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 * 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,
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 *
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package com.sun.tools.internal.xjc.reader.xmlschema;
import static com.sun.tools.internal.xjc.reader.xmlschema.BGMBuilder.getName;

import java.util.Set;

import javax.xml.namespace.QName;

import com.sun.codemodel.internal.JJavaName;
import com.sun.codemodel.internal.JPackage;
import com.sun.istack.internal.NotNull;
import com.sun.istack.internal.Nullable;
import com.sun.tools.internal.xjc.ErrorReceiver;
import com.sun.tools.internal.xjc.model.CClassInfo;
import com.sun.tools.internal.xjc.model.CClassInfoParent;
import com.sun.tools.internal.xjc.model.CClassRef;
import com.sun.tools.internal.xjc.model.CCustomizations;
import com.sun.tools.internal.xjc.model.CElement;
import com.sun.tools.internal.xjc.model.CElementInfo;
import com.sun.tools.internal.xjc.model.Model;
import com.sun.tools.internal.xjc.reader.Ring;
import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BIClass;
import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BIGlobalBinding;
import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BISchemaBinding;
import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BindInfo;
import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BIXSubstitutable;
import com.sun.tools.internal.xjc.reader.xmlschema.ct.ComplexTypeFieldBuilder;
import com.sun.tools.internal.xjc.reader.xmlschema.ct.ComplexTypeBindingMode;
import com.sun.xml.internal.xsom.XSAnnotation;
import com.sun.xml.internal.xsom.XSAttGroupDecl;
import com.sun.xml.internal.xsom.XSAttributeDecl;
import com.sun.xml.internal.xsom.XSAttributeUse;
import com.sun.xml.internal.xsom.XSComplexType;
import com.sun.xml.internal.xsom.XSComponent;
import com.sun.xml.internal.xsom.XSContentType;
import com.sun.xml.internal.xsom.XSDeclaration;
import com.sun.xml.internal.xsom.XSElementDecl;
import com.sun.xml.internal.xsom.XSFacet;
import com.sun.xml.internal.xsom.XSIdentityConstraint;
import com.sun.xml.internal.xsom.XSModelGroup;
import com.sun.xml.internal.xsom.XSModelGroupDecl;
import com.sun.xml.internal.xsom.XSNotation;
import com.sun.xml.internal.xsom.XSParticle;
import com.sun.xml.internal.xsom.XSSchema;
import com.sun.xml.internal.xsom.XSSchemaSet;
import com.sun.xml.internal.xsom.XSSimpleType;
import com.sun.xml.internal.xsom.XSType;
import com.sun.xml.internal.xsom.XSWildcard;
import com.sun.xml.internal.xsom.XSXPath;

import org.xml.sax.Locator;

Default classBinder implementation. Honors <jaxb:class> customizations and default bindings. /**
 * Default classBinder implementation. Honors {@code <jaxb:class>} customizations
 * and default bindings.
 */
final class DefaultClassBinder implements ClassBinder
{
    private final SimpleTypeBuilder stb = Ring.get(SimpleTypeBuilder.class);
    private final Model model = Ring.get(Model.class);

    protected final BGMBuilder builder = Ring.get(BGMBuilder.class);
    protected final ClassSelector selector = Ring.get(ClassSelector.class);

    protected final XSSchemaSet schemas = Ring.get(XSSchemaSet.class);

    public CElement attGroupDecl(XSAttGroupDecl decl) {
        return allow(decl,decl.getName());
    }

    public CElement attributeDecl(XSAttributeDecl decl) {
        return allow(decl,decl.getName());
    }

    public CElement modelGroup(XSModelGroup mgroup) {
        return never();
    }

    public CElement modelGroupDecl(XSModelGroupDecl decl) {
        return never();
    }


    public CElement complexType(XSComplexType type) {
        CElement ci = allow(type,type.getName());
        if(ci!=null)    return ci;

        // no customization is given -- do as the default binding.

        BindInfo bi = builder.getBindInfo(type);

        if(type.isGlobal()) {
            QName tagName = null;
            String className = deriveName(type);
            Locator loc = type.getLocator();

            if(getGlobalBinding().isSimpleMode()) {
                // in the simple mode, we may optimize it away
                XSElementDecl referer = getSoleElementReferer(type);
                if(referer!=null && isCollapsable(referer)) {
                    // if a global element contains
                    // a collpsable complex type, we bind this element to a named one
                    // and collapses element and complex type.
                    tagName = getName(referer);
                    className = deriveName(referer);
                    loc = referer.getLocator();
                }
            }

            // by default, global ones get their own classes.

