RelevantBuilder.java

package org.openrosa.client.xforms;

import java.util.Vector;

import org.openrosa.client.model.Condition;
import org.openrosa.client.model.FormDef;
import org.openrosa.client.model.IFormElement;
import org.openrosa.client.model.QuestionDef;
import org.openrosa.client.model.SkipRule;
import org.openrosa.client.model.ModelConstants;
import org.openrosa.client.model.ValidationRule;
import org.openrosa.client.xforms.XformBuilderUtil;
import org.openrosa.client.xforms.XformConstants;

import com.google.gwt.xml.client.Document;
import com.google.gwt.xml.client.Element;


/**
 * Builds relevant attributes of xforms documents from skip rule definition objects.
 * 
 * @author daniel
 *
 */
public class RelevantBuilder {

	/**
	 * All methods in this class are static and hence we expect no external
	 * Instantiation of this class.
	 */
	private RelevantBuilder(){

	}
	
	/**
	 * Takes in a SkipRule and returns the completed Relevant
	 * attribute value
	 * @param rule
	 * @param formDef - the underlying formdef for this mess.
	 * @return - The reconstructed relevant attribute.
	 */
	public static String fromSkipRule2String(SkipRule rule, FormDef formDef){
		String relevant = "";
		if(rule == null){
			return relevant;
		}
		Vector conditions  = rule.getConditions();
		for(int i=0; i<conditions.size(); i++){
			if(relevant.length() > 0){
				relevant += XformBuilderUtil.getConditionsOperatorText(rule.getConditionsOperator());
			}
			relevant += fromCondition2Xform((Condition)conditions.elementAt(i),formDef,rule.getAction());
		}
		return relevant;
	}
	

	
	/**
	 * A slightly higher level function that figures out
	 * if the question associated with this rule has
	 * an 'advanced' relevant or if it should be extracted
	 * out of the SkipRule in the traditional way (for less
	 * complex relevants)
	 * @param rule The SkipRule associated with the specified skip rule.
	 * @param qID The internal ID for the question for which the relevant will be generated
	 * @param formDef
	 * @return
	 */
	public static String getRelevantFromRule(SkipRule rule, int qID, FormDef formDef){
		IFormElement elementDef = formDef.getElement(qID);
		String relevant = "";
		if(elementDef.hasAdvancedRelevant()){
			relevant = elementDef.getAdvancedRelevant();
			if(relevant != null){
				return relevant;
			}else{
				return "";
			}
		}
		
		
		Vector conditions  = rule.getConditions();
		for(int i=0; i<conditions.size(); i++){
			if(relevant.length() > 0){
				relevant += XformBuilderUtil.getConditionsOperatorText(rule.getConditionsOperator());
			}
			relevant += fromCondition2Xform((Condition)conditions.elementAt(i),formDef,rule.getAction());
		}
		
		
		return relevant;
	}
	/**
	 * Converts a skip rule definition object to xforms.
	 * 
	 * @param rule the skip rule definition object
	 * @param formDef the form definition.
	 */
	public static void fromSkipRule2Xform(SkipRule rule, FormDef formDef, Document doc){
		Vector actionTargets =  rule.getActionTargets();
		for(int i=0; i<actionTargets.size(); i++){
			int id = ((Integer)actionTargets.elementAt(i)).intValue();
			IFormElement elementDef = formDef.getElement(id);
			if(elementDef == null)
				continue;

			Element node = elementDef.getBindNode();
			if(node == null){
				node = createBindNodeAndAddToDoc(elementDef.getDataNodesetPath(), elementDef, formDef, doc);
			}
			
			String relevant = getRelevantFromRule(rule, id, formDef);
//			relevant = relevant.replace(">", ">").replace("<", "<");
			if(relevant.trim().length() == 0){
				node.removeAttribute(XformConstants.ATTRIBUTE_NAME_RELEVANT);
				node.removeAttribute(XformConstants.ATTRIBUTE_NAME_ACTION);
				node.removeAttribute(XformConstants.ATTRIBUTE_NAME_REQUIRED);
			}
			else{
				node.setAttribute(XformConstants.ATTRIBUTE_NAME_RELEVANT, relevant);

				String value = XformConstants.ATTRIBUTE_VALUE_ENABLE;
				if((rule.getAction() & ModelConstants.ACTION_ENABLE) != 0)
					value = XformConstants.ATTRIBUTE_VALUE_ENABLE;
				else if((rule.getAction() & ModelConstants.ACTION_DISABLE) != 0)
					value = XformConstants.ATTRIBUTE_VALUE_DISABLE;
				else if((rule.getAction() & ModelConstants.ACTION_SHOW) != 0)
					value = XformConstants.ATTRIBUTE_VALUE_SHOW;
				else if((rule.getAction() & ModelConstants.ACTION_HIDE) != 0)
					value = XformConstants.ATTRIBUTE_VALUE_HIDE;
				
				if((rule.getAction() & ModelConstants.ACTION_MAKE_MANDATORY) != 0)
					value = XformConstants.XPATH_VALUE_TRUE;
				else if((rule.getAction() & ModelConstants.ACTION_MAKE_OPTIONAL) != 0)
					value = XformConstants.XPATH_VALUE_FALSE;
				//node.setAttribute(XformConstants.ATTRIBUTE_NAME_REQUIRED, value);
			}
		}
	}
	
	private static Element createBindNodeAndAddToDoc(String nodeSetVal,IFormElement elementDef, FormDef formDef, Document doc){
		Element node = doc
			.createElement("bind");
		node.setAttribute("nodeset", nodeSetVal);
		node.setAttribute("id",elementDef.getQuestionID());
		elementDef.setBindNode(node);
		formDef.getModelNode().appendChild(node);
		
		return node;
	}
	
	
	/**
	 * Creates an xforms representation of a skip rule condition.
	 * 
	 * @param condition the condition object.
	 * @param formDef the form definition object to which the skip rule belongs.
	 * @param action the skip rule action to its target questions.
	 * @return the condition xforms representation.
	 */
	private static String fromCondition2Xform(Condition condition, FormDef formDef, int action){
		String attrText = null;

		QuestionDef questionDef = formDef.getQuestion(condition.getQuestionId());
		if(questionDef != null){
			attrText = questionDef.getQuestionID();
			if(!attrText.contains(formDef.getQuestionID())){
				attrText = "/" + formDef.getQuestionID() + "/" + questionDef.getQuestionID();
			}
			
			String value = " '" + condition.getValue() + "'";
			if(questionDef.getDataType() == QuestionDef.QTN_TYPE_BOOLEAN || questionDef.getDataType() == QuestionDef.QTN_TYPE_DECIMAL || 
					questionDef.getDataType() == QuestionDef.QTN_TYPE_NUMERIC || questionDef.getDataType() == QuestionDef.QTN_TYPE_LONG){
				value = " " + condition.getValue();
			}
			
			attrText += " " + XformBuilderUtil.getXpathOperator(condition.getOperator(),action)+value;
		}
		return attrText;
	}
}