/*

 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.

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

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

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

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.tools.internal.xjc.reader.internalizer;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Iterator;

import java.util.List;

import javax.xml.bind.JAXBException;

import javax.xml.bind.Unmarshaller;

import javax.xml.bind.UnmarshallerHandler;

import javax.xml.validation.ValidatorHandler;

import com.sun.istack.internal.NotNull;

import com.sun.istack.internal.SAXParseException2;

import com.sun.tools.internal.xjc.ErrorReceiver;

import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BIDeclaration;

import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BindInfo;

import com.sun.tools.internal.xjc.util.ForkContentHandler;

import com.sun.tools.internal.xjc.util.DOMUtils;

import com.sun.xml.internal.xsom.SCD;

import com.sun.xml.internal.xsom.XSAnnotation;

import com.sun.xml.internal.xsom.XSComponent;

import com.sun.xml.internal.xsom.XSSchemaSet;

import org.w3c.dom.Element;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

/**

 * Set of binding nodes that have target nodes specified via SCD.

 *

 * This is parsed during {@link Internalizer} works on the tree,

 * but applying this has to wait for {@link XSSchemaSet} to be parsed.

 *

 * @author Kohsuke Kawaguchi

 * @see SCD

 */

public final class SCDBasedBindingSet {

    /**

     * Represents the target schema component of the

     * customization identified by SCD.

     *

     * @author Kohsuke Kawaguchi

     */

    final class Target {

        /**

         * SCDs can be specified via multiple steps, like:

         *

         * <bindings scd="foo/bar">

         *   <bindings scd="zot/xyz">

         *

         * This field and {@link #nextSibling} form a single-linked list that

         * represent the children that shall be evaluated within this target.

         * Think of it as {@code List<Target>}.

         */

        private Target firstChild;

        private final Target nextSibling;

        /**

         * Compiled SCD.

         */

        private final @NotNull SCD scd;

        /**

         * The element on which SCD was found.

         */

        private final @NotNull Element src;

        /**

         * Bindings that apply to this SCD.

         */

        private final List<Element> bindings = new ArrayList<Element>();

        private Target(Target parent, Element src, SCD scd) {

            if(parent==null) {

                this.nextSibling = topLevel;

                topLevel = this;

            } else {

                this.nextSibling = parent.firstChild;

                parent.firstChild = this;

            }

            this.src = src;

            this.scd = scd;

        }

        /**

         * Adds a new binding declaration to be associated to the schema component

         * identified by {@link #scd}.

         */

        void addBinidng(Element binding) {

            bindings.add(binding);

        }

        /**

         * Applies bindings to the schema component for this and its siblings.

         */

        private void applyAll(Collection<? extends XSComponent> contextNode) {

            for( Target self=this; self!=null; self=self.nextSibling )

                self.apply(contextNode);

        }

        /**

         * Applies bindings to the schema component for just this node.

         */

        private void apply(Collection<? extends XSComponent> contextNode) {

            // apply the SCD...

            Collection<XSComponent> childNodes = scd.select(contextNode);

            if(childNodes.isEmpty()) {

                // no node matched

                if(src.getAttributeNode("if-exists")!=null) {

                    // if this attribute exists, it's not an error if SCD didn't match.

                    return;

                }

                reportError( src, Messages.format(Messages.ERR_SCD_EVALUATED_EMPTY,scd) );

                return;

            }

            if(firstChild!=null)

                    firstChild.applyAll(childNodes);

            if(!bindings.isEmpty()) {

                // error to match more than one components

                Iterator<XSComponent> itr = childNodes.iterator();

                XSComponent target = itr.next();

                if(itr.hasNext()) {

                    reportError( src, Messages.format(Messages.ERR_SCD_MATCHED_MULTIPLE_NODES,scd,childNodes.size()) );

                    errorReceiver.error( target.getLocator(), Messages.format(Messages.ERR_SCD_MATCHED_MULTIPLE_NODES_FIRST) );

                    errorReceiver.error( itr.next().getLocator(), Messages.format(Messages.ERR_SCD_MATCHED_MULTIPLE_NODES_SECOND) );

                }

                // apply bindings to the target

                for (Element binding : bindings) {

                    for (Element item : DOMUtils.getChildElements(binding)) {

                        String localName = item.getLocalName();

                        if ("bindings".equals(localName))

                            continue;   // this should be already in Target.bindings of some SpecVersion.

                        try {

                            new DOMForestScanner(forest).scan(item,loader);

                            BIDeclaration decl = (BIDeclaration)unmarshaller.getResult();

                            // add this binding to the target

                            XSAnnotation ann = target.getAnnotation(true);

                            BindInfo bi = (BindInfo)ann.getAnnotation();

                            if(bi==null) {

                                bi = new BindInfo();

                                ann.setAnnotation(bi);

                            }

                            bi.addDecl(decl);

                        } catch (SAXException e) {

                            // the error should have already been reported.

                        } catch (JAXBException e) {

                            // if validation didn't fail, then unmarshalling can't go wrong

                            throw new AssertionError(e);

                        }

                    }

                }

            }

        }

    }

    private Target topLevel;

    /**

     * The forest where binding elements came from. Needed to report line numbers for errors.

     */

    private final DOMForest forest;

    // variables used only during the apply method

    //

    private ErrorReceiver errorReceiver;

    private UnmarshallerHandler unmarshaller;

    private ForkContentHandler loader; // unmarshaller+validator

    SCDBasedBindingSet(DOMForest forest) {

        this.forest = forest;

    }

    Target createNewTarget(Target parent, Element src, SCD scd) {

        return new Target(parent,src,scd);

    }

    /**

     * Applies the additional binding customizations.

     */

    public void apply(XSSchemaSet schema, ErrorReceiver errorReceiver) {

        if(topLevel!=null) {

            this.errorReceiver = errorReceiver;

            Unmarshaller u =  BindInfo.getCustomizationUnmarshaller();

            this.unmarshaller = u.getUnmarshallerHandler();

            ValidatorHandler v = BindInfo.bindingFileSchema.newValidator();

            v.setErrorHandler(errorReceiver);

            loader = new ForkContentHandler(v,unmarshaller);

            topLevel.applyAll(schema.getSchemas());

            this.loader = null;

            this.unmarshaller = null;

            this.errorReceiver = null;

        }

    }

    private void reportError( Element errorSource, String formattedMsg ) {

        reportError( errorSource, formattedMsg, null );

    }

    private void reportError( Element errorSource,

                              String formattedMsg, Exception nestedException ) {

        SAXParseException e = new SAXParseException2( formattedMsg,

            forest.locatorTable.getStartLocation(errorSource),

            nestedException );

        errorReceiver.error(e);

    }

}