/*
 * 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.tuscany.tools.java2wsdl.generate;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;

import javax.xml.namespace.QName;

import org.apache.axis2.description.java2wsdl.bytecode.MethodTable;
import org.apache.ws.commons.schema.XmlSchema;
import org.apache.ws.commons.schema.XmlSchemaCollection;
import org.apache.ws.commons.schema.XmlSchemaComplexType;
import org.apache.ws.commons.schema.XmlSchemaElement;
import org.apache.ws.commons.schema.XmlSchemaForm;
import org.apache.ws.commons.schema.XmlSchemaImport;
import org.apache.ws.commons.schema.XmlSchemaInclude;
import org.apache.ws.commons.schema.XmlSchemaSequence;
import org.apache.ws.commons.schema.utils.NamespaceMap;
import org.codehaus.jam.JClass;
import org.codehaus.jam.JMethod;
import org.codehaus.jam.JParameter;
import org.codehaus.jam.JamClassIterator;
import org.codehaus.jam.JamService;
import org.codehaus.jam.JamServiceFactory;
import org.codehaus.jam.JamServiceParams;

public class TuscanyWSDLTypesGenerator implements TuscanyJava2WSDLConstants {
    public static final String NAME_SPACE_PREFIX = "stn_";

    public static final String PERIOD_SEPARATOR = ".";

    private static int prefixCount = 1;

    protected GenerationParameters generationParams;

    protected Hashtable targetNamespacePrefixMap = new Hashtable();

    protected Hashtable schemaMap = new Hashtable();

    protected XmlSchemaCollection xmlSchemaCollection = new XmlSchemaCollection();

    private TuscanyTypeTable typeTable = new TuscanyTypeTable();

    protected SchemaBuilder schemaBuilder = null;

    protected Map schemaLocationMap = null;

    // to keep loaded method using JAM
    private JMethod methods[];

    // to store byte code method using Axis 1.x codes
    private MethodTable methodTable;

    private Class clazz;

    private ArrayList excludeMethods = new ArrayList();

    boolean alreadyPrintedArrayWarningMessage = false;

    public TuscanyWSDLTypesGenerator(GenerationParameters genParams) throws Exception {
        this.generationParams = genParams;

        String inputClassName = generationParams.getSourceClassName();

        try {
            clazz = Class.forName(inputClassName, true, generationParams.getClassLoader());
        } catch (ClassNotFoundException cfne) {
            printInputSourceClassNotFoundMessage(inputClassName);
            throw new IllegalArgumentException("Input className not found:" + inputClassName, cfne);
        }

        methodTable = new MethodTable(clazz);

        initializeSchemaMap(generationParams.getSchemaTargetNamespace(), generationParams
            .getSchemaTargetNamespacePrefix());

        this.schemaLocationMap = generationParams.getSchemaLocationMap();
        schemaBuilder =
            new SchemaBuilder(xmlSchemaCollection, schemaMap, targetNamespacePrefixMap, typeTable, generationParams
                .getAttrFormDefault(), generationParams.getElementFormDefault(), generationParams
                .getSchemaLocationMap(), generationParams.getClassLoader(), generationParams.getFactoryClassNames());
    }

    /**
     * Generates schema for all the parameters in method. First generates schema
     * for all different parameter type and later refers to them.
     * 
     * @return Returns XmlSchema.
     * @throws Exception
     */
    public Collection buildWSDLTypes() throws Exception {
        JamServiceFactory factory = JamServiceFactory.getInstance();
        JamServiceParams jam_service_parms = factory.createServiceParams();
        // setting the classLoder
        // jam_service_parms.setParentClassLoader(factory.createJamClassLoader(classLoader));
        // it can possible to add the classLoader as well
        jam_service_parms.addClassLoader(generationParams.getClassLoader());
        jam_service_parms.includeClass(generationParams.getSourceClassName());

        for (int count = 0; count < generationParams.getExtraClasses().size(); ++count) {
            jam_service_parms.includeClass((String)generationParams.getExtraClasses().get(count));
        }

        JamService service = factory.createService(jam_service_parms);
        QName extraSchemaTypeName = null;
        JamClassIterator jClassIter = service.getClasses();
        // all most all the time the ittr will have only one class in it
        while (jClassIter.hasNext()) {
            JClass jclass = (JClass)jClassIter.next();
            // serviceName = jclass.getSimpleName();
            // todo in the future , when we support annotation we can use this
            // JAnnotation[] annotations = jclass.getAnnotations();

            if (jclass.getQualifiedName().equals(generationParams.getSourceClassName())) {
                /**
                 * Schema generation done in two stage 1. Load all the methods
                 * and create type for methods parameters (if the parameters are
                 * Bean then it will create Complex types for those , and if the
                 * parameters are simple type which describe in SimpleTypeTable
                 * nothing will happen) 2. In the next stage for all the methods
                 * messages and port types will be created
                 */
                methods = jclass.getDeclaredMethods();
                // short the elements in the array
                Arrays.sort(methods);

