NCBACK-34 add logic to find similar image in db

2026-01-13 22:40:52 +07:00
parent 344ec075d4
commit 8ac73ff045
18 changed files with 394 additions and 188 deletions
@@ -0,0 +1,62 @@
+package ru.soune.nocopy.service;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import ru.soune.nocopy.dto.file.SimilarFileResponse;
+import ru.soune.nocopy.repository.ImageHashRepository;
+import ru.soune.nocopy.repository.ImageSimilarityRepository;
+import ru.soune.nocopy.repository.SimilarImageProjection;
+
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class FileSimilarityService {
+
+    private final ImageSimilarityRepository repository;
+    private final ImageHashRepository hashRepository;
+
+    public List<SimilarFileResponse> findSimilarFiles(String fileId) {
+        var imageHashEntity = hashRepository.findById(fileId)
+                .orElseThrow(() -> new RuntimeException("Hash not found"));
+
+        Integer hash64Hi = imageHashEntity.getHash64Hi();
+        Integer hash64Lo = imageHashEntity.getHash64Lo();
+
+        List<SimilarImageProjection> candidates =
+                repository.findCandidates(fileId);
+
+        return candidates.stream()
+                .map(c -> {
+                    Integer cHi = c.getHash64Hi();
+                    Integer cLo = c.getHash64Lo();
+
+                    int hamming = hamming64(hash64Hi, hash64Lo, cHi, cLo);
+
+                    String level;
+                    if (hamming <= 5) {
+                        level = "DUPLICATE";
+                    } else if (hamming <= 12) {
+                        level = "SIMILAR";
+                    } else {
+                        level = "DIFFERENT";
+                    }
+
+                    return SimilarFileResponse.builder()
+                            .fileId(c.getSimilarFileId())
+                            .originalFileName(c.getOriginalFileName())
+                            .fileSize(c.getFileSize())
+                            .hammingDistance(hamming)
+                            .similarityLevel(level)
+                            .build();
+                })
+                .sorted((a, b) ->
+                        Integer.compare(a.getHammingDistance(), b.getHammingDistance()))
+                .toList();
+    }
+
+    private int hamming64(int aHi, int aLo, int bHi, int bLo) {
+        return Integer.bitCount(aHi ^ bHi)
+                + Integer.bitCount(aLo ^ bLo);
+    }
+}