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 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */


package org.graalvm.compiler.debug;

import java.io.PrintStream;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;

import org.graalvm.compiler.serviceprovider.GraalServices;

A collection of static methods for printing debug and informational output to a global LogStream. The output can be (temporarily) suppressed per thread through use of a filter. /**
 * A collection of static methods for printing debug and informational output to a global
 * {@link LogStream}. The output can be (temporarily) suppressed per thread through use of a
 * {@linkplain Filter filter}.
 */
public class TTY {

    
Support for thread-local suppression of TTY. /**
     * Support for thread-local suppression of {@link TTY}.
     */
    public static class Filter implements AutoCloseable {

        private LogStream previous;
        private final Thread thread = Thread.currentThread();

        
Creates an object that will suppress TTY for the current thread if the given filter does not match the given object. To revert the suppression state to how it was before this call, the remove() method must be called on the suppression object. 
Params:
filter – the pattern for matching. If null, then the match is successful. If it starts with "~", then a regular expression match is performed where the regular expression is specified by filter without the "~" prefix. Otherwise, a simple substring match is performed where filter is the substring used.
object – an object whose string value is matched against filter/**
         * Creates an object that will suppress {@link TTY} for the current thread if the given
         * filter does not match the given object. To revert the suppression state to how it was
         * before this call, the {@link #remove()} method must be called on the suppression object.
         *
         * @param filter the pattern for matching. If {@code null}, then the match is successful. If
         *            it starts with "~", then a regular expression
         *            {@linkplain Pattern#matches(String, CharSequence) match} is performed where
         *            the regular expression is specified by {@code filter} without the "~" prefix.
         *            Otherwise, a simple {@linkplain String#contains(CharSequence) substring} match
         *            is performed where {@code filter} is the substring used.
         * @param object an object whose {@linkplain Object#toString() string} value is matched
         *            against {@code filter}
         */
        public Filter(String filter, Object object) {
            boolean suppressed = false;
            if (filter != null) {
                String input = object.toString();
                if (filter.startsWith("~")) {
                    suppressed = !Pattern.matches(filter.substring(1), input);
                } else {
                    suppressed = !input.contains(filter);
                }
                if (suppressed) {
                    previous = out();
                    log.set(LogStream.SINK);
                }
            }
        }

        
Creates an object that will suppress TTY for the current thread. To revert the suppression state to how it was before this call, the remove() method must be called on this filter object. /**
         * Creates an object that will suppress {@link TTY} for the current thread. To revert the
         * suppression state to how it was before this call, the {@link #remove()} method must be
         * called on this filter object.
         */
        public Filter() {
            previous = out();
            log.set(LogStream.SINK);
        }

        
Creates an object that will overwrite TTY for the current thread with a custom log stream. To revert the overwritten state to how it was before this call, the remove() method must be called on this filter object. /**
         * Creates an object that will overwrite {@link TTY} for the current thread with a custom
         * log stream. To revert the overwritten state to how it was before this call, the
         * {@link #remove()} method must be called on this filter object.
         */
        public Filter(LogStream newStream) {
            previous = out();
            log.set(newStream);
        }

        
Reverts the suppression state of TTY to how it was before this object was constructed. /**
         * Reverts the suppression state of {@link TTY} to how it was before this object was
         * constructed.
         */
        public void remove() {
            assert thread == Thread.currentThread();
            if (previous != null) {
                log.set(previous);
            }
        }

        @Override
        public void close() {
            remove();
        }
    }

    
The PrintStream to which all non-suppressed output from TTY is written. /**
     * The {@link PrintStream} to which all non-suppressed output from {@link TTY} is written.
     */
    public static final PrintStream out;
    static {
        TTYStreamProvider p = GraalServices.loadSingle(TTYStreamProvider.class, false);
        out = p == null ? System.out : p.getStream();
    }

    private static final ThreadLocal<LogStream> log = new ThreadLocal<LogStream>() {

        @Override
        protected LogStream initialValue() {
            return new LogStream(out);
        }
    };

    public static boolean isSuppressed() {
        return log.get() == LogStream.SINK;
    }

