source: trunk/quest-ui-core/src/main/java/de/ugoe/cs/quest/commands/sequences/CMDgenerateReplayfile.java @ 733

package de.ugoe.cs.quest.commands.sequences;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.security.InvalidParameterException;
import java.util.Collection;
import java.util.List;
import java.util.logging.Level;

import de.ugoe.cs.quest.CommandHelpers;
import de.ugoe.cs.quest.IReplayDecorator;
import de.ugoe.cs.quest.SequenceInstanceOf;
import de.ugoe.cs.quest.eventcore.Event;
import de.ugoe.cs.quest.eventcore.IReplayable;
import de.ugoe.cs.util.StringTools;
import de.ugoe.cs.util.console.Command;
import de.ugoe.cs.util.console.Console;
import de.ugoe.cs.util.console.GlobalDataContainer;

/**
 * <p>
 * Command to create a replay file from stored sessions.
 * </p>
 * 
 * TODO: Add appropriate checks if Events are replayable
 * 
 * @author Steffen Herbold
 * @version 1.0
 */
public class CMDgenerateReplayfile implements Command {

        /*
         * (non-Javadoc)
         * 
         * @see de.ugoe.cs.util.console.Command#help()
         */
        @Override
        public String help() {
                return "generateReplayfile <filename> <sequences>";
        }

        /*
         * (non-Javadoc)
         * 
         * @see de.ugoe.cs.util.console.Command#run(java.util.List)
         */
        @SuppressWarnings("unchecked")
        @Override
        public void run(List<Object> parameters) {
                String filename;
                String sequencesName;
                try {
                        filename = (String) parameters.get(0);
                        sequencesName = (String) parameters.get(1);
                } catch (Exception e) {
                        throw new InvalidParameterException();
                }

                Collection<List<Event>> sequences = null;
                Object dataObject = GlobalDataContainer.getInstance().getData(
                                sequencesName);
                if (dataObject == null) {
                        CommandHelpers.objectNotFoundMessage(sequencesName);
                        return;
                }
                if (!SequenceInstanceOf.isCollectionOfSequences(dataObject)) {
                        CommandHelpers.objectNotType(sequencesName,
                                        "Collection<List<Event<?>>>");
                        return;
                }

                sequences = (Collection<List<Event>>) dataObject;
                createLogfileMultipleSessions(sequences, filename);
        }
        
            /**
             * <p>
             * {@link IReplayDecorator} to be used. If this field is {@code null}, no decorator is used.
             * Default: {@code null}
             * </p>
             */
            private IReplayDecorator decorator = null;

            /**
             * <p>
             * Id of the current session. The starting id is 1.
             * </p>
             */
            int sessionId = 1;

            /**
             * <p>
             * Creates a replay file that contains multiple event sequences.
             * </p>
             * 
             * @param sequences
             *            collection of event sequences from which the sessions are generated
             * @param filename
             *            name and path of the replay file
             */
            private void createLogfileMultipleSessions(Collection<List<Event>> sequences, String filename) {
                OutputStreamWriter writer = openReplayFile(filename);
                if (writer != null) {
                    try {
                        try {
                            decorator =
                                sequences.iterator().next().get(0).getReplayables().get(0).getDecorator();
                        }
                        catch (Exception e) {
                            // in the above line, many things can go wrong: emtpy sequences, null
                            // references, etc. However, all failures just indicate that no replay decorator
                            // should be used, hence, we ignore the exception
                        }
                        if (decorator != null) {
                            writer.write(decorator.getHeader());
                        }
                        for (List<Event> actions : sequences) {
                            writeSession(actions, writer);
                        }
                        if (decorator != null) {
                            writer.write(decorator.getFooter());
                        }
                        decorator = null;
                        writer.close();
                    }
                    catch (IOException e) {
                        Console.printerrln("Unable to write replay file " + filename);
                    }
                }
            }

            /**
             * <p>
             * Helper function that opens the replay file for writing.
             * </p>
             * 
             * @param filename
             *            name and path of the replay file
             * @return {@link OutputStreamWriter} that writes to the replay file
             */
            private OutputStreamWriter openReplayFile(String filename) {
                File file = new File(filename);
                boolean fileCreated;
                try {
                    fileCreated = file.createNewFile();
                    if (!fileCreated) {
                        Console.traceln(Level.INFO, "Created logfile " + filename);
                    }
                    else {
                        Console.traceln(Level.INFO, "Overwrote existing logfile " + filename);
                    }
                }
                catch (IOException e) {
                    Console.printerrln("Unable to create file " + filename);
                    Console.logException(e);
                }
                OutputStreamWriter writer = null;
                try {
                    writer = new OutputStreamWriter(new FileOutputStream(file), "UTF-16");
                }
                catch (IOException e) {
                    Console.printerrln("Unable to open file for writing (read-only file):" + filename);
                    Console.logException(e);
                }
                return writer;
            }

            /**
             * <p>
             * Helper function that adds an event sequence to the replay.
             * </p>
             * 
             * @param actions
             *            event sequences to be added
             * @param writer
             *            {@link OutputStreamWriter} to which the replay is added
             * @throws IOException
             *             thrown if there is a problem writing to writer
             */
            private void writeSession(List<Event> actions, OutputStreamWriter writer) throws IOException {
                if (decorator != null) {
                    writer.write(decorator.getSessionHeader(sessionId));
                }
                for (Event currentAction : actions) {

                    List<? extends IReplayable> replayables = currentAction.getReplayables();
                    for (IReplayable replayble : replayables) {
                        writer.write(replayble.getReplay() + StringTools.ENDLINE);
                        writer.flush();
                    }
                }
                if (decorator != null) {
                    writer.write(decorator.getSessionFooter(sessionId));
                }
                sessionId++;
            }
}