/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Ant", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.tools.ant;

import java.io.*;

/**
 *  Writes build event to a PrintStream. Currently, it
 *  only writes which targets are being executed, and
 *  any messages that get logged.
 */
public class DefaultLogger implements BuildLogger {
    private static int LEFT_COLUMN_SIZE = 12;

    protected PrintStream out;
    protected PrintStream err;
    protected int msgOutputLevel = Project.MSG_ERR;
    private long startTime = System.currentTimeMillis();

    protected static String lSep = System.getProperty("line.separator");

    protected boolean emacsMode = false;

    /**
     * Set the msgOutputLevel this logger is to respond to.
     *
     * Only messages with a message level lower than or equal to the given level are 
     * output to the log.
     * <P>
     * Constants for the message levels are in Project.java. The order of
     * the levels, from least to most verbose, is MSG_ERR, MSG_WARN,
     * MSG_INFO, MSG_VERBOSE, MSG_DEBUG.
     *
     * The default message level for DefaultLogger is Project.MSG_ERR.
     *
     * @param level the logging level for the logger.
     */
    public void setMessageOutputLevel(int level) {
        this.msgOutputLevel = level;
    }

    
    /**
     * Set the output stream to which this logger is to send its output.
     *
     * @param output the output stream for the logger.
     */
    public void setOutputPrintStream(PrintStream output) {
        this.out = output;
    }

    /**
     * Set the output stream to which this logger is to send error messages.
     *
     * @param err the error stream for the logger.
     */
    public void setErrorPrintStream(PrintStream err) {
        this.err = err;
    }

    /**
     * Set this logger to produce emacs (and other editor) friendly output.
     *
     * @param emacsMode true if output is to be unadorned so that emacs and other
     * editors can parse files names, etc.
     */
    public void setEmacsMode(boolean emacsMode) {
        this.emacsMode = emacsMode;
    }


    public void buildStarted(BuildEvent event) {
        startTime = System.currentTimeMillis();
    }

    /**
     *  Prints whether the build succeeded or failed, and
     *  any errors the occured during the build.
     */
    public void buildFinished(BuildEvent event) {
        Throwable error = event.getException();

        if (error == null) {
            out.println(lSep + "BUILD SUCCESSFUL");
        }
        else {
            err.println(lSep + "BUILD FAILED" + lSep);

            if (Project.MSG_VERBOSE <= msgOutputLevel ||
                !(error instanceof BuildException)) {
                error.printStackTrace(err);
            }
            else {
                err.println(error.getMessage());
            }
        }

        out.println(lSep + "Total time: " + formatTime(System.currentTimeMillis() - startTime));
    }

    public void targetStarted(BuildEvent event) {
        if (Project.MSG_INFO <= msgOutputLevel) {
            out.println(lSep + event.getTarget().getName() + ":");
        }
    }

    public void targetFinished(BuildEvent event) {
    }

    public void taskStarted(BuildEvent event) {}
    public void taskFinished(BuildEvent event) {}

    public void messageLogged(BuildEvent event) {

        PrintStream logTo = event.getPriority() == Project.MSG_ERR ? err : out;

        // Filter out messages based on priority
        if (event.getPriority() <= msgOutputLevel) {

            // Print out the name of the task if we're in one
            if (event.getTask() != null) {
                String name = event.getTask().getTaskName();

                if (!emacsMode) {
                    String msg = "[" + name + "] ";
                    for (int i = 0; i < (LEFT_COLUMN_SIZE - msg.length()); i++) {
                        logTo.print(" ");
                    }
                    logTo.print(msg);
                }
            }

            // Print the message
            logTo.println(event.getMessage());
        }
    }

    protected static String formatTime(long millis) {
        long seconds = millis / 1000;
        long minutes = seconds / 60;


        if (minutes > 0) {
            return Long.toString(minutes) + " minute"
                + (minutes == 1 ? " " : "s ")
                + Long.toString(seconds%60) + " second"
                + (seconds%60 == 1 ? "" : "s");
        }
        else {
            return Long.toString(seconds) + " second"
                + (seconds%60 == 1 ? "" : "s");
        }

    }

}