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.core.metamodel.tabular.internal;
  
  import java.util.Optional;
  import java.util.function.BiPredicate;
  import java.util.function.Function;
  
  import org.jspecify.annotations.NonNull;
  import org.jspecify.annotations.Nullable;
  
  import org.apache.causeway.applib.services.filter.CollectionFilterService;
  import org.apache.causeway.applib.services.filter.CollectionFilterService.Tokens;
  import org.apache.causeway.applib.services.i18n.TranslationContext;
  import org.apache.causeway.applib.services.i18n.TranslationService;
  import org.apache.causeway.commons.internal.base._Casts;
  import org.apache.causeway.core.metamodel.spec.ObjectSpecification;
  import org.apache.causeway.core.metamodel.tabular.DataRow;
  
  record FilterUtils() {
  
      record FilterHandler(
          @NonNull Function<Object, Tokens> tokenizer,
          @NonNull BiPredicate<Tokens, String> tokenFilter,
          @NonNull String searchPromptPlaceholderText) {
  
          @NonNull BiPredicate<DataRow, String> getDataRowFilter() {
              return (dataRow, searchArg) ->
                  tokenFilter.test(dataRow.filterTokens().orElse(null), searchArg);
          }
      }
  
      static Optional<FilterHandler> createFilterHandler(final @Nullable ObjectSpecification elementType) {
          if(elementType==null) return Optional.empty();
  
          var mmc = elementType.getMetaModelContext();
          var collectionFilterServiceOpt = mmc.getServiceRegistry().select(CollectionFilterService.class).stream()
                  .filter(service->service.handles(elementType.getCorrespondingClass()))
                  .findFirst();
          if(!collectionFilterServiceOpt.isPresent()) {
              return Optional.empty();
          }
          var collectionFilterService = collectionFilterServiceOpt.get();
  
          var tokenizer =
                  collectionFilterService.tokenizer(elementType.getCorrespondingClass());
          if(tokenizer==null) {
              return Optional.empty();
          }
  
          var tokenFilter = collectionFilterService.tokenFilter(elementType.getCorrespondingClass());
          if(tokenFilter==null) {
              return Optional.empty();
          }
  
          var translationService = mmc.lookupService(TranslationService.class)
                  .orElseGet(TranslationService::identity);
          var translationContext = Optional.ofNullable(collectionFilterService.translationContext(elementType.getCorrespondingClass()))
                  .orElseGet(()->TranslationContext.named("Search"));
          var translatableString = collectionFilterService.searchPromptPlaceholderText(elementType.getCorrespondingClass());
  
          var searchPromptPlaceholderText = translatableString!=null
                  ? translatableString.translate(translationService, translationContext)
                  : "";
  
          return Optional.of(new FilterHandler(
                  _Casts.uncheckedCast(tokenizer),
                  tokenFilter,
                  searchPromptPlaceholderText));
      }
  
  }
  