/**

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

  *

  * Copyright 2013-2014 Oracle and/or its affiliates. All rights reserved.

  *

  * Oracle and Java are registered trademarks of Oracle and/or its affiliates.

  * Other names may be trademarks of their respective owners.

  *

  * The contents of this file are subject to the terms of either the GNU

  * General Public License Version 2 only ("GPL") or the Common

  * Development and Distribution License("CDDL") (collectively, the

  * "License"). You may not use this file except in compliance with the

  * License. You can obtain a copy of the License at

  * http://www.netbeans.org/cddl-gplv2.html

  * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the

  * specific language governing permissions and limitations under the

  * License.  When distributing the software, include this License Header

  * Notice in each file and include the License file at

  * nbbuild/licenses/CDDL-GPL-2-CP.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the GPL Version 2 section of the License file that

  * accompanied this code. If applicable, add the following below the

  * License Header, with the fields enclosed by brackets [] replaced by

  * your own identifying information:

  * "Portions Copyrighted [year] [name of copyright owner]"

  *

  * Contributor(s):

  *

  * The Original Software is NetBeans. The Initial Developer of the Original

  * Software is Oracle. Portions Copyright 2013-2014 Oracle. All Rights Reserved.

  *

  * If you wish your version of this file to be governed by only the CDDL

  * or only the GPL Version 2, indicate your decision by adding

  * "[Contributor] elects to include this software in this distribution

  * under the [CDDL or GPL Version 2] license." If you do not indicate a

  * single choice of license, a recipient has the option to distribute

  * your version of this file under either the CDDL, the GPL Version 2 or

  * to extend the choice of license to its licensees as provided above.

  * However, if you add GPL Version 2 code and therefore, elected the GPL

  * Version 2 license, then the option applies only if the new code is

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  */

 package net.java.html.json;

 import java.io.ByteArrayInputStream;

 import java.io.ByteArrayOutputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStream;

 import java.net.URI;

 import java.net.URISyntaxException;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Locale;

 import java.util.Map;

 import java.util.regex.Matcher;

 import java.util.regex.Pattern;

 import javax.tools.Diagnostic;

 import javax.tools.DiagnosticListener;

 import javax.tools.FileObject;

 import javax.tools.ForwardingJavaFileManager;

 import javax.tools.JavaFileManager;

 import javax.tools.JavaFileObject;

 import javax.tools.JavaFileObject.Kind;

 import javax.tools.SimpleJavaFileObject;

 import javax.tools.StandardJavaFileManager;

 import javax.tools.StandardLocation;

 import javax.tools.ToolProvider;

 import static org.testng.Assert.assertFalse;

 import static org.testng.Assert.fail;

 /**

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  */

 final class Compile implements DiagnosticListener<JavaFileObject> {

     private final List<Diagnostic<? extends JavaFileObject>> errors = 

             new ArrayList<Diagnostic<? extends JavaFileObject>>();

     private final Map<String, byte[]> classes;

     private final String pkg;

     private final String cls;

     private final String html;

     private final String sourceLevel;

     private Compile(String html, String code, String sl) throws IOException {

         this.pkg = findPkg(code);

         this.cls = findCls(code);

         this.html = html;

         this.sourceLevel = sl;

         classes = compile(html, code);

     }

     /** Performs compilation of given HTML page and associated Java code

      */

     public static Compile create(String html, String code) throws IOException {

         return create(html, code, "1.7");

     }

     static Compile create(String html, String code, String sourceLevel) throws IOException {

         return new Compile(html, code, sourceLevel);

     }

     /** Checks for given class among compiled resources */

     public byte[] get(String res) {

         return classes.get(res);

     }

     /** Obtains errors created during compilation.

      */

     public List<Diagnostic<? extends JavaFileObject>> getErrors() {

         List<Diagnostic<? extends JavaFileObject>> err;

         err = new ArrayList<Diagnostic<? extends JavaFileObject>>();

         for (Diagnostic<? extends JavaFileObject> diagnostic : errors) {

             if (diagnostic.getKind() == Diagnostic.Kind.ERROR) {

                 err.add(diagnostic);

             }

         }

         return err;

     }

     private Map<String, byte[]> compile(final String html, final String code) throws IOException {

         StandardJavaFileManager sjfm = ToolProvider.getSystemJavaCompiler().getStandardFileManager(this, null, null);

         final Map<String, ByteArrayOutputStream> class2BAOS;

         class2BAOS = new HashMap<String, ByteArrayOutputStream>();

         JavaFileObject file = new SimpleJavaFileObject(URI.create("mem://mem"), Kind.SOURCE) {

             @Override

             public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {

                 return code;

