/*
 * 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.antlr.extractor.statement.handler.dialect.sqlserver;

import org.antlr.v4.runtime.ParserRuleContext;

import com.google.common.base.Optional;

import io.shardingsphere.core.parsing.antlr.extractor.statement.handler.ASTExtractHandler;
import io.shardingsphere.core.parsing.antlr.extractor.statement.handler.RuleName;
import io.shardingsphere.core.parsing.antlr.extractor.statement.handler.result.ExtractResult;
import io.shardingsphere.core.parsing.antlr.extractor.statement.handler.result.SQLTokenExtractResult;
import io.shardingsphere.core.parsing.antlr.extractor.statement.util.ASTUtils;
import io.shardingsphere.core.parsing.parser.token.IndexToken;
import io.shardingsphere.core.util.SQLUtil;

/**
 * SQLServer Add index extract handler for SQLServer.
 * 
 * @author duhongjun
 */
public final class SQLServerAddIndexExtractHandler implements ASTExtractHandler {

    @Override
    public ExtractResult extract(final ParserRuleContext ancestorNode) {
        Optional<ParserRuleContext> indexDefOptionNode = ASTUtils.findFirstChildNode(ancestorNode, RuleName.ADD_COLUMN);
        if (!indexDefOptionNode.isPresent()) {
            return null;
        }
        Optional<ParserRuleContext> indexNameNode = ASTUtils.findFirstChildNode(indexDefOptionNode.get(), RuleName.INDEX_NAME);
        if (!indexNameNode.isPresent()) {
            return null;
        }
        SQLTokenExtractResult extractResult = new SQLTokenExtractResult();
        extractResult.getSqlTokens().add(
                new IndexToken(indexNameNode.get().getStop().getStartIndex(), SQLUtil.getNameWithoutSchema(indexNameNode.get().getText()), null));
        return extractResult;
    }
}

@@ -1520,16 +1520,20 @@
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@@ -1550,16 +1550,25 @@
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@@ -1564,32 +1564,33 @@
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@@ -1801,36 +1801,49 @@
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@@ -2027,20 +2027,33 @@
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@@ -2086,24 +2086,17 @@
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@@ -2132,24 +2132,17 @@
         
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@@ -2321,17 +2321,27 @@
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@@ -2344,16 +2344,27 @@
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use optional for checkstyle