/*
 * Copyright 2016-2018 shardingsphere.io.
 * <p>
 * Licensed 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.
 * </p>
 */

package io.shardingsphere.core.parsing.antler.phrase.visitor;

import java.util.List;

import org.antlr.v4.runtime.ParserRuleContext;

import io.shardingsphere.core.parsing.antler.sql.ddl.AlterTableStatement;
import io.shardingsphere.core.parsing.antler.sql.ddl.ColumnDefinition;
import io.shardingsphere.core.parsing.antler.utils.TreeUtils;
import io.shardingsphere.core.parsing.parser.sql.SQLStatement;

public class RenameColumnVisitor implements PhraseVisitor {

    /** Visit rename column node.
     * @param ancestorNode ancestor node of ast
     * @param statement sql statement
     */
    @Override
    public void visit(final ParserRuleContext ancestorNode, final SQLStatement statement) {
        AlterTableStatement alterStatement = (AlterTableStatement) statement;
        
        ParserRuleContext modifyColumnCtx = TreeUtils.getFirstChildByRuleName(ancestorNode,
                "renameColumn");
        if (null == modifyColumnCtx) {
            return;
        }

        List<ParserRuleContext> columnNodes = TreeUtils.getAllDescendantByRuleName(modifyColumnCtx, "columnName");
        if (null == columnNodes || columnNodes.size() != 2) {
            return;
        }

        String oldName = columnNodes.get(0).getText();
        String newName = columnNodes.get(1).getText();
        ColumnDefinition oldDefinition = alterStatement.getUpdateColumns().remove(oldName);
        if (null != oldDefinition) {
            oldDefinition.setName(newName);
        } else {
            oldDefinition = new ColumnDefinition(newName, null, null, false);
        }

        alterStatement.getUpdateColumns().put(newName, oldDefinition);        
    }

}

/*
 * Copyright 2016-2018 shardingsphere.io.
 * <p>
 * Licensed 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.
 * </p>
 */

package io.shardingsphere.core.parsing.antler.phrase.visitor;

import java.util.List;

import org.antlr.v4.runtime.ParserRuleContext;

import io.shardingsphere.core.parsing.antler.sql.ddl.AlterTableStatement;
import io.shardingsphere.core.parsing.antler.sql.ddl.ColumnDefinition;
import io.shardingsphere.core.parsing.antler.utils.TreeUtils;
import io.shardingsphere.core.parsing.parser.sql.SQLStatement;

public class RenameColumnVisitor implements PhraseVisitor {

    /** Visit rename column node.
     * @param ancestorNode ancestor node of ast
     * @param statement sql statement
     */
    @Override
    public void visit(final ParserRuleContext ancestorNode, final SQLStatement statement) {
        AlterTableStatement alterStatement = (AlterTableStatement) statement;
        
        ParserRuleContext modifyColumnCtx = TreeUtils.getFirstChildByRuleName(ancestorNode,
                "renameColumn");
        if (null == modifyColumnCtx) {
            return;
        }

        List<ParserRuleContext> columnNodes = TreeUtils.getAllDescendantByRuleName(modifyColumnCtx, "columnName");
        if (null == columnNodes || columnNodes.size() != 2) {
            return;
        }

        String oldName = columnNodes.get(0).getText();
        String newName = columnNodes.get(1).getText();
        ColumnDefinition oldDefinition = alterStatement.getUpdateColumns().remove(oldName);
        if (null != oldDefinition) {
            oldDefinition.setName(newName);
        } else {
            oldDefinition = new ColumnDefinition(newName, null, null, false);
        }

        alterStatement.getUpdateColumns().put(oldName, oldDefinition);
    }

}

fix rename column bug