/*

 * 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

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package com.sun.tools.doclets.internal.toolkit.util;

import java.util.*;

import com.sun.javadoc.*;

import com.sun.tools.doclets.internal.toolkit.*;

/**

 * Provides methods for creating an array of class, method and

 * field names to be included as meta keywords in the HTML header

 * of class pages.  These keywords improve search results

 * on browsers that look for keywords.

 *

 *  <p><b>This is NOT part of any supported API.

 *  If you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 *

 * @author Doug Kramer

 */

public class MetaKeywords {

    /**

     * The global configuration information for this run.

     */

    private final Configuration configuration;

    private final Utils utils;

    /**

     * Constructor

     */

    public MetaKeywords(Configuration configuration) {

        this.configuration = configuration;

        this.utils = configuration.utils;

    }

    /**

     * Returns an array of strings where each element

     * is a class, method or field name.  This array is

     * used to create one meta keyword tag for each element.

     * Method parameter lists are converted to "()" and

     * overloads are combined.

     *

     * Constructors are not included because they have the same

     * name as the class, which is already included.

     * Nested class members are not included because their

     * definitions are on separate pages.

     */

    public String[] getMetaKeywords(ClassDoc classdoc) {

        ArrayList<String> results = new ArrayList<>();

        // Add field and method keywords only if -keywords option is used

        if( configuration.keywords ) {

            results.addAll(getClassKeyword(classdoc));

            results.addAll(getMemberKeywords(classdoc.fields()));

            results.addAll(getMemberKeywords(classdoc.methods()));

        }

        return results.toArray(new String[]{});

    }

    /**

     * Get the current class for a meta tag keyword, as the first

     * and only element of an array list.

     */

    protected ArrayList<String> getClassKeyword(ClassDoc classdoc) {

        String cltypelower = classdoc.isInterface() ? "interface" : "class";

        ArrayList<String> metakeywords = new ArrayList<>(1);

        metakeywords.add(classdoc.qualifiedName() + " " + cltypelower);

        return metakeywords;

    }

    /**

     * Get the package keywords.

     */

    public String[] getMetaKeywords(PackageDoc packageDoc) {

        if( configuration.keywords ) {

            String pkgName = utils.getPackageName(packageDoc);

            return new String[] { pkgName + " " + "package" };

        } else {

            return new String[] {};

        }

    }

    /**

     * Get the overview keywords.

     */

    public String[] getOverviewMetaKeywords(String title, String docTitle) {

        if( configuration.keywords ) {

            String windowOverview = configuration.getText(title);

            String[] metakeywords = { windowOverview };

            if (docTitle.length() > 0 ) {

                metakeywords[0] += ", " + docTitle;

            }

            return metakeywords;

        } else {

            return new String[] {};

        }

    }

    /**

     * Get members for meta tag keywords as an array,

     * where each member name is a string element of the array.

     * The parameter lists are not included in the keywords;

     * therefore all overloaded methods are combined.<br>

     * Example: getValue(Object) is returned in array as getValue()

     *

     * @param memberdocs  array of MemberDoc objects to be added to keywords

     */

    protected ArrayList<String> getMemberKeywords(MemberDoc[] memberdocs) {

        ArrayList<String> results = new ArrayList<>();

        String membername;

        for (MemberDoc memberdoc : memberdocs) {

            membername = memberdoc.name() + (memberdoc.isMethod() ? "()" : "");

            if (!results.contains(membername)) {

                results.add(membername);

            }

        }

        return results;

    }

}