/**

  * Java 4 Browser Bytecode Translator

  * Copyright (C) 2012-2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>

  *

  * This program is free software: you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation, version 2 of the License.

  *

  * This program is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  * GNU General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License

  * along with this program. Look for COPYING file in the top folder.

  * If not, see http://opensource.org/licenses/GPL-2.0.

  */

 package org.apidesign.bck2brwsr.htmlpage;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStreamWriter;

 import java.io.Writer;

 import java.util.Locale;

 import java.util.Set;

 import javax.annotation.processing.AbstractProcessor;

 import javax.annotation.processing.Processor;

 import javax.annotation.processing.RoundEnvironment;

 import javax.annotation.processing.SupportedAnnotationTypes;

 import javax.lang.model.element.Element;

 import javax.lang.model.element.PackageElement;

 import javax.lang.model.element.TypeElement;

 import javax.tools.Diagnostic;

 import javax.tools.FileObject;

 import javax.tools.StandardLocation;

 import org.apidesign.bck2brwsr.htmlpage.api.Page;

 import org.openide.util.lookup.ServiceProvider;

 /** Annotation processor to process an XHTML page and generate appropriate 

  * "id" file.

  *

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

  */

 @ServiceProvider(service=Processor.class)

 @SupportedAnnotationTypes("org.apidesign.bck2brwsr.htmlpage.api.Page")

 public final class PageProcessor extends AbstractProcessor {

     @Override

     public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

         for (Element e : roundEnv.getElementsAnnotatedWith(Page.class)) {

             Page p = e.getAnnotation(Page.class);

             PackageElement pe = (PackageElement)e;

             String pkg = pe.getQualifiedName().toString();

             ProcessPage pp;

             try {

                 InputStream is = openStream(pkg, p.xhtml());

                 pp = ProcessPage.readPage(is);

                 is.close();

             } catch (IOException iOException) {

                 processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, "Can't read " + p.xhtml(), e);

                 return false;

             }

             Writer w;

             try {

                 FileObject java = processingEnv.getFiler().createSourceFile(pkg + '.' + p.name(), e);

                 w = new OutputStreamWriter(java.openOutputStream());

                 w.append("package " + pkg + ";\n");

                 w.append("import org.apidesign.bck2brwsr.htmlpage.api.*;\n");

                 w.append("class ").append(p.name()).append(" {\n");

                 for (String id : pp.ids()) {

                     String tag = pp.tagNameForId(id);

                     String type = type(tag);

                     w.append("  ").append("public static final ").

                         append(type).append(' ').append(cnstnt(id)).append(" = new ").

                         append(type).append("(\"").append(id).append("\");\n");

                 }

                 w.append("}");

                 w.close();

             } catch (IOException ex) {

                 processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, "Can't create " + p.name() + ".java", e);

                 return false;

             }

         }

         return true;

     }

     private InputStream openStream(String pkg, String name) throws IOException {

         FileObject fo = processingEnv.getFiler().getResource(

             StandardLocation.SOURCE_PATH, pkg, name);

         try {

             return fo.openInputStream();

         } catch (IOException ex) {

             return processingEnv.getFiler().getResource(StandardLocation.CLASS_OUTPUT, pkg, name).openInputStream();

         }

     }

     private static String type(String tag) {

         if (tag.equals("title")) {

             return "Title";

         }

         if (tag.equals("button")) {

             return "Button";

         }

         if (tag.equals("input")) {

             return "Input";

         }

         return "Element";

     }

     private static String cnstnt(String id) {

         return id.toUpperCase(Locale.ENGLISH).replace('.', '_');

     }

 }