/*
 * 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 com.dtstack.chunjun.ddl.convent.mysql.parse;

import org.apache.calcite.sql.SqlCall;
import org.apache.calcite.sql.SqlKind;
import org.apache.calcite.sql.SqlLiteral;
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.util.ImmutableNullableList;
import org.apache.calcite.util.NlsString;

import java.util.List;

import static java.util.Objects.requireNonNull;

/** Table options of a DDL, a key-value pair with both key and value as string literal. */
public class SqlServerOption extends SqlCall {
    /** Use this operator only if you don't have a better one. */
    protected static final SqlOperator OPERATOR =
            new SqlSpecialOperator("ServerOption", SqlKind.OTHER);

    protected final SqlNode key;
    protected final SqlNode value;

    public SqlServerOption(SqlParserPos pos, SqlNode key, SqlNode value) {
        super(pos);
        this.key = requireNonNull(key, "Option key is missing");
        this.value = requireNonNull(value, "Option value is missing");
    }

    public SqlNode getKey() {
        return key;
    }

    public SqlNode getValue() {
        return value;
    }

    public String getKeyString() {
        return ((NlsString) SqlLiteral.value(key)).getValue();
    }

    public String getValueString() {
        return ((NlsString) SqlLiteral.value(value)).getValue();
    }

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

    @Override
    public List<SqlNode> getOperandList() {
        return ImmutableNullableList.of(key, value);
    }

    @Override
    public void unparse(SqlWriter writer, int leftPrec, int rightPrec) {
        key.unparse(writer, leftPrec, rightPrec);
        writer.keyword("=");
        value.unparse(writer, leftPrec, rightPrec);
    }
}
