feat(igdb): rank game search by popularity and help with typos

IGDB lists every e-Reader card as a game, and its own order
puts obscure entries first. Core now drops e-Reader-only
games, asks for 50 hits and sorts exact name first, then by
rating count. When a search finds fewer than 3 games, Core
searches again without doubled letters and with single
words, and adds those hits by Levenshtein distance after
IGDB's own hits.

Also fixes a flaky test that read the time to beat before
the background refresh wrote it.

src/test/java/core_service/modules/igdb_adapter/service/IgdbApiServiceTest.java

@@ -194,7 +194,8 @@ class IgdbApiServiceTest extends AbstractUnitTest {
         expectToken();
         igdb.expect(requestTo(containsString("/games")))
                 .andExpect(content().string(allOf(containsString("search \"zelda\";"), containsString("version_parent = null"),
-                        containsString("game_type = (0,4,7,8,9,10,11)"), containsString("limit 20"))))
+                        containsString("game_type = (0,4,7,8,9,10,11)"), containsString("total_rating_count"),
+                        containsString("limit 50"))))
                 .andRespond(withSuccess(ZELDA, MediaType.APPLICATION_JSON));
 
         List<IgdbApiService.Game> games = service.searchGames(" zelda ").orElseThrow();
@@ -206,6 +207,32 @@ class IgdbApiServiceTest extends AbstractUnitTest {
                         "https://images.igdb.com/igdb/image/upload/t_screenshot_med/ar1.jpg", List.of("PS5", "PC"), 1245620L));
     }
 
+    @Test
+    void searchGames_PutsTheExactNameFirstThenTheGamesWithMoreRatings() {
+        expectToken();
+        igdb.expect(requestTo(containsString("/games")))
+                .andRespond(withSuccess("[{\"id\": 1, \"name\": \"Super Super Super Super\"},"
+                        + " {\"id\": 2, \"name\": \"Super Mario Galaxy 2\", \"total_rating_count\": 900},"
+                        + " {\"id\": 3, \"name\": \"Super Mario Bros.\", \"total_rating_count\": 1500},"
+                        + " {\"id\": 4, \"name\": \"Super Mario\", \"total_rating_count\": 5}]", MediaType.APPLICATION_JSON));
+
+        assertThat(service.searchGames("super mario").orElseThrow()).extracting(IgdbApiService.Game::igdbId)
+                .containsExactly(4L, 3L, 2L, 1L);
+    }
+
+    @Test
+    void searchGames_LeavesOutGamesOnlyOnTheEReader() {
+        expectToken();
+        igdb.expect(requestTo(containsString("/games")))
+                .andRespond(withSuccess("[{\"id\": 1, \"name\": \"Super Mario Advance 4: Super Mario Bros. 3-e - Para Beetle Challenge\","
+                        + " \"platforms\": [{\"id\": 510, \"name\": \"e-Reader / Card-e Reader\"}]},"
+                        + " {\"id\": 2, \"name\": \"Super Mario Advance 4\", \"platforms\": [{\"id\": 24, \"name\": \"Game Boy Advance\", \"abbreviation\": \"GBA\"},"
+                        + " {\"id\": 510, \"name\": \"e-Reader / Card-e Reader\"}]}]", MediaType.APPLICATION_JSON));
+
+        assertThat(service.searchGames("super mario").orElseThrow()).extracting(IgdbApiService.Game::igdbId)
+                .containsExactly(2L);
+    }
+
     @Test
     void searchGames_OnlyACover_UsesTheCover() {
         expectToken();

src/test/java/core_service/modules/library/api/ManualGameControllerTest.java

@@ -305,6 +305,7 @@ class ManualGameControllerTest extends AbstractIntegrationTest {
     @Test
     void gameAddedByHand_ShowsUpInTheLibraryAndItsDetail() throws Exception {
         add(119388, "Switch");
+        timeToBeatStored(-119388L);
 
         mockMvc.perform(get("/api/library/games").param("q", "zelda"))
                 .andExpect(status().isOk())

src/test/java/core_service/modules/library/service/FuzzySearchTest.java

@@ -0,0 +1,43 @@
+package core_service.modules.library.service;
+
+import core_service.shared.test.AbstractUnitTest;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class FuzzySearchTest extends AbstractUnitTest {
+
+    @Test
+    void withoutDoubledLetters_KeepsOneLetterOfEachRun() {
+        assertThat(FuzzySearch.withoutDoubledLetters("Superr Marioo")).contains("Super Mario");
+    }
+
+    @Test
+    void withoutDoubledLetters_NothingDoubled_IsEmpty() {
+        assertThat(FuzzySearch.withoutDoubledLetters("Zelda Breath")).isEmpty();
+    }
+
+    @Test
+    void words_SkipShortWordsAndStopAtTwo() {
+        assertThat(FuzzySearch.words("of the Legend Zelda Breath")).containsExactly("Legend", "Zelda");
+    }
+
+    @Test
+    void words_OneWord_HasNone() {
+        assertThat(FuzzySearch.words("Zelda")).isEmpty();
+    }
+
+    @Test
+    void distance_ComparesWithTheStartOfTheNameIgnoringCase() {
+        assertThat(FuzzySearch.distance("superr mario", "Super Mario Bros. 3")).isEqualTo(1);
+        assertThat(FuzzySearch.distance("mass efect", "Mass Effect")).isEqualTo(1);
+        assertThat(FuzzySearch.distance("mass efect", "Mass Destruction")).isGreaterThan(3);
+    }
+
+    @Test
+    void levenshtein_CountsInsertsDeletesAndChanges() {
+        assertThat(FuzzySearch.levenshtein("kitten", "sitting")).isEqualTo(3);
+        assertThat(FuzzySearch.levenshtein("", "abc")).isEqualTo(3);
+        assertThat(FuzzySearch.levenshtein("same", "same")).isZero();
+    }
+}

