/*

 * Copyright (c) 2001, 2014, 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.javadoc;

import java.io.File;

import java.io.IOException;

import java.util.Collection;

import java.util.EnumSet;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Set;

import javax.tools.JavaFileManager.Location;

import javax.tools.JavaFileObject;

import javax.tools.StandardJavaFileManager;

import javax.tools.StandardLocation;

import com.sun.tools.javac.code.Symbol.CompletionFailure;

import com.sun.tools.javac.tree.JCTree;

import com.sun.tools.javac.tree.JCTree.JCClassDecl;

import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;

import com.sun.tools.javac.util.Abort;

import com.sun.tools.javac.util.Context;

import com.sun.tools.javac.util.List;

import com.sun.tools.javac.util.ListBuffer;

import com.sun.tools.javac.util.Position;

/**

 *  This class could be the main entry point for Javadoc when Javadoc is used as a

 *  component in a larger software system. It provides operations to

 *  construct a new javadoc processor, and to run it on a set of source

 *  files.

 *

 *  <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 Neal Gafter

 */

public class JavadocTool extends com.sun.tools.javac.main.JavaCompiler {

    DocEnv docenv;

    final Messager messager;

    final JavadocClassReader javadocReader;

    final JavadocEnter javadocEnter;

    /**

     * Construct a new JavaCompiler processor, using appropriately

     * extended phases of the underlying compiler.

     */

    protected JavadocTool(Context context) {

        super(context);

        messager = Messager.instance0(context);

        javadocReader = JavadocClassReader.instance0(context);

        javadocEnter = JavadocEnter.instance0(context);

    }

    /**

     * For javadoc, the parser needs to keep comments. Overrides method from JavaCompiler.

     */

    protected boolean keepComments() {

        return true;

    }

    /**

     *  Construct a new javadoc tool.

     */

    public static JavadocTool make0(Context context) {

        Messager messager = null;

        try {

            // force the use of Javadoc's class reader

            JavadocClassReader.preRegister(context);

            // force the use of Javadoc's own enter phase

            JavadocEnter.preRegister(context);

            // force the use of Javadoc's own member enter phase

            JavadocMemberEnter.preRegister(context);

            // force the use of Javadoc's own todo phase

            JavadocTodo.preRegister(context);

            // force the use of Messager as a Log

            messager = Messager.instance0(context);

            return new JavadocTool(context);

        } catch (CompletionFailure ex) {

            messager.error(Position.NOPOS, ex.getMessage());

            return null;

        }

    }

    public RootDocImpl getRootDocImpl(String doclocale,

                                      String encoding,

                                      ModifierFilter filter,

                                      List<String> javaNames,

                                      List<String[]> options,

                                      Iterable<? extends JavaFileObject> fileObjects,

                                      boolean breakiterator,

                                      List<String> subPackages,

                                      List<String> excludedPackages,

                                      boolean docClasses,

                                      boolean legacyDoclet,

                      boolean quiet) throws IOException {

        docenv = DocEnv.instance(context);

        docenv.showAccess = filter;

        docenv.quiet = quiet;

        docenv.breakiterator = breakiterator;

        docenv.setLocale(doclocale);

        docenv.setEncoding(encoding);

        docenv.docClasses = docClasses;

        docenv.legacyDoclet = legacyDoclet;

        javadocReader.sourceCompleter = docClasses ? null : thisCompleter;

        ListBuffer<String> names = new ListBuffer<>();

        ListBuffer<JCCompilationUnit> classTrees = new ListBuffer<>();

        ListBuffer<JCCompilationUnit> packTrees = new ListBuffer<>();

        try {

            StandardJavaFileManager fm = docenv.fileManager instanceof StandardJavaFileManager

                    ? (StandardJavaFileManager) docenv.fileManager : null;

            for (List<String> it = javaNames; it.nonEmpty(); it = it.tail) {

                String name = it.head;

                if (!docClasses && fm != null && name.endsWith(".java") && new File(name).exists()) {

                    JavaFileObject fo = fm.getJavaFileObjects(name).iterator().next();

                } else if (isValidPackageName(name)) {

                    names = names.append(name);

                } else if (name.endsWith(".java")) {

                    if (fm == null)

                        throw new IllegalArgumentException();

                    else

                        docenv.error(null, "main.file_not_found", name);

                } else {

                    docenv.error(null, "main.illegal_package_name", name);

                }

            }

            for (JavaFileObject fo: fileObjects) {

            }

            if (!docClasses) {

                // Recursively search given subpackages.  If any packages

                //are found, add them to the list.

