/*
 * Copyright (c) 2005, 2006, 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;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.sun.codemodel.internal.CodeWriter;
import com.sun.codemodel.internal.JPackage;
import com.sun.codemodel.internal.writer.FileCodeWriter;
import com.sun.codemodel.internal.writer.PrologCodeWriter;
import com.sun.org.apache.xml.internal.resolver.CatalogManager;
import com.sun.org.apache.xml.internal.resolver.tools.CatalogResolver;
import com.sun.tools.internal.xjc.api.ClassNameAllocator;
import com.sun.tools.internal.xjc.api.SpecVersion;
import com.sun.tools.internal.xjc.generator.bean.field.FieldRendererFactory;
import com.sun.tools.internal.xjc.model.Model;
import com.sun.tools.internal.xjc.reader.Util;
import com.sun.xml.internal.bind.api.impl.NameConverter;

import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;

/**
 * Global options.
 *
 * <p>
 * This class stores invocation configuration for XJC.
 * The configuration in this class shoule be abstract enough so that
 * it could be parsed from both command-line or Ant.
 */
public class Options
{
    /** If "-debug" is specified. */
    public boolean debugMode;

    /** If the "-verbose" option is specified. */
    public boolean verbose;

    /** If the "-quiet" option is specified. */
    public boolean quiet;

    /** If the -readOnly option is specified. */
    public boolean readOnly;

    /** No file header comment (to be more friendly with diff.) */
    public boolean noFileHeader;

    /**
     * Check the source schemas with extra scrutiny.
     * The exact meaning depends on the schema language.
     */
    public boolean strictCheck =true;

    /**
     * If -explicit-annotation option is specified.
     * <p>
     * This generates code that works around issues specific to 1.4 runtime.
     */
    public boolean runtime14 = false;

    /**
     * If true, try to resolve name conflicts automatically by assigning mechanical numbers.
     */
    public boolean automaticNameConflictResolution = false;

    /**
     * strictly follow the compatibility rules and reject schemas that
     * contain features from App. E.2, use vendor binding extensions
     */
    public static final int STRICT = 1;
    /**
     * loosely follow the compatibility rules and allow the use of vendor
     * binding extensions
     */
    public static final int EXTENSION = 2;

    /**
     * this switch determines how carefully the compiler will follow
     * the compatibility rules in the spec. Either <code>STRICT</code>
     * or <code>EXTENSION</code>.
     */
    public int compatibilityMode = STRICT;

    public boolean isExtensionMode() {
        return compatibilityMode==EXTENSION;
    }

    /**
     * Generates output for the specified version of the runtime.
     */
    public SpecVersion target = SpecVersion.LATEST;

    private boolean is2_2 = true;

    public Options() {
        if (is2_2) {
            try {
                Class.forName("javax.xml.bind.JAXBPermission");
            } catch (ClassNotFoundException cnfe) {
                is2_2 = false;
            }
            if (!is2_2) {
                target = SpecVersion.V2_1;
            } else {
                target = SpecVersion.LATEST;
            }
        }
    }

    /**
     * Target directory when producing files.
     * <p>
     * This field is not used when XJC is driven through the XJC API.
     * Plugins that need to generate extra files should do so by using
     * {@link JPackage#addResourceFile(JResourceFile)}.
     */
    public File targetDir = new File(".");

    /**
     * Actually stores {@link CatalogResolver}, but the field
     * type is made to {@link EntityResolver} so that XJC can be
     * used even if resolver.jar is not available in the classpath.
     */
    public EntityResolver entityResolver = null;

    /**
     * Type of input schema language. One of the <code>SCHEMA_XXX</code>
     * constants.
     */
    private Language schemaLanguage = null;

    /**
     * The -p option that should control the default Java package that
     * will contain the generated code. Null if unspecified.
     */
    public String defaultPackage = null;

    /**
     * Similar to the -p option, but this one works with a lower priority,
     * and customizations overrides this. Used by JAX-RPC.
     */
    public String defaultPackage2 = null;

    /**
     * Input schema files as a list of {@link InputSource}s.
     */
    private final List<InputSource> grammars = new ArrayList<InputSource>();

    private final List<InputSource> bindFiles = new ArrayList<InputSource>();

    // Proxy setting.
    private String proxyHost = null;
    private String proxyPort = null;
    private String proxyUser = null;
    private String proxyPassword = null;