            JPackage pkg = selector.getPackage(type.getTargetNamespace());

            return new CClassInfo(model,pkg,className, loc,getTypeName(type),tagName,type,bi.toCustomizationList());
        } else {
            XSElementDecl element = type.getScope();

            if( element.isGlobal() && isCollapsable(element)) {
                if(builder.getBindInfo(element).get(BIClass.class)!=null)
                    // the parent element was bound to a class. Don't bind this again to
                    // cause unnecessary wrapping
                    return null;

                // generate one class from element and complex type together.
                // this needs to be done before selector.isBound to avoid infinite recursion.

                // but avoid doing so when the element is mapped to a class,
                // which creates unnecessary classes
                return new CClassInfo( model, selector.getClassScope(),
                    deriveName(element), element.getLocator(), null,
                    getName(element), element, bi.toCustomizationList() );
            }


            CElement parentType = selector.isBound(element,type);

            String className;
            CClassInfoParent scope;


            if( parentType!=null
             && parentType instanceof CElementInfo
             && ((CElementInfo)parentType).hasClass() ) {
                // special case where we put a nested 'Type' element
                scope = (CElementInfo)parentType;
                className = "Type";
            } else {
                // since the parent element isn't bound to a type, merge the customizations associated to it, too.
//                custs = CCustomizations.merge( custs, builder.getBindInfo(type.getScope()).toCustomizationList());
                className = builder.getNameConverter().toClassName(element.getName());

                BISchemaBinding sb = builder.getBindInfo(
                    type.getOwnerSchema() ).get(BISchemaBinding.class);
                if(sb!=null)    className = sb.mangleAnonymousTypeClassName(className);
                scope = selector.getClassScope();
            }

            return new CClassInfo(model, scope, className, type.getLocator(), null, null, type, bi.toCustomizationList() );
        }
    }

    private QName getTypeName(XSComplexType type) {
        if(type.getRedefinedBy()!=null)
            return null;
        else
            return getName(type);
    }

    
Returns true if the complex type of the given element can be "optimized away"
and unified with its parent element decl to form a single class.
/**
     * Returns true if the complex type of the given element can be "optimized away"
     * and unified with its parent element decl to form a single class.
     */
    private boolean isCollapsable(XSElementDecl decl) {
        XSType type = decl.getType();

        if(!type.isComplexType())
            return false;   // not a complex type

        if(decl.getSubstitutables().size()>1 || decl.getSubstAffiliation()!=null)
            // because element substitution calls for a proper JAXBElement hierarchy
            return false;

        if(decl.isNillable())
            // because nillable needs JAXBElement to represent correctly
            return false;

        BIXSubstitutable bixSubstitutable = builder.getBindInfo(decl).get(BIXSubstitutable.class);
        if(bixSubstitutable !=null) {
            // see https://jaxb.dev.java.net/issues/show_bug.cgi?id=289
            // this customization forces non-collapsing behavior.
            bixSubstitutable.markAsAcknowledged();
            return false;
        }

        if( getGlobalBinding().isSimpleMode() && decl.isGlobal()) {
            // in the simple mode, we do more aggressive optimization, and get rid of
            // a complex type class if it's only used once from a global element
            XSElementDecl referer = getSoleElementReferer(decl.getType());
            if(referer!=null) {
                assert referer==decl;  // I must be the sole referer
                return true;
            }
        }

        if(!type.isLocal() || !type.isComplexType())
            return false;

        return true;
    }

    
If only one global XSElementDecl is refering to XSType, return that element, otherwise null. /**
     * If only one global {@link XSElementDecl} is refering to {@link XSType},
     * return that element, otherwise null.
     */
    private @Nullable XSElementDecl getSoleElementReferer(@NotNull XSType t) {
        Set<XSComponent> referer = builder.getReferer(t);

        XSElementDecl sole = null;
        for (XSComponent r : referer) {
            if(r instanceof XSElementDecl) {
                XSElementDecl x = (XSElementDecl) r;
                if(!x.isGlobal())
                    // local element references can be ignored, as their names are either given
                    // by the property, or by the JAXBElement (for things like mixed contents)
                    continue;
                if(sole==null)  sole=x;
                else            return null;    // more than one
            } else {
                // if another type refers to this type, that means
                // this type has a sub-type, so type substitution is possible now.
                return null;
            }
        }

        return sole;
    }

    public CElement elementDecl(XSElementDecl decl) {
        CElement r = allow(decl,decl.getName());

        if(r==null) {
            QName tagName = getName(decl);
            CCustomizations custs = builder.getBindInfo(decl).toCustomizationList();

            if(decl.isGlobal()) {
                if(isCollapsable(decl)) {
                    // we want the returned type to be built as a complex type,
                    // so the binding cannot be delayed.
                    return selector.bindToType(decl.getType().asComplexType(),decl,true);
                } else {
                    String className = null;
                    if(getGlobalBinding().isGenerateElementClass())
                        className = deriveName(decl);

