/**
* Copyright (C) 2009 eXo Platform SAS.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.exoplatform.groovyscript;
import org.gatein.common.io.UndeclaredIOException;
import java.io.IOException;
import java.io.PushbackReader;
import java.io.Reader;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
* @version $Revision$
*/
public class TemplateParser
{
private enum Status
{
TEXT,
EXPR,
SCRIPTLET,
START_ANGLE,
SCRIPLET_OR_EXPR,
MAYBE_SCRIPLET_END,
MAYBE_EXPR_END,
MAYBE_GSTRING_EXPR,
GSTRING_CURLY_EXPR,
GSTRING_EXPR
}
public List<TemplateSection> parse(String s)
{
try
{
return parse(new StringReader(s));
}
catch (IOException e)
{
throw new UndeclaredIOException(e);
}
}
public List<TemplateSection> parse(Reader tmp) throws IOException
{
PushbackReader reader = new PushbackReader(tmp);
//
ArrayList<TemplateSection> sections = new ArrayList<TemplateSection>();
StringBuilder accumulator = new StringBuilder();
//
int lineNumber = 1;
int colNumber = 1;
Position pos = new Position(1, 1);
Status status = Status.TEXT;
int i;
while ((i = reader.read()) != -1)
{
char c = (char)i;
//
if (c == '\r')
{
// On Windows, "\r\n" is a new line
int j = reader.read();
if (j != -1)
{
char c2 = (char)j;
if (c2 == '\n')
{
c = '\n';
}
else
{
reader.unread(j);
}
}
}
// Update current position
if (c == '\n')
{
colNumber = 1;
lineNumber++;
}
else
{
colNumber++;
}
//
switch (status)
{
case TEXT:
if (c == '<')
{
status = Status.START_ANGLE;
}
else if (c == '$')
{
status = Status.MAYBE_GSTRING_EXPR;
}
else
{
accumulator.append(c);
}
break;
case EXPR:
if (c == '%')
{
status = Status.MAYBE_EXPR_END;
}
else
{
accumulator.append(c);
}
break;
case SCRIPTLET:
if (c == '%')
{
status = Status.MAYBE_SCRIPLET_END;
}
else
{
accumulator.append(c);
}
break;
case START_ANGLE:
if (c == '%')
{
status = Status.SCRIPLET_OR_EXPR;
}
else
{
status = Status.TEXT;
accumulator.append('<').append(c);
}
break;
case SCRIPLET_OR_EXPR:
if (accumulator.length() > 0)
{
sections.add(new TemplateSection(SectionType.STRING, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
}
if (c == '=')
{
status = Status.EXPR;
}
else if (c == '%')
{
status = Status.MAYBE_SCRIPLET_END;
}
else
{
status = Status.SCRIPTLET;
accumulator.append(c);
}
break;
case MAYBE_SCRIPLET_END:
if (c == '>')
{
sections.add(new TemplateSection(SectionType.SCRIPTLET, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
//
status = Status.TEXT;
}
else if (c == '%')
{
accumulator.append('%');
}
else
{
status = Status.SCRIPTLET;
accumulator.append('%').append(c);
}
break;
case MAYBE_EXPR_END:
if (c == '>')
{
sections.add(new TemplateSection(SectionType.EXPR, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
//
status = Status.TEXT;
}
else if (c == '%')
{
accumulator.append('%');
}
else
{
status = Status.EXPR;
accumulator.append('%').append(c);
}
break;
case MAYBE_GSTRING_EXPR:
if (c == '{')
{
if (accumulator.length() > 0)
{
sections.add(new TemplateSection(SectionType.STRING, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
}
status = Status.GSTRING_CURLY_EXPR;
}
else if (Character.isJavaIdentifierStart(c))
{
if (accumulator.length() > 0)
{
sections.add(new TemplateSection(SectionType.STRING, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
}
status = Status.GSTRING_EXPR;
accumulator.append(c);
}
else
{
accumulator.append('$').append(c);
}
break;
case GSTRING_CURLY_EXPR:
if (c == '}')
{
sections.add(new TemplateSection(SectionType.EXPR, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
//
status = Status.TEXT;
}
else
{
accumulator.append(c);
}
break;
case GSTRING_EXPR:
if (c == '.' || Character.isJavaIdentifierPart(c))
{
accumulator.append(c);
}
else
{
sections.add(new TemplateSection(SectionType.EXPR, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
//
status = Status.TEXT;
accumulator.append(c);
}
break;
default:
throw new AssertionError();
}
}
// Last section
if (accumulator.length() > 0)
{
switch (status)
{
case TEXT:
sections.add(new TemplateSection(SectionType.STRING, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
break;
case GSTRING_EXPR:
sections.add(new TemplateSection(SectionType.EXPR, accumulator.toString(), pos));
accumulator.setLength(0);
pos = new Position(colNumber, lineNumber);
break;
default:
throw new AssertionError();
}
}
//
return Collections.unmodifiableList(sections);
}
}