/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.tuscany.das.rdb.generator.impl;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;

import org.apache.log4j.Logger;
import org.apache.tuscany.das.rdb.config.Column;
import org.apache.tuscany.das.rdb.config.Relationship;
import org.apache.tuscany.das.rdb.config.Table;
import org.apache.tuscany.das.rdb.config.wrapper.MappingWrapper;
import org.apache.tuscany.das.rdb.config.wrapper.RelationshipWrapper;
import org.apache.tuscany.das.rdb.config.wrapper.TableWrapper;
import org.apache.tuscany.das.rdb.impl.InsertCommandImpl;
import org.apache.tuscany.das.rdb.impl.ParameterImpl;

import commonj.sdo.DataObject;
import commonj.sdo.Property;

public final class InsertGenerator extends BaseGenerator {

    public static final InsertGenerator INSTANCE = new InsertGenerator();

    private final Logger logger = Logger.getLogger(InsertGenerator.class);

    private InsertGenerator() {
        super();
    }

    public InsertCommandImpl getInsertCommand(MappingWrapper config, DataObject changedObject, Table t) {
        List parameters = new ArrayList();
        TableWrapper table = new TableWrapper(t);
        StringBuffer statement = new StringBuffer("insert into ");
        //JIRA-952
        if(config.getConfig().isDatabaseSchemaNameSupported()){
        	statement.append(t.getSchemaName()+"."+t.getTableName());
        }
        else{
        statement.append(t.getTableName());
        }
        HashSet changedProperties = getAttributeProperties(changedObject, config, table);
        Iterator i;
        if ( changedProperties.isEmpty() ) {
            i = changedObject.getType().getProperties().iterator();
        } else {
            i = changedProperties.iterator();
        }

        List attributes = new ArrayList();
        List generatedKeys = new ArrayList();
        while (i.hasNext()) {
            Property attr = (Property) i.next();
            if ( attr.getType().isDataType()) {
                if (table.isGeneratedColumnProperty(attr.getName())) {
                 generatedKeys.add(attr.getName());
             } else {
                 attributes.add(attr.getName());
                    parameters.add(changedObject.getType().getProperty(attr.getName()));
             }
            }
        }

        statement.append("(");
        Iterator attrs = attributes.iterator();
        while (attrs.hasNext()) {
            String name = (String) attrs.next();
            statement.append("");
            Column c = config.getColumnByPropertyName(t, name);
            statement.append(c == null ? name : c.getColumnName());
            if (attrs.hasNext()) {
                statement.append(", ");
            } else {
                statement.append(")");
            }
        }

        statement.append(" values (");
        for (int idx = 1; idx <= attributes.size(); idx++) {
            statement.append('?');
            if (idx < attributes.size()) {
                statement.append(", ");
            } else {
                statement.append(")");
            }
        }

        InsertCommandImpl cmd = new InsertCommandImpl(statement.toString(), 
                (String[]) generatedKeys.toArray(new String[0]));
        Iterator params = parameters.iterator();
        for (int idx = 1; params.hasNext(); idx++) {
            Property property = (Property) params.next();
            ParameterImpl p = new ParameterImpl();
            p.setName(property.getName());
            p.setType(property.getType());
            p.setConverter(getConverter(table.getConverter(property.getName())));
            p.setIndex(idx);
            cmd.addParameter(p);

        }
        if (this.logger.isDebugEnabled()) {
            this.logger.debug(statement.toString());
        }

        return cmd;

    }

    private HashSet getAttributeProperties(DataObject obj, MappingWrapper config, TableWrapper tw) {
        HashSet fields = new HashSet();
        Iterator i = obj.getType().getProperties().iterator();
        while (i.hasNext()) {
            Property p = (Property) i.next();
            if (p.getType().isDataType()) {
                if (obj.isSet(p)) {
                    if (fields.add(p) == false) {
                        throw new RuntimeException("Foreign key properties should not be set when the corrsponding relationship has changed");
                    }
                }
            } else {
                if (obj.isSet(p)) {
                    Relationship relationship = config.getRelationshipByReference(p);
                    if ((p.getOpposite() != null && p.getOpposite().isMany()) 
                            || (hasState(tw, relationship, obj))) {
                        RelationshipWrapper r = new RelationshipWrapper(relationship);
                        Iterator keys = r.getForeignKeys().iterator();
                        while (keys.hasNext()) {
                            String key = (String) keys.next();
                            String keyProperty = config.getColumnPropertyName(tw.getTableName(), key);
                            Property keyProp = obj.getType().getProperty(keyProperty);
                            if ( keyProp == null ) 
                                throw new RuntimeException("Invalid foreign key column: " + key);
                            if (fields.add(keyProp) == false) {
                                throw new RuntimeException("Foreign key properties should not be set when the corresponding relationship has changed");
                            }
                        }
                    }

                }
            }
        }

        return fields;

    }

    private boolean hasState(TableWrapper tw, Relationship rel, DataObject changedObject) {

        if (!rel.isMany()) {
                   
            RelationshipWrapper rw = new RelationshipWrapper(rel);
            if ((rel.getForeignKeyTable().equals(tw.getTableName())) 
                    && (Collections.disjoint(tw.getPrimaryKeyProperties(), rw.getForeignKeys()))) {
                return true;
            }
        }

        return false;
    }

}