/**

  * 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.ide.editor;

 import com.sun.source.tree.AnnotationTree;

 import com.sun.source.tree.ExpressionTree;

 import com.sun.source.tree.LiteralTree;

 import com.sun.source.tree.MethodTree;

 import com.sun.source.tree.Tree.Kind;

 import com.sun.source.tree.VariableTree;

 import com.sun.source.util.TreePath;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.Collections;

 import java.util.List;

 import java.util.regex.Matcher;

 import java.util.regex.Pattern;

 import org.netbeans.api.java.lexer.JavaTokenId;

 import static org.netbeans.api.java.lexer.JavaTokenId.BLOCK_COMMENT;

 import static org.netbeans.api.java.lexer.JavaTokenId.JAVADOC_COMMENT;

 import static org.netbeans.api.java.lexer.JavaTokenId.LINE_COMMENT;

 import static org.netbeans.api.java.lexer.JavaTokenId.WHITESPACE;

 import org.netbeans.api.java.source.CompilationInfo;

 import org.netbeans.api.java.source.TreeMaker;

 import org.netbeans.api.lexer.Token;

 import org.netbeans.api.lexer.TokenSequence;

 import org.netbeans.spi.editor.hints.ErrorDescription;

 import org.netbeans.spi.editor.hints.Fix;

 import org.netbeans.spi.java.hints.ErrorDescriptionFactory;

 import org.netbeans.spi.java.hints.Hint;

 import org.netbeans.spi.java.hints.HintContext;

 import org.netbeans.spi.java.hints.JavaFix;

 import org.netbeans.spi.java.hints.TriggerTreeKind;

 import org.openide.util.NbBundle.Messages;

 @Hint(displayName = "#DN_JSNI2JavaScriptBody", description = "#DESC_JSNI2JavaScriptBody", category = "general")

 @Messages({

     "DN_JSNI2JavaScriptBody=JSNI to @JavaScriptBody",

     "DESC_JSNI2JavaScriptBody=JSNI to @JavaScriptBody"

 })

 public class JSNI2JavaScriptBody {

     private static final Pattern JSNIPattern = Pattern.compile("/\\*-\\{(.*)}-\\*/");

     @TriggerTreeKind(Kind.METHOD)

     @Messages("ERR_JSNI2JavaScriptBody=Can convert JSNI to @JavaScriptBody")

     public static ErrorDescription computeWarning(final HintContext ctx) {

         Token<JavaTokenId> token = findBlockToken(ctx.getInfo(), ctx.getPath(), ctx);

         if (token == null) {

             return null;

         }

         Fix fix = new FixImpl(ctx.getInfo(), ctx.getPath()).toEditorFix();

         return ErrorDescriptionFactory.forName(ctx, ctx.getPath(), Bundle.ERR_JSNI2JavaScriptBody(), fix);

     }

     private static Token<JavaTokenId> findBlockToken(CompilationInfo info, TreePath path, HintContext ctx) {

         int end = (int) info.getTrees().getSourcePositions().getEndPosition(path.getCompilationUnit(), path.getLeaf());

         TokenSequence<JavaTokenId> ts = info.getTokenHierarchy().tokenSequence(JavaTokenId.language());

         if (ts == null) return null;

         ts.move(end);

         if ((ctx != null && ctx.isCanceled()) || !ts.movePrevious() || ts.token().id() != JavaTokenId.SEMICOLON) return null;

         OUTER: while (ts.movePrevious()) {

             if (ctx != null && ctx.isCanceled()) return null;

             switch (ts.token().id()) {

                 case WHITESPACE: break;

                 case LINE_COMMENT: break;

                 case JAVADOC_COMMENT: break;

                 case BLOCK_COMMENT:

                     if (JSNIPattern.matcher(ts.token().text()).matches()) {

                         return ts.offsetToken();

                     }

                     break;

                 default:

                     break OUTER;

             }

         }

         return null;

     }

     private static final class FixImpl extends JavaFix {

         public FixImpl(CompilationInfo info, TreePath tp) {

             super(info, tp);

         }

         @Override

         @Messages("FIX_JSNI2JavaScriptBody=Convert JSNI to @JavaScriptBody")

         protected String getText() {

             return Bundle.FIX_JSNI2JavaScriptBody();

         }

         @Override

         protected void performRewrite(TransformationContext ctx) {

             Token<JavaTokenId> jsniComment = findBlockToken(ctx.getWorkingCopy(), ctx.getPath(), null);

             if (jsniComment == null) {

                 //XXX: warn?

                 return ;

             }

             Matcher m = JSNIPattern.matcher(jsniComment.text());

             if (!m.matches()) return ; //XXX: warn?

             TreeMaker make = ctx.getWorkingCopy().getTreeMaker();

             MethodTree mt = (MethodTree) ctx.getPath().getLeaf();

             List<LiteralTree> params = new ArrayList<LiteralTree>();

             params.add(make.Literal("this"));

             for (VariableTree p : mt.getParameters()) {

                 params.add(make.Literal(p.getName().toString()));

             }

             AnnotationTree jsBody = make.Annotation(make.QualIdent("org.apidesign.bck2brwsr.core.JavaScriptBody"),

                 Arrays.<ExpressionTree>asList(

                     make.Assignment(make.Identifier("body"), make.Literal(m.group(1))),

                     make.Assignment(make.Identifier("args"), make.NewArray(null, Collections.<ExpressionTree>emptyList(), params))

                 )

             );

             ctx.getWorkingCopy().rewrite(mt.getModifiers(), make.addModifiersAnnotation(mt.getModifiers(), jsBody));

         }

     }

 }