/*
 * $Id: EntityCount.java,v 1.1 2008/02/06 10:42:59 linkconsulting Exp $
 *
 *  Copyright (c) 2004 The Open For Business Project - www.ofbiz.org
 *
 *  Permission is hereby granted, free of charge, to any person obtaining a
 *  copy of this software and associated documentation files (the "Software"),
 *  to deal in the Software without restriction, including without limitation
 *  the rights to use, copy, modify, merge, publish, distribute, sublicense,
 *  and/or sell copies of the Software, and to permit persons to whom the
 *  Software is furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice shall be included
 *  in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 *  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 *  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 *  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT
 *  OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
 *  THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package org.ofbiz.minilang.method.entityops;

import java.util.Map;

import org.ofbiz.base.util.Debug;
import org.ofbiz.base.util.GeneralException;
import org.ofbiz.base.util.UtilXml;
import org.ofbiz.base.util.collections.FlexibleMapAccessor;
import org.ofbiz.base.util.string.FlexibleStringExpander;
import org.ofbiz.entity.GenericDelegator;
import org.ofbiz.entity.condition.EntityCondition;
import org.ofbiz.entity.finder.EntityFinderUtil.Condition;
import org.ofbiz.entity.finder.EntityFinderUtil.ConditionExpr;
import org.ofbiz.entity.finder.EntityFinderUtil.ConditionList;
import org.ofbiz.entity.finder.EntityFinderUtil.ConditionObject;
import org.ofbiz.minilang.SimpleMethod;
import org.ofbiz.minilang.method.MethodContext;
import org.ofbiz.minilang.method.MethodOperation;
import org.w3c.dom.Element;

/**
 * Uses the delegator to find entity values by a condition
 *
 * @author     <a href="mailto:jonesde@ofbiz.org">David E. Jones</a>
 * @version    $Rev: 5462 $
 * @since      3.1
 */
public class EntityCount extends MethodOperation {
    
    public static final String module = EntityCount.class.getName();
    
    protected FlexibleStringExpander entityNameExdr;
    protected FlexibleStringExpander delegatorNameExdr;
    protected Condition whereCondition;
    protected Condition havingCondition;
    protected FlexibleMapAccessor countAcsr;

    public EntityCount(Element element, SimpleMethod simpleMethod) {
        super(element, simpleMethod);
        this.entityNameExdr = new FlexibleStringExpander(element.getAttribute("entity-name"));
        this.delegatorNameExdr = new FlexibleStringExpander(element.getAttribute("delegator-name"));
        this.countAcsr = new FlexibleMapAccessor(element.getAttribute("count-name"));
        
        // process condition-expr | condition-list
        Element conditionExprElement = UtilXml.firstChildElement(element, "condition-expr");
        Element conditionListElement = UtilXml.firstChildElement(element, "condition-list");
        Element conditionObjectElement = UtilXml.firstChildElement(element, "condition-object");
        if (conditionExprElement != null && conditionListElement != null) {
            throw new IllegalArgumentException("In entity find by condition element, cannot have condition-expr and condition-list sub-elements");
        }
        if (conditionExprElement != null) {
            this.whereCondition = new ConditionExpr(conditionExprElement);
        } else if (conditionListElement != null) {
            this.whereCondition = new ConditionList(conditionListElement);
        } else if (conditionObjectElement != null) {
            this.whereCondition = new ConditionObject(conditionObjectElement);
        }
        
        // process having-condition-list
        Element havingConditionListElement = UtilXml.firstChildElement(element, "having-condition-list");
        if (havingConditionListElement != null) {
            this.havingCondition = new ConditionList(havingConditionListElement);
        }
    }

    public boolean exec(MethodContext methodContext) {
        try {
            Map context = methodContext.getEnvMap();
            GenericDelegator delegator = methodContext.getDelegator();
            String entityName = this.entityNameExdr.expandString(context);
            String delegatorName = this.delegatorNameExdr.expandString(context);
            
            if (delegatorName != null && delegatorName.length() > 0) {
                delegator = GenericDelegator.getGenericDelegator(delegatorName);
            }

            // create whereEntityCondition from whereCondition
            EntityCondition whereEntityCondition = null;
            if (this.whereCondition != null) {
                whereEntityCondition = this.whereCondition.createCondition(context, entityName, delegator);
            }

            // create havingEntityCondition from havingCondition
            EntityCondition havingEntityCondition = null;
            if (this.havingCondition != null) {
                havingEntityCondition = this.havingCondition.createCondition(context, entityName, delegator);
            }
            
            long count = delegator.findCountByCondition(entityName, whereEntityCondition, havingEntityCondition);
            
            this.countAcsr.put(context, new Long(count));
        } catch (GeneralException e) {
            Debug.logError(e, module);
            String errMsg = "ERROR: Could not complete the " + simpleMethod.getShortDescription() + " process: " + e.getMessage();

            if (methodContext.getMethodType() == MethodContext.EVENT) {
                methodContext.putEnv(simpleMethod.getEventErrorMessageName(), errMsg);
                methodContext.putEnv(simpleMethod.getEventResponseCodeName(), simpleMethod.getDefaultErrorCode());
            } else if (methodContext.getMethodType() == MethodContext.SERVICE) {
                methodContext.putEnv(simpleMethod.getServiceErrorMessageName(), errMsg);
                methodContext.putEnv(simpleMethod.getServiceResponseMessageName(), simpleMethod.getDefaultErrorCode());
            }
            return false;
        }
        return true;
    }

    public String rawString() {
        // TODO: something more than the empty tag
        return "<entity-count/>";
    }
    public String expandedString(MethodContext methodContext) {
        // TODO: something more than a stub/dummy
        return this.rawString();
    }
}