                Map<String,List<JavaFileObject>> packageFiles =

                        searchSubPackages(subPackages, names, excludedPackages);

                // Parse the packages

                for (List<String> packs = names.toList(); packs.nonEmpty(); packs = packs.tail) {

                    // Parse sources ostensibly belonging to package.

                    String packageName = packs.head;

                    parsePackageClasses(packageName, packageFiles.get(packageName), packTrees, excludedPackages);

                }

                if (messager.nerrors() != 0) return null;

                // Enter symbols for all files

                docenv.notice("main.Building_tree");

                javadocEnter.main(classTrees.toList().appendList(packTrees.toList()));

            }

        } catch (Abort ex) {}

        if (messager.nerrors() != 0)

            return null;

        if (docClasses)

            return new RootDocImpl(docenv, javaNames, options);

        else

            return new RootDocImpl(docenv, listClasses(classTrees.toList()), names.toList(), options);

    }

    /** Is the given string a valid package name? */

    boolean isValidPackageName(String s) {

        int index;

        while ((index = s.indexOf('.')) != -1) {

            if (!isValidClassName(s.substring(0, index))) return false;

            s = s.substring(index+1);

        }

        return isValidClassName(s);

    }

    /**

     * search all directories in path for subdirectory name. Add all

     * .java files found in such a directory to args.

     */

    private void parsePackageClasses(String name,

            ListBuffer<JCCompilationUnit> trees,

            List<String> excludedPackages)

            throws IOException {

        if (excludedPackages.contains(name)) {

            return;

        }

        docenv.notice("main.Loading_source_files_for_package", name);

        if (files == null) {

            Location location = docenv.fileManager.hasLocation(StandardLocation.SOURCE_PATH)

                    ? StandardLocation.SOURCE_PATH : StandardLocation.CLASS_PATH;

            ListBuffer<JavaFileObject> lb = new ListBuffer<>();

            for (JavaFileObject fo: docenv.fileManager.list(

                    location, name, EnumSet.of(JavaFileObject.Kind.SOURCE), false)) {

                String binaryName = docenv.fileManager.inferBinaryName(location, fo);

                String simpleName = getSimpleName(binaryName);

                if (isValidClassName(simpleName)) {

                    lb.append(fo);

                }

            }

            files = lb.toList();

        }

        }

    }

    /**

     * Recursively search all directories in path for subdirectory name.

     * Add all packages found in such a directory to packages list.

     */

    private Map<String,List<JavaFileObject>> searchSubPackages(

            List<String> subPackages,

            ListBuffer<String> packages,

            List<String> excludedPackages)

            throws IOException {

        Map<String,List<JavaFileObject>> packageFiles = new HashMap<>();

        Map<String,Boolean> includedPackages = new HashMap<>();

        includedPackages.put("", true);

        for (String p: excludedPackages)

            includedPackages.put(p, false);

        StandardLocation path = docenv.fileManager.hasLocation(StandardLocation.SOURCE_PATH)

                ? StandardLocation.SOURCE_PATH : StandardLocation.CLASS_PATH;

        searchSubPackages(subPackages,

                includedPackages,

                packages, packageFiles,

                path,

                EnumSet.of(JavaFileObject.Kind.SOURCE));

        return packageFiles;

    }

    private void searchSubPackages(List<String> subPackages,

            Map<String,Boolean> includedPackages,

            ListBuffer<String> packages,

            Map<String, List<JavaFileObject>> packageFiles,

            StandardLocation location, Set<JavaFileObject.Kind> kinds)

            throws IOException {

        for (String subPackage: subPackages) {

            if (!isIncluded(subPackage, includedPackages))

                continue;

            for (JavaFileObject fo: docenv.fileManager.list(location, subPackage, kinds, true)) {

                String binaryName = docenv.fileManager.inferBinaryName(location, fo);

                String packageName = getPackageName(binaryName);

                String simpleName = getSimpleName(binaryName);

                if (isIncluded(packageName, includedPackages) && isValidClassName(simpleName)) {

                    List<JavaFileObject> list = packageFiles.get(packageName);

                    list = (list == null ? List.of(fo) : list.prepend(fo));

                    packageFiles.put(packageName, list);

                    if (!packages.contains(packageName))