    /**
     * {@link Plugin}s that are enabled in this compilation.
     */
    public final List<Plugin> activePlugins = new ArrayList<Plugin>();

    /**
     * All discovered {@link Plugin}s.
     * This is lazily parsed, so that we can take '-cp' option into account.
     *
     * @see #getAllPlugins()
     */
    private List<Plugin> allPlugins;

    /**
     * Set of URIs that plug-ins recognize as extension bindings.
     */
    public final Set<String> pluginURIs = new HashSet<String>();

    /**
     * This allocator has the final say on deciding the class name.
     */
    public ClassNameAllocator classNameAllocator;

    /**
     * This switch controls whether or not xjc will generate package level annotations
     */
    public boolean packageLevelAnnotations = true;

    /**
     * This {@link FieldRendererFactory} determines how the fields are generated.
     */
    private FieldRendererFactory fieldRendererFactory = new FieldRendererFactory();
    /**
     * Used to detect if two {@link Plugin}s try to overwrite {@link #fieldRendererFactory}.
     */
    private Plugin fieldRendererFactoryOwner = null;

    /**
     * If this is non-null, we use this {@link NameConverter} over the one
     * given in the schema/binding.
     */
    private NameConverter nameConverter = null;
    /**
     * Used to detect if two {@link Plugin}s try to overwrite {@link #nameConverter}.
     */
    private Plugin nameConverterOwner = null;

    /**
     * Gets the active {@link FieldRendererFactory} that shall be used to build {@link Model}.
     *
     * @return always non-null.
     */
    public FieldRendererFactory getFieldRendererFactory() {
        return fieldRendererFactory;
    }

    /**
     * Sets the {@link FieldRendererFactory}.
     *
     * <p>
     * This method is for plugins to call to set a custom {@link FieldRendererFactory}.
     *
     * @param frf
     *      The {@link FieldRendererFactory} to be installed. Must not be null.
     * @param owner
     *      Identifies the plugin that owns this {@link FieldRendererFactory}.
     *      When two {@link Plugin}s try to call this method, this allows XJC
     *      to report it as a user-friendly error message.
     *
     * @throws BadCommandLineException
     *      If a conflit happens, this exception carries a user-friendly error
     *      message, indicating a conflict.
     */
    public void setFieldRendererFactory(FieldRendererFactory frf, Plugin owner) throws BadCommandLineException {
        // since this method is for plugins, make it bit more fool-proof than usual
        if(frf==null)
            throw new IllegalArgumentException();
        if(fieldRendererFactoryOwner!=null) {
            throw new BadCommandLineException(
                Messages.format(Messages.FIELD_RENDERER_CONFLICT,
                    fieldRendererFactoryOwner.getOptionName(),
                    owner.getOptionName() ));
        }
        this.fieldRendererFactoryOwner = owner;
        this.fieldRendererFactory = frf;
    }


    /**
     * Gets the active {@link NameConverter} that shall be used to build {@link Model}.
     *
     * @return can be null, in which case it's up to the binding.
     */
    public NameConverter getNameConverter() {
        return nameConverter;
    }

    /**
     * Sets the {@link NameConverter}.
     *
     * <p>
     * This method is for plugins to call to set a custom {@link NameConverter}.
     *
     * @param nc
     *      The {@link NameConverter} to be installed. Must not be null.
     * @param owner
     *      Identifies the plugin that owns this {@link NameConverter}.
     *      When two {@link Plugin}s try to call this method, this allows XJC
     *      to report it as a user-friendly error message.
     *
     * @throws BadCommandLineException
     *      If a conflit happens, this exception carries a user-friendly error
     *      message, indicating a conflict.
     */
    public void setNameConverter(NameConverter nc, Plugin owner) throws BadCommandLineException {
        // since this method is for plugins, make it bit more fool-proof than usual
        if(nc==null)
            throw new IllegalArgumentException();
        if(nameConverter!=null) {
            throw new BadCommandLineException(
                Messages.format(Messages.NAME_CONVERTER_CONFLICT,
                    nameConverterOwner.getOptionName(),
                    owner.getOptionName() ));
        }
        this.nameConverterOwner = owner;
        this.nameConverter = nc;
    }

