     if (root instanceof HeaderNode) {
       HeaderNode h = (HeaderNode) root;
       if (h.getLevel() == 1
           && h.getChildren() != null
           && !h.getChildren().isEmpty()) {
         StringBuilder b = new StringBuilder();
         for (Node n : root.getChildren()) {
           if (n instanceof TextNode) {
             b.append(((TextNode) n).getText());
           }
         }
         return b.toString();
       }
     }

     for (Node n : root.getChildren()) {
       String title = findTitle(n);
       if (title != null) {
         return title;
       }
     }
     return null;
   }

   private RootNode parseMarkdown(String md) {
     return new PegDownProcessor(ALL & ~(HARDWRAPS))
         .parseMarkdown(md.toCharArray());
   }

   private static String readPegdownCss(AtomicBoolean file)
       throws IOException {
     String name = "pegdown.css";
     URL url = MarkdownFormatter.class.getResource(name);
     if (url == null) {
       throw new FileNotFoundException("Resource " + name);
     }
     file.set("file".equals(url.getProtocol()));
     InputStream in = url.openStream();
     try {
       TemporaryBuffer.Heap tmp = new TemporaryBuffer.Heap(128 * 1024);
       try {
         tmp.copy(in);
         return new String(tmp.toByteArray(), "UTF-8");
       } finally {
         tmp.close();
       }
     } finally {
       in.close();
     }
   }
 }
	// Copyright (C) 2012 The Android Open Source Project
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	package com.google.gerrit.server.documentation;

	import static org.pegdown.Extensions.ALL;
	import static org.pegdown.Extensions.HARDWRAPS;

	import com.google.common.base.Strings;

	import org.eclipse.jgit.util.RawParseUtils;
	import org.eclipse.jgit.util.TemporaryBuffer;
	import org.pegdown.LinkRenderer;
	import org.pegdown.PegDownProcessor;
	import org.pegdown.ToHtmlSerializer;
	import org.pegdown.ast.HeaderNode;
	import org.pegdown.ast.Node;
	import org.pegdown.ast.RootNode;
	import org.pegdown.ast.TextNode;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	import java.io.FileNotFoundException;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.UnsupportedEncodingException;
	import java.net.URL;
	import java.nio.charset.Charset;
	import java.util.concurrent.atomic.AtomicBoolean;

	public class MarkdownFormatter {
	private static final Logger log =
	LoggerFactory.getLogger(MarkdownFormatter.class);

	private static final String css;

	static {
	AtomicBoolean file = new AtomicBoolean();
	String src;
	try {
	src = readPegdownCss(file);
	} catch (IOException err) {
	log.warn("Cannot load pegdown.css", err);
	src = "";
	}
	css = file.get() ? null : src;
	}

	private static String readCSS() {
	if (css != null) {
	return css;
	}
	try {
	return readPegdownCss(new AtomicBoolean());
	} catch (IOException err) {
	log.warn("Cannot load pegdown.css", err);
	return "";
	}
	}

	public byte[] markdownToDocHtml(String md, String charEnc)
	throws UnsupportedEncodingException {
	RootNode root = parseMarkdown(md);
	String title = findTitle(root);

	StringBuilder html = new StringBuilder();
	html.append("<html>");
	html.append("<head>");
	if (!Strings.isNullOrEmpty(title)) {
	html.append("<title>").append(title).append("</title>");
	}
	html.append("<style type=\"text/css\">\n")
	.append(readCSS())
	.append("\n</style>");
	html.append("</head>");
	html.append("<body>\n");
	html.append(new ToHtmlSerializer(new LinkRenderer()).toHtml(root));
	html.append("\n</body></html>");
	return html.toString().getBytes(charEnc);
	}

	public String extractTitleFromMarkdown(byte[] data, String charEnc) {
	String md = RawParseUtils.decode(Charset.forName(charEnc), data);
	return findTitle(parseMarkdown(md));
	}

	private String findTitle(Node root) {
	if (root instanceof HeaderNode) {
	HeaderNode h = (HeaderNode) root;
	if (h.getLevel() == 1
	&& h.getChildren() != null
	&& !h.getChildren().isEmpty()) {
	StringBuilder b = new StringBuilder();
	for (Node n : root.getChildren()) {
	if (n instanceof TextNode) {
	b.append(((TextNode) n).getText());
	}
	}
	return b.toString();
	}
	}

	for (Node n : root.getChildren()) {
	String title = findTitle(n);
	if (title != null) {
	return title;
	}
	}
	return null;
	}

	private RootNode parseMarkdown(String md) {
	return new PegDownProcessor(ALL & ~(HARDWRAPS))
	.parseMarkdown(md.toCharArray());
	}

	private static String readPegdownCss(AtomicBoolean file)
	throws IOException {
	String name = "pegdown.css";
	URL url = MarkdownFormatter.class.getResource(name);
	if (url == null) {
	throw new FileNotFoundException("Resource " + name);
	}
	file.set("file".equals(url.getProtocol()));
	InputStream in = url.openStream();
	try {
	TemporaryBuffer.Heap tmp = new TemporaryBuffer.Heap(128 * 1024);
	try {
	tmp.copy(in);
	return new String(tmp.toByteArray(), "UTF-8");
	} finally {
	tmp.close();
	}
	} finally {
	in.close();
	}
	}
	}