content: /*
   * Copyright © 2018-2025 Commonwealth Scientific and Industrial Research
   * Organisation (CSIRO) ABN 41 687 119 230.
   *
   * 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.
   */
  
  package au.csiro.pathling.fhirpath.operator;
  
  import static java.util.Objects.requireNonNull;
  
  import au.csiro.pathling.fhirpath.Numeric;
  import au.csiro.pathling.fhirpath.collection.Collection;
  import au.csiro.pathling.utilities.Preconditions;
  import jakarta.annotation.Nonnull;
  import jakarta.annotation.Nullable;
  
  /**
   * Represents a polarity operator in FHIRPath.
   *
   * @param negation True for '-' operator, false for '+' operator
   * @author Piotr Szul
   */
  public record PolarityOperator(boolean negation) implements UnaryOperator {
  
    @Override
    @Nonnull
    public Collection invoke(@Nullable final UnaryOperatorInput input) {
      requireNonNull(input);
      Preconditions.checkUserInput(input.input() instanceof Numeric,
          "Polarity operator can only be applied to numeric types");
      final Collection singularInput = input.input().asSingular(
          "Polarity operator (-) requires a singular operand."
      );
      return negation
             ? ((Numeric) singularInput).negate()
             : singularInput;
    }
  
    @Override
    @Nonnull
    public String getOperatorName() {
      return negation
             ? "-"
             : "+";
    }
  
    /**
     * Returns a new instance of {@link PolarityOperator} from the specified polarity symbol ('+' or
     * '-').
     *
     * @param symbol The polarity symbol to use
     * @return A new instance of {@link PolarityOperator}
     */
    @Nonnull
    public static PolarityOperator fromSymbol(@Nonnull final String symbol) {
      if (symbol.equals("+")) {
        return new PolarityOperator(false);
      } else if (symbol.equals("-")) {
        return new PolarityOperator(true);
      } else {
        throw new IllegalArgumentException("Invalid symbol: " + symbol);
      }
    }
  }
  