better auto matching on anime and books when anilist is the source

docker/src/api/anime/anime.service.ts

@@ -276,7 +276,6 @@ export async function getAnimeInfoExtension(ext: Extension | null, id: string):
     if (!ext) return { error: "not found" };
 
     const extName = ext.constructor.name;
-
     const cached = await getCachedExtension(extName, id);
     if (cached) {
         try {
@@ -387,22 +386,41 @@ export async function searchEpisodesInExtension(ext: Extension | null, name: str
                         startDate: { year: 0, month: 0, day: 0 }
                     }
                 });
-
                 if (!matches || matches.length === 0) return [];
 
-                const res = matches[0];
+                const normalizedQuery = normalize(query);
+                const scored = matches.map(match => {
+                    const normalizedTitle = normalize(match.title);
+                    const score = similarity(normalizedQuery, normalizedTitle);
+
+                    let bonus = 0;
+                    if (normalizedTitle === normalizedQuery) {
+                        bonus = 0.5;
+                    } else if (normalizedTitle.toLowerCase().includes(normalizedQuery.toLowerCase())) {
+                        bonus = 0.5;
+                    }
+
+                    const finalScore = score + bonus;
+
+                    return {
+                        match,
+                        score: finalScore
+                    };
+                });
+
+                scored.sort((a, b) => b.score - a.score);
+                const bestMatches = scored.filter(s => s.score > 0.4);
+
+                if (bestMatches.length === 0) return [];
+                const res = bestMatches[0].match;
                 if (!res?.id) return [];
-
                 mediaId = res.id;
-
             } else {
                 mediaId = query;
             }
 
             const chapterList = await ext.findEpisodes(mediaId);
-
             if (!Array.isArray(chapterList)) return [];
-
             const result: Episode[] = chapterList.map(ep => ({
                 id: ep.id,
                 number: ep.number,
@@ -466,4 +484,47 @@ export async function getStreamData(extension: Extension, episode: string, id: s
 
     await setCache(cacheKey, streamData, CACHE_TTL_MS);
     return streamData;
+}
+
+function similarity(s1: string, s2: string): number {
+    const str1 = normalize(s1);
+    const str2 = normalize(s2);
+
+    const longer = str1.length > str2.length ? str1 : str2;
+    const shorter = str1.length > str2.length ? str2 : str1;
+
+    if (longer.length === 0) return 1.0;
+
+    const editDistance = levenshteinDistance(longer, shorter);
+    return (longer.length - editDistance) / longer.length;
+}
+
+function levenshteinDistance(s1: string, s2: string): number {
+    const costs: number[] = [];
+    for (let i = 0; i <= s1.length; i++) {
+        let lastValue = i;
+        for (let j = 0; j <= s2.length; j++) {
+            if (i === 0) {
+                costs[j] = j;
+            } else if (j > 0) {
+                let newValue = costs[j - 1];
+                if (s1.charAt(i - 1) !== s2.charAt(j - 1)) {
+                    newValue = Math.min(Math.min(newValue, lastValue), costs[j]) + 1;
+                }
+                costs[j - 1] = lastValue;
+                lastValue = newValue;
+            }
+        }
+        if (i > 0) costs[s2.length] = lastValue;
+    }
+    return costs[s2.length];
+}
+
+function normalize(str: string): string {
+    return str
+        .toLowerCase()
+        .replace(/&#39;/g, "'")     // decodificar entidades HTML
+        .replace(/[^\w\s]/g, ' ')   // convertir puntuación a espacios
+        .replace(/\s+/g, ' ')       // normalizar espacios
+        .trim();
 }