/*
    * 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
    *
    *      https://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.commons.text.similarity;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link EditDistanceFrom}.
   */
  class StringMetricFromTest {
  
      @Test
      void testEquivalence() {
          final EditDistance<Integer> metric = LevenshteinDistance.getDefaultInstance();
          final String left = "Apache";
          final String right = "a patchy";
          final Integer distance = 4;
          final EditDistanceFrom<Integer> metricFrom = new EditDistanceFrom<>(metric, left);
  
          assertEquals(distance, metricFrom.apply(right));
          assertEquals(metric.apply(left, right), metricFrom.apply(right));
      }
  
      @Test
      void testJavadocExample() {
          final EditDistance<Integer> metric = LevenshteinDistance.getDefaultInstance();
          final String target = "Apache";
          final EditDistanceFrom<Integer> metricFrom = new EditDistanceFrom<>(metric, target);
          String mostSimilar = null;
          Integer shortestDistance = null;
  
          for (final String test : new String[] { "Appaloosa", "a patchy", "apple" }) {
              final Integer distance = metricFrom.apply(test);
              if (shortestDistance == null || distance < shortestDistance) {
                  shortestDistance = distance;
                  mostSimilar = test;
              }
          }
          assertEquals("a patchy", mostSimilar);
          assertEquals(4, shortestDistance);
      }
  
      @Test
      void testMissingMetric() {
          assertThrows(IllegalArgumentException.class, () -> new EditDistanceFrom<Number>(null, "no go"));
      }
  
  }