                    // otherwise map global elements to JAXBElement
                    CElementInfo cei = new CElementInfo(
                        model, tagName, selector.getClassScope(), className, custs, decl.getLocator());
                    selector.boundElements.put(decl,cei);

                    stb.refererStack.push(decl);    // referer is element
                    cei.initContentType( selector.bindToType(decl.getType(),decl), decl, decl.getDefaultValue() );
                    stb.refererStack.pop();
                    r = cei;
                }
            }
        }

        // have the substitution member derive from the substitution head
        XSElementDecl top = decl.getSubstAffiliation();
        if(top!=null) {
            CElement topci = selector.bindToType(top,decl);

            if(r instanceof CClassInfo && topci instanceof CClassInfo)
                ((CClassInfo)r).setBaseClass((CClassInfo)topci);
            if (r instanceof CElementInfo && topci instanceof CElementInfo)
                ((CElementInfo)r).setSubstitutionHead((CElementInfo)topci);
        }

        return r;
    }

    public CClassInfo empty( XSContentType ct ) { return null; }

    public CClassInfo identityConstraint(XSIdentityConstraint xsIdentityConstraint) {
        return never();
    }

    public CClassInfo xpath(XSXPath xsxPath) {
        return never();
    }

    public CClassInfo attributeUse(XSAttributeUse use) {
        return never();
    }

    public CElement simpleType(XSSimpleType type) {
        CElement c = allow(type,type.getName());
        if(c!=null) return c;

        if(getGlobalBinding().isSimpleTypeSubstitution() && type.isGlobal()) {
            return new CClassInfo(model,selector.getClassScope(),
                    deriveName(type), type.getLocator(), getName(type), null, type, null );
        }

        return never();
    }

    public CClassInfo particle(XSParticle particle) {
        return never();
    }

    public CClassInfo wildcard(XSWildcard wc) {
        return never();
    }


    // these methods won't be used
    public CClassInfo annotation(XSAnnotation annon) {
        assert false;
        return null;
    }

    public CClassInfo notation(XSNotation not) {
        assert false;
        return null;
    }

    public CClassInfo facet(XSFacet decl) {
        assert false;
        return null;
    }
    public CClassInfo schema(XSSchema schema) {
        assert false;
        return null;
    }





    
Makes sure that the component doesn't carry a BIClass customization. 
Returns:

     return value is unused. Since most of the caller needs to
     return null, to make the code a little bit shorter, this
     method always return null (so that the caller can always
     say return never(sc);./**
     * Makes sure that the component doesn't carry a {@link BIClass}
     * customization.
     *
     * @return
     *      return value is unused. Since most of the caller needs to
     *      return null, to make the code a little bit shorter, this
     *      method always return null (so that the caller can always
     *      say <code>return never(sc);</code>.
     */
    private CClassInfo never() {
        // all we need to do here is just not to acknowledge
        // any class customization. Then this class customization
        // will be reported as an error later when we check all
        // unacknowledged customizations.


//        BIDeclaration cust=owner.getBindInfo(component).get(BIClass.NAME);
//        if(cust!=null) {
//            // error
//            owner.errorReporter.error(
//                cust.getLocation(),
//                "test {0}", NameGetter.get(component) );
//        }
        return null;
    }

    
Checks if a component carries a customization to map it to a class.
If so, make it a class.
Params:
defaultBaseName – 
     The token which will be used as the basis of the class name
     if the class name is not specified in the customization.
     This is usually the name of an element declaration, and so on.
     This parameter can be null, in that case it would be an error
     if a name is not given by the customization./**
     * Checks if a component carries a customization to map it to a class.
     * If so, make it a class.
     *
     * @param defaultBaseName
     *      The token which will be used as the basis of the class name
     *      if the class name is not specified in the customization.
     *      This is usually the name of an element declaration, and so on.
     *
     *      This parameter can be null, in that case it would be an error
     *      if a name is not given by the customization.
     */
    private CElement allow( XSComponent component, String defaultBaseName ) {

        BIClass decl = null;

        if(component instanceof XSComplexType) {
            XSType complexType = (XSType)component;

            BIClass lastFoundRecursiveBiClass = null;

            if(complexType.getName() != null) {
                while( ! schemas.getAnyType().equals(complexType)) {
                    BindInfo bindInfo = builder.getBindInfo(complexType);
                    BIClass biClass = bindInfo.get(BIClass.class);

                    if(biClass != null && "true".equals(biClass.getRecursive()))
                        lastFoundRecursiveBiClass = biClass;

                    complexType = complexType.getBaseType();
                }
            }

            // use this as biclass for current component
            decl = lastFoundRecursiveBiClass;