    
Gets the thread-local log stream to which the static methods of this class send their output. This will either be a global log stream or the global sink depending on whether any suppression filters are in effect for the current thread. /**
     * Gets the thread-local log stream to which the static methods of this class send their output.
     * This will either be a global log stream or the global {@linkplain LogStream#SINK sink}
     * depending on whether any suppression {@linkplain Filter filters} are in effect for the
     * current thread.
     */
    public static LogStream out() {
        return log.get();
    }

    
See Also:
print.print(String)/**
     * @see LogStream#print(String)
     */
    public static void print(String s) {
        out().print(s);
    }

    
See Also:
print.print(int)/**
     * @see LogStream#print(int)
     */
    public static void print(int i) {
        out().print(i);
    }

    
See Also:
print.print(long)/**
     * @see LogStream#print(long)
     */
    public static void print(long i) {
        out().print(i);
    }

    
See Also:
print.print(char)/**
     * @see LogStream#print(char)
     */
    public static void print(char c) {
        out().print(c);
    }

    
See Also:
print.print(boolean)/**
     * @see LogStream#print(boolean)
     */
    public static void print(boolean b) {
        out().print(b);
    }

    
See Also:
print.print(double)/**
     * @see LogStream#print(double)
     */
    public static void print(double d) {
        out().print(d);
    }

    
See Also:
print.print(float)/**
     * @see LogStream#print(float)
     */
    public static void print(float f) {
        out().print(f);
    }

    
See Also:
println.println(String)/**
     * @see LogStream#println(String)
     */
    public static void println(String s) {
        out().println(s);
    }

    
See Also:
println.println()/**
     * @see LogStream#println()
     */
    public static void println() {
        out().println();
    }

    
See Also:
println.println(int)/**
     * @see LogStream#println(int)
     */
    public static void println(int i) {
        out().println(i);
    }

    
See Also:
println.println(long)/**
     * @see LogStream#println(long)
     */
    public static void println(long l) {
        out().println(l);
    }

    
See Also:
println.println(char)/**
     * @see LogStream#println(char)
     */
    public static void println(char c) {
        out().println(c);
    }

    
See Also:
println.println(boolean)/**
     * @see LogStream#println(boolean)
     */
    public static void println(boolean b) {
        out().println(b);
    }

    
See Also:
println.println(double)/**
     * @see LogStream#println(double)
     */
    public static void println(double d) {
        out().println(d);
    }

    
See Also:
println.println(float)/**
     * @see LogStream#println(float)
     */
    public static void println(float f) {
        out().println(f);
    }

    public static void printf(String format, Object... args) {
        out().printf(format, args);
    }

    public static void println(String format, Object... args) {
        out().printf(format + "%n", args);
    }

    public static void fillTo(int i) {
        out().fillTo(i, ' ');
    }

    public static void printFields(Class<?> javaClass) {
        final String className = javaClass.getSimpleName();
        TTY.println(className + " {");
        for (final Field field : javaClass.getFields()) {
            printField(field, false);
        }
        TTY.println("}");
    }

    public static void printField(final Field field, boolean tabbed) {
        final String fieldName = String.format("%35s", field.getName());
        try {
            String prefix = tabbed ? "" : "    " + fieldName + " = ";
            String postfix = tabbed ? "\t" : "\n";
            if (field.getType() == int.class) {
                TTY.print(prefix + field.getInt(null) + postfix);
            } else if (field.getType() == boolean.class) {
                TTY.print(prefix + field.getBoolean(null) + postfix);
            } else if (field.getType() == float.class) {
                TTY.print(prefix + field.getFloat(null) + postfix);
            } else if (field.getType() == String.class) {
                TTY.print(prefix + field.get(null) + postfix);
            } else if (field.getType() == Map.class) {
                Map<?, ?> m = (Map<?, ?>) field.get(null);
                TTY.print(prefix + printMap(m) + postfix);
            } else {
                TTY.print(prefix + field.get(null) + postfix);
            }
        } catch (IllegalAccessException e) {
            // do nothing.
        }
    }

    private static String printMap(Map<?, ?> m) {
        StringBuilder sb = new StringBuilder();

        List<String> keys = new ArrayList<>();
        for (Object key : m.keySet()) {
            keys.add((String) key);
        }
        Collections.sort(keys);

        for (String key : keys) {
            sb.append(key);
            sb.append("\t");
            sb.append(m.get(key));
            sb.append("\n");
        }

        return sb.toString();
    }

    public static void flush() {
        out().flush();
    }
}