001/* -*- mode: Java; c-basic-offset: 2; indent-tabs-mode: nil; coding: utf-8-unix -*-
002 *
003 * Copyright © 2024 microBean™.
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
006 * the License. You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
011 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
012 * specific language governing permissions and limitations under the License.
013 */
014package org.microbean.bean;
015
016import java.lang.constant.ClassDesc;
017import java.lang.constant.Constable;
018import java.lang.constant.ConstantDesc;
019import java.lang.constant.DynamicConstantDesc;
020import java.lang.constant.MethodHandleDesc;
021
022import java.util.List;
023import java.util.Optional;
024
025import javax.lang.model.type.TypeMirror;
026
027import org.microbean.constant.Constables;
028
029import org.microbean.qualifier.NamedAttributeMap;
030
031import static java.lang.constant.ConstantDescs.BSM_INVOKE;
032import static java.lang.constant.ConstantDescs.CD_List;
033
034import static org.microbean.lang.ConstantDescs.CD_TypeMirror;
035
036public final record AttributedType(TypeMirror type, List<NamedAttributeMap<?>> attributes) implements Constable {
037
038  public AttributedType {
039    type = switch (type.getKind()) {
040    case ARRAY, BOOLEAN, BYTE, CHAR, DECLARED, DOUBLE, FLOAT, INT, LONG, SHORT -> type;
041    case ERROR, EXECUTABLE, INTERSECTION, MODULE, NONE, NULL, OTHER, PACKAGE, TYPEVAR, UNION, VOID, WILDCARD ->
042      throw new IllegalArgumentException("type: " + type);
043    };
044    attributes = List.copyOf(attributes);
045  }
046
047  public AttributedType(final TypeMirror type) {
048    this(type, List.of());
049  }
050
051  /**
052   * Returns an {@link Optional} containing a {@link ConstantDesc} describing this {@link AttributedType}, or an
053   * {@linkplain Optional#isEmpty() empty <code>Optional</code>} if it could not be described.
054   *
055   * @return an {@link Optional} containing a {@link ConstantDesc} describing this {@link AttributedType}, or an
056   * {@linkplain Optional#isEmpty() empty <code>Optional</code>} if it could not be describe; never {@code null}
057   */
058  @Override // Constable
059  public Optional<? extends ConstantDesc> describeConstable() {
060    return this.type() instanceof Constable t ? t.describeConstable() : Optional.<ConstantDesc>empty()
061      .flatMap(typeDesc -> Constables.describeConstable(this.attributes())
062               .map(attributesDesc -> DynamicConstantDesc.of(BSM_INVOKE,
063                                                             MethodHandleDesc.ofConstructor(ClassDesc.of(this.getClass().getName()),
064                                                                                            CD_TypeMirror,
065                                                                                            CD_List),
066                                                             typeDesc,
067                                                             attributesDesc)));
068  }
069
070}