/*
 * $Id: EntityConditionBase.java,v 1.1 2008/02/06 10:43:10 linkconsulting Exp $
 *
 *  Copyright (c) 2002-2005 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.entity.condition;

import java.io.Serializable;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import javolution.util.FastList;
import javolution.util.FastMap;

import org.ofbiz.entity.config.DatasourceInfo;
import org.ofbiz.entity.jdbc.SqlJdbcUtil;
import org.ofbiz.entity.model.ModelEntity;
import org.ofbiz.entity.model.ModelField;
import org.ofbiz.entity.model.ModelViewEntity;
import org.ofbiz.entity.model.ModelViewEntity.ModelAlias;

/**
 * Represents the conditions to be used to constrain a query
 * <br/>An EntityCondition can represent various type of constraints, including:
 * <ul>
 *  <li>EntityConditionList: a list of EntityConditions, combined with the operator specified
 *  <li>EntityExpr: for simple expressions or expressions that combine EntityConditions
 *  <li>EntityFieldMap: a map of fields where the field (key) equals the value, combined with the operator specified
 * </ul>
 * These can be used in various combinations using the EntityConditionList and EntityExpr objects.
 *
 * @author     <a href="mailto:jonesde@ofbiz.org">David E. Jones</a>
 * @version    $Rev: 5462 $
 * @since      2.0
 */
public abstract class EntityConditionBase implements Serializable {

    public static final List emptyList = Collections.unmodifiableList(FastList.newInstance());
    public static final Map emptyMap = Collections.unmodifiableMap(FastMap.newInstance());

    protected ModelField getField(ModelEntity modelEntity, String fieldName) {
        ModelField modelField = null;
        if (modelEntity != null) {
            modelField = (ModelField) modelEntity.getField(fieldName);
        }
        return modelField;
    }

    protected String getColName(Map tableAliases, ModelEntity modelEntity, String fieldName, boolean includeTableNamePrefix, DatasourceInfo datasourceInfo) {
        if (modelEntity == null) return fieldName;
        return getColName(tableAliases, modelEntity, getField(modelEntity, fieldName), fieldName, includeTableNamePrefix, datasourceInfo);
    }

    protected String getColName(ModelField modelField, String fieldName) {
        String colName = null;
        if (modelField != null) {
            colName = modelField.getColName();
        } else {
            colName = (String) fieldName;
        }
        return colName;
    }

    protected String getColName(Map tableAliases, ModelEntity modelEntity, ModelField modelField, String fieldName, boolean includeTableNamePrefix, DatasourceInfo datasourceInfo) {
        if (modelEntity == null || modelField == null) return fieldName;

        // if this is a view entity and we are configured to alias the views, use the alias here instead of the composite (ie table.column) field name 
        if (datasourceInfo != null && datasourceInfo.aliasViews && modelEntity instanceof ModelViewEntity) {
            ModelViewEntity modelViewEntity = (ModelViewEntity) modelEntity;
            ModelAlias modelAlias = modelViewEntity.getAlias(fieldName);
            if (modelAlias != null) {
                return modelAlias.getColAlias();
            }
        }
        
        String colName = getColName(modelField, fieldName);
        if (includeTableNamePrefix && datasourceInfo != null) {
            String tableName = modelEntity.getTableName(datasourceInfo);
            if (tableAliases.containsKey(tableName)) {
                tableName = (String) tableAliases.get(tableName);
            }
            colName = tableName + "." + colName;
        }
        return colName;
    }

    protected void addValue(StringBuffer buffer, ModelField field, Object value, List params) {
        SqlJdbcUtil.addValue(buffer, params == null ? null : field, value, params);
    }

    public boolean equals(Object obj) {
        throw new UnsupportedOperationException("equals:" + getClass().getName());
    }

    public int hashCode() {
        throw new UnsupportedOperationException("hashCode: " + getClass().getName());
    }

    protected static boolean equals(Object o1, Object o2) {
        return o1 == null ? o2 == null : o1.equals(o2);
    }

    protected static int hashCode(Object o) {
        return o != null ? o.hashCode() : 0;
    }

    public static Boolean castBoolean(boolean result) {
        return result ? Boolean.TRUE : Boolean.FALSE;
    }
}