                        packages.add(packageName);

                }

            }

        }

    }

    private String getPackageName(String name) {

        int lastDot = name.lastIndexOf(".");

        return (lastDot == -1 ? "" : name.substring(0, lastDot));

    }

    private String getSimpleName(String name) {

        int lastDot = name.lastIndexOf(".");

        return (lastDot == -1 ? name : name.substring(lastDot + 1));

    }

    private boolean isIncluded(String packageName, Map<String,Boolean> includedPackages) {

        Boolean b = includedPackages.get(packageName);

        if (b == null) {

            b = isIncluded(getPackageName(packageName), includedPackages);

            includedPackages.put(packageName, b);

        }

        return b;

    }

    /**

     * Recursively search all directories in path for subdirectory name.

     * Add all packages found in such a directory to packages list.

     */

    private void searchSubPackage(String packageName,

                                  ListBuffer<String> packages,

                                  List<String> excludedPackages,

                                  Collection<File> pathnames) {

        if (excludedPackages.contains(packageName))

            return;

        String packageFilename = packageName.replace('.', File.separatorChar);

        boolean addedPackage = false;

        for (File pathname : pathnames) {

            File f = new File(pathname, packageFilename);

            String filenames[] = f.list();

            // if filenames not null, then found directory

            if (filenames != null) {

                for (String filename : filenames) {

                    if (!addedPackage

                            && (isValidJavaSourceFile(filename) ||

                                isValidJavaClassFile(filename))

                            && !packages.contains(packageName)) {

                        packages.append(packageName);

                        addedPackage = true;

                    } else if (isValidClassName(filename) &&

                               (new File(f, filename)).isDirectory()) {

                        searchSubPackage(packageName + "." + filename,

                                         packages, excludedPackages, pathnames);

                    }

                }

            }

        }

    }

    /**

     * Return true if given file name is a valid class file name.

     * @param file the name of the file to check.

     * @return true if given file name is a valid class file name

     * and false otherwise.

     */

    private static boolean isValidJavaClassFile(String file) {

        if (!file.endsWith(".class")) return false;

        String clazzName = file.substring(0, file.length() - ".class".length());

        return isValidClassName(clazzName);

    }

    /**

     * Return true if given file name is a valid Java source file name.

     * @param file the name of the file to check.

     * @return true if given file name is a valid Java source file name

     * and false otherwise.

     */

    private static boolean isValidJavaSourceFile(String file) {

        if (!file.endsWith(".java")) return false;

        String clazzName = file.substring(0, file.length() - ".java".length());

        return isValidClassName(clazzName);

    }

    /** Are surrogates supported?

     */

    final static boolean surrogatesSupported = surrogatesSupported();

    private static boolean surrogatesSupported() {

        try {

            boolean b = Character.isHighSurrogate('a');

            return true;

        } catch (NoSuchMethodError ex) {

            return false;

        }

    }

    /**

     * Return true if given file name is a valid class name

     * (including "package-info").

     * @param s the name of the class to check.

     * @return true if given class name is a valid class name

     * and false otherwise.

     */

    public static boolean isValidClassName(String s) {

        if (s.length() < 1) return false;

        if (s.equals("package-info")) return true;

        if (surrogatesSupported) {

            int cp = s.codePointAt(0);

            if (!Character.isJavaIdentifierStart(cp))

                return false;

            for (int j=Character.charCount(cp); j<s.length(); j+=Character.charCount(cp)) {

                cp = s.codePointAt(j);

                if (!Character.isJavaIdentifierPart(cp))

                    return false;

            }

        } else {

            if (!Character.isJavaIdentifierStart(s.charAt(0)))

                return false;

            for (int j=1; j<s.length(); j++)

                if (!Character.isJavaIdentifierPart(s.charAt(j)))

                    return false;

        }

        return true;

    }

    /**

     * From a list of top level trees, return the list of contained class definitions

     */

    List<JCClassDecl> listClasses(List<JCCompilationUnit> trees) {

        ListBuffer<JCClassDecl> result = new ListBuffer<>();

        for (JCCompilationUnit t : trees) {

            for (JCTree def : t.defs) {

                if (def.hasTag(JCTree.Tag.CLASSDEF))

                    result.append((JCClassDecl)def);

            }

        }

        return result.toList();

    }

}