michael@0: /**
michael@0:  * Copyright (c) 2012, Ben Fortuna
michael@0:  * All rights reserved.
michael@0:  *
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  *
michael@0:  *  o Redistributions of source code must retain the above copyright
michael@0:  * notice, this list of conditions and the following disclaimer.
michael@0:  *
michael@0:  *  o Redistributions in binary form must reproduce the above copyright
michael@0:  * notice, this list of conditions and the following disclaimer in the
michael@0:  * documentation and/or other materials provided with the distribution.
michael@0:  *
michael@0:  *  o Neither the name of Ben Fortuna nor the names of any other contributors
michael@0:  * may be used to endorse or promote products derived from this software
michael@0:  * without specific prior written permission.
michael@0:  *
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0:  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
michael@0:  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
michael@0:  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
michael@0:  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
michael@0:  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
michael@0:  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
michael@0:  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
michael@0:  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  */
michael@0: package net.fortuna.ical4j.data;
michael@0: 
michael@0: import java.io.IOException;
michael@0: import java.io.InputStream;
michael@0: import java.io.InputStreamReader;
michael@0: import java.io.Reader;
michael@0: import java.net.URISyntaxException;
michael@0: import java.nio.charset.Charset;
michael@0: import java.text.ParseException;
michael@0: import java.util.ArrayList;
michael@0: import java.util.Iterator;
michael@0: import java.util.List;
michael@0: 
michael@0: import net.fortuna.ical4j.model.Calendar;
michael@0: import net.fortuna.ical4j.model.CalendarException;
michael@0: import net.fortuna.ical4j.model.Component;
michael@0: import net.fortuna.ical4j.model.ComponentFactory;
michael@0: import net.fortuna.ical4j.model.Escapable;
michael@0: import net.fortuna.ical4j.model.Parameter;
michael@0: import net.fortuna.ical4j.model.ParameterFactory;
michael@0: import net.fortuna.ical4j.model.ParameterFactoryRegistry;
michael@0: import net.fortuna.ical4j.model.Property;
michael@0: import net.fortuna.ical4j.model.PropertyFactory;
michael@0: import net.fortuna.ical4j.model.PropertyFactoryRegistry;
michael@0: import net.fortuna.ical4j.model.TimeZone;
michael@0: import net.fortuna.ical4j.model.TimeZoneRegistry;
michael@0: import net.fortuna.ical4j.model.TimeZoneRegistryFactory;
michael@0: import net.fortuna.ical4j.model.component.VAvailability;
michael@0: import net.fortuna.ical4j.model.component.VEvent;
michael@0: import net.fortuna.ical4j.model.component.VTimeZone;
michael@0: import net.fortuna.ical4j.model.component.VToDo;
michael@0: import net.fortuna.ical4j.model.parameter.TzId;
michael@0: import net.fortuna.ical4j.model.property.DateListProperty;
michael@0: import net.fortuna.ical4j.model.property.DateProperty;
michael@0: import net.fortuna.ical4j.model.property.XProperty;
michael@0: import net.fortuna.ical4j.util.CompatibilityHints;
michael@0: import net.fortuna.ical4j.util.Constants;
michael@0: import net.fortuna.ical4j.util.Strings;
michael@0: 
michael@0: import org.apache.commons.logging.Log;
michael@0: import org.apache.commons.logging.LogFactory;
michael@0: 
michael@0: /**
michael@0:  * Parses and builds an iCalendar model from an input stream. Note that this class is not thread-safe.
michael@0:  * @version 2.0
michael@0:  * @author Ben Fortuna
michael@0:  * 
michael@0:  * <pre>
michael@0:  * $Id$
michael@0:  *
michael@0:  * Created: Apr 5, 2004
michael@0:  * </pre>
michael@0:  *
michael@0:  */
michael@0: public class CalendarBuilder {
michael@0: 
michael@0:     private static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");
michael@0: 
michael@0:     private final CalendarParser parser;
michael@0:     
michael@0:     private final ContentHandler contentHandler;
michael@0: 
michael@0:     private final TimeZoneRegistry tzRegistry;
michael@0:     
michael@0:     private List datesMissingTimezones;
michael@0: 
michael@0:     /**
michael@0:      * The calendar instance created by the builder.
michael@0:      */
michael@0:     protected Calendar calendar;
michael@0: 
michael@0:     /**
michael@0:      * The current component instance created by the builder.
