/**

  * Back 2 Browser Bytecode Translator

  * Copyright (C) 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.OutputStreamWriter;

 import java.io.Writer;

 import java.util.Arrays;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.Map;

 import java.util.Map.Entry;

 import java.util.ServiceLoader;

 import javax.annotation.processing.ProcessingEnvironment;

 import javax.lang.model.element.Element;

 import javax.tools.Diagnostic;

 import javax.tools.FileObject;

 import org.netbeans.modules.html.editor.lib.api.HtmlVersion;

 import org.netbeans.modules.html.editor.lib.api.model.HtmlModel;

 import org.netbeans.modules.html.editor.lib.api.model.HtmlModelProvider;

 import org.netbeans.modules.html.editor.lib.api.model.HtmlTag;

 import org.netbeans.modules.html.editor.lib.api.model.HtmlTagAttribute;

 /**

  *

  * @author Jan Horvath <jhorvath@netbeans.org>

  */

 final class ElementGenerator {

     static final Map<String, String> NAMING_EXCEPTIONS = new HashMap<String, String>() {

         {

             put("img", "Image");

             put("class", "Clazz");

         }

     };

     static final String javaKeywords[] = {

         "abstract", "assert", "boolean", "break", "byte", "case",

         "catch", "char", "class", "const", "continue", "default", 

         "do", "double", "else", "extends", "false", "final", "finally", 

         "float", "for", "goto", "if", "implements", "import", 

         "instanceof", "int", "interface", "long", "native", "new",

         "null", "package", "private", "protected", "public",

         "return", "short", "static", "strictfp", "super",

         "switch", "synchronized", "this", "throw", "throws",

         "transient", "true", "try", "void", "volatile", "while"

     };

     private static Map<String, String> elements = new HashMap<String, String>();

     private final ProcessingEnvironment processingEnv;

     private HtmlModel model = null;

     ElementGenerator(ProcessingEnvironment processingEnv) {

         this.processingEnv = processingEnv;

     }

     String getType(String pkg, String tag, Element e) {

         String className = elements.get(tag);

         if (className == null) {

             className = createClass(pkg, tag, e);

             elements.put(tag, className);

         }

         return className;

     }

     private String createClass(String pkg, String tag, Element e) {

         String className = className(tag);

         Writer w;

         try {

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

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

             try {

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

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

                 PredefinedFields.appendImports(w, tag);

                 w.append("\n");

                 w.append("class ").append(className).append(" extends Element {\n\n");

                 w.append("    public ").append(className).append("(String id) {\n");

                 w.append("        super(id);\n");

                 w.append("    }\n\n");

                 for (Entry<String, String> entry : getAttributes(tag).entrySet()) {

                     String attrName = entry.getKey();

                     String attrType = entry.getValue();

                     // getter

                     w.append("    public ").append(attrType).append(" ")

                             .append("get").append(className(attrName)).append("() {\n");

                     w.append("        return (").append(attrType).append(")getAttribute(\"")

                             .append(attrName).append("\");\n");

                     w.append("    }\n\n");

                     // setter

                     w.append("    public void ")

                             .append("set").append(className(attrName)).append("(")

                             .append(attrType).append(" ").append(attributeName(attrName)).append(") {\n");

                     w.append("        setAttribute(\"").append(attrName).append("\", ").append(attributeName(attrName)).append(");\n");

                     w.append("    }\n\n");

                 }

                 PredefinedFields.appendFields(w, tag);

                 w.append("}\n");

             } finally {

                 w.close();

             }

         } catch (IOException ex) {

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

             return null;

         }

         return className;

     }

     Map<String, String> getAttributes(String tagName) {

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

         if (model == null) {

             // HtmlModelProvider modelProvider = Lookup.getDefault().lookup(HtmlModelProvider.class);

             ServiceLoader<HtmlModelProvider> hmpLoader = 

                     ServiceLoader.load(HtmlModelProvider.class, this.getClass().getClassLoader());

             for (HtmlModelProvider htmlModelProvider : hmpLoader) {

                 model = htmlModelProvider.getModel(HtmlVersion.HTML5);

                 if (model != null) {

                     break;

                 }

             }

         }

         if (model == null) {

             processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, 

                     "HTML 5 model provider was not found on classpath");

             return Collections.emptyMap();

         }

         HtmlTag tag = model.getTag(tagName);

         for (HtmlTagAttribute attr : tag.getAttributes()) {

             String name = attr.getName();

             String type = Attributes.TYPES.get(name);

             if (type != null) {

                 result.put(name, type);

             }

         }

         return result;

     }

     private String className(String s) {

         if (s.length() == 0) {

             return s;

         }

         String name = NAMING_EXCEPTIONS.get(s.toLowerCase());

         if (name == null) {

             name = s.substring(0, 1).toUpperCase() + s.substring(1).toLowerCase();

         }

         return name;

     }

     private String attributeName(String s) {

         if (Arrays.binarySearch(javaKeywords, s) >= 0) {

             return String.format("%sAttr", s);

         }

         return s;

     }

 }