hazelcast-master/hazelcast-sql/src/main/java/com/hazelcast/jet/sql/impl/parse/SqlDropSnapshot.java
/*
 * Copyright 2023 Hazelcast Inc.
 *
 * Licensed under the Hazelcast Community License (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://hazelcast.com/hazelcast-community-license
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.hazelcast.jet.sql.impl.parse;

import com.hazelcast.internal.util.Preconditions;
import org.apache.calcite.sql.SqlDrop;
import org.apache.calcite.sql.SqlIdentifier;
import org.apache.calcite.sql.SqlKind;
import org.apache.calcite.sql.SqlNode;
import org.apache.calcite.sql.SqlOperator;
import org.apache.calcite.sql.SqlSpecialOperator;
import org.apache.calcite.sql.SqlWriter;
import org.apache.calcite.sql.parser.SqlParserPos;
import org.apache.calcite.sql.validate.SqlValidator;
import org.apache.calcite.sql.validate.SqlValidatorScope;
import org.apache.calcite.util.ImmutableNullableList;

import javax.annotation.Nonnull;
import java.util.List;

import static java.util.Objects.requireNonNull;

public class SqlDropSnapshot extends SqlDrop {

    private static final SqlSpecialOperator OPERATOR =
            new SqlSpecialOperator("DROP SNAPSHOT", SqlKind.OTHER_DDL);

    private final SqlIdentifier snapshotName;
    private final boolean ifExists;

    public SqlDropSnapshot(SqlIdentifier snapshotName, boolean ifExists, SqlParserPos pos) {
        super(OPERATOR, pos, true);

        this.snapshotName = requireNonNull(snapshotName, "Snapshot name must not be null");
        this.ifExists = ifExists;

        Preconditions.checkTrue(snapshotName.names.size() == 1, snapshotName.toString());
    }

    public String getSnapshotName() {
        return snapshotName.toString();
    }

    public boolean isIfExists() {
        return ifExists;
    }

    @Override @Nonnull
    public SqlOperator getOperator() {
        return OPERATOR;
    }

    @Override @Nonnull
    public List<SqlNode> getOperandList() {
        return ImmutableNullableList.of(snapshotName);
    }

    @Override
    public void unparse(SqlWriter writer, int leftPrec, int rightPrec) {
        writer.keyword("DROP SNAPSHOT");
        snapshotName.unparse(writer, leftPrec, rightPrec);
    }

    @Override
    public void validate(SqlValidator validator, SqlValidatorScope scope) {
    }
}