michael@0:      */
michael@0:     protected Component component;
michael@0: 
michael@0:     /**
michael@0:      * The current sub-component instance created by the builder.
michael@0:      */
michael@0:     protected Component subComponent;
michael@0: 
michael@0:     /**
michael@0:      * The current property instance created by the builder.
michael@0:      */
michael@0:     protected Property property;
michael@0: 
michael@0:     /**
michael@0:      * Default constructor.
michael@0:      */
michael@0:     public CalendarBuilder() {
michael@0:         this(CalendarParserFactory.getInstance().createParser(), new PropertyFactoryRegistry(),
michael@0:                 new ParameterFactoryRegistry(), TimeZoneRegistryFactory.getInstance().createRegistry());
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new calendar builder using the specified calendar parser.
michael@0:      * @param parser a calendar parser used to parse calendar files
michael@0:      */
michael@0:     public CalendarBuilder(final CalendarParser parser) {
michael@0:         this(parser, new PropertyFactoryRegistry(), new ParameterFactoryRegistry(),
michael@0:                 TimeZoneRegistryFactory.getInstance().createRegistry());
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new calendar builder using the specified timezone registry.
michael@0:      * @param tzRegistry a timezone registry to populate with discovered timezones
michael@0:      */
michael@0:     public CalendarBuilder(final TimeZoneRegistry tzRegistry) {
michael@0:         this(CalendarParserFactory.getInstance().createParser(), new PropertyFactoryRegistry(),
michael@0:                 new ParameterFactoryRegistry(), tzRegistry);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new instance using the specified parser and registry.
michael@0:      * @param parser a calendar parser used to construct the calendar
michael@0:      * @param tzRegistry a timezone registry used to retrieve {@link TimeZone}s and
michael@0:      *  register additional timezone information found
michael@0:      * in the calendar
michael@0:      */
michael@0:     public CalendarBuilder(CalendarParser parser, TimeZoneRegistry tzRegistry) {
michael@0:         this(parser, new PropertyFactoryRegistry(), new ParameterFactoryRegistry(), tzRegistry);
michael@0:     }
michael@0:     
michael@0:     /**
michael@0:      * @param parser a custom calendar parser
michael@0:      * @param propertyFactoryRegistry registry for non-standard property factories
michael@0:      * @param parameterFactoryRegistry registry for non-standard parameter factories
michael@0:      * @param tzRegistry a custom timezone registry
michael@0:      */
michael@0:     public CalendarBuilder(CalendarParser parser, PropertyFactoryRegistry propertyFactoryRegistry,
michael@0:             ParameterFactoryRegistry parameterFactoryRegistry, TimeZoneRegistry tzRegistry) {
michael@0: 
michael@0:         this.parser = parser;
michael@0:         this.tzRegistry = tzRegistry;
michael@0:         this.contentHandler = new ContentHandlerImpl(ComponentFactory.getInstance(),
michael@0:                 propertyFactoryRegistry, parameterFactoryRegistry);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Builds an iCalendar model from the specified input stream.
michael@0:      * @param in an input stream to read calendar data from
michael@0:      * @return a calendar parsed from the specified input stream
michael@0:      * @throws IOException where an error occurs reading data from the specified stream
michael@0:      * @throws ParserException where an error occurs parsing data from the stream
michael@0:      */
michael@0:     public Calendar build(final InputStream in) throws IOException,
michael@0:             ParserException {
michael@0:         return build(new InputStreamReader(in, DEFAULT_CHARSET));
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Builds an iCalendar model from the specified reader. An <code>UnfoldingReader</code> is applied to the
michael@0:      * specified reader to ensure the data stream is correctly unfolded where appropriate.
michael@0:      * @param in a reader to read calendar data from
michael@0:      * @return a calendar parsed from the specified reader
michael@0:      * @throws IOException where an error occurs reading data from the specified reader
michael@0:      * @throws ParserException where an error occurs parsing data from the reader
michael@0:      */
michael@0:     public Calendar build(final Reader in) throws IOException, ParserException {
michael@0:         return build(new UnfoldingReader(in));
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Build an iCalendar model by parsing data from the specified reader.
michael@0:      * @param uin an unfolding reader to read data from
michael@0:      * @return a calendar parsed from the specified reader
michael@0:      * @throws IOException where an error occurs reading data from the specified reader
michael@0:      * @throws ParserException where an error occurs parsing data from the reader
michael@0:      */
michael@0:     public Calendar build(final UnfoldingReader uin) throws IOException,
michael@0:             ParserException {
michael@0:         // re-initialise..