        }

        BindInfo bindInfo = builder.getBindInfo(component);
        if(decl == null) {
            decl = bindInfo.get(BIClass.class);
            if(decl==null)  return null;
        }

        decl.markAsAcknowledged();

        // first consider binding to the class reference.
        String ref = decl.getExistingClassRef();
        if(ref!=null) {
            if(!JJavaName.isFullyQualifiedClassName(ref)) {
                Ring.get(ErrorReceiver.class).error( decl.getLocation(),
                    Messages.format(Messages.ERR_INCORRECT_CLASS_NAME,ref) );
                // recover by ignoring @ref
            } else {
                if(component instanceof XSComplexType) {
                    // UGLY UGLY UGLY
                    // since we are not going to bind this complex type, we need to figure out
                    // its binding mode without actually binding it (and also expose this otherwise
                    // hidden mechanism into this part of the code.)
                    //
                    // this code is potentially dangerous as the base class might have been bound
                    // in different ways. To be correct, we need to figure out how the content type
                    // would have been bound, from the schema.
                    Ring.get(ComplexTypeFieldBuilder.class).recordBindingMode(
                        (XSComplexType)component, ComplexTypeBindingMode.NORMAL
                    );
                }
                return new CClassRef(model, component, decl, bindInfo.toCustomizationList() );
            }
        }

        String clsName = decl.getClassName();
        if(clsName==null) {
            // if the customiztion doesn't give us a name, derive one
            // from the current component.
            if( defaultBaseName==null ) {
                Ring.get(ErrorReceiver.class).error( decl.getLocation(),
                    Messages.format(Messages.ERR_CLASS_NAME_IS_REQUIRED) );

                // recover by generating a pseudo-random name
                defaultBaseName = "undefined"+component.hashCode();
            }
            clsName = builder.deriveName( defaultBaseName, component );
        } else {
            if( !JJavaName.isJavaIdentifier(clsName) ) {
                // not a valid Java class name
                Ring.get(ErrorReceiver.class).error( decl.getLocation(),
                    Messages.format( Messages.ERR_INCORRECT_CLASS_NAME, clsName ));
                // recover by a dummy name
                clsName = "Undefined"+component.hashCode();
            }
        }

        QName typeName = null;
        QName elementName = null;

        if(component instanceof XSType) {
            XSType t = (XSType) component;
            typeName = getName(t);
        }

        if (component instanceof XSElementDecl) {
            XSElementDecl e = (XSElementDecl) component;
            elementName = getName(e);
        }

        if (component instanceof XSElementDecl && !isCollapsable((XSElementDecl)component)) {
            XSElementDecl e = ((XSElementDecl)component);

            CElementInfo cei = new CElementInfo(model, elementName,
                    selector.getClassScope(), clsName,
                    bindInfo.toCustomizationList(), decl.getLocation() );
            selector.boundElements.put(e,cei);

            stb.refererStack.push(component);    // referer is element
            cei.initContentType(
                selector.bindToType(e.getType(),e),
                e,e.getDefaultValue());
            stb.refererStack.pop();
            return cei;
            // TODO: support javadoc and userSpecifiedImplClass
        } else {
            CClassInfo bt = new CClassInfo(model,selector.getClassScope(),
                    clsName, decl.getLocation(), typeName, elementName, component, bindInfo.toCustomizationList() );

            // set javadoc class comment.
            if(decl.getJavadoc()!=null )
                bt.javadoc = decl.getJavadoc()+"\n\n";
                // add extra blank lines so that the schema fragment
                // and user-specified javadoc would be separated


            // if the implClass is given, set it to ClassItem
            String implClass = decl.getUserSpecifiedImplClass();
            if( implClass!=null )
                bt.setUserSpecifiedImplClass( implClass );

            return bt;
        }
    }

    private BIGlobalBinding getGlobalBinding() {
        return builder.getGlobalBinding();
    }

    
Derives a name from a schema component.
Use the name of the schema component as the default name.
/**
     * Derives a name from a schema component.
     * Use the name of the schema component as the default name.
     */
    private String deriveName( XSDeclaration comp ) {
        return builder.deriveName( comp.getName(), comp );
    }

    
Derives a name from a schema component.
For complex types, we take redefinition into account when
deriving a default name.
/**
     * Derives a name from a schema component.
     * For complex types, we take redefinition into account when
     * deriving a default name.
     */
    private String deriveName( XSComplexType comp ) {
        String seed = builder.deriveName( comp.getName(), comp );
        int cnt = comp.getRedefinedCount();
        for( ; cnt>0; cnt-- )
            seed = "Original"+seed;
        return seed;
    }

}