source: trunk/src/org/expeditee/io/ExpWriter.java@ 289

package org.expeditee.io;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.lang.reflect.Method;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import org.expeditee.agents.DefaultAgent;
import org.expeditee.gui.Frame;
import org.expeditee.items.Constraint;
import org.expeditee.items.Item;
import org.expeditee.items.Line;
import org.expeditee.items.widgets.WidgetEdge;
import org.expeditee.stats.SessionStats;

/**
 * Writes a Frame out to a Expeditee format file.
 * 
 * @author jdm18
 * 
 */
public class ExpWriter extends DefaultFrameWriter {

        private ProxyWriter _writer = null;

        private StringBuilder _stringWriter = null;

        private static final char TERMINATOR = 'Z';

        public ExpWriter() {
                super();
        }

        public void initialise(Frame start) throws IOException {
                String name = start.getFramesetName().toLowerCase();

                if (_filename == null)
                        _filename = start.path + name + File.separator
                                        + start.getNumber() + ExpReader.EXTENTION;

                _stringWriter = new StringBuilder();
                if (_filename.equalsIgnoreCase(DefaultAgent.CLIPBOARD)) {
                        _writer = new ProxyWriter(true);
                        _filename = DefaultAgent.CLIPBOARD;
                } else
                        _writer = new ProxyWriter(new FileWriter(_filename));
                
                try {
                        _FrameTags.remove("A");
                        _ItemTags.put("S", Item.class.getMethod("getTypeAndID", new Class[] {}));
                } catch (Exception e) {

                }
        }

        /**
         * Writes the given Frame (and all items it contains) to a Expeditee file. Note:
         * File path and location must be set before calling this or it will do
         * nothing.
         * 
         * @param frame
         *            The Frame to write out to the file.
         * @throws IOException
         *             Any exceptions occured by the BufferedWriter.
         */
        public void outputFrame(Frame frame) throws IOException {
                if (_writer == null)
                        return;

                writeHeader(frame);


                // write each item in the frame
                for (Item i : frame.getItemsToSave()) {
                        assert(!(i instanceof Line));
                        writeItem(i);
                }

                // write any lines or constraints
                writeTerminator();
                writeLineData();
                writeTerminator();
                writeConstraintData();
                writeTerminator();
                writeLine(SessionStats.getFrameEventList(frame));
                
                return;
        }

        private void writeHeader(Frame toWrite) throws IOException {
                Iterator<String> it = _FrameTags.keySet().iterator();
                Object[] param = {};

                while (it.hasNext()) {
                        String tag = it.next();
                        try {
                                Object o = _FrameTags.get(tag).invoke(toWrite, param);
                                o = Conversion.ConvertToExpeditee(_FrameTags.get(tag), o);
                                if (o != null) {
                                        writeLine(tag, o.toString());
                                }
                        } catch (Exception e) {
                                e.printStackTrace();
                        }
                }

                writeTerminator();
        }

        private void writeLine(String tag, String line) throws IOException {
                writeLine(tag + " " + line);
        }

        private void writeTerminator() throws IOException {
                writeLine(TERMINATOR + "\n");
        }

        // writes the given line out to the file
        private void writeLine(String line) throws IOException {
                // do not write empty lines
                if (line == null)
                        return;

                String toWrite = line + "\n";

                _writer.write(toWrite);
                _stringWriter.append(toWrite);
        }
        
        // writes the given Item out to the file
        // This method is not used to write out LINE items
        public void writeItem(Item item) throws IOException {
                if (_writer == null)
                        return;

                if (item.isLineEnd())
                        writeLineEnd(item);
                else if (!(item instanceof Line))
                        writeClass(item);
                // lines are saved at the end of the file
                // So dont worry about them in here
                else
                        System.out.println("Unknown Item: " + item.getID());

                writeLine("");
        }

        private List<Item> _lineEnds = new LinkedList<Item>();

        // Writes out a LineEnd to the file
        protected void writeLineEnd(Item point) throws IOException {
                _lineEnds.add(point);
                writeClass(point);
        }

        // writes out all lines to the file
        private void writeLineData() throws IOException {
                List<Line> seen = new LinkedList<Line>();

                // loop through all points stored
                for (int i = 0; i < _lineEnds.size(); i++) {
                        List<Line> lines = _lineEnds.get(i).getLines();

                        // if this point is part of one or more lines
                        if (lines != null && lines.size() > 0) {
                                for (Line line : lines) {

                                        // Brook: widget edges are not saved
                                        if (line instanceof WidgetEdge) {
                                                seen.add(line);
                                                continue;
                                        }

                                        // only output new lines that have not yet been output
                                        if (!seen.contains(line)) {
                                                writeLine("L", line.getID() + " " + line.getLineType());
                                                writeLine("s", line.getLineEnds());
                                                writeLine("");

                                                // add this line to the list of lines that have been
                                                // seen
                                                seen.add(line);
                                        }
                                }
                        }
                }
        }

        // writes out any constraints to the file
        private void writeConstraintData() throws IOException {
                // outputs any constraints the points have

                // loop through all the points
                while (_lineEnds.size() > 0) {
                        Item i = _lineEnds.get(0);

                        // if there are any constraints to write
                        if (i.getConstraints() != null) {
                                List<Constraint> constraints = i.getConstraints();

                                // do not write constraints that have already been
                                // written
                                for (Constraint c : constraints) {
                                        if (_lineEnds.contains(c.getStart())
                                                        && _lineEnds.contains(c.getEnd())) {
                                                writeLine("C", c.getID() + " " + c.getType());
                                                writeLine("s", c.getLineEnds());
                                                writeLine("");
                                        }

                                }
                        }
                        // remove the point from the list
                        _lineEnds.remove(0);
                }
        }

        @Override
        protected String finaliseFrame() throws IOException {
                _writer.flush();
                _writer.close();
                _writer = null;

                return "Frame successfully written to " + _filename;
        }

        private void writeClass(Object toWrite) throws IOException {
                Iterator<String> it = _ItemTags.keySet().iterator();
                Object[] param = {};

                while (it.hasNext()) {
                        String tag = it.next();
                        Method toRun = _ItemTags.get(tag);
                        Class<?> declarer = toRun.getDeclaringClass();
                        if (declarer.isAssignableFrom(toWrite.getClass())) {
                                try {
                                        Object o = toRun.invoke(toWrite, param);
                                        o = Conversion.ConvertToExpeditee(toRun, o);
                                        if (o != null) {
                                                if (o instanceof List) {
                                                        for (Object line : (List) o)
                                                                writeLine(tag, line.toString());
                                                } else
                                                        writeLine(tag, o.toString());
                                        }
                                } catch (Exception e) {
                                        e.printStackTrace();
                                }
                        }
                }
        }

        /**
         * Gets a string representation of the frame file contents.
         */
        public String getFileContents() {
                return _stringWriter.toString();
        }
}