/*
 * 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.eigenbase.sql;

import java.util.List;

import org.eigenbase.reltype.*;
import org.eigenbase.sql.parser.*;
import org.eigenbase.sql.type.*;
import org.eigenbase.sql.validate.*;

import com.google.common.collect.ImmutableList;

import static org.eigenbase.util.Static.RESOURCE;

/**
 * Operator which aggregates sets of values into a result.
 */
public class SqlRankFunction extends SqlAggFunction {
  //~ Instance fields --------------------------------------------------------

  private final RelDataType type = null;

  //~ Constructors -----------------------------------------------------------

  public SqlRankFunction(String name) {
    super(
        name,
        SqlKind.OTHER_FUNCTION,
        ReturnTypes.INTEGER,
        null,
        OperandTypes.NILADIC,
        SqlFunctionCategory.NUMERIC);
  }

  //~ Methods ----------------------------------------------------------------

  @Override public boolean requiresOrder() {
    return true;
  }

  @Override public boolean allowsFraming() {
    return false;
  }

  public RelDataType getReturnType(RelDataTypeFactory typeFactory) {
    return type;
  }

  public List<RelDataType> getParameterTypes(RelDataTypeFactory typeFactory) {
    return ImmutableList.of(type);
  }

  public void validateCall(
      SqlCall call,
      SqlValidator validator,
      SqlValidatorScope scope,
      SqlValidatorScope operandScope) {
    final SqlParserPos pos = call.getParserPosition();
    throw SqlUtil.newContextException(pos,
        RESOURCE.functionUndefined(call.toString()));
  }
}

// End SqlRankFunction.java