/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.netbeans.modules.web.beans.hints;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicReference;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.lang.model.element.Element;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.TypeElement;
import javax.lang.model.element.VariableElement;
import javax.swing.text.Document;
import javax.swing.text.StyledDocument;

import org.netbeans.modules.editor.NbEditorUtilities;
import org.netbeans.modules.web.beans.analysis.CdiAnalysisResult;
import org.netbeans.modules.web.beans.analysis.CdiEditorAnalysisFactory;
import org.netbeans.modules.web.beans.analysis.analyzer.ModelAnalyzer.Result;
import org.netbeans.modules.web.beans.hints.CDIAnnotation.CDIAnnotaitonType;
import org.openide.cookies.EditorCookie;
import org.openide.filesystems.FileObject;
import org.openide.loaders.DataObject;
import org.openide.text.Line;
import org.openide.text.Line.Part;
import org.openide.text.NbDocument;
import org.openide.util.RequestProcessor;

import com.sun.source.tree.Tree;


/**
 * @author ads
 *
 */
public final class EditorAnnotationsHelper implements PropertyChangeListener {
    
    private static ConcurrentHashMap<DataObject, EditorAnnotationsHelper> HELPERS 
        = new ConcurrentHashMap<DataObject, EditorAnnotationsHelper>();
    
    private static final RequestProcessor PROCESSOR = new RequestProcessor(
            EditorAnnotationsHelper.class.getName(), 1, false, false);
    
    private EditorAnnotationsHelper( DataObject dataObject , 
            EditorCookie.Observable observable )
    {
        myDataObject = dataObject;
        myObservable = observable;
        myModelAnnotations = new AtomicReference<List<CDIAnnotation>>(
                Collections.<CDIAnnotation>emptyList());
        myAnnotations = new AtomicReference<List<CDIAnnotation>>(
                Collections.<CDIAnnotation>emptyList());
        
        observable.addPropertyChangeListener(this );
    }
    
    /* (non-Javadoc)
     * @see java.beans.PropertyChangeListener#propertyChange(java.beans.PropertyChangeEvent)
     */
    @Override
    public void propertyChange( PropertyChangeEvent evt ) {
        if (EditorCookie.Observable.PROP_OPENED_PANES.endsWith(evt.getPropertyName()) 
                || evt.getPropertyName() == null)
        {
            if (myObservable.getOpenedPanes() == null) {
                myObservable.removePropertyChangeListener(this);

                Runnable runnable = new Runnable() {

                    @Override
                    public void run() {
                        HELPERS.remove(myDataObject);
                        List<CDIAnnotation> annotations = myModelAnnotations.get();
                        for (CDIAnnotation annotation : annotations) {
                            annotation.detach();
                        }
                        annotations = myAnnotations.get();
                        for( CDIAnnotation annotation : annotations ){
                            annotation.detach();
                        }
                        myModelAnnotations.set( Collections.<CDIAnnotation>emptyList());
                        myAnnotations.set( Collections.<CDIAnnotation>emptyList());
                    }
                };
                PROCESSOR.submit(runnable);
            }
        }        
    }
    
    public static EditorAnnotationsHelper getInstance( CdiAnalysisResult result ){
        return getInstance( result.getInfo().getFileObject());
    }
    
    public static EditorAnnotationsHelper getInstance( FileObject fileObject ){
        try {
            DataObject dataObject = DataObject.find(fileObject);
            EditorAnnotationsHelper helper = HELPERS.get(dataObject);

            if (helper != null) {
                return helper;
            }

            EditorCookie.Observable observable = dataObject.getLookup().lookup(
                    EditorCookie.Observable.class);

            if (observable == null) {
                return null;
            }

            helper = new EditorAnnotationsHelper( dataObject , observable );
            HELPERS.put(dataObject, helper );

            return helper;
        } catch (IOException ex) {
            Logger.getLogger( EditorAnnotationsHelper.class.getName() ).
                log(Level.INFO, null, ex);
            return null;
        }
    }

    public void addInjectionPoint( CdiAnalysisResult result, VariableElement element )
    {
        addAnnotation(result, element, CDIAnnotaitonType.INJECTION_POINT );
    }

    public void addDelegate( CdiAnalysisResult result ,  VariableElement element ) {
        addAnnotation(result, element, CDIAnnotaitonType.DELEGATE_POINT );
    }
    
    public void addEventInjectionPoint( Result result, VariableElement element )
    {
        addAnnotation(result, element, CDIAnnotaitonType.EVENT );        
    }
    
    public void addObserver( CdiAnalysisResult result, ExecutableElement element )
    {
        addAnnotation(result, element, CDIAnnotaitonType.OBSERVER );           
    }
    
    public void addInterceptedBean(CdiAnalysisResult result , TypeElement element ) {
        addAnnotation(result, element, CDIAnnotaitonType.INTERCEPTED_ELEMENT );        
    }
    
    public void addInterceptedMethod( Result result, ExecutableElement element )
    {
        addAnnotation(result, element, CDIAnnotaitonType.INTERCEPTED_ELEMENT );
    }
    
    public void addDecoratedBean( Result result, TypeElement element ) {
        addAnnotation(result, element, CDIAnnotaitonType.DECORATED_BEAN );
    }

    public void publish( final CdiAnalysisResult result ) {
        Runnable runnable = new Runnable() {
            
            @Override
            public void run() {
                AtomicReference<List<CDIAnnotation>> ref ;
                if ( result instanceof Result ){
                    ref = myAnnotations;
                }
                else if ( result.getClass() == CdiAnalysisResult.class ){
                    ref = myModelAnnotations;
                }
                else {
                    ref = null;
                    assert false;
                }
                List<CDIAnnotation> annotations = ref.get();
                for (CDIAnnotation annotation : annotations) {
                    annotation.detach();
                }
                List<CDIAnnotation> collected = result.getAnnotations();
                
                for (CDIAnnotation annotation : collected) {
                    annotation.attach( annotation.getPart() );
                }
                ref.set(collected);
            }
        };
        PROCESSOR.submit(runnable);
    }
    
    public List<CDIAnnotation> getAnnotations(){
        List<CDIAnnotation> modelAnnotations = myModelAnnotations.get();
        List<CDIAnnotation> annotations = myAnnotations.get();
        List<CDIAnnotation> result = new ArrayList<CDIAnnotation>( 
                modelAnnotations.size() +annotations.size());
        result.addAll( modelAnnotations);
        result.addAll( annotations );
        return result;
    }

    private void addAnnotation( CdiAnalysisResult result, Element element , 
            CDIAnnotaitonType type ) 
    {
        if ( element == null ){
            return;
        }
        Tree var = result.getInfo().getTrees().getTree( element );
        if ( var == null ){
            return;
        }
        List<Integer> position = CdiEditorAnalysisFactory.getElementPosition( 
                result.getInfo(),  var );
        Document document;
        try {
            document = result.getInfo().getDocument();
            if ( !( document instanceof StyledDocument) ){
                return;
            }
        }
        catch (IOException e) {
            return;
        }
        int start = position.get(0);
        Line line = NbEditorUtilities.getLine( document , start, false);
        Part part = line.createPart( NbDocument.findLineColumn((StyledDocument) document,
                start),  position.get( 1 ) -start);
        result.addAnnotation( new CDIAnnotation( type, part));
    }
    
    private DataObject myDataObject;
    private EditorCookie.Observable myObservable;
    private AtomicReference<List<CDIAnnotation>> myModelAnnotations;
    private AtomicReference<List<CDIAnnotation>> myAnnotations;

}
