// Copyright 2007, 2008, 2009, 2010 The Apache Software Foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package org.apache.tapestry5.corelib.components;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import org.apache.tapestry5.*;
import org.apache.tapestry5.annotations.Environmental;
import org.apache.tapestry5.annotations.Events;
import org.apache.tapestry5.annotations.Import;
import org.apache.tapestry5.annotations.Parameter;
import org.apache.tapestry5.annotations.RequestParameter;
import org.apache.tapestry5.corelib.base.AbstractField;
import org.apache.tapestry5.ioc.Messages;
import org.apache.tapestry5.ioc.annotations.Inject;
import org.apache.tapestry5.ioc.internal.util.InternalUtils;
import org.apache.tapestry5.json.JSONObject;
import org.apache.tapestry5.services.ComponentDefaultProvider;
import org.apache.tapestry5.services.Request;
import org.apache.tapestry5.services.javascript.JavaScriptSupport;
/**
* A component used to collect a provided date from the user using a client-side JavaScript calendar. Non-JavaScript
* clients can simply type into a text field.
* <p/>
* One wierd aspect here is that, because client-side JavaScript formatting and parsing is so limited, we (currently)
* use Ajax to send the user's input to the server for parsing (before raising the popup) and formatting (after closing
* the popup). Weird and inefficient, but easier than writing client-side JavaScript for that purpose.
* <p/>
* Tapestry's DateField component is a wrapper around <a
* href="http://webfx.eae.net/dhtml/datepicker/datepicker.html">WebFX DatePicker</a>.
*/
// TODO: More testing; see https://issues.apache.org/jira/browse/TAPESTRY-1844
@Import(stack = "core-datefield")
@Events(EventConstants.VALIDATE)
public class DateField extends AbstractField
{
/**
* The value parameter of a DateField must be a {@link java.util.Date}.
*/
@Parameter(required = true, principal = true, autoconnect = true)
private Date value;
/**
* The format used to format <em>and parse</em> dates. This is typically specified as a string which is coerced to a
* DateFormat. You should be aware that using a date format with a two digit year is problematic: Java (not
* Tapestry) may get confused about the century.
*/
@Parameter(required = true, allowNull = false, defaultPrefix = BindingConstants.LITERAL)
private DateFormat format;
/**
* If true, then the text field will be hidden, and only the icon for the date picker will be visible. The default
* is false.
*/
@Parameter
private boolean hideTextField;
/**
* The object that will perform input validation (which occurs after translation). The translate binding prefix is
* generally used to provide this object in a declarative fashion.
*/
@Parameter(defaultPrefix = BindingConstants.VALIDATE)
@SuppressWarnings("unchecked")
private FieldValidator<Object> validate;
@Parameter(defaultPrefix = BindingConstants.ASSET, value = "datefield.gif")
private Asset icon;
/**
* Used to override the component's message catalog.
*
* @since 5.2.0.0
*/
@Parameter("componentResources.messages")
private Messages messages;
@Environmental
private JavaScriptSupport support;
@Environmental
private ValidationTracker tracker;
@Inject
private ComponentResources resources;
@Inject
private Request request;
@Inject
private Locale locale;
@Inject
private ComponentDefaultProvider defaultProvider;
@Inject
private FieldValidationSupport fieldValidationSupport;
private static final String RESULT = "result";
private static final String ERROR = "error";
private static final String INPUT_PARAMETER = "input";
DateFormat defaultFormat()
{
DateFormat shortDateFormat = DateFormat.getDateInstance(DateFormat.SHORT, locale);
if (shortDateFormat instanceof SimpleDateFormat)
{
SimpleDateFormat simpleDateFormat = (SimpleDateFormat) shortDateFormat;
String pattern = simpleDateFormat.toPattern();
String revised = pattern.replaceAll("([^y])yy$", "$1yyyy");
return new SimpleDateFormat(revised);
}
return shortDateFormat;
}
/**
* Computes a default value for the "validate" parameter using {@link ComponentDefaultProvider}.
*/
final Binding defaultValidate()
{
return defaultProvider.defaultValidatorBinding("value", resources);
}
/**
* Ajax event handler, used when initiating the popup. The client sends the input value form the field to the server
* to parse it according to the server-side format. The response contains a "result" key of the formatted date in a
* format acceptable to the JavaScript Date() constructor. Alternately, an "error" key indicates the the input was
* not formatted correct.
*/
JSONObject onParse(@RequestParameter(INPUT_PARAMETER)
String input)
{
JSONObject response = new JSONObject();
try
{
Date date = format.parse(input);
response.put(RESULT, date.getTime());
}
catch (ParseException ex)
{
response.put(ERROR, ex.getMessage());
}
return response;
}
/**
* Ajax event handler, used after the client-side popup completes. The client sends the date, formatted as
* milliseconds since the epoch, to the server, which reformats it according to the server side format and returns
* the result.
*/
JSONObject onFormat(@RequestParameter(INPUT_PARAMETER)
String input)
{
JSONObject response = new JSONObject();
try
{
long millis = Long.parseLong(input);
Date date = new Date(millis);
response.put(RESULT, format.format(date));
}
catch (NumberFormatException ex)
{
response.put(ERROR, ex.getMessage());
}
return response;
}
void beginRender(MarkupWriter writer)
{
String value = tracker.getInput(this);
if (value == null)
value = formatCurrentValue();
String clientId = getClientId();
String triggerId = clientId + "-trigger";
writer.element("input",
"type", hideTextField ? "hidden" : "text",
"name", getControlName(),
"id", clientId,
"value", value);
writeDisabled(writer);
putPropertyNameIntoBeanValidationContext("value");
validate.render(writer);
removePropertyNameFromBeanValidationContext();
resources.renderInformalParameters(writer);
decorateInsideField();
writer.end();
// Now the trigger icon.
writer.element("img",
"id", triggerId,
"class", "t-calendar-trigger",
"src", icon.toClientURL(),
"alt", "[Show]");
writer.end(); // img
JSONObject spec = new JSONObject();
spec.put("field", clientId);
spec.put("parseURL", resources.createEventLink("parse").toURI());
spec.put("formatURL", resources.createEventLink("format").toURI());
support.addInitializerCall("dateField", spec);
}
private void writeDisabled(MarkupWriter writer)
{
if (isDisabled())
writer.attributes("disabled", "disabled");
}
private String formatCurrentValue()
{
if (value == null)
return "";
return format.format(value);
}
@Override
protected void processSubmission(String elementName)
{
String value = request.getParameter(elementName);
tracker.recordInput(this, value);
Date parsedValue = null;
try
{
if (InternalUtils.isNonBlank(value))
parsedValue = format.parse(value);
}
catch (ParseException ex)
{
tracker.recordError(this, messages.format("date-value-not-parseable", value));
return;
}
putPropertyNameIntoBeanValidationContext("value");
try
{
fieldValidationSupport.validate(parsedValue, resources, validate);
this.value = parsedValue;
}
catch (ValidationException ex)
{
tracker.recordError(this, ex.getMessage());
}
removePropertyNameFromBeanValidationContext();
}
void injectResources(ComponentResources resources)
{
this.resources = resources;
}
@Override
public boolean isRequired()
{
return validate.isRequired();
}
}