michael@0:         calendar = null;
michael@0:         component = null;
michael@0:         subComponent = null;
michael@0:         property = null;
michael@0:         datesMissingTimezones = new ArrayList();
michael@0: 
michael@0:         parser.parse(uin, contentHandler);
michael@0: 
michael@0:         if (datesMissingTimezones.size() > 0 && tzRegistry != null) {
michael@0:             resolveTimezones();
michael@0:         }
michael@0:         
michael@0:         return calendar;
michael@0:     }
michael@0: 
michael@0:     private class ContentHandlerImpl implements ContentHandler {
michael@0: 
michael@0:         private final ComponentFactory componentFactory;
michael@0:         
michael@0:         private final PropertyFactory propertyFactory;
michael@0:         
michael@0:         private final ParameterFactory parameterFactory;
michael@0:         
michael@0:         public ContentHandlerImpl(ComponentFactory componentFactory, PropertyFactory propertyFactory,
michael@0:                 ParameterFactory parameterFactory) {
michael@0:             
michael@0:             this.componentFactory = componentFactory;
michael@0:             this.propertyFactory = propertyFactory;
michael@0:             this.parameterFactory = parameterFactory;
michael@0:         }
michael@0:         
michael@0:         public void endCalendar() {
michael@0:             // do nothing..
michael@0:         }
michael@0: 
michael@0:         public void endComponent(final String name) {
michael@0:             assertComponent(component);
michael@0: 
michael@0:             if (subComponent != null) {
michael@0:                 if (component instanceof VTimeZone) {
michael@0:                     ((VTimeZone) component).getObservances().add(subComponent);
michael@0:                 }
michael@0:                 else if (component instanceof VEvent) {
michael@0:                     ((VEvent) component).getAlarms().add(subComponent);
michael@0:                 }
michael@0:                 else if (component instanceof VToDo) {
michael@0:                     ((VToDo) component).getAlarms().add(subComponent);
michael@0:                 }
michael@0:                 else if (component instanceof VAvailability) {
michael@0:                     ((VAvailability) component).getAvailable().add(subComponent);
michael@0:                 }
michael@0:                 subComponent = null;
michael@0:             }
michael@0:             else {
michael@0:                 calendar.getComponents().add(component);
michael@0:                 if (component instanceof VTimeZone && tzRegistry != null) {
michael@0:                     // register the timezone for use with iCalendar objects..
michael@0:                     tzRegistry.register(new TimeZone((VTimeZone) component));
michael@0:                 }
michael@0:                 component = null;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         public void endProperty(final String name) {
michael@0:             assertProperty(property);
michael@0:             
michael@0:             // replace with a constant instance if applicable..
michael@0:             property = Constants.forProperty(property);
michael@0:             if (component != null) {
michael@0:                 if (subComponent != null) {
michael@0:                     subComponent.getProperties().add(property);
michael@0:                 }
michael@0:                 else {
michael@0:                     component.getProperties().add(property);
michael@0:                 }
michael@0:             }
michael@0:             else if (calendar != null) {
michael@0:                 calendar.getProperties().add(property);
michael@0:             }
michael@0: 
michael@0:             property = null;
michael@0:         }
michael@0: 
michael@0:         public void parameter(final String name, final String value) throws URISyntaxException {
michael@0:             assertProperty(property);
michael@0: 
michael@0:             // parameter names are case-insensitive, but convert to upper case to simplify further processing
michael@0:             final Parameter param = parameterFactory.createParameter(name.toUpperCase(), Strings.escapeNewline(value));
michael@0:             property.getParameters().add(param);
michael@0:             if (param instanceof TzId && tzRegistry != null && !(property instanceof XProperty)) {
michael@0:                 final TimeZone timezone = tzRegistry.getTimeZone(param.getValue());
michael@0:                 if (timezone != null) {
michael@0:                     updateTimeZone(property, timezone);
michael@0:                 } else {
michael@0:                     // VTIMEZONE may be defined later, so so keep
michael@0:                     // track of dates until all components have been
michael@0:                     // parsed, and then try again later
michael@0:                     datesMissingTimezones.add(property);
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0:         
michael@0:         /**
michael@0:          * {@inheritDoc}
michael@0:          */
michael@0:         public void propertyValue(final String value) throws URISyntaxException,
michael@0:                 ParseException, IOException {
michael@0:             
michael@0:             assertProperty(property);
michael@0: 
michael@0:             if (property instanceof Escapable) {
