/*
 * Copyright (c) 1998, 2020, 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 jdk.javadoc.internal.doclets.toolkit.util;

import java.util.*;

import javax.lang.model.element.ModuleElement;
import javax.lang.model.element.PackageElement;

import jdk.javadoc.internal.doclets.toolkit.BaseConfiguration;
import jdk.javadoc.internal.doclets.toolkit.Messages;


Process and manage grouping of elements, as specified by "-group" option on
the command line.

For example, if user has used -group option as
-group "Core Packages" "java.*" -group "CORBA Packages" "org.omg.*", then
the packages specified on the command line will be grouped according to their
names starting with either "java." or "org.omg.". All the other packages
which do not fall in the user given groups, are grouped in default group,
named as either "Other Packages" or "Packages" depending upon if "-group"
option used or not at all used respectively.


Also the packages are grouped according to the longest possible match of
their names with the grouping information provided. For example, if there
are two groups, like -group "Lang" "java.lang" and -group "Core" "java.*",
will put the package java.lang in the group "Lang" and not in group "Core".

 
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.
/**
 * Process and manage grouping of elements, as specified by "-group" option on
 * the command line.
 * <p>
 * For example, if user has used -group option as
 * -group "Core Packages" "java.*" -group "CORBA Packages" "org.omg.*", then
 * the packages specified on the command line will be grouped according to their
 * names starting with either "java." or "org.omg.". All the other packages
 * which do not fall in the user given groups, are grouped in default group,
 * named as either "Other Packages" or "Packages" depending upon if "-group"
 * option used or not at all used respectively.
 * </p>
 * <p>
 * Also the packages are grouped according to the longest possible match of
 * their names with the grouping information provided. For example, if there
 * are two groups, like -group "Lang" "java.lang" and -group "Core" "java.*",
 * will put the package java.lang in the group "Lang" and not in group "Core".
 * </p>
 *
 *  <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>
 */
public class Group {

    
Map of regular expressions with the corresponding group name.
/**
     * Map of regular expressions with the corresponding group name.
     */
    private Map<String,String> regExpGroupMap = new HashMap<>();

    
List of regular expressions sorted according to the length. Regular
expression with longest length will be first in the sorted order.
/**
     * List of regular expressions sorted according to the length. Regular
     * expression with longest length will be first in the sorted order.
     */
    private List<String> sortedRegExpList = new ArrayList<>();

    
List of group names in the same order as given on the command line.
/**
     * List of group names in the same order as given on the command line.
     */
    private List<String> groupList = new ArrayList<>();

    
Map of non-regular expressions(possible package or module names) with the
corresponding group name.
/**
     * Map of non-regular expressions(possible package or module names) with the
     * corresponding group name.
     */
    private Map<String,String> elementNameGroupMap = new HashMap<>();

    
The global configuration information for this run.
/**
     * The global configuration information for this run.
     */
    private final BaseConfiguration configuration;
    private Messages messages;

    
Since we need to sort the keys in the reverse order(longest key first),
the compare method in the implementing class is doing the reverse
comparison.
/**
     * Since we need to sort the keys in the reverse order(longest key first),
     * the compare method in the implementing class is doing the reverse
     * comparison.
     */
    private static class MapKeyComparator implements Comparator<String> {
        @Override
        public int compare(String key1, String key2) {
            return key2.length() - key1.length();
        }
    }

    public Group(BaseConfiguration configuration) {
        this.configuration = configuration;
        messages = configuration.getMessages();
    }

    
Depending upon the format of the module name provided in the "-group"
option, generate two separate maps. There will be a map for mapping
regular expression(only meta character allowed is '*' and that is at the
end of the regular expression) on to the group name. And another map
for mapping (possible) module names(if the name format doesn't contain
meta character '*', then it is assumed to be a module name) on to the
group name. This will also sort all the regular expressions found in the
reverse order of their lengths, i.e. longest regular expression will be
first in the sorted list.
Params:
groupname –       The name of the group from -group option.
moduleNameFormList – List of the module name formats./**
     * Depending upon the format of the module name provided in the "-group"
     * option, generate two separate maps. There will be a map for mapping
     * regular expression(only meta character allowed is '*' and that is at the
     * end of the regular expression) on to the group name. And another map
     * for mapping (possible) module names(if the name format doesn't contain
     * meta character '*', then it is assumed to be a module name) on to the
     * group name. This will also sort all the regular expressions found in the
     * reverse order of their lengths, i.e. longest regular expression will be
     * first in the sorted list.
     *
     * @param groupname       The name of the group from -group option.
     * @param moduleNameFormList List of the module name formats.
     */
    public boolean checkModuleGroups(String groupname, String moduleNameFormList) {
        String[] mdlPatterns = moduleNameFormList.split(":");
        if (groupList.contains(groupname)) {
            initMessages();
            messages.warning("doclet.Groupname_already_used", groupname);
            return false;
        }
        groupList.add(groupname);
        for (String mdlPattern : mdlPatterns) {
            if (mdlPattern.length() == 0) {
                initMessages();
                messages.warning("doclet.Error_in_grouplist", groupname, moduleNameFormList);
                return false;
            }
            if (mdlPattern.endsWith("*")) {
                mdlPattern = mdlPattern.substring(0, mdlPattern.length() - 1);
                if (foundGroupFormat(regExpGroupMap, mdlPattern)) {
                    return false;
                }
                regExpGroupMap.put(mdlPattern, groupname);
                sortedRegExpList.add(mdlPattern);
            } else {
                if (foundGroupFormat(elementNameGroupMap, mdlPattern)) {
                    return false;
                }
                elementNameGroupMap.put(mdlPattern, groupname);
            }
        }
        Collections.sort(sortedRegExpList, new MapKeyComparator());
        return true;
    }