    /**
     * Gets all the {@link Plugin}s discovered so far.
     *
     * <p>
     * A plugins are enumerated when this method is called for the first time,
     * by taking {@link #classpaths} into account. That means
     * "-cp plugin.jar" has to come before you specify options to enable it.
     */
    public List<Plugin> getAllPlugins() {
        if(allPlugins==null) {
            allPlugins = new ArrayList<Plugin>();
            ClassLoader ucl = getUserClassLoader(getClass().getClassLoader());
            for( Plugin aug : findServices(Plugin.class,ucl) )
                allPlugins.add(aug);
        }

        return allPlugins;
    }

    public Language getSchemaLanguage() {
        if( schemaLanguage==null)
            schemaLanguage = guessSchemaLanguage();
        return schemaLanguage;
    }
    public void setSchemaLanguage(Language _schemaLanguage) {
        this.schemaLanguage = _schemaLanguage;
    }

    /** Input schema files. */
    public InputSource[] getGrammars() {
        return grammars.toArray(new InputSource[grammars.size()]);
    }

    /**
     * Adds a new input schema.
     */
    public void addGrammar( InputSource is ) {
        grammars.add(absolutize(is));
    }

    private InputSource fileToInputSource( File source ) {
        try {
            String url = source.toURL().toExternalForm();
            return new InputSource(Util.escapeSpace(url));
        } catch (MalformedURLException e) {
            return new InputSource(source.getPath());
        }
    }

    public void addGrammar( File source ) {
        addGrammar(fileToInputSource(source));
    }

    /**
     * Recursively scan directories and add all XSD files in it.
     */
    public void addGrammarRecursive( File dir ) {
        addRecursive(dir,".xsd",grammars);
    }

    private  void addRecursive( File dir, String suffix, List<InputSource> result ) {
        File[] files = dir.listFiles();
        if(files==null)     return; // work defensively

        for( File f : files ) {
            if(f.isDirectory())
                addRecursive(f,suffix,result);
            else
            if(f.getPath().endsWith(suffix))
                result.add(absolutize(fileToInputSource(f)));
        }
    }


    private InputSource absolutize(InputSource is) {
        // absolutize all the system IDs in the input,
        // so that we can map system IDs to DOM trees.
        try {
            URL baseURL = new File(".").getCanonicalFile().toURL();
            is.setSystemId( new URL(baseURL,is.getSystemId()).toExternalForm() );
        } catch( IOException e ) {
            // ignore
        }
        return is;
    }


    /** Input external binding files. */
    public InputSource[] getBindFiles() {
        return bindFiles.toArray(new InputSource[bindFiles.size()]);
    }

    /**
     * Adds a new binding file.
     */
    public void addBindFile( InputSource is ) {
        bindFiles.add(absolutize(is));
    }

    /**
     * Adds a new binding file.
     */
    public void addBindFile( File bindFile ) {
        bindFiles.add(fileToInputSource(bindFile));
    }

    /**
     * Recursively scan directories and add all ".xjb" files in it.
     */
    public void addBindFileRecursive( File dir ) {
        addRecursive(dir,".xjb",bindFiles);
    }

    public final List<URL> classpaths = new ArrayList<URL>();
    /**
     * Gets a classLoader that can load classes specified via the
     * -classpath option.
     */
    public URLClassLoader getUserClassLoader( ClassLoader parent ) {
        return new URLClassLoader(
                classpaths.toArray(new URL[classpaths.size()]),parent);
    }