                // since we do not support overload
                HashMap uniqueMethods = new HashMap();
                XmlSchemaComplexType methodSchemaType;
                XmlSchemaSequence sequence = null;

                for (int i = 0; i < methods.length; i++) {
                    JMethod jMethod = methods[i];

                    String methodName = methods[i].getSimpleName();
                    // no need to think about this method , since that is system
                    // config method
                    if (excludeMethods.contains(jMethod.getSimpleName())) {
                        continue;
                    }

                    if (uniqueMethods.get(jMethod.getSimpleName()) != null) {
                        throw new Exception(" Sorry we don't support methods overloading !!!! ");
                    }

                    if (!jMethod.isPublic()) {
                        // no need to generate Schema for non public methods
                        continue;
                    }
                    uniqueMethods.put(jMethod.getSimpleName(), jMethod);
                    // create the schema type for the method wrapper

                    uniqueMethods.put(jMethod.getSimpleName(), jMethod);
                    JParameter[] paras = jMethod.getParameters();
                    String parameterNames[] = null;
                    // better to handle void types too
                    parameterNames = methodTable.getParameterNames(methodName);
                    sequence = new XmlSchemaSequence();

                    methodSchemaType = createSchemaTypeForMethodPart(jMethod.getSimpleName());
                    methodSchemaType.setParticle(sequence);

                    for (int j = 0; j < paras.length; j++) {
                        JParameter methodParameter = paras[j];
                        JClass paraType = methodParameter.getType();
                        generateSchemaForType(sequence, paraType, (parameterNames != null && parameterNames[j] != null)
                            ? parameterNames[j] : methodParameter.getSimpleName());
                    }
                    // for its return type
                    JClass returnType = jMethod.getReturnType();

                    // better to handle void types too
                    methodSchemaType = createSchemaTypeForMethodPart(jMethod.getSimpleName() + RESPONSE);
                    sequence = new XmlSchemaSequence();
                    methodSchemaType.setParticle(sequence);
                    generateSchemaForType(sequence, returnType, "return");
                }
            } else {
                // generate the schema type for extra classes
                extraSchemaTypeName = typeTable.getSimpleSchemaTypeName(jclass.getQualifiedName());
                if (extraSchemaTypeName == null) {
                    extraSchemaTypeName = schemaBuilder.generateSchema(jclass);
                }
            }
        }
        return schemaMap.values();
    }

    private QName generateSchemaForType(XmlSchemaSequence sequence, JClass type, String partName) throws Exception {
        if (type.isVoidType()) {
            return null;
        }
        boolean isArrayType = type.isArrayType();
        if (isArrayType) {
            type = type.getArrayComponentType();
        }

        String classTypeName = type.getQualifiedName();

        QName schemaTypeName = typeTable.getSimpleSchemaTypeName(classTypeName);
        if (schemaTypeName == null) {
            schemaTypeName = schemaBuilder.generateSchema(type);
            addContentToMethodSchemaType(sequence, schemaTypeName, partName, type.isArrayType());
            addImportORInclude((XmlSchema)schemaMap.get(generationParams.getSchemaTargetNamespace()), schemaTypeName);

        } else {
            addContentToMethodSchemaType(sequence, schemaTypeName, partName, type.isArrayType());
        }

        return schemaTypeName;
    }

    private void addContentToMethodSchemaType(XmlSchemaSequence sequence,
                                              QName schemaTypeName,
                                              String paraName,
                                              boolean isArray) {
        XmlSchemaElement elt1 = new XmlSchemaElement();
        elt1.setName(paraName);
        elt1.setSchemaTypeName(schemaTypeName);
        sequence.getItems().add(elt1);

        if (isArray) {
            // FIXME: lresende to check this
            if (!alreadyPrintedArrayWarningMessage) {
                alreadyPrintedArrayWarningMessage = true;
                System.out.println("Warning!: Array type detected as Java method parameter. The WSDL");
                System.out.println("will be generated anyway in spite of the fact that round-trip (WSDL2Java)");
                System.out.println("may not be handled in the expected manner.  There may be runtime issues as ");
                System.out.println("well as array types are not necessarily supported yet.");
                System.out.println("");
            }
            elt1.setMaxOccurs(Long.MAX_VALUE);
            elt1.setMinOccurs(0);
        }
    }

    private XmlSchemaComplexType createSchemaTypeForMethodPart(String localPartName) throws Exception {
        XmlSchema xmlSchema = (XmlSchema)schemaMap.get(generationParams.getSchemaTargetNamespace());
        QName elementName =
            new QName(generationParams.getSchemaTargetNamespace(), localPartName, generationParams
                .getSchemaTargetNamespacePrefix());
        XmlSchemaComplexType complexType = new XmlSchemaComplexType(xmlSchema);

