/*

 * Copyright 2010 Sun Microsystems, Inc.  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.

 *

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

/**

 * Utility and test program to check javac's internal TreeScanner class.

 * The program can be run standalone, or as a jtreg test.  For info on

 * command line args, run program with no args.

 *

 * <p>

 * jtreg: Note that by using the -r switch in the test description below, this test

 * will process all java files in the langtools/test directory, thus implicitly

 * covering any new language features that may be tested in this test suite.

 */

/*

 * @test

 * @bug 6923080

 * @summary TreeScanner.visitNewClass should scan tree.typeargs

 * @run main TreeScannerTest -q -r .

 */

import java.io.*;

import java.lang.reflect.*;

import java.util.*;

import javax.tools.*;

import com.sun.source.tree.CompilationUnitTree;

import com.sun.source.util.JavacTask;

import com.sun.tools.javac.api.JavacTool;

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

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

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

public class TreeScannerTest {

    /**

     * Main entry point.

     * If test.src is set, program runs in jtreg mode, and will throw an Error

     * if any errors arise, otherwise System.exit will be used. In jtreg mode,

     * the default base directory for file args is the value of ${test.src}.

     * In jtreg mode, the -r option can be given to change the default base

     * directory to the root test directory.

     */

    public static void main(String... args) {

        String testSrc = System.getProperty("test.src");

        File baseDir = (testSrc == null) ? null : new File(testSrc);

        boolean ok = new TreeScannerTest().run(baseDir, args);

        if (!ok) {

            if (testSrc != null)  // jtreg mode

                throw new Error("failed");

            else

                System.exit(1);

        }

    }

    /**

     * Run the program. A base directory can be provided for file arguments.

     * In jtreg mode, the -r option can be given to change the default base

     * directory to the test root directory. For other options, see usage().

     * @param baseDir base directory for any file arguments.

     * @param args command line args

     * @return true if successful or in gui mode

     */

    boolean run(File baseDir, String... args) {

        if (args.length == 0) {

            usage(System.out);

            return true;

        }

        ArrayList<File> files = new ArrayList<File>();

        for (int i = 0; i < args.length; i++) {

            String arg = args[i];

            if (arg.equals("-q"))

                quiet = true;

            else if (arg.equals("-v"))

                verbose = true;

            else if (arg.equals("-r")) {

                File d = baseDir;

                while (!new File(d, "TEST.ROOT").exists()) {

                    d = d.getParentFile();

                    if (d == null)

                        throw new Error("cannot find TEST.ROOT");

                }

                baseDir = d;

            }

            else if (arg.startsWith("-"))

                throw new Error("unknown option: " + arg);

            else {

                while (i < args.length)

                    files.add(new File(baseDir, args[i++]));

            }

        }

        for (File file: files) {

            if (file.exists())

                test(file);

            else

                error("File not found: " + file);

        }

        if (fileCount != 1)

            System.err.println(fileCount + " files read");

        if (errors > 0)

            System.err.println(errors + " errors");

        return (errors == 0);

    }

    /**

     * Print command line help.

     * @param out output stream

     */

    void usage(PrintStream out) {

        out.println("Usage:");

        out.println("  java TreeScannerTest options... files...");

        out.println("");

        out.println("where options include:");

        out.println("-q        Quiet: don't report on inapplicable files");

        out.println("-v        Verbose: report on files as they are being read");

        out.println("");

        out.println("files may be directories or files");

        out.println("directories will be scanned recursively");

        out.println("non java files, or java files which cannot be parsed, will be ignored");

        out.println("");

    }

    /**

     * Test a file. If the file is a directory, it will be recursively scanned

     * for java files.

     * @param file the file or directory to test

     */

    void test(File file) {

        if (file.isDirectory()) {

            for (File f: file.listFiles()) {

                test(f);

            }

            return;

        }

        if (file.isFile() && file.getName().endsWith(".java")) {

            try {

                if (verbose)

                    System.err.println(file);

                fileCount++;

                ScanTester t = new ScanTester();

                t.test(read(file));

            } catch (ParseException e) {

                if (!quiet) {

                    error("Error parsing " + file + "\n" + e.getMessage());

                }

            } catch (IOException e) {

                error("Error reading " + file + ": " + e);

            }

            return;

        }

        if (!quiet)

            error("File " + file + " ignored");

    }

    /**

     * Read a file.

     * @param file the file to be read

     * @return the tree for the content of the file

     * @throws IOException if any IO errors occur

     * @throws TreePosTest.ParseException if any errors occur while parsing the file

     */

    JCCompilationUnit read(File file) throws IOException, ParseException {

        StringWriter sw = new StringWriter();

        PrintWriter pw = new PrintWriter(sw);

        Reporter r = new Reporter(pw);

        JavacTool tool = JavacTool.create();

        StandardJavaFileManager fm = tool.getStandardFileManager(r, null, null);

        Iterable<? extends JavaFileObject> files = fm.getJavaFileObjects(file);

        JavacTask task = tool.getTask(pw, fm, r, Collections.<String>emptyList(), null, files);

        Iterable<? extends CompilationUnitTree> trees = task.parse();

        pw.flush();

        if (r.errors > 0)

            throw new ParseException(sw.toString());

        Iterator<? extends CompilationUnitTree> iter = trees.iterator();

        if (!iter.hasNext())

            throw new Error("no trees found");

        JCCompilationUnit t = (JCCompilationUnit) iter.next();

        if (iter.hasNext())

            throw new Error("too many trees found");

        return t;

    }

    /**

     * Report an error. When the program is complete, the program will either

     * exit or throw an Error if any errors have been reported.