    /**
     * Parses an option <code>args[i]</code> and return
     * the number of tokens consumed.
     *
     * @return
     *      0 if the argument is not understood. Returning 0
     *      will let the caller report an error.
     * @exception BadCommandLineException
     *      If the callee wants to provide a custom message for an error.
     */
    public int parseArgument( String[] args, int i ) throws BadCommandLineException {
        if (args[i].equals("-classpath") || args[i].equals("-cp")) {
            String a = requireArgument(args[i], args, ++i);
            for (String p : a.split(File.pathSeparator)) {
                File file = new File(p);
                try {
                    classpaths.add(file.toURL());
                } catch (MalformedURLException e) {
                    throw new BadCommandLineException(
                        Messages.format(Messages.NOT_A_VALID_FILENAME,file),e);
                }
            }
            return 2;
        }
        if (args[i].equals("-d")) {
            targetDir = new File(requireArgument("-d",args,++i));
            if( !targetDir.exists() )
                throw new BadCommandLineException(
                    Messages.format(Messages.NON_EXISTENT_DIR,targetDir));
            return 2;
        }
        if (args[i].equals("-readOnly")) {
            readOnly = true;
            return 1;
        }
        if (args[i].equals("-p")) {
            defaultPackage = requireArgument("-p",args,++i);
            if(defaultPackage.length()==0) { // user specified default package
                // there won't be any package to annotate, so disable them
                // automatically as a usability feature
                packageLevelAnnotations = false;
            }
            return 2;
        }
        if (args[i].equals("-debug")) {
            debugMode = true;
            verbose = true;
            return 1;
        }
        if (args[i].equals("-nv")) {
            strictCheck = false;
            return 1;
        }
        if( args[i].equals("-npa")) {
            packageLevelAnnotations = false;
            return 1;
        }
        if( args[i].equals("-no-header")) {
            noFileHeader = true;
            return 1;
        }
        if (args[i].equals("-verbose")) {
            verbose = true;
            return 1;
        }
        if (args[i].equals("-quiet")) {
            quiet = true;
            return 1;
        }
        if (args[i].equals("-XexplicitAnnotation")) {
            runtime14 = true;
            return 1;
        }
        if (args[i].equals("-XautoNameResolution")) {
            automaticNameConflictResolution = true;
            return 1;
        }
        if (args[i].equals("-b")) {
            addFile(requireArgument("-b",args,++i),bindFiles,".xjb");
            return 2;
        }
        if (args[i].equals("-dtd")) {
            schemaLanguage = Language.DTD;
            return 1;
        }
        if (args[i].equals("-relaxng")) {
            schemaLanguage = Language.RELAXNG;
            return 1;
        }
        if (args[i].equals("-relaxng-compact")) {
            schemaLanguage = Language.RELAXNG_COMPACT;
            return 1;
        }
        if (args[i].equals("-xmlschema")) {
            schemaLanguage = Language.XMLSCHEMA;
            return 1;
        }
        if (args[i].equals("-wsdl")) {
            schemaLanguage = Language.WSDL;
            return 1;
        }
        if (args[i].equals("-extension")) {
            compatibilityMode = EXTENSION;
            return 1;
        }
        if (args[i].equals("-target")) {
            String token = requireArgument("-target",args,++i);
            target = SpecVersion.parse(token);
            if(target==null)
                throw new BadCommandLineException(Messages.format(Messages.ILLEGAL_TARGET_VERSION,token));
            return 2;
        }
        if (args[i].equals("-httpproxyfile")) {
            if (i == args.length - 1 || args[i + 1].startsWith("-")) {
                throw new BadCommandLineException(
                    Messages.format(Messages.MISSING_PROXYFILE));
            }

            File file = new File(args[++i]);
            if(!file.exists()) {
                throw new BadCommandLineException(
                    Messages.format(Messages.NO_SUCH_FILE,file));
            }

            try {
                BufferedReader in = new BufferedReader(new InputStreamReader(new FileInputStream(file),"UTF-8"));
                parseProxy(in.readLine());
                in.close();
            } catch (IOException e) {
                throw new BadCommandLineException(
                    Messages.format(Messages.FAILED_TO_PARSE,file,e.getMessage()),e);
            }

            return 2;
        }
        if (args[i].equals("-httpproxy")) {
            if (i == args.length - 1 || args[i + 1].startsWith("-")) {
                throw new BadCommandLineException(
                    Messages.format(Messages.MISSING_PROXY));
            }

            parseProxy(args[++i]);
            return 2;
        }
        if (args[i].equals("-host")) {
            proxyHost = requireArgument("-host",args,++i);
            return 2;
        }
        if (args[i].equals("-port")) {
            proxyPort = requireArgument("-port",args,++i);
            return 2;
        }
        if( args[i].equals("-catalog") ) {
            // use Sun's "XML Entity and URI Resolvers" by Norman Walsh
            // to resolve external entities.
            // http://www.sun.com/xml/developers/resolver/