    
Depending upon the format of the package name provided in the "-group"
option, generate two separate maps. There will be a map for mapping
regular expression(only meta character allowed is '*' and that is at the
end of the regular expression) on to the group name. And another map
for mapping (possible) package names(if the name format doesn't contain
meta character '*', then it is assumed to be a package name) on to the
group name. This will also sort all the regular expressions found in the
reverse order of their lengths, i.e. longest regular expression will be
first in the sorted list.
Params:
groupname –       The name of the group from -group option.
pkgNameFormList – List of the package name formats./**
     * Depending upon the format of the package name provided in the "-group"
     * option, generate two separate maps. There will be a map for mapping
     * regular expression(only meta character allowed is '*' and that is at the
     * end of the regular expression) on to the group name. And another map
     * for mapping (possible) package names(if the name format doesn't contain
     * meta character '*', then it is assumed to be a package name) on to the
     * group name. This will also sort all the regular expressions found in the
     * reverse order of their lengths, i.e. longest regular expression will be
     * first in the sorted list.
     *
     * @param groupname       The name of the group from -group option.
     * @param pkgNameFormList List of the package name formats.
     */
    public boolean checkPackageGroups(String groupname, String pkgNameFormList) {
        String[] pkgPatterns = pkgNameFormList.split(":");
        if (groupList.contains(groupname)) {
            initMessages();
            messages.warning("doclet.Groupname_already_used", groupname);
            return false;
        }
        groupList.add(groupname);
        for (String pkgPattern : pkgPatterns) {
            if (pkgPattern.length() == 0) {
                initMessages();
                messages.warning("doclet.Error_in_grouplist", groupname, pkgNameFormList);
                return false;
            }
            if (pkgPattern.endsWith("*")) {
                pkgPattern = pkgPattern.substring(0, pkgPattern.length() - 1);
                if (foundGroupFormat(regExpGroupMap, pkgPattern)) {
                    return false;
                }
                regExpGroupMap.put(pkgPattern, groupname);
                sortedRegExpList.add(pkgPattern);
            } else {
                if (foundGroupFormat(elementNameGroupMap, pkgPattern)) {
                    return false;
                }
                elementNameGroupMap.put(pkgPattern, groupname);
            }
        }
        Collections.sort(sortedRegExpList, new MapKeyComparator());
        return true;
    }

    // Lazy init of the messages for now, because Group is created
    // in BaseConfiguration before configuration is fully initialized.
    private void initMessages() {
        if (messages == null) {
            messages = configuration.getMessages();
        }
    }

    
Search if the given map has the given element format.
Params:
map – Map to be searched.
elementFormat – The format to search.
Returns:
true if element name format found in the map, else false./**
     * Search if the given map has the given element format.
     *
     * @param map Map to be searched.
     * @param elementFormat The format to search.
     *
     * @return true if element name format found in the map, else false.
     */
    boolean foundGroupFormat(Map<String,?> map, String elementFormat) {
        if (map.containsKey(elementFormat)) {
            initMessages();
            messages.error("doclet.Same_element_name_used", elementFormat);
            return true;
        }
        return false;
    }

    
Group the modules according the grouping information provided on the
command line. Given a list of modules, search each module name in
regular expression map as well as module name map to get the
corresponding group name. Create another map with mapping of group name
to the module list, which will fall under the specified group. If any
module doesn't belong to any specified group on the command line, then
a new group named "Other Modules" will be created for it. If there are
no groups found, in other words if "-group" option is not at all used,
then all the modules will be grouped under group "Modules".
Params:
modules – Specified modules.
Returns:
map of group names and set of module elements./**
     * Group the modules according the grouping information provided on the
     * command line. Given a list of modules, search each module name in
     * regular expression map as well as module name map to get the
     * corresponding group name. Create another map with mapping of group name
     * to the module list, which will fall under the specified group. If any
     * module doesn't belong to any specified group on the command line, then
     * a new group named "Other Modules" will be created for it. If there are
     * no groups found, in other words if "-group" option is not at all used,
     * then all the modules will be grouped under group "Modules".
     *
     * @param modules Specified modules.
     * @return map of group names and set of module elements.
     */
    public Map<String, SortedSet<ModuleElement>> groupModules(Set<ModuleElement> modules) {
        Map<String, SortedSet<ModuleElement>> groupModuleMap = new HashMap<>();
        String defaultGroupName =
            (elementNameGroupMap.isEmpty() && regExpGroupMap.isEmpty())?
                configuration.getDocResources().getText("doclet.Modules") :
                configuration.getDocResources().getText("doclet.Other_Modules");
        // if the user has not used the default group name, add it
        if (!groupList.contains(defaultGroupName)) {
            groupList.add(defaultGroupName);
        }
        for (ModuleElement mdl : modules) {
            String moduleName = mdl.isUnnamed() ? null : mdl.getQualifiedName().toString();
            String groupName = mdl.isUnnamed() ? null : elementNameGroupMap.get(moduleName);
            // if this module is not explicitly assigned to a group,
            // try matching it to group specified by regular expression
            if (groupName == null) {
                groupName = regExpGroupName(moduleName);
            }
            // if it is in neither group map, put it in the default
            // group
            if (groupName == null) {
                groupName = defaultGroupName;
            }
            getModuleList(groupModuleMap, groupName).add(mdl);
        }
        return groupModuleMap;
    }

