LatexStreamReader.java

/*******************************************************************************
 *
 *	Copyright (C) 2008 Fujitsu Services Ltd.
 *
 *	Author: Nick Battle
 *
 *	This file is part of VDMJ.
 *
 *	VDMJ 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.
 *
 *	VDMJ 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 VDMJ.  If not, see <http://www.gnu.org/licenses/>.
 *
 ******************************************************************************/

package org.overture.parser.lex;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.Stack;

import org.overture.config.Settings;

/**
 * A class to read LaTeX encoded VDM files.
 */

public class LatexStreamReader extends InputStreamReader
{
	private Stack<Boolean> ifstack = new Stack<Boolean>();

	public LatexStreamReader(InputStream in, String charsetName)
			throws UnsupportedEncodingException
	{
		super(in, charsetName);
	}

	@Override
	public int read(char[] array) throws IOException
	{
		BufferedReader br = new BufferedReader(this);
		String line = br.readLine();

		boolean supress = false;
		boolean begin = false;
		int pos = 0;

		while (line != null)
		{
			String trimmed = line.trim();

			if (trimmed.startsWith("%"))
			{
				supress = true;
				// line = "";
			} else if (trimmed.startsWith("\\"))
			{
				if (trimmed.startsWith("\\begin{vdm_al}"))
				{
					supress = false;
					begin = true;
					// line = "";
				} else if (trimmed.startsWith("\\end{vdm_al}")
						|| trimmed.startsWith("\\section")
						|| trimmed.startsWith("\\subsection")
						|| trimmed.startsWith("\\document"))
				{
					supress = true;
					// line = "";
				}
			} else if (trimmed.startsWith("#"))
			{
				if (trimmed.startsWith("#ifdef"))
				{
					String label = trimmed.substring(6).trim();
					ifstack.push(supress);

					if (!supress && !label.equals(Settings.dialect.name()))
					{
						supress = true;
					}

					// line = "";
				} else if (trimmed.startsWith("#else"))
				{
					if (!ifstack.peek())
					{
						supress = !supress;
						// line = "";
					}
				} else if (trimmed.startsWith("#endif"))
				{
					supress = ifstack.pop();
					// line = "";
				}
			}

			if (!supress && !begin)
			{
				line.getChars(0, line.length(), array, pos);
				pos += line.length();
			} else
			{
				for (int i = 0; i < line.length(); i++)
				{
					array[pos++] = ' ';
				}

			}

			begin = false;
			if (pos < array.length)
			{
				array[pos++] = '\n';
				// //array[pos++] = ' ';
				// if(pos < array.length)
				// {
				//
				// }
			}
			line = br.readLine();
		}
		br.close();

		return pos;
	}

}