content: /*
   * 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.apache.calcite.sql.fun;
  
  import org.apache.calcite.rel.type.RelDataType;
  import org.apache.calcite.sql.SqlBinaryOperator;
  import org.apache.calcite.sql.SqlCall;
  import org.apache.calcite.sql.SqlCallBinding;
  import org.apache.calcite.sql.SqlKind;
  import org.apache.calcite.sql.SqlOperandCountRange;
  import org.apache.calcite.sql.SqlUtil;
  import org.apache.calcite.sql.SqlWriter;
  import org.apache.calcite.sql.type.InferTypes;
  import org.apache.calcite.sql.type.OperandTypes;
  import org.apache.calcite.sql.type.ReturnTypes;
  import org.apache.calcite.sql.type.SqlOperandCountRanges;
  import org.apache.calcite.sql.type.SqlSingleOperandTypeChecker;
  import org.apache.calcite.sql.type.SqlTypeUtil;
  
  import com.google.common.collect.ImmutableList;
  
  /**
   * SqlOverlapsOperator represents the SQL:1999 standard {@code OVERLAPS}
   * function. Determines whether two anchored time intervals overlap.
   */
  public class SqlOverlapsOperator extends SqlBinaryOperator {
    //~ Constructors -----------------------------------------------------------
  
    SqlOverlapsOperator(SqlKind kind) {
      super(kind.sql, kind, 30, true, ReturnTypes.BOOLEAN_NULLABLE,
          InferTypes.FIRST_KNOWN,
          OperandTypes.sequence("'<PERIOD> " + kind.sql + " <PERIOD>'",
              OperandTypes.PERIOD, OperandTypes.PERIOD));
    }
  
    //~ Methods ----------------------------------------------------------------
  
    @Override public void unparse(SqlWriter writer, SqlCall call, int leftPrec,
        int rightPrec) {
      final SqlWriter.Frame frame =
          writer.startList(SqlWriter.FrameTypeEnum.SIMPLE);
      arg(writer, call, leftPrec, rightPrec, 0);
      writer.sep(getName());
      arg(writer, call, leftPrec, rightPrec, 1);
      writer.endList(frame);
    }
  
    void arg(SqlWriter writer, SqlCall call, int leftPrec, int rightPrec, int i) {
      if (SqlUtil.isCallTo(call.operand(i), SqlStdOperatorTable.ROW)) {
        SqlCall row = call.operand(i);
        writer.keyword("PERIOD");
        writer.sep("(", true);
        row.operand(0).unparse(writer, leftPrec, rightPrec);
        writer.sep(",", true);
        row.operand(1).unparse(writer, leftPrec, rightPrec);
        writer.sep(")", true);
      } else {
        call.operand(i).unparse(writer, leftPrec, rightPrec);
      }
    }
  
    @Override public SqlOperandCountRange getOperandCountRange() {
      return SqlOperandCountRanges.of(2);
    }
  
    @Override public String getAllowedSignatures(String opName) {
      final String d = "DATETIME";
      final String i = "INTERVAL";
      String[] typeNames = {
          d, d,
          d, i,
          i, d,
          i, i
      };
  
      StringBuilder ret = new StringBuilder();
      for (int y = 0; y < typeNames.length; y += 2) {
        if (y > 0) {
          ret.append(NL);
        }
        ret.append(
            SqlUtil.getAliasedSignature(this, opName,
                ImmutableList.of(d, typeNames[y], d, typeNames[y + 1])));
      }
      return ret.toString();
    }
  
    @Override public boolean checkOperandTypes(SqlCallBinding callBinding,
        boolean throwOnFailure) {
      if (!OperandTypes.PERIOD.checkSingleOperandType(callBinding,
          callBinding.operand(0), 0, throwOnFailure)) {
        return false;
      }
      final SqlSingleOperandTypeChecker rightChecker;
      switch (kind) {
      case CONTAINS:
        rightChecker = OperandTypes.PERIOD_OR_DATETIME;
        break;
      default:
        rightChecker = OperandTypes.PERIOD;
        break;
      }
      if (!rightChecker.checkSingleOperandType(callBinding,
          callBinding.operand(1), 0, throwOnFailure)) {
        return false;
      }
      final RelDataType t0 = callBinding.getOperandType(0);
      final RelDataType t1 = callBinding.getOperandType(1);
      if (!SqlTypeUtil.isDatetime(t1)) {
        final RelDataType t00 = t0.getFieldList().get(0).getType();
        final RelDataType t10 = t1.getFieldList().get(0).getType();
        if (!SqlTypeUtil.sameNamedType(t00, t10)) {
          if (throwOnFailure) {
            throw callBinding.newValidationSignatureError();
          }
          return false;
        }
      }
      return true;
    }
  }
  