org.eclipse.birt.core.script.ScriptableParameter Maven / Gradle / Ivy

/*******************************************************************************
 * Copyright (c) 2004 Actuate Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/

package org.eclipse.birt.core.script;

import java.util.Map;

import org.eclipse.birt.core.i18n.CoreMessages;
import org.eclipse.birt.core.i18n.ResourceConstants;
import org.mozilla.javascript.Callable;
import org.mozilla.javascript.Context;
import org.mozilla.javascript.JavaScriptException;
import org.mozilla.javascript.Scriptable;
import org.mozilla.javascript.Wrapper;

public class ScriptableParameter extends BaseScriptable implements Wrapper
{

	private Map parameters;
	private String parameterName;

	private final static String JS_CLASS_NAME = "ScriptableParameters";

	public final static String FIELD_VALUE = "value";
	public final static String FIELD_DISPLAY_TEXT = "displayText";

	public ScriptableParameter( Map parameters, String parameterName,
			Scriptable parent )
	{
		setParentScope( parent );
		this.parameters = parameters;
		this.parameterName = parameterName;
	}

	public Object get( String name, Scriptable scope )
	{
		ParameterAttribute parameter = getParameterAttribute( name );
		if ( FIELD_VALUE.equals( name ) )
		{
			return parameter.getValue( );
		}
		else if ( FIELD_DISPLAY_TEXT.equals( name ) )
		{
			return parameter.getDisplayText( );
		}
		Object value = parameter.getValue( );
		Scriptable jsValue = Context.toObject( value, scope );
		Scriptable prototype = jsValue.getPrototype( );
		if( prototype != null )
		{
			Object property = jsValue.getPrototype( ).get( name, jsValue );
			if ( property instanceof Callable )
			{
				Callable callable = (Callable) property;
				return new JsValueCallable( callable, jsValue );
			}
			return jsValue.get( name, jsValue );
		}
		else
		{
			return jsValue.get( name, jsValue );
		}
	}

	public static class JsValueCallable implements Callable
	{
		private Callable impl;
		private Scriptable value;

		public JsValueCallable( Callable callable, Scriptable value)
		{
			this.impl = callable;
			this.value = value;
		}
		
		public Object call( Context cx, Scriptable scope, Scriptable thisObj,
				Object[] args )
		{
			return impl.call( cx, scope, value, args );
		}
	}
	
	private ParameterAttribute getParameterAttribute( String name )
	{
		Object value = parameters.get( parameterName );
		if ( value == null )
		{
			String errorMessage = CoreMessages.getFormattedString( ResourceConstants.JAVASCRIPT_PARAMETER_NOT_EXIST,
					name );
			throw new JavaScriptException( errorMessage, "", -1 );
		}
		assert value instanceof ParameterAttribute;
		ParameterAttribute parameter = (ParameterAttribute) value;
		return parameter;
	}

	public Object getDefaultValue( Class hint )
	{
		Object value = parameters.get( parameterName );
		if ( value == null )
		{
			return null;
		}
		assert value instanceof ParameterAttribute;
		ParameterAttribute parameter = (ParameterAttribute) value;
		return parameter.getValue( );
	}

	public boolean has( String name, Scriptable scope )
	{
		if ( FIELD_VALUE.equals( name ) || FIELD_DISPLAY_TEXT.equals( name ) )
		{
			return true;
		}
		ParameterAttribute parameter = getParameterAttribute( name );
		Scriptable jsValue = Context.toObject( parameter.getValue( ), scope );
		if ( jsValue != null )
		{
			return jsValue.has( name, scope );
		}
		return false;
	}

	public void put( String name, Scriptable scope, Object value )
	{
		Object parameterValue = parameters.get( parameterName );
		if ( parameterValue == null )
		{
			return;
		}
		assert parameterValue instanceof ParameterAttribute;
		ParameterAttribute parameter = (ParameterAttribute) parameterValue;
		
		if ( value instanceof Wrapper )
		{
			value = ( (Wrapper) value ).unwrap( );
		}
		
		if ( FIELD_VALUE.equals( name ) )
		{
			parameter.setValue( value );
		}
		else if ( FIELD_DISPLAY_TEXT.equals( name ) )
		{
			parameter.setDisplayText( (String) value );
		}
	}

	public String getClassName( )
	{
		return JS_CLASS_NAME;
	}

	public Object unwrap( )
	{
		Object value = parameters.get( parameterName );
		if ( value != null )
		{
			return ( (ParameterAttribute) value ).getValue( );
		}
		return null;
	}
}