             }

         };

         final JavaFileObject htmlFile = new SimpleJavaFileObject(URI.create("mem://mem2"), Kind.OTHER) {

             @Override

             public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {

                 return html;

             }

             @Override

             public InputStream openInputStream() throws IOException {

                 return new ByteArrayInputStream(html.getBytes());

             }

         };

         final URI scratch;

         try {

             scratch = new URI("mem://mem3");

         } catch (URISyntaxException ex) {

             throw new IOException(ex);

         }

         JavaFileManager jfm = new ForwardingJavaFileManager<JavaFileManager>(sjfm) {

             @Override

             public JavaFileObject getJavaFileForOutput(Location location, String className, Kind kind, FileObject sibling) throws IOException {

                 if (kind  == Kind.CLASS) {

                     final ByteArrayOutputStream buffer = new ByteArrayOutputStream();

                     class2BAOS.put(className.replace('.', '/') + ".class", buffer);

                     return new SimpleJavaFileObject(sibling.toUri(), kind) {

                         @Override

                         public OutputStream openOutputStream() throws IOException {

                             return buffer;

                         }

                     };

                 }

                 if (kind == Kind.SOURCE) {

                     final String n = className.replace('.', '/') + ".java";

                     final URI un;

                     try {

                         un = new URI("mem://" + n);

                     } catch (URISyntaxException ex) {

                         throw new IOException(ex);

                     }

                     return new VirtFO(un/*sibling.toUri()*/, kind, n);

                 }

                 throw new IllegalStateException();

             }

             @Override

             public FileObject getFileForInput(Location location, String packageName, String relativeName) throws IOException {

                 if (location == StandardLocation.SOURCE_PATH) {

                     if (packageName.equals(pkg)) {

                         return htmlFile;

                     }

                 }

                 return null;

             }

             @Override

             public boolean isSameFile(FileObject a, FileObject b) {

                 if (a instanceof VirtFO && b instanceof VirtFO) {

                     return ((VirtFO)a).getName().equals(((VirtFO)b).getName());

                 }

                 return super.isSameFile(a, b);

             }

             class VirtFO extends SimpleJavaFileObject {

                 private final String n;

                 public VirtFO(URI uri, Kind kind, String n) {

                     super(uri, kind);

                     this.n = n;

                 }

                 private final ByteArrayOutputStream data = new ByteArrayOutputStream();

                 @Override

                 public OutputStream openOutputStream() throws IOException {

                     return data;

                 }

                 @Override

                 public String getName() {

                     return n;

                 }

                 @Override

                 public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {

                     data.close();

                     return new String(data.toByteArray());

                 }

             }

         };

         ToolProvider.getSystemJavaCompiler().getTask(null, jfm, this, /*XXX:*/Arrays.asList("-source", sourceLevel, "-target", "1.7"), null, Arrays.asList(file)).call();

         Map<String, byte[]> result = new HashMap<String, byte[]>();

         for (Map.Entry<String, ByteArrayOutputStream> e : class2BAOS.entrySet()) {

             result.put(e.getKey(), e.getValue().toByteArray());

         }

         return result;

     }

     @Override

     public void report(Diagnostic<? extends JavaFileObject> diagnostic) {

         errors.add(diagnostic);

     }

     private static String findPkg(String java) throws IOException {

         Pattern p = Pattern.compile("package\\p{javaWhitespace}*([\\p{Alnum}\\.]+)\\p{javaWhitespace}*;", Pattern.MULTILINE);

         Matcher m = p.matcher(java);

         if (!m.find()) {

             throw new IOException("Can't find package declaration in the java file");

         }

         String pkg = m.group(1);

         return pkg;

     }

     private static String findCls(String java) throws IOException {

         Pattern p = Pattern.compile("class\\p{javaWhitespace}*([\\p{Alnum}\\.]+)\\p{javaWhitespace}", Pattern.MULTILINE);

         Matcher m = p.matcher(java);

         if (!m.find()) {

             throw new IOException("Can't find package declaration in the java file");

         }

         String cls = m.group(1);

         return cls;

     }

     String getHtml() {

         String fqn = "'" + pkg + '.' + cls + "'";

         return html.replace("'${fqn}'", fqn);

     }

     void assertErrors() {

         assertFalse(getErrors().isEmpty(), "There are supposed to be some errors");

     }

     void assertError(String expMsg) {

         StringBuilder sb = new StringBuilder();

         sb.append("Can't find ").append(expMsg).append(" among:");

         for (Diagnostic<? extends JavaFileObject> e : errors) {

             String msg = e.getMessage(Locale.US);

             if (msg.contains(expMsg)) {

                 return;

             }

             sb.append("\n");

             sb.append(msg);

         }

         fail(sb.toString());

     }

 }