/*
 * Copyright (c) 2012, 2017, 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.doclint;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;

import javax.lang.model.element.Name;
import javax.tools.StandardLocation;

import com.sun.source.doctree.DocCommentTree;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.CompilationUnitTree;
import com.sun.source.tree.ModuleTree;
import com.sun.source.tree.PackageTree;
import com.sun.source.tree.MethodTree;
import com.sun.source.tree.Tree;
import com.sun.source.tree.VariableTree;
import com.sun.source.util.JavacTask;
import com.sun.source.util.Plugin;
import com.sun.source.util.TaskEvent;
import com.sun.source.util.TaskListener;
import com.sun.source.util.TreePath;
import com.sun.source.util.TreePathScanner;
import com.sun.tools.javac.api.JavacTaskImpl;
import com.sun.tools.javac.api.JavacTool;
import com.sun.tools.javac.file.JavacFileManager;
import com.sun.tools.javac.main.JavaCompiler;
import com.sun.tools.javac.util.Context;
import com.sun.tools.javac.util.DefinedBy;
import com.sun.tools.javac.util.DefinedBy.Api;

Multi-function entry point for the doc check utility.
This class can be invoked in the following ways:

From the command line
From javac, as a plugin
Directly, via a simple API

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.
/**
 * Multi-function entry point for the doc check utility.
 *
 * This class can be invoked in the following ways:
 * <ul>
 * <li>From the command line
 * <li>From javac, as a plugin
 * <li>Directly, via a simple API
 * </ul>
 *
 * <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></p>
 */
public class DocLint implements Plugin {

    public static final String XMSGS_OPTION = "-Xmsgs";
    public static final String XMSGS_CUSTOM_PREFIX = "-Xmsgs:";
    private static final String STATS = "-stats";
    public static final String XIMPLICIT_HEADERS = "-XimplicitHeaders:";
    public static final String XCUSTOM_TAGS_PREFIX = "-XcustomTags:";
    public static final String XHTML_VERSION_PREFIX = "-XhtmlVersion:";
    public static final String XCHECK_PACKAGE = "-XcheckPackage:";
    public static final String SEPARATOR = ",";

    // <editor-fold defaultstate="collapsed" desc="Command-line entry point">
    public static void main(String... args) {
        DocLint dl = new DocLint();
        try {
            dl.run(args);
        } catch (BadArgs e) {
            System.err.println(e.getMessage());
            System.exit(1);
        } catch (IOException e) {
            System.err.println(dl.localize("dc.main.ioerror", e.getLocalizedMessage()));
            System.exit(2);
        }
    }

    // </editor-fold>

    // <editor-fold defaultstate="collapsed" desc="Simple API">

    public class BadArgs extends Exception {
        private static final long serialVersionUID = 0;
        BadArgs(String code, Object... args) {
            super(localize(code, args));
            this.code = code;
            this.args = args;
        }

        final String code;
        final Object[] args;
    }

    
Simple API entry point.
Params:
args – Options and operands for doclint
Throws:
BadArgs – if an error is detected in any args
IOException – if there are problems with any of the file arguments/**
     * Simple API entry point.
     * @param args Options and operands for doclint
     * @throws BadArgs if an error is detected in any args
     * @throws IOException if there are problems with any of the file arguments
     */
    public void run(String... args) throws BadArgs, IOException {
        PrintWriter out = new PrintWriter(System.out);
        try {
            run(out, args);
        } finally {
            out.flush();
        }
    }

    public void run(PrintWriter out, String... args) throws BadArgs, IOException {
        env = new Env();
        processArgs(args);

        boolean noFiles = javacFiles.isEmpty();
        if (needHelp) {
            showHelp(out);
            if (noFiles)
                return;
        } else if (noFiles) {
            out.println(localize("dc.main.no.files.given"));
            return;
        }

        JavacTool tool = JavacTool.create();

        JavacFileManager fm = new JavacFileManager(new Context(), false, null);
        fm.setSymbolFileEnabled(false);
        if (javacBootClassPath != null) {
            fm.setLocation(StandardLocation.PLATFORM_CLASS_PATH, javacBootClassPath);
        }
        if (javacClassPath != null) {
            fm.setLocation(StandardLocation.CLASS_PATH, javacClassPath);
        }
        if (javacSourcePath != null) {
            fm.setLocation(StandardLocation.SOURCE_PATH, javacSourcePath);
        }

        JavacTask task = tool.getTask(out, fm, null, javacOpts, null,
                fm.getJavaFileObjectsFromFiles(javacFiles));
        Iterable<? extends CompilationUnitTree> units = task.parse();
        ((JavacTaskImpl) task).enter();

        env.init(task);
        checker = new Checker(env);

