/*

 * 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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 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.

 */

package com.sun.tools.javac.main;

import java.io.*;

import java.util.HashSet;

import java.util.LinkedHashMap;

import java.util.Map;

import java.util.MissingResourceException;

import java.util.ResourceBundle;

import java.util.Set;

import java.util.logging.Handler;

import java.util.logging.Level;

import java.util.logging.Logger;

import javax.tools.JavaFileManager;

import javax.tools.JavaFileObject;

import javax.tools.DiagnosticListener;

import com.sun.tools.javac.file.JavacFileManager;

import com.sun.source.util.TaskEvent;

import com.sun.source.util.TaskListener;

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

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

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

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

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

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

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

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

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

import javax.annotation.processing.Processor;

import static javax.tools.StandardLocation.CLASS_OUTPUT;

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

// TEMP, until we have a more efficient way to save doc comment info

import com.sun.tools.javac.parser.DocCommentScanner;

import javax.lang.model.SourceVersion;

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

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

 *  construct a new compiler, and to run a new compiler on a set of source

 *  files.

 *

 *  <p><b>This is NOT part of any API supported by Sun Microsystems.  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 JavaCompiler implements ClassReader.SourceCompleter {

    /** The context key for the compiler. */

    protected static final Context.Key<JavaCompiler> compilerKey =

        new Context.Key<JavaCompiler>();

    /** Get the JavaCompiler instance for this context. */

    public static JavaCompiler instance(Context context) {

        JavaCompiler instance = context.get(compilerKey);

        if (instance == null)

            instance = new JavaCompiler(context);

        return instance;

    }

    /** The current version number as a string.

     */

    public static String version() {

        return version("release");  // mm.nn.oo[-milestone]

    }

    /** The current full version number as a string.

     */

    public static String fullVersion() {

        return version("full"); // mm.mm.oo[-milestone]-build

    }

    private static final String versionRBName = "com.sun.tools.javac.resources.version";

    private static ResourceBundle versionRB;

    private static String version(String key) {

        if (versionRB == null) {

            try {

                versionRB = ResourceBundle.getBundle(versionRBName);

            } catch (MissingResourceException e) {

                return Log.getLocalizedString("version.resource.missing", System.getProperty("java.version"));

            }

        }

        try {

            return versionRB.getString(key);

        }

        catch (MissingResourceException e) {

            return Log.getLocalizedString("version.unknown", System.getProperty("java.version"));

        }

    }

    private static enum CompilePolicy {

        /*

         * Just attribute the parse trees

         */

        ATTR_ONLY,

        /*

         * Just attribute and do flow analysis on the parse trees.

         * This should catch most user errors.

         */

        CHECK_ONLY,

        /*

         * Attribute everything, then do flow analysis for everything,

         * then desugar everything, and only then generate output.

         * Means nothing is generated if there are any errors in any classes.

         */

        SIMPLE,

        /*

         * After attributing everything and doing flow analysis,

         * group the work by compilation unit.

         * Then, process the work for each compilation unit together.

         * Means nothing is generated for a compilation unit if the are any errors

         * in the compilation unit  (or in any preceding compilation unit.)

         */

        BY_FILE,

        /*

         * Completely process each entry on the todo list in turn.

         * -- this is the same for 1.5.

         * Means output might be generated for some classes in a compilation unit

         * and not others.

         */

        BY_TODO;

        static CompilePolicy decode(String option) {

            if (option == null)

                return DEFAULT_COMPILE_POLICY;

            else if (option.equals("attr"))

                return ATTR_ONLY;

            else if (option.equals("check"))

                return CHECK_ONLY;

            else if (option.equals("simple"))

                return SIMPLE;

            else if (option.equals("byfile"))

                return BY_FILE;

            else if (option.equals("bytodo"))

                return BY_TODO;

            else

                return DEFAULT_COMPILE_POLICY;

        }

    }

    private static CompilePolicy DEFAULT_COMPILE_POLICY = CompilePolicy.BY_TODO;

    private static enum ImplicitSourcePolicy {

        /** Don't generate or process implicitly read source files. */

        NONE,

        /** Generate classes for implicitly read source files. */

        CLASS,

        /** Like CLASS, but generate warnings if annotation processing occurs */

        UNSET;

        static ImplicitSourcePolicy decode(String option) {

            if (option == null)

                return UNSET;

            else if (option.equals("none"))

                return NONE;

            else if (option.equals("class"))

                return CLASS;

            else

                return UNSET;

        }

    }

    /** The log to be used for error reporting.

