ca.hedlund.jiss.blocks.preprocessor.ListBlocksPreprocessor.java Source code

Introduction

Here is the source code for ca.hedlund.jiss.blocks.preprocessor.ListBlocksPreprocessor.java

Source

/*
 * jiss-blocks
 * Copyright (C) 2015, Gregory Hedlund <ghedlund@mun.ca>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package ca.hedlund.jiss.blocks.preprocessor;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.script.ScriptEngine;
import javax.script.ScriptEngineFactory;

import org.apache.commons.lang3.StringEscapeUtils;

import ca.hedlund.jiss.JissModel;
import ca.hedlund.jiss.JissPreprocessor;
import ca.hedlund.jiss.blocks.BlockManager;

public class ListBlocksPreprocessor implements JissPreprocessor {

    private final static String LIST_BLOCKS_REGEX = "\\:\\:block list( .*)?";

    private final Pattern LIST_BLOCKS_PATTERN = Pattern.compile(LIST_BLOCKS_REGEX);

    @Override
    public boolean preprocessCommand(JissModel jissModel, String orig, StringBuffer cmd) {
        if (!orig.startsWith("::block list"))
            return false;

        final ScriptEngine se = jissModel.getScriptEngine();
        final ScriptEngineFactory seFactory = se.getFactory();

        final boolean incnl = !seFactory.getOutputStatement("").startsWith("println");

        final List<String> blockInfoCmds = new ArrayList<String>();
        blockInfoCmds.add(seFactory.getOutputStatement("Available blocks:" + (incnl ? "\\n" : "")));

        final Matcher matcher = LIST_BLOCKS_PATTERN.matcher(orig);
        if (matcher.matches()) {
            final String blockNameRegex = matcher.group(1);
            final BlockManager bm = new BlockManager();

            for (String blockName : bm.getBlocks()) {
                boolean printBlock = true;
                if (blockNameRegex != null) {
                    printBlock = blockName.matches(blockNameRegex);
                }
                if (printBlock) {
                    blockInfoCmds.add(seFactory.getOutputStatement(blockName) + (incnl ? "\\n" : ""));
                }
            }
        }

        final String program = seFactory.getProgram(blockInfoCmds.toArray(new String[0]));
        cmd.setLength(0);
        cmd.append(StringEscapeUtils.unescapeJava(program));

        return false;
    }

}