        XmlSchemaElement globalElement = new XmlSchemaElement();
        globalElement.setSchemaType(complexType);
        globalElement.setName(localPartName);
        globalElement.setQName(elementName);

        xmlSchema.getItems().add(globalElement);
        xmlSchema.getElements().add(elementName, globalElement);

        typeTable.addComplexSchemaType(generationParams.getSchemaTargetNamespace(),
                                       globalElement.getName(),
                                       elementName);

        return complexType;
    }

    public TuscanyTypeTable getTypeTable() {
        return typeTable;
    }

    public JMethod[] getMethods() {
        return methods;
    }

    private String generatePrefix() {
        return NAME_SPACE_PREFIX + prefixCount++;
    }

    public void setExcludeMethods(ArrayList excludeMethods) {
        this.excludeMethods = excludeMethods;
    }

    private void initializeSchemaMap(String targetNamespace, String targetNamespacePrefix) {
        XmlSchema xmlSchema = new XmlSchema(targetNamespace, xmlSchemaCollection);
        xmlSchema.setAttributeFormDefault(getAttrFormDefaultSetting());
        xmlSchema.setElementFormDefault(getElementFormDefaultSetting());

        targetNamespacePrefixMap.put(targetNamespace, targetNamespacePrefix);
        schemaMap.put(targetNamespace, xmlSchema);

        NamespaceMap prefixmap = new NamespaceMap();
        prefixmap.put(TuscanyTypeTable.XS_URI_PREFIX, TuscanyTypeTable.XML_SCHEMA_URI);
        prefixmap.put(targetNamespacePrefix, targetNamespace);
        xmlSchema.setNamespaceContext(prefixmap);
    }

    /*
     * Adds to 'xmlSchema' an import or include of the XMLSchema containing
     * 'schemaTypeName'
     */
    private void addImportORInclude(XmlSchema xmlSchema, QName schemaTypeName) {
        // decide whether there must be an import or an include
        if (xmlSchema.getTargetNamespace().equals(schemaTypeName.getNamespaceURI())) {
            XmlSchema containingSchema = (XmlSchema)schemaMap.get(schemaTypeName.getNamespaceURI());
            // if the type is not defined in the Schema then include
            if (containingSchema.getTypeByName(schemaTypeName) == null) {
                String schemaLocation = null;
                // This looked backwards so I flipped it
                if ((schemaLocation = (String)schemaLocationMap.get(schemaTypeName.getNamespaceURI())) != null) {
                    schemaLocation = DEFAULT_SCHEMA_LOCATION;
                }

                XmlSchemaInclude includeElement = new XmlSchemaInclude();
                includeElement.setSchemaLocation(schemaLocation);

                if (!xmlSchema.getIncludes().contains(includeElement)) {
                    xmlSchema.getIncludes().add(includeElement);
                    // Add this so it will be serialized
                    xmlSchema.getItems().add(includeElement);
                }
            }
        } else {
            if (!((NamespaceMap)xmlSchema.getNamespaceContext()).values().contains(schemaTypeName.getNamespaceURI())) {
                XmlSchemaImport importElement = new XmlSchemaImport();
                importElement.setNamespace(schemaTypeName.getNamespaceURI());

                // Add schemaLocation on imports
                String schemaLocation = (String)schemaLocationMap.get(schemaTypeName.getNamespaceURI());
                importElement.setSchemaLocation(schemaLocation);
                xmlSchema.getItems().add(importElement);
                ((NamespaceMap)xmlSchema.getNamespaceContext()).put(generatePrefix(), schemaTypeName.getNamespaceURI());
            }
        }
    }

    private XmlSchemaForm getAttrFormDefaultSetting() {
        if (FORM_DEFAULT_UNQUALIFIED.equals(generationParams.getAttrFormDefault())) {
            return new XmlSchemaForm(XmlSchemaForm.UNQUALIFIED);
        } else {
            return new XmlSchemaForm(XmlSchemaForm.QUALIFIED);
        }
    }

    private XmlSchemaForm getElementFormDefaultSetting() {
        if (FORM_DEFAULT_UNQUALIFIED.equals(generationParams.getElementFormDefault())) {
            return new XmlSchemaForm(XmlSchemaForm.UNQUALIFIED);
        } else {
            return new XmlSchemaForm(XmlSchemaForm.QUALIFIED);
        }
    }

    private void printInputSourceClassNotFoundMessage(String inputClassName) {
        System.out.println("ERROR!!:  The input class: " + inputClassName + " could not be found.");
        System.out.println("Please check the value you provided for the -cp <class path uri> option.");
        System.out.println("");
    }
}