            File catalogFile = new File(requireArgument("-catalog",args,++i));
            try {
                addCatalog(catalogFile);
            } catch (IOException e) {
                throw new BadCommandLineException(
                    Messages.format(Messages.FAILED_TO_PARSE,catalogFile,e.getMessage()),e);
            }
            return 2;
        }
        if (args[i].equals("-source")) {
            String version = requireArgument("-source",args,++i);
            //For source 1.0 the 1.0 Driver is loaded
            //Hence anything other than 2.0 is defaulted to
            //2.0
            if( !version.equals("2.0") && !version.equals("2.1") )
                throw new BadCommandLineException(
                    Messages.format(Messages.DEFAULT_VERSION));
            return 2;
        }
        if( args[i].equals("-Xtest-class-name-allocator") ) {
            classNameAllocator = new ClassNameAllocator() {
                public String assignClassName(String packageName, String className) {
                    System.out.printf("assignClassName(%s,%s)\n",packageName,className);
                    return className+"_Type";
                }
            };
            return 1;
        }

        // see if this is one of the extensions
        for( Plugin plugin : getAllPlugins() ) {
            try {
                if( ('-'+plugin.getOptionName()).equals(args[i]) ) {
                    activePlugins.add(plugin);
                    plugin.onActivated(this);
                    pluginURIs.addAll(plugin.getCustomizationURIs());

                    // give the plugin a chance to parse arguments to this option.
                    // this is new in 2.1, and due to the backward compatibility reason,
                    // if plugin didn't understand it, we still return 1 to indicate
                    // that this option is consumed.
                    int r = plugin.parseArgument(this,args,i);
                    if(r!=0)
                        return r;
                    else
                        return 1;
                }

                int r = plugin.parseArgument(this,args,i);
                if(r!=0)    return r;
            } catch (IOException e) {
                throw new BadCommandLineException(e.getMessage(),e);
            }
        }

        return 0;   // unrecognized
    }

    private void parseProxy(String text) throws BadCommandLineException {
        // syntax is [user[:password]@]proxyHost:proxyPort
        String token = "([^@:]+)";
        Pattern p = Pattern.compile("(?:"+token+"(?:\\:"+token+")?\\@)?"+token+"(?:\\:"+token+")");

        Matcher matcher = p.matcher(text);
        if(!matcher.matches())
            throw new BadCommandLineException(Messages.format(Messages.ILLEGAL_PROXY,text));

        proxyUser = matcher.group(1);
        proxyPassword = matcher.group(2);
        proxyHost = matcher.group(3);
        proxyPort = matcher.group(4);
        try {
            Integer.valueOf(proxyPort);
        } catch (NumberFormatException e) {
            throw new BadCommandLineException(Messages.format(Messages.ILLEGAL_PROXY,text));
        }
    }

    /**
     * Obtains an operand and reports an error if it's not there.
     */
    public String requireArgument(String optionName, String[] args, int i) throws BadCommandLineException {
        if (i == args.length || args[i].startsWith("-")) {
            throw new BadCommandLineException(
                Messages.format(Messages.MISSING_OPERAND,optionName));
        }
        return args[i];
    }

    /**
     * Parses a token to a file (or a set of files)
     * and add them as {@link InputSource} to the specified list.
     *
     * @param suffix
     *      If the given token is a directory name, we do a recusive search
     *      and find all files that have the given suffix.
     */
    private void addFile(String name, List<InputSource> target, String suffix) throws BadCommandLineException {
        Object src;
        try {
            src = Util.getFileOrURL(name);
        } catch (IOException e) {
            throw new BadCommandLineException(
                Messages.format(Messages.NOT_A_FILE_NOR_URL,name));
        }
        if(src instanceof URL) {
            target.add(absolutize(new InputSource(Util.escapeSpace(((URL)src).toExternalForm()))));
        } else {
            File fsrc = (File)src;
            if(fsrc.isDirectory()) {
                addRecursive(fsrc,suffix,target);
            } else {
                target.add(absolutize(fileToInputSource(fsrc)));
            }
        }
    }

    /**
     * Adds a new catalog file.
     */
    public void addCatalog(File catalogFile) throws IOException {
        if(entityResolver==null) {
            CatalogManager.getStaticManager().setIgnoreMissingProperties(true);
            entityResolver = new CatalogResolver(true);
        }
        ((CatalogResolver)entityResolver).getCatalog().parseCatalog(catalogFile.getPath());
    }