     * @param msg the error message

     */

    void error(String msg) {

        System.err.println(msg);

        errors++;

    }

    /**

     *  Report an error for a specific tree node.

     *  @param file the source file for the tree

     *  @param t    the tree node

     *  @param label an indication of the error

     */

    void error(JavaFileObject file, JCTree t, String msg) {

        error(file.getName() + ":" + getLine(file, t) + ": " + msg + " " + trim(t, 64));

    }

    /**

     * Get a trimmed string for a tree node, with normalized white space and limited length.

     */

    String trim(JCTree t, int len) {

        String s = t.toString().replaceAll("[\r\n]+", " ").replaceAll(" +", " ");

        return (s.length() < len) ? s : s.substring(0, len);

    }

    /** Number of files that have been analyzed. */

    int fileCount;

    /** Number of errors reported. */

    int errors;

    /** Flag: don't report irrelevant files. */

    boolean quiet;

    /** Flag: report files as they are processed. */

    boolean verbose;

    /**

     * Main class for testing operation of tree scanner.

     * The set of nodes found by the scanner are compared

     * against the set of nodes found by reflection.

     */

    private class ScanTester extends TreeScanner {

        /** Main entry method for the class. */

        void test(JCCompilationUnit tree) {

            sourcefile = tree.sourcefile;

            found = new HashSet<JCTree>();

            scan(tree);

            expect = new HashSet<JCTree>();

            reflectiveScan(tree);

            if (found.equals(expect))

                return;

            error("Differences found for " + tree.sourcefile.getName());

            if (found.size() != expect.size())

                error("Size mismatch; found: " + found.size() + ", expected: " + expect.size());

            Set<JCTree> missing = new HashSet<JCTree>();

            missing.addAll(expect);

            missing.removeAll(found);

            for (JCTree t: missing)

                error(tree.sourcefile, t, "missing");

            Set<JCTree> excess = new HashSet<JCTree>();

            excess.addAll(found);

            excess.removeAll(expect);

            for (JCTree t: excess)

                error(tree.sourcefile, t, "unexpected");

        }

        /** Record all tree nodes found by scanner. */

        @Override

        public void scan(JCTree tree) {

            if (tree == null)

                return;

            System.err.println("FOUND: " + tree.getTag() + " " + trim(tree, 64));

            found.add(tree);

            super.scan(tree);

        }

        /** record all tree nodes found by reflection. */

        public void reflectiveScan(Object o) {

            if (o == null)

                return;

            if (o instanceof JCTree) {

                JCTree tree = (JCTree) o;

                System.err.println("EXPECT: " + tree.getTag() + " " + trim(tree, 64));

                expect.add(tree);

                for (Field f: getFields(tree)) {

                    try {

                        //System.err.println("FIELD: " + f.getName());

                        reflectiveScan(f.get(tree));

                    } catch (IllegalAccessException e) {

                        error(e.toString());

                    }

                }

            } else if (o instanceof List) {

                List<?> list = (List<?>) o;

                for (Object item: list)

                    reflectiveScan(item);

            } else

                error("unexpected item: " + o);

        }

        JavaFileObject sourcefile;

        Set<JCTree> found;

        Set<JCTree> expect;

    }

    /**

     * Thrown when errors are found parsing a java file.

     */

    private static class ParseException extends Exception {

        ParseException(String msg) {

            super(msg);

        }

    }

    /**

     * DiagnosticListener to report diagnostics and count any errors that occur.

     */

    private static class Reporter implements DiagnosticListener<JavaFileObject> {

        Reporter(PrintWriter out) {

            this.out = out;

        }

        public void report(Diagnostic<? extends JavaFileObject> diagnostic) {

            out.println(diagnostic);

            switch (diagnostic.getKind()) {

                case ERROR:

                    errors++;

            }

        }

        int errors;

        PrintWriter out;

    }

    /**

     * Get the set of fields for a tree node that may contain child tree nodes.

     * These are the fields that are subtypes of JCTree or List.

     * The results are cached, based on the tree's tag.

     */

    Set<Field> getFields(JCTree tree) {

        Set<Field> fields = map.get(tree.getTag());

        if (fields == null) {

            fields = new HashSet<Field>();

            for (Field f: tree.getClass().getFields()) {

                Class<?> fc = f.getType();

                if (JCTree.class.isAssignableFrom(fc) || List.class.isAssignableFrom(fc))

                    fields.add(f);

            }

            map.put(tree.getTag(), fields);

        }

        return fields;

    }

    // where

    Map<Integer, Set<Field>> map = new HashMap<Integer,Set<Field>>();

    /** Get the line number for the primary position for a tree.

     * The code is intended to be simple, although not necessarily efficient.

     * However, note that a file manager such as JavacFileManager is likely

     * to cache the results of file.getCharContent, avoiding the need to read

     * the bits from disk each time this method is called.

     */

    int getLine(JavaFileObject file, JCTree tree) {

        try {

            CharSequence cs = file.getCharContent(true);

            int line = 1;

            for (int i = 0; i < tree.pos; i++) {

                if (cs.charAt(i) == '\n') // jtreg tests always use Unix line endings

                    line++;

            }

            return line;

        } catch (IOException e) {

            return -1;

        }

    }

}