        DeclScanner ds = new DeclScanner(env) {
            @Override
            void visitDecl(Tree tree, Name name) {
                TreePath p = getCurrentPath();
                DocCommentTree dc = env.trees.getDocCommentTree(p);

                checker.scan(dc, p);
            }
        };

        ds.scan(units, null);

        reportStats(out);

        Context ctx = ((JavacTaskImpl) task).getContext();
        JavaCompiler c = JavaCompiler.instance(ctx);
        c.printCount("error", c.errorCount());
        c.printCount("warn", c.warningCount());
    }

    void processArgs(String... args) throws BadArgs {
        javacOpts = new ArrayList<>();
        javacFiles = new ArrayList<>();

        if (args.length == 0)
            needHelp = true;

        for (int i = 0; i < args.length; i++) {
            String arg = args[i];
            if (arg.matches("-Xmax(errs|warns)") && i + 1 < args.length) {
                if (args[++i].matches("[0-9]+")) {
                    javacOpts.add(arg);
                    javacOpts.add(args[i]);
                } else {
                    throw new BadArgs("dc.bad.value.for.option", arg, args[i]);
                }
            } else if ((arg.equals("-target") || arg.equals("-source")) && i + 1 < args.length) {
                javacOpts.add(arg);
                javacOpts.add(args[++i]);
            } else if (arg.equals(STATS)) {
                env.messages.setStatsEnabled(true);
            } else if (arg.equals("-bootclasspath") && i + 1 < args.length) {
                javacBootClassPath = splitPath(args[++i]);
            } else if (arg.equals("-classpath") && i + 1 < args.length) {
                javacClassPath = splitPath(args[++i]);
            } else if (arg.equals("-cp") && i + 1 < args.length) {
                javacClassPath = splitPath(args[++i]);
            } else if (arg.equals("-sourcepath") && i + 1 < args.length) {
                javacSourcePath = splitPath(args[++i]);
            } else if (arg.equals(XMSGS_OPTION)) {
                env.messages.setOptions(null);
            } else if (arg.startsWith(XMSGS_CUSTOM_PREFIX)) {
                env.messages.setOptions(arg.substring(arg.indexOf(":") + 1));
            } else if (arg.startsWith(XCUSTOM_TAGS_PREFIX)) {
                env.setCustomTags(arg.substring(arg.indexOf(":") + 1));
            } else if (arg.startsWith(XHTML_VERSION_PREFIX)) {
                String argsVersion = arg.substring(arg.indexOf(":") + 1);
                HtmlVersion htmlVersion = HtmlVersion.getHtmlVersion(argsVersion);
                if (htmlVersion != null) {
                    env.setHtmlVersion(htmlVersion);
                } else {
                    throw new BadArgs("dc.bad.value.for.option", arg, argsVersion);
                }
            } else if (arg.equals("-h") || arg.equals("-help") || arg.equals("--help")
                    || arg.equals("-?") || arg.equals("-usage")) {
                needHelp = true;
            } else if (arg.startsWith("-")) {
                throw new BadArgs("dc.bad.option", arg);
            } else {
                while (i < args.length)
                    javacFiles.add(new File(args[i++]));
            }
        }
    }

    void showHelp(PrintWriter out) {
        String msg = localize("dc.main.usage");
        for (String line: msg.split("\n"))
            out.println(line);
    }

    List<File> splitPath(String path) {
        List<File> files = new ArrayList<>();
        for (String f: path.split(File.pathSeparator)) {
            if (f.length() > 0)
                files.add(new File(f));
        }
        return files;
    }

    List<File> javacBootClassPath;
    List<File> javacClassPath;
    List<File> javacSourcePath;
    List<String> javacOpts;
    List<File> javacFiles;
    boolean needHelp = false;

    // </editor-fold>

    // <editor-fold defaultstate="collapsed" desc="javac Plugin">

    @Override @DefinedBy(Api.COMPILER_TREE)
    public String getName() {
        return "doclint";
    }

    @Override @DefinedBy(Api.COMPILER_TREE)
    public void init(JavacTask task, String... args) {
        init(task, args, true);
    }