    
Group the packages according the grouping information provided on the
command line. Given a list of packages, search each package name in
regular expression map as well as package name map to get the
corresponding group name. Create another map with mapping of group name
to the package list, which will fall under the specified group. If any
package doesn't belong to any specified group on the command line, then
a new group named "Other Packages" will be created for it. If there are
no groups found, in other words if "-group" option is not at all used,
then all the packages will be grouped under group "Packages".
Params:
packages – Packages specified on the command line.
Returns:
map of group names and set of package elements/**
     * Group the packages according the grouping information provided on the
     * command line. Given a list of packages, search each package name in
     * regular expression map as well as package name map to get the
     * corresponding group name. Create another map with mapping of group name
     * to the package list, which will fall under the specified group. If any
     * package doesn't belong to any specified group on the command line, then
     * a new group named "Other Packages" will be created for it. If there are
     * no groups found, in other words if "-group" option is not at all used,
     * then all the packages will be grouped under group "Packages".
     *
     * @param packages Packages specified on the command line.
     * @return map of group names and set of package elements
     */
    public Map<String, SortedSet<PackageElement>> groupPackages(Set<PackageElement> packages) {
        Map<String, SortedSet<PackageElement>> groupPackageMap = new HashMap<>();
        String defaultGroupName =
            (elementNameGroupMap.isEmpty() && regExpGroupMap.isEmpty())?
                configuration.getDocResources().getText("doclet.Packages") :
                configuration.getDocResources().getText("doclet.Other_Packages");
        // if the user has not used the default group name, add it
        if (!groupList.contains(defaultGroupName)) {
            groupList.add(defaultGroupName);
        }
        for (PackageElement pkg : packages) {
            String pkgName = configuration.utils.getPackageName(pkg);
            String groupName = pkg.isUnnamed() ? null : elementNameGroupMap.get(pkgName);
            // if this package is not explicitly assigned to a group,
            // try matching it to group specified by regular expression
            if (groupName == null) {
                groupName = regExpGroupName(pkgName);
            }
            // if it is in neither group map, put it in the default
            // group
            if (groupName == null) {
                groupName = defaultGroupName;
            }
            getPkgList(groupPackageMap, groupName).add(pkg);
        }
        return groupPackageMap;
    }

    
Search for element name in the sorted regular expression
list, if found return the group name.  If not, return null.
Params:
elementName – Name of element to be found in the regular
expression list./**
     * Search for element name in the sorted regular expression
     * list, if found return the group name.  If not, return null.
     *
     * @param elementName Name of element to be found in the regular
     * expression list.
     */
    String regExpGroupName(String elementName) {
        for (String regexp : sortedRegExpList) {
            if (elementName.startsWith(regexp)) {
                return regExpGroupMap.get(regexp);
            }
        }
        return null;
    }

    
For the given group name, return the package list, on which it is mapped.
Create a new list, if not found.
Params:
map – Map to be searched for group name.
groupname – Group name to search./**
     * For the given group name, return the package list, on which it is mapped.
     * Create a new list, if not found.
     *
     * @param map Map to be searched for group name.
     * @param groupname Group name to search.
     */
    SortedSet<PackageElement> getPkgList(Map<String, SortedSet<PackageElement>> map,
            String groupname) {
        return map.computeIfAbsent(groupname, g -> new TreeSet<>(configuration.utils.comparators.makePackageComparator()));
    }

    
For the given group name, return the module list, on which it is mapped.
Create a new list, if not found.
Params:
map – Map to be searched for group name.
groupname – Group name to search./**
     * For the given group name, return the module list, on which it is mapped.
     * Create a new list, if not found.
     *
     * @param map Map to be searched for group name.
     * @param groupname Group name to search.
     */
    SortedSet<ModuleElement> getModuleList(Map<String, SortedSet<ModuleElement>> map,
            String groupname) {
        return map.computeIfAbsent(groupname, g -> new TreeSet<>(configuration.utils.comparators.makeModuleComparator()));
    }

    
Return the list of groups, in the same order as specified
on the command line.
/**
     * Return the list of groups, in the same order as specified
     * on the command line.
     */
    public List<String> getGroupList() {
        return groupList;
    }
}