/*
 * 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.apache.xerces.impl.xs.traversers;

import java.util.Stack;
import java.util.Vector;

import org.apache.xerces.impl.validation.ValidationState;
import org.apache.xerces.impl.xs.SchemaNamespaceSupport;
import org.apache.xerces.impl.xs.SchemaSymbols;
import org.apache.xerces.impl.xs.XMLSchemaException;
import org.apache.xerces.impl.xs.util.XInt;
import org.apache.xerces.util.SymbolTable;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

/**
 * Objects of this class hold all information pecular to a
 * particular XML Schema document.  This is needed because
 * namespace bindings and other settings on the <schema/> element
 * affect the contents of that schema document alone.
 *
 * @xerces.internal 
 *
 * @author Neil Graham, IBM
 * @version $Id$
 */
class XSDocumentInfo {

    // Data
    protected SchemaNamespaceSupport fNamespaceSupport;
    protected SchemaNamespaceSupport fNamespaceSupportRoot;
    protected Stack SchemaNamespaceSupportStack = new Stack();

    // schema's attributeFormDefault
    protected boolean fAreLocalAttributesQualified;

    // elementFormDefault
    protected boolean fAreLocalElementsQualified;

    // [block | final]Default
    protected short fBlockDefault;
    protected short fFinalDefault;

    // targetNamespace
    String fTargetNamespace;

    // represents whether this is a chameleon schema (i.e., whether its TNS is natural or comes from without)
    protected boolean fIsChameleonSchema;

    // the root of the schema Document tree itself
    protected Element fSchemaElement;

    // all namespaces that this document can refer to
    Vector fImportedNS = new Vector();
    
    protected ValidationState fValidationContext = new ValidationState();

    SymbolTable fSymbolTable = null;

    // attribute checker to which we'll return the attributes 
    // once we've been told that we're done with them
    protected XSAttributeChecker fAttrChecker;

    // array of objects on the schema's root element.  This is null
    // once returnSchemaAttrs has been called.
    protected Object [] fSchemaAttrs;
    
    // list of annotations contained in the schema document. This is null
    // once removeAnnotations has been called.
    protected XSAnnotationInfo fAnnotations = null;

    // note that the caller must ensure to call returnSchemaAttrs()
    // to avoid memory leaks!
    XSDocumentInfo (Element schemaRoot, XSAttributeChecker attrChecker, SymbolTable symbolTable)
                    throws XMLSchemaException {
        
        fSchemaElement = schemaRoot;
        fNamespaceSupport = new SchemaNamespaceSupport(schemaRoot, symbolTable);
        fNamespaceSupport.reset();
        fIsChameleonSchema = false;

        fSymbolTable = symbolTable;
        fAttrChecker = attrChecker;

        if (schemaRoot != null) {
            Element root = schemaRoot;
            fSchemaAttrs = attrChecker.checkAttributes(root, true, this);
            // schemaAttrs == null means it's not an <xsd:schema> element
            // throw an exception, but we don't know the document systemId,
            // so we leave that to the caller.
            if (fSchemaAttrs == null) {
                throw new XMLSchemaException(null, null);
            }
            fAreLocalAttributesQualified =
                ((XInt)fSchemaAttrs[XSAttributeChecker.ATTIDX_AFORMDEFAULT]).intValue() == SchemaSymbols.FORM_QUALIFIED;
            fAreLocalElementsQualified =
                ((XInt)fSchemaAttrs[XSAttributeChecker.ATTIDX_EFORMDEFAULT]).intValue() == SchemaSymbols.FORM_QUALIFIED;
            fBlockDefault =
                ((XInt)fSchemaAttrs[XSAttributeChecker.ATTIDX_BLOCKDEFAULT]).shortValue();
            fFinalDefault =
                ((XInt)fSchemaAttrs[XSAttributeChecker.ATTIDX_FINALDEFAULT]).shortValue();
            fTargetNamespace =
                (String)fSchemaAttrs[XSAttributeChecker.ATTIDX_TARGETNAMESPACE];
            if (fTargetNamespace != null)
                fTargetNamespace = symbolTable.addSymbol(fTargetNamespace);

            fNamespaceSupportRoot = new SchemaNamespaceSupport(fNamespaceSupport);

            //set namespace support
            fValidationContext.setNamespaceSupport(fNamespaceSupport);
            fValidationContext.setSymbolTable(symbolTable);
            // pass null as the schema document, so that the namespace
            // context is not popped.

            // don't return the attribute array yet!
            //attrChecker.returnAttrArray(schemaAttrs, null);
        }
    }

    // backup the current ns support, and use the one passed-in.
    // if no ns support is passed-in, use the one for <schema> element
    void backupNSSupport(SchemaNamespaceSupport nsSupport) {
        SchemaNamespaceSupportStack.push(fNamespaceSupport);
        if (nsSupport == null)
            nsSupport = fNamespaceSupportRoot;
        fNamespaceSupport = new SchemaNamespaceSupport(nsSupport);

        fValidationContext.setNamespaceSupport(fNamespaceSupport);
    }

    void restoreNSSupport() {
        fNamespaceSupport = (SchemaNamespaceSupport)SchemaNamespaceSupportStack.pop();
        fValidationContext.setNamespaceSupport(fNamespaceSupport);
    }

    // some Object methods
    public String toString() {
        StringBuffer buf = new StringBuffer();
        if (fTargetNamespace == null) {
            buf.append("no targetNamspace");
        }
        else {
            buf.append("targetNamespace is ");
            buf.append(fTargetNamespace);
        }
        Document doc = (fSchemaElement != null) ? fSchemaElement.getOwnerDocument() : null;
        if (doc instanceof org.apache.xerces.impl.xs.opti.SchemaDOM) {
            String documentURI = doc.getDocumentURI();
            if (documentURI != null && documentURI.length() > 0) {
                buf.append(" :: schemaLocation is ");
                buf.append(documentURI);
            }
        }
        return buf.toString();
    }

    public void addAllowedNS(String namespace) {
        fImportedNS.addElement(namespace == null ? "" : namespace);
    }
    
    public boolean isAllowedNS(String namespace) {
        return fImportedNS.contains(namespace == null ? "" : namespace);
    }
    
    // store whether we have reported an error about that this document
    // can't access components from the given namespace
    private Vector fReportedTNS = null;
    // check whether we need to report an error against the given uri.
    // if we have reported an error, then we don't need to report again;
    // otherwise we reported the error, and remember this fact.
    final boolean needReportTNSError(String uri) {
        if (fReportedTNS == null)
            fReportedTNS = new Vector();
        else if (fReportedTNS.contains(uri))
            return false;
        fReportedTNS.addElement(uri);
        return true;
    }

    // return the attributes on the schema element itself:
    Object [] getSchemaAttrs () {
        return fSchemaAttrs;
    }

    // deallocate the storage set aside for the schema element's
    // attributes
    void returnSchemaAttrs () {
        fAttrChecker.returnAttrArray (fSchemaAttrs, null);
        fSchemaAttrs = null;
    }
    
    // adds an annotation to the list of annotations
    void addAnnotation(XSAnnotationInfo info) {
        info.next = fAnnotations;
        fAnnotations = info;
    }
    
    // returns the list of annotations conatined in the
    // schema document or null if the document contained no annotations.
    XSAnnotationInfo getAnnotations() {
        return fAnnotations;
    }
    
    // removes reference to annotation list
    void removeAnnotations() {
        fAnnotations = null;
    }
    
} // XSDocumentInfo