    /**
     * Parses arguments and fill fields of this object.
     *
     * @exception BadCommandLineException
     *      thrown when there's a problem in the command-line arguments
     */
    public void parseArguments( String[] args ) throws BadCommandLineException {

        for (int i = 0; i < args.length; i++) {
            if(args[i].length()==0)
                throw new BadCommandLineException();
            if (args[i].charAt(0) == '-') {
                int j = parseArgument(args,i);
                if(j==0)
                    throw new BadCommandLineException(
                        Messages.format(Messages.UNRECOGNIZED_PARAMETER, args[i]));
                i += (j-1);
            } else {
                if(args[i].endsWith(".jar"))
                    scanEpisodeFile(new File(args[i]));
                else
                    addFile(args[i],grammars,".xsd");
            }
        }

        // configure proxy
        if (proxyHost != null || proxyPort != null) {
            if (proxyHost != null && proxyPort != null) {
                System.setProperty("http.proxyHost", proxyHost);
                System.setProperty("http.proxyPort", proxyPort);
                System.setProperty("https.proxyHost", proxyHost);
                System.setProperty("https.proxyPort", proxyPort);
            } else if (proxyHost == null) {
                throw new BadCommandLineException(
                    Messages.format(Messages.MISSING_PROXYHOST));
            } else {
                throw new BadCommandLineException(
                    Messages.format(Messages.MISSING_PROXYPORT));
            }
            if(proxyUser!=null)
                System.setProperty("http.proxyUser", proxyUser);
            if(proxyPassword!=null)
                System.setProperty("http.proxyPassword", proxyPassword);

        }

        if (grammars.size() == 0)
            throw new BadCommandLineException(
                Messages.format(Messages.MISSING_GRAMMAR));

        if( schemaLanguage==null )
            schemaLanguage = guessSchemaLanguage();

//        if(target==SpecVersion.V2_2 && !isExtensionMode())
//            throw new BadCommandLineException(
//                "Currently 2.2 is still not finalized yet, so using it requires the -extension switch." +
//                "NOTE THAT 2.2 SPEC MAY CHANGE BEFORE IT BECOMES FINAL.");

        if(pluginLoadFailure!=null)
            throw new BadCommandLineException(
                Messages.format(Messages.PLUGIN_LOAD_FAILURE,pluginLoadFailure));
    }

    /**
     * Finds the <tt>META-INF/sun-jaxb.episode</tt> file to add as a binding customization.
     */
    public void scanEpisodeFile(File jar) throws BadCommandLineException {
        try {
            URLClassLoader ucl = new URLClassLoader(new URL[]{jar.toURL()});
            Enumeration<URL> resources = ucl.findResources("META-INF/sun-jaxb.episode");
            while (resources.hasMoreElements()) {
                URL url = resources.nextElement();
                addBindFile(new InputSource(url.toExternalForm()));
            }
        } catch (IOException e) {
            throw new BadCommandLineException(
                    Messages.format(Messages.FAILED_TO_LOAD,jar,e.getMessage()), e);
        }
    }


    /**
     * Guesses the schema language.
     */
    public Language guessSchemaLanguage() {

        // otherwise, use the file extension.
        // not a good solution, but very easy.
        if ((grammars != null) && (grammars.size() > 0)) {
            String name = grammars.get(0).getSystemId().toLowerCase();

            if (name.endsWith(".rng"))
                return Language.RELAXNG;
            if (name.endsWith(".rnc"))
                return Language.RELAXNG_COMPACT;
            if (name.endsWith(".dtd"))
                return Language.DTD;
            if (name.endsWith(".wsdl"))
                return Language.WSDL;
        }

        // by default, assume XML Schema
        return Language.XMLSCHEMA;
    }

    /**
     * Creates a configured CodeWriter that produces files into the specified directory.
     */
    public CodeWriter createCodeWriter() throws IOException {
        return createCodeWriter(new FileCodeWriter( targetDir, readOnly ));
    }

    /**
     * Creates a configured CodeWriter that produces files into the specified directory.
     */
    public CodeWriter createCodeWriter( CodeWriter core ) {
        if(noFileHeader)
            return core;

        return new PrologCodeWriter( core,getPrologComment() );
    }

    /**
     * Gets the string suitable to be used as the prolog comment baked into artifacts.
     * This is the string like "This file was generated by the JAXB RI on YYYY/mm/dd..."
     */
    public String getPrologComment() {
        // generate format syntax: <date> 'at' <time>
        String format =
            Messages.format(Messages.DATE_FORMAT)
                + " '"
                + Messages.format(Messages.AT)
                + "' "
                + Messages.format(Messages.TIME_FORMAT);
        SimpleDateFormat dateFormat = new SimpleDateFormat(format);

        return Messages.format(
            Messages.FILE_PROLOG_COMMENT,
            dateFormat.format(new Date()));
    }