     */

    public Log log;

    /** Factory for creating diagnostic objects

     */

    JCDiagnostic.Factory diagFactory;

    /** The tree factory module.

     */

    protected TreeMaker make;

    /** The class reader.

     */

    protected ClassReader reader;

    /** The class writer.

     */

    protected ClassWriter writer;

    /** The module for the symbol table entry phases.

     */

    protected Enter enter;

    /** The symbol table.

     */

    protected Symtab syms;

    /** The language version.

     */

    protected Source source;

    /** The module for code generation.

     */

    protected Gen gen;

    /** The name table.

     */

    protected Name.Table names;

    /** The attributor.

     */

    protected Attr attr;

    /** The attributor.

     */

    protected Check chk;

    /** The flow analyzer.

     */

    protected Flow flow;

    /** The type eraser.

     */

    TransTypes transTypes;

    /** The syntactic sugar desweetener.

     */

    Lower lower;

    /** The annotation annotator.

     */

    protected Annotate annotate;

    /** Force a completion failure on this name

     */

    protected final Name completionFailureName;

    /** Type utilities.

     */

    protected Types types;

    /** Access to file objects.

     */

    protected JavaFileManager fileManager;

    /** Factory for parsers.

     */

    protected Parser.Factory parserFactory;

    /** Optional listener for progress events

     */

    protected TaskListener taskListener;

    /**

     * Annotation processing may require and provide a new instance

     * of the compiler to be used for the analyze and generate phases.

     */

    protected JavaCompiler delegateCompiler;

    /**

     * Flag set if any annotation processing occurred.

     **/

    protected boolean annotationProcessingOccurred;

    /**

     * Flag set if any implicit source files read.

     **/

    protected boolean implicitSourceFilesRead;

    protected Context context;

    /** Construct a new compiler using a shared context.

     */

    public JavaCompiler(final Context context) {

        this.context = context;

        context.put(compilerKey, this);

        // if fileManager not already set, register the JavacFileManager to be used

        if (context.get(JavaFileManager.class) == null)

            JavacFileManager.preRegister(context);

        names = Name.Table.instance(context);

        log = Log.instance(context);

        diagFactory = JCDiagnostic.Factory.instance(context);

        reader = ClassReader.instance(context);

        make = TreeMaker.instance(context);

        writer = ClassWriter.instance(context);

        enter = Enter.instance(context);

        todo = Todo.instance(context);

        fileManager = context.get(JavaFileManager.class);

        parserFactory = Parser.Factory.instance(context);

        try {

            // catch completion problems with predefineds

            syms = Symtab.instance(context);

        } catch (CompletionFailure ex) {

            // inlined Check.completionError as it is not initialized yet

            log.error("cant.access", ex.sym, ex.getDetailValue());

            if (ex instanceof ClassReader.BadClassFile)

                throw new Abort();

        }

        source = Source.instance(context);

        attr = Attr.instance(context);

        chk = Check.instance(context);

        gen = Gen.instance(context);

        flow = Flow.instance(context);

        transTypes = TransTypes.instance(context);

        lower = Lower.instance(context);

        annotate = Annotate.instance(context);

        types = Types.instance(context);

        taskListener = context.get(TaskListener.class);

        reader.sourceCompleter = this;

        Options options = Options.instance(context);

        verbose       = options.get("-verbose")       != null;

        sourceOutput  = options.get("-printsource")   != null; // used to be -s

        stubOutput    = options.get("-stubs")         != null;

        relax         = options.get("-relax")         != null;

        printFlat     = options.get("-printflat")     != null;

        attrParseOnly = options.get("-attrparseonly") != null;

        encoding      = options.get("-encoding");

        lineDebugInfo = options.get("-g:")            == null ||

                        options.get("-g:lines")       != null;

        genEndPos     = options.get("-Xjcov")         != null ||

                        context.get(DiagnosticListener.class) != null;

        devVerbose    = options.get("dev") != null;

        processPcks   = options.get("process.packages") != null;

        verboseCompilePolicy = options.get("verboseCompilePolicy") != null;

        if (attrParseOnly)

            compilePolicy = CompilePolicy.ATTR_ONLY;

        else

            compilePolicy = CompilePolicy.decode(options.get("compilePolicy"));

        implicitSourcePolicy = ImplicitSourcePolicy.decode(options.get("-implicit"));

        completionFailureName =

            (options.get("failcomplete") != null)

            ? names.fromString(options.get("failcomplete"))

            : null;

    }

    /* Switches:

     */

    /** Verbose output.