src/test/java/core_service/modules/library/service/ManualGameServiceTest.java

@@ -17,6 +17,10 @@ import java.util.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 class ManualGameServiceTest extends AbstractUnitTest {
@@ -76,4 +80,93 @@ class ManualGameServiceTest extends AbstractUnitTest {
 
         assertThat(result).isEqualTo(new ManualGameService.AddResult.Added(-119388L));
     }
+
+    private static IgdbApiService.Game game(long igdbId, String name) {
+        return new IgdbApiService.Game(igdbId, name, 2000, null, List.of("Switch"), null);
+    }
+
+    @Test
+    void search_TypoWithADoubledLetter_FindsTheGameWithoutIt() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames("Superr Mario")).thenReturn(Optional.of(List.of()));
+        when(igdbApiService.searchGames("Super Mario")).thenReturn(Optional.of(List.of(
+                game(3, "Super Mario Bros. 3"), game(1, "Super Mario Bros."), game(2, "Super Mario 64"))));
+
+        List<String> names = service.search(USER_ID, "Superr Mario").orElseThrow().results().stream()
+                .map(hit -> hit.name()).toList();
+
+        assertThat(names).containsExactly("Super Mario Bros. 3", "Super Mario Bros.", "Super Mario 64");
+    }
+
+    @Test
+    void search_TypoInOneWord_SearchesTheWordsAloneAndPutsTheClosestNameFirst() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames(anyString())).thenReturn(Optional.of(List.of()));
+        when(igdbApiService.searchGames("Mass")).thenReturn(Optional.of(List.of(
+                game(1, "Mass Destruction"), game(2, "Mass Effect"))));
+        when(igdbApiService.searchGames("Efect")).thenReturn(Optional.empty());
+
+        List<String> names = service.search(USER_ID, "Mass Efect").orElseThrow().results().stream()
+                .map(hit -> hit.name()).toList();
+
+        assertThat(names).containsExactly("Mass Effect", "Mass Destruction");
+    }
+
+    @Test
+    void search_EnoughHits_AsksIgdbOnce() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames("zelda")).thenReturn(Optional.of(List.of(
+                game(1, "Zelda A"), game(2, "Zelda B"), game(3, "Zelda C"))));
+
+        assertThat(service.search(USER_ID, "zelda").orElseThrow().results()).hasSize(3);
+        verify(igdbApiService, times(1)).searchGames(anyString());
+    }
+
+    @Test
+    void search_TheGameIgdbFoundStaysBeforeTheTypoHits() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames("Breath of the Wild")).thenReturn(Optional.of(List.of(
+                game(1, "The Legend of Zelda: Breath of the Wild"))));
+        when(igdbApiService.searchGames("Breath")).thenReturn(Optional.of(List.of(
+                game(2, "Breath of Fire"), game(3, "Breath of Fire II"))));
+
+        List<String> names = service.search(USER_ID, "Breath of the Wild").orElseThrow().results().stream()
+                .map(hit -> hit.name()).toList();
+
+        assertThat(names).startsWith("The Legend of Zelda: Breath of the Wild");
+    }
+
+    @Test
+    void search_FewHits_KeepTheOrderOfTheSearch() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames(anyString())).thenReturn(Optional.of(List.of()));
+        when(igdbApiService.searchGames("zelda wild")).thenReturn(Optional.of(List.of(
+                game(1, "The Legend of Zelda: Breath of the Wild"), game(2, "Zelda: The Wand of Gamelon"))));
+
+        List<String> names = service.search(USER_ID, "zelda wild").orElseThrow().results().stream()
+                .map(hit -> hit.name()).toList();
+
+        assertThat(names).containsExactly("The Legend of Zelda: Breath of the Wild", "Zelda: The Wand of Gamelon");
+    }
+
+    @Test
+    void search_IgdbFailed_IsEmptyEvenWithoutAFallback() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames(anyString())).thenReturn(Optional.empty());
+
+        assertThat(service.search(USER_ID, "Superr Mario")).isEmpty();
+    }
+
+    @Test
+    void search_SomeHits_TriesNoDoubledLetterVariantAndAtMostTwoWords() {
+        when(igdbApiService.isEnabled()).thenReturn(true);
+        when(igdbApiService.searchGames(anyString())).thenReturn(Optional.of(List.of()));
+        when(igdbApiService.searchGames("Hollow Knight Silksong")).thenReturn(Optional.of(List.of(game(1, "Hollow Knight"))));
+
+        service.search(USER_ID, "Hollow Knight Silksong");
+
+        verify(igdbApiService, never()).searchGames("Holow Knight Silksong");
+        verify(igdbApiService, never()).searchGames("Silksong");
+        verify(igdbApiService, times(3)).searchGames(anyString());
+    }
 }