    // </editor-fold>

    // <editor-fold defaultstate="collapsed" desc="Embedding API">

    public void init(JavacTask task, String[] args, boolean addTaskListener) {
        env = new Env();
        for (String arg : args) {
            if (arg.equals(XMSGS_OPTION)) {
                env.messages.setOptions(null);
            } else if (arg.startsWith(XMSGS_CUSTOM_PREFIX)) {
                env.messages.setOptions(arg.substring(arg.indexOf(":") + 1));
            } else if (arg.matches(XIMPLICIT_HEADERS + "[1-6]")) {
                char ch = arg.charAt(arg.length() - 1);
                env.setImplicitHeaders(Character.digit(ch, 10));
            } else if (arg.startsWith(XCUSTOM_TAGS_PREFIX)) {
                env.setCustomTags(arg.substring(arg.indexOf(":") + 1));
            } else if (arg.startsWith(XHTML_VERSION_PREFIX)) {
                String argsVersion = arg.substring(arg.indexOf(":") + 1);
                HtmlVersion htmlVersion = HtmlVersion.getHtmlVersion(argsVersion);
                if (htmlVersion != null) {
                    env.setHtmlVersion(htmlVersion);
                } else {
                    throw new IllegalArgumentException(argsVersion);
                }
            } else if (arg.startsWith(XCHECK_PACKAGE)) {
                env.setCheckPackages(arg.substring(arg.indexOf(":") + 1));
            } else
                throw new IllegalArgumentException(arg);
        }
        env.init(task);

        checker = new Checker(env);

        if (addTaskListener) {
            final DeclScanner ds = new DeclScanner(env) {
                @Override
                void visitDecl(Tree tree, Name name) {
                    TreePath p = getCurrentPath();
                    DocCommentTree dc = env.trees.getDocCommentTree(p);

                    checker.scan(dc, p);
                }
            };

            TaskListener tl = new TaskListener() {
                @Override @DefinedBy(Api.COMPILER_TREE)
                public void started(TaskEvent e) {
                    switch (e.getKind()) {
                        case ANALYZE:
                            CompilationUnitTree tree;
                            while ((tree = todo.poll()) != null)
                                ds.scan(tree, null);
                            break;
                    }
                }

                @Override @DefinedBy(Api.COMPILER_TREE)
                public void finished(TaskEvent e) {
                    switch (e.getKind()) {
                        case PARSE:
                            todo.add(e.getCompilationUnit());
                            break;
                    }
                }

                Queue<CompilationUnitTree> todo = new LinkedList<>();
            };

            task.addTaskListener(tl);
        }
    }

    public void scan(TreePath p) {
        DocCommentTree dc = env.trees.getDocCommentTree(p);
        checker.scan(dc, p);
    }

    public boolean shouldCheck(CompilationUnitTree unit) {
        return env.shouldCheck(unit);
    }

    public void reportStats(PrintWriter out) {
        env.messages.reportStats(out);
    }

    // </editor-fold>

    Env env;
    Checker checker;

    public static boolean isValidOption(String opt) {
        if (opt.equals(XMSGS_OPTION))
           return true;
        if (opt.startsWith(XMSGS_CUSTOM_PREFIX))
           return Messages.Options.isValidOptions(opt.substring(XMSGS_CUSTOM_PREFIX.length()));
        if (opt.startsWith(XCHECK_PACKAGE)) {
            return Env.validatePackages(opt.substring(opt.indexOf(":") + 1));
        }
        return false;
    }

    private String localize(String code, Object... args) {
        Messages m = (env != null) ? env.messages : new Messages(null);
        return m.localize(code, args);
    }

    // <editor-fold defaultstate="collapsed" desc="DeclScanner">

    static abstract class DeclScanner extends TreePathScanner<Void, Void> {
        final Env env;

        public DeclScanner(Env env) {
            this.env = env;
        }

        abstract void visitDecl(Tree tree, Name name);

        @Override @DefinedBy(Api.COMPILER_TREE)
        public Void visitPackage(PackageTree tree, Void ignore) {
            visitDecl(tree, null);
            return super.visitPackage(tree, ignore);
        }
        @Override @DefinedBy(Api.COMPILER_TREE)
        public Void visitClass(ClassTree tree, Void ignore) {
            visitDecl(tree, tree.getSimpleName());
            return super.visitClass(tree, ignore);
        }

        @Override @DefinedBy(Api.COMPILER_TREE)
        public Void visitMethod(MethodTree tree, Void ignore) {
            visitDecl(tree, tree.getName());
            //return super.visitMethod(tree, ignore);
            return null;
        }

        @Override @DefinedBy(Api.COMPILER_TREE)
        public Void visitModule(ModuleTree tree, Void ignore) {
            visitDecl(tree, null);
            return super.visitModule(tree, ignore);
        }

        @Override @DefinedBy(Api.COMPILER_TREE)
        public Void visitVariable(VariableTree tree, Void ignore) {
            visitDecl(tree, tree.getName());
            return super.visitVariable(tree, ignore);
        }

        @Override @DefinedBy(Api.COMPILER_TREE)
        public Void visitCompilationUnit(CompilationUnitTree node, Void p) {
            if (!env.shouldCheck(node)) {
                return null;
            }
            return super.visitCompilationUnit(node, p);
        }

    }

    // </editor-fold>

}