     */

    public boolean verbose;

    /** Emit plain Java source files rather than class files.

     */

    public boolean sourceOutput;

    /** Emit stub source files rather than class files.

     */

    public boolean stubOutput;

    /** Generate attributed parse tree only.

     */

    public boolean attrParseOnly;

    /** Switch: relax some constraints for producing the jsr14 prototype.

     */

    boolean relax;

    /** Debug switch: Emit Java sources after inner class flattening.

     */

    public boolean printFlat;

    /** The encoding to be used for source input.

     */

    public String encoding;

    /** Generate code with the LineNumberTable attribute for debugging

     */

    public boolean lineDebugInfo;

    /** Switch: should we store the ending positions?

     */

    public boolean genEndPos;

    /** Switch: should we debug ignored exceptions

     */

    protected boolean devVerbose;

    /** Switch: should we (annotation) process packages as well

     */

    protected boolean processPcks;

    /** Switch: is annotation processing requested explitly via

     * CompilationTask.setProcessors?

     */

    protected boolean explicitAnnotationProcessingRequested = false;

    /**

     * The policy for the order in which to perform the compilation

     */

    protected CompilePolicy compilePolicy;

    /**

     * The policy for what to do with implicitly read source files

     */

    protected ImplicitSourcePolicy implicitSourcePolicy;

    /**

     * Report activity related to compilePolicy

     */

    public boolean verboseCompilePolicy;

    /** A queue of all as yet unattributed classes.

     */

    public Todo todo;

    private Set<Env<AttrContext>> deferredSugar = new HashSet<Env<AttrContext>>();

    /** The set of currently compiled inputfiles, needed to ensure

     *  we don't accidentally overwrite an input file when -s is set.

     *  initialized by `compile'.

     */

    protected Set<JavaFileObject> inputFiles = new HashSet<JavaFileObject>();

    /** The number of errors reported so far.

     */

    public int errorCount() {

        if (delegateCompiler != null && delegateCompiler != this)

            return delegateCompiler.errorCount();

        else

            return log.nerrors;

    }

    protected final <T> List<T> stopIfError(ListBuffer<T> listBuffer) {

        if (errorCount() == 0)

            return listBuffer.toList();

        else

            return List.nil();

    }

    protected final <T> List<T> stopIfError(List<T> list) {

        if (errorCount() == 0)

            return list;

        else

            return List.nil();

    }

    /** The number of warnings reported so far.

     */

    public int warningCount() {

        if (delegateCompiler != null && delegateCompiler != this)

            return delegateCompiler.warningCount();

        else

            return log.nwarnings;

    }

    /** Whether or not any parse errors have occurred.

     */

    public boolean parseErrors() {

        return parseErrors;

    }

    protected Scanner.Factory getScannerFactory() {

        return Scanner.Factory.instance(context);

    }

    /** Try to open input stream with given name.

     *  Report an error if this fails.

     *  @param filename   The file name of the input stream to be opened.

     */

    public CharSequence readSource(JavaFileObject filename) {

        try {

            inputFiles.add(filename);

            return filename.getCharContent(false);

        } catch (IOException e) {

            log.error("error.reading.file", filename, e.getLocalizedMessage());

            return null;

        }

    }

    /** Parse contents of input stream.

     *  @param filename     The name of the file from which input stream comes.

     *  @param input        The input stream to be parsed.

     */

    protected JCCompilationUnit parse(JavaFileObject filename, CharSequence content) {

        long msec = now();

        JCCompilationUnit tree = make.TopLevel(List.<JCTree.JCAnnotation>nil(),

                                      null, List.<JCTree>nil());

        if (content != null) {

            if (verbose) {

                printVerbose("parsing.started", filename);

            }

            if (taskListener != null) {

                TaskEvent e = new TaskEvent(TaskEvent.Kind.PARSE, filename);

                taskListener.started(e);

            }

            int initialErrorCount = log.nerrors;

            Scanner scanner = getScannerFactory().newScanner(content);