MusicTheoryHandler

/*
 * Copyright the original author or authors.
 * 
 * Licensed under the MOZILLA PUBLIC LICENSE, Version 1.1 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.mozilla.org/MPL/MPL-1.1.html
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import org.as2lib.util.Stringifier;
import org.as2lib.env.log.LogHandler;
import org.as2lib.env.log.LogMessage;
import org.as2lib.env.log.handler.AbstractLogHandler;

/**
 * {@code MusicTheoryHandler} writes messages to the SWF Console from Ricci Adams'
 * Musictheory.
 * 
 * @author Simon Wacker
 * @see org.as2lib.env.log.logger.MusicTheoryLogger
 * @see <a href="http://source.musictheory.net/swfconsole">SWF Console</a>
 */
class org.as2lib.env.log.handler.MusicTheoryHandler extends AbstractLogHandler implements LogHandler {
    
    /** Holds a music theory handler instance. */
    private static var musicTheoryHandler:MusicTheoryHandler;
    
    /**
     * Returns an instance of this class.
     *
     * <p>This method always returns the same instance.
     * 
     * <p>The {@code messageStringifier} argument is only recognized on first
     * invocation of this method.
     * 
     * @param messageStringifier (optional) the log message stringifier to be used by
     * the returned handler
     * @return a music theory handler
     */
    public static function getInstance(messageStringifier):MusicTheoryHandler {
        if (!musicTheoryHandler) musicTheoryHandler = new MusicTheoryHandler(messageStringifier);
        return musicTheoryHandler;
    }
    
    /**    
     * Constructs a new {@code MusicTheoryHandler} instance.
     * 
     * <p>You can use one and the same instance for multiple loggers. So think about
     * using the handler returned by the static {@link #getInstance} method. Using
     * this instance prevents the instantiation of unnecessary music theory handlers
     * and saves storage.
     * 
     * @param messageStringifier (optional) the log message stringifier to use
     */
    public function MusicTheoryHandler(messageStringifier:Stringifier) {
        super (messageStringifier);
    }
    
    /**
     * Writes the passed-in {@code message} to the Musictheory SWF Console.
     * 
     * <p>The string representation of the {@code message} to log is obtained via
     * the {@code convertMessage} method.
     *
     * @param message the log message to write
     */
    public function write(message:LogMessage):Void {
        getURL("javascript:showText('" + convertMessage(message) + "')");
    }
    
}