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.causeway.applib.services.placeholder;
  
  import java.util.Map;
  
  import org.jspecify.annotations.Nullable;
  
  import org.apache.causeway.commons.internal.base._StringInterpolation;
  
  import lombok.Getter;
  import org.jspecify.annotations.NonNull;
  import lombok.RequiredArgsConstructor;
  
  /**
   * Service that renders various {@link PlaceholderLiteral}s, as presented with the UI.
   *
   * @since 2.0 {@index}
   */
  public interface PlaceholderRenderService {
  
      @Getter
      @RequiredArgsConstructor
      public static enum PlaceholderLiteral {
          NULL_REPRESENTATION("none"),
          SUPPRESSED("suppressed"),
          HAS_MORE("has ${number} more");
          ;
          private final String literal;
      }
  
      /**
       * Textual representation of given {@link PlaceholderLiteral},
       * as used for eg. titles and choice drop-downs.
       */
      String asText(@NonNull PlaceholderLiteral placeholderLiteral, @Nullable Map<String, String> vars);
      default String asText(final @NonNull PlaceholderLiteral placeholderLiteral) {
          return asText(placeholderLiteral, null);
      }
  
      /**
       * HTML representation of given {@link PlaceholderLiteral},
       * as used for rendering with the UI (when appropriate).
       */
      String asHtml(@NonNull PlaceholderLiteral placeholderLiteral, @Nullable Map<String, String> vars);
      default String asHtml(final @NonNull PlaceholderLiteral placeholderLiteral) {
          return asHtml(placeholderLiteral, null);
      }
  
      static String interpolate(final String raw, final @Nullable Map<String, String> vars) {
          return vars!=null
                  ? new _StringInterpolation(vars).applyTo(raw)
                  : raw;
      }
  
      static PlaceholderRenderService fallback() {
          return new PlaceholderRenderService() {
              @Override public String asText(
                      final @NonNull PlaceholderLiteral placeholderLiteral,
                      final @Nullable Map<String, String> vars) {
                  return PlaceholderRenderService.interpolate(placeholderLiteral.getLiteral(), vars);
              }
  
              @Override public String asHtml(
                      final @NonNull PlaceholderLiteral placeholderLiteral,
                      final @Nullable Map<String, String> vars) {
                  return asText(placeholderLiteral, vars);
              }
          };
      }
  
  }
  