    /**
     * If a plugin failed to load, report.
     */
    private static String pluginLoadFailure;

    /**
     * Looks for all "META-INF/services/[className]" files and
     * create one instance for each class name found inside this file.
     */
    private static <T> T[] findServices( Class<T> clazz, ClassLoader classLoader ) {
        // if true, print debug output
        final boolean debug = com.sun.tools.internal.xjc.util.Util.getSystemProperty(Options.class,"findServices")!=null;

        // if we are running on Mustang or Dolphin, use ServiceLoader
        // so that we can take advantage of JSR-277 module system.
        try {
            Class<?> serviceLoader = Class.forName("java.util.ServiceLoader");
            if(debug)
                System.out.println("Using java.util.ServiceLoader");
            Iterable<T> itr = (Iterable<T>)serviceLoader.getMethod("load",Class.class,ClassLoader.class).invoke(null,clazz,classLoader);
            List<T> r = new ArrayList<T>();
            for (T t : itr)
                r.add(t);
            return r.toArray((T[])Array.newInstance(clazz,r.size()));
        } catch (ClassNotFoundException e) {
            // fall through
        } catch (IllegalAccessException e) {
            Error x = new IllegalAccessError();
            x.initCause(e);
            throw x;
        } catch (InvocationTargetException e) {
            Throwable x = e.getTargetException();
            if (x instanceof RuntimeException)
                throw (RuntimeException) x;
            if (x instanceof Error)
                throw (Error) x;
            throw new Error(x);
        } catch (NoSuchMethodException e) {
            Error x = new NoSuchMethodError();
            x.initCause(e);
            throw x;
        }

        String serviceId = "META-INF/services/" + clazz.getName();

        // used to avoid creating the same instance twice
        Set<String> classNames = new HashSet<String>();

        if(debug) {
            System.out.println("Looking for "+serviceId+" for add-ons");
        }

        // try to find services in CLASSPATH
        try {
            Enumeration<URL> e = classLoader.getResources(serviceId);
            if(e==null) return (T[])Array.newInstance(clazz,0);

            ArrayList<T> a = new ArrayList<T>();
            while(e.hasMoreElements()) {
                URL url = e.nextElement();
                BufferedReader reader=null;

                if(debug) {
                    System.out.println("Checking "+url+" for an add-on");
                }

                try {
                    reader = new BufferedReader(new InputStreamReader(url.openStream()));
                    String impl;
                    while((impl = reader.readLine())!=null ) {
                        // try to instanciate the object
                        impl = impl.trim();
                        if(classNames.add(impl)) {
                            Class implClass = classLoader.loadClass(impl);
                            if(!clazz.isAssignableFrom(implClass)) {
                                pluginLoadFailure = impl+" is not a subclass of "+clazz+". Skipping";
                                if(debug)
                                    System.out.println(pluginLoadFailure);
                                continue;
                            }
                            if(debug) {
                                System.out.println("Attempting to instanciate "+impl);
                            }
                            a.add(clazz.cast(implClass.newInstance()));
                        }
                    }
                    reader.close();
                } catch( Exception ex ) {
                    // let it go.
                    StringWriter w = new StringWriter();
                    ex.printStackTrace(new PrintWriter(w));
                    pluginLoadFailure = w.toString();
                    if(debug) {
                        System.out.println(pluginLoadFailure);
                    }
                    if( reader!=null ) {
                        try {
                            reader.close();
                        } catch( IOException ex2 ) {
                            // ignore
                        }
                    }
                }
            }

            return a.toArray((T[])Array.newInstance(clazz,a.size()));
        } catch( Throwable e ) {
            // ignore any error
            StringWriter w = new StringWriter();
            e.printStackTrace(new PrintWriter(w));
            pluginLoadFailure = w.toString();
            if(debug) {
                System.out.println(pluginLoadFailure);
            }
            return (T[])Array.newInstance(clazz,0);
        }
    }

    // this is a convenient place to expose the build version to xjc plugins
    public static String getBuildID() {
        return Messages.format(Messages.BUILD_ID);
    }
}