michael@0:                 property.setValue(Strings.unescape(value));
michael@0:             }
michael@0:             else {
michael@0:                 property.setValue(value);
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         /**
michael@0:          * {@inheritDoc}
michael@0:          */
michael@0:         public void startCalendar() {
michael@0:             calendar = new Calendar();
michael@0:         }
michael@0: 
michael@0:         /**
michael@0:          * {@inheritDoc}
michael@0:          */
michael@0:         public void startComponent(final String name) {
michael@0:             if (component != null) {
michael@0:                 subComponent = componentFactory.createComponent(name);
michael@0:             }
michael@0:             else {
michael@0:                 component = componentFactory.createComponent(name);
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         /**
michael@0:          * {@inheritDoc}
michael@0:          */
michael@0:         public void startProperty(final String name) {
michael@0:             // property names are case-insensitive, but convert to upper case to simplify further processing
michael@0:             property = propertyFactory.createProperty(name.toUpperCase());
michael@0:         }
michael@0:     }
michael@0:     
michael@0:     private void assertComponent(Component component) {
michael@0:         if (component == null) {
michael@0:             throw new CalendarException("Expected component not initialised");
michael@0:         }
michael@0:     }
michael@0:     
michael@0:     private void assertProperty(Property property) {
michael@0:         if (property == null) {
michael@0:             throw new CalendarException("Expected property not initialised");
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns the timezone registry used in the construction of calendars.
michael@0:      * @return a timezone registry
michael@0:      */
michael@0:     public final TimeZoneRegistry getRegistry() {
michael@0:         return tzRegistry;
michael@0:     }
michael@0: 
michael@0:     private void updateTimeZone(Property property, TimeZone timezone) {
michael@0:         try {
michael@0:             ((DateProperty) property).setTimeZone(timezone);
michael@0:         }
michael@0:         catch (ClassCastException e) {
michael@0:             try {
michael@0:                 ((DateListProperty) property).setTimeZone(timezone);
michael@0:             }
michael@0:             catch (ClassCastException e2) {
michael@0:                 if (CompatibilityHints.isHintEnabled(CompatibilityHints.KEY_RELAXED_PARSING)) {
michael@0:                     Log log = LogFactory.getLog(CalendarBuilder.class);
michael@0:                     log.warn("Error setting timezone [" + timezone.getID()
michael@0:                             + "] on property [" + property.getName()
michael@0:                             + "]", e);
michael@0:                 }
michael@0:                 else {
michael@0:                     throw e2;
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0:     }
michael@0:     
michael@0:     private void resolveTimezones() 
michael@0:         throws IOException {
michael@0:         
michael@0:         // Go through each property and try to resolve the TZID.
michael@0:         for (final Iterator it = datesMissingTimezones.iterator();it.hasNext();) {
michael@0:             final Property property = (Property) it.next();
michael@0:             final Parameter tzParam = property.getParameter(Parameter.TZID);
michael@0: 
michael@0:             // tzParam might be null: 
michael@0:             if (tzParam == null) {
michael@0:                 continue;
michael@0:             }
michael@0:             
michael@0:             //lookup timezone
michael@0:             final TimeZone timezone = tzRegistry.getTimeZone(tzParam.getValue());
michael@0:             
michael@0:             // If timezone found, then update date property
michael@0:             if (timezone != null) {
michael@0:                 // Get the String representation of date(s) as
michael@0:                 // we will need this after changing the timezone
michael@0:                 final String strDate = property.getValue();
michael@0:                 
michael@0:                 // Change the timezone
michael@0:                 if(property instanceof DateProperty) {
michael@0:                     ((DateProperty) property).setTimeZone(timezone);
michael@0:                 }
michael@0:                 else if(property instanceof DateListProperty) {
michael@0:                     ((DateListProperty) property).setTimeZone(timezone);
michael@0:                 }
michael@0:                     
michael@0:                 // Reset value
michael@0:                 try {
michael@0:                     property.setValue(strDate);
michael@0:                 } catch (ParseException e) {
michael@0:                     // shouldn't happen as its already been parsed
michael@0:                     throw new CalendarException(e);
michael@0:                 } catch (URISyntaxException e) {
michael@0:                     // shouldn't happen as its already been parsed
michael@0:                     throw new CalendarException(e);
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: }