/*

 * Copyright (c) 2010, 2013, 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 jdk.nashorn.internal.runtime;

import java.io.PrintWriter;

import java.util.logging.Level;

import java.util.logging.Logger;

import jdk.nashorn.internal.runtime.options.Options;

/**

 * Wrapper class for Logging system. This is how you are supposed to register a logger and use it

 */

    @SuppressWarnings("NonConstantLogger")

    private final Logger  logger;

    private final boolean isEnabled;

    private int indent;

    private static final int INDENT_SPACE = 4;

    /**

     * Constructor

     *

     * @param loggerName name of logger - this is the unique key with which it can be identified

     */

    public DebugLogger(final String loggerName) {

        this(loggerName, null);

    }

    /**

     * Constructor

     *

     * A logger can be paired with a property, e.g. {@code --log:codegen:info} is equivalent to {@code -Dnashorn.codegen.log}

     *

     * @param loggerName name of logger - this is the unique key with which it can be identified

     * @param property   system property activating the logger on {@code info} level

     */

    public DebugLogger(final String loggerName, final String property) {

        if (property != null && Options.getBooleanProperty(property)) {

            this.logger = Logging.getOrCreateLogger(loggerName, Level.INFO);

        } else {

            this.logger = Logging.getLogger(loggerName);

        }

        this.isEnabled = logger.getLevel() != Level.OFF;

    }

    /**

     * Get the output writer for the logger. Loggers always default to

     * stderr for output as they are used mainly to output debug info

     *

     * @return print writer for log output.

     */

    public PrintWriter getOutputStream() {

        return Context.getCurrentErr();

    }

    /**

     * Check if the logger is enabled

     * @return true if enabled

     */

    public boolean isEnabled() {

        return isEnabled;

    }

    /**

     * If you want to change the indent level of your logger, call indent with a new position.

     * Positions start at 0 and are increased by one for a new "tab"

     *

     * @param pos indent position

     */

    public void indent(final int pos) {

        if (isEnabled) {

           indent += pos * INDENT_SPACE;

        }

    }

    /**

     * Add an indent position

     */

    public void indent() {

        indent += INDENT_SPACE;

    }

    /**

     * Unindent a position

     */

    public void unindent() {

        indent -= INDENT_SPACE;

        if (indent < 0) {

            indent = 0;

        }

    }

    /**

     * Check if the logger is above of the level of detail given

     * @see java.util.logging.Level

     *

     * @param level logging level

     * @return true if level is above the given one

     */

    public boolean levelAbove(final Level level) {

        return logger.getLevel().intValue() > level.intValue();

    }

    /**

     * Shorthand for outputting a log string as log level {@link java.util.logging.Level#FINEST} on this logger

     * @param str the string to log

     */

    public void finest(final String str) {

        log(str, Level.FINEST);

    }

    /**

     * Shorthand for outputting a log string as log level

     * {@link java.util.logging.Level#FINER} on this logger

     * @param str the string to log

     */

    public void finer(final String str) {

        log(str, Level.FINER);

    }

    /**

     * Shorthand for outputting a log string as log level

     * {@link java.util.logging.Level#FINE} on this logger

     * @param str the string to log

     */

    public void fine(final String str) {

        log(str, Level.FINE);

    }

    /**

     * Shorthand for outputting a log string as log level

     * {@link java.util.logging.Level#CONFIG} on this logger

     * @param str the string to log

     */

    public void config(final String str) {

        log(str, Level.CONFIG);

    }

    /**

     * Shorthand for outputting a log string as log level

     * {@link java.util.logging.Level#INFO} on this logger

     * @param str the string to log

     */

    public void info(final String str) {

        log(str, Level.INFO);

    }

    /**

     * Shorthand for outputting a log string as log level

     * {@link java.util.logging.Level#WARNING} on this logger

     * @param str the string to log

     */

    public void warning(final String str) {

        log(str, Level.WARNING);

    }

    /**

     * Shorthand for outputting a log string as log level

     * {@link java.util.logging.Level#SEVERE} on this logger

     * @param str the string to log

     */

    public void severe(final String str) {

        log(str, Level.SEVERE);

    }

    /**

     * Output log line on this logger at a given level of verbosity

     * @see java.util.logging.Level

     *

     * @param str   string to log

     * @param level minimum log level required for logging to take place

     */

    public void log(final String str, final Level level) {

        if (isEnabled) {

            final StringBuilder sb = new StringBuilder();

            for (int i = 0 ; i < indent ; i++) {

                sb.append(' ');

            }

            sb.append(str);

            logger.log(level, sb.toString());

        }

    }

}