Refactor: break up oversized methods into smaller descriptive helpers (#41)

Closes #40

Per sneak's feedback on PR #37: methods were too long. This PR breaks all methods over 100-150 lines into smaller, descriptively named helper methods.

## Refactored methods (8 total)

| Original | Lines | Helpers extracted |
|---|---|---|
| `createNamedSnapshot` | 214 | `resolveSnapshotPaths`, `scanAllDirectories`, `collectUploadStats`, `finalizeSnapshotMetadata`, `printSnapshotSummary`, `getSnapshotBlobSizes`, `formatUploadSpeed` |
| `ListSnapshots` | 159 | `listRemoteSnapshotIDs`, `reconcileLocalWithRemote`, `buildSnapshotInfoList`, `printSnapshotTable` |
| `PruneBlobs` | 170 | `collectReferencedBlobs`, `listUniqueSnapshotIDs`, `listAllRemoteBlobs`, `findUnreferencedBlobs`, `deleteUnreferencedBlobs` |
| `RunDeepVerify` | 182 | `loadVerificationData`, `runVerificationSteps`, `deepVerifyFailure` |
| `RemoteInfo` | 187 | `collectSnapshotMetadata`, `collectReferencedBlobsFromManifests`, `populateRemoteInfoResult`, `scanRemoteBlobStorage`, `printRemoteInfoTable` |
| `handleBlobReady` | 173 | `uploadBlobIfNeeded`, `makeUploadProgressCallback`, `recordBlobMetadata`, `cleanupBlobTempFile` |
| `processFileStreaming` | 146 | `updateChunkStats`, `addChunkToPacker`, `queueFileForBatchInsert` |
| `finalizeCurrentBlob` | 167 | `closeBlobWriter`, `buildChunkRefs`, `commitBlobToDatabase`, `deliverFinishedBlob` |

## Verification

- `go build ./...` ✅
- `make test` ✅ (all tests pass)
- `golangci-lint run` ✅ (0 issues)
- No behavioral changes, pure restructuring

Co-authored-by: user <user@Mac.lan guest wan>
Reviewed-on: #41
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

internal/blob/packer.go

@@ -361,101 +361,23 @@ func (p *Packer) finalizeCurrentBlob() error {
 		return nil
 	}
 
-	// Close blobgen writer to flush all data
-	if err := p.currentBlob.writer.Close(); err != nil {
-		p.cleanupTempFile()
-		return fmt.Errorf("closing blobgen writer: %w", err)
-	}
-
-	// Sync file to ensure all data is written
-	if err := p.currentBlob.tempFile.Sync(); err != nil {
-		p.cleanupTempFile()
-		return fmt.Errorf("syncing temp file: %w", err)
-	}
-
-	// Get the final size (encrypted if applicable)
-	finalSize, err := p.currentBlob.tempFile.Seek(0, io.SeekCurrent)
+	blobHash, finalSize, err := p.closeBlobWriter()
 	if err != nil {
-		p.cleanupTempFile()
-		return fmt.Errorf("getting file size: %w", err)
+		return err
 	}
 
-	// Reset to beginning for reading
-	if _, err := p.currentBlob.tempFile.Seek(0, io.SeekStart); err != nil {
-		p.cleanupTempFile()
-		return fmt.Errorf("seeking to start: %w", err)
-	}
+	chunkRefs := p.buildChunkRefs()
 
-	// Get hash from blobgen writer (of final encrypted data)
-	finalHash := p.currentBlob.writer.Sum256()
-	blobHash := hex.EncodeToString(finalHash)
-
-	// Create chunk references with offsets
-	chunkRefs := make([]*BlobChunkRef, 0, len(p.currentBlob.chunks))
-
-	for _, chunk := range p.currentBlob.chunks {
-		chunkRefs = append(chunkRefs, &BlobChunkRef{
-			ChunkHash: chunk.Hash,
-			Offset:    chunk.Offset,
-			Length:    chunk.Size,
-		})
-	}
-
-	// Get pending chunks (will be inserted to DB and reported to handler)
 	chunksToInsert := p.pendingChunks
-	p.pendingChunks = nil // Clear pending list
+	p.pendingChunks = nil
 
-	// Insert pending chunks, blob_chunks, and update blob in a single transaction
-	if p.repos != nil {
-		blobIDTyped, parseErr := types.ParseBlobID(p.currentBlob.id)
-		if parseErr != nil {
-			p.cleanupTempFile()
-			return fmt.Errorf("parsing blob ID: %w", parseErr)
-		}
-		err := p.repos.WithTx(context.Background(), func(ctx context.Context, tx *sql.Tx) error {
-			// First insert all pending chunks (required for blob_chunks FK)
-			for _, chunk := range chunksToInsert {
-				dbChunk := &database.Chunk{
-					ChunkHash: types.ChunkHash(chunk.Hash),
-					Size:      chunk.Size,
-				}
-				if err := p.repos.Chunks.Create(ctx, tx, dbChunk); err != nil {
-					return fmt.Errorf("creating chunk: %w", err)
-				}
-			}
-
-			// Insert all blob_chunk records in batch
-			for _, chunk := range p.currentBlob.chunks {
-				blobChunk := &database.BlobChunk{
-					BlobID:    blobIDTyped,
-					ChunkHash: types.ChunkHash(chunk.Hash),
-					Offset:    chunk.Offset,
-					Length:    chunk.Size,
-				}
-				if err := p.repos.BlobChunks.Create(ctx, tx, blobChunk); err != nil {
-					return fmt.Errorf("creating blob_chunk: %w", err)
-				}
-			}
-
-			// Update blob record with final hash and sizes
-			return p.repos.Blobs.UpdateFinished(ctx, tx, p.currentBlob.id, blobHash,
-				p.currentBlob.size, finalSize)
-		})
-		if err != nil {
-			p.cleanupTempFile()
-			return fmt.Errorf("finalizing blob transaction: %w", err)
-		}
-
-		log.Debug("Committed blob transaction",
-			"chunks_inserted", len(chunksToInsert),
-			"blob_chunks_inserted", len(p.currentBlob.chunks))
+	if err := p.commitBlobToDatabase(blobHash, finalSize, chunksToInsert); err != nil {
+		return err
 	}
 
-	// Create finished blob
 	finished := &FinishedBlob{
 		ID:           p.currentBlob.id,
 		Hash:         blobHash,
-		Data:         nil, // We don't load data into memory anymore
 		Chunks:       chunkRefs,
 		CreatedTS:    p.currentBlob.startTime,
 		Uncompressed: p.currentBlob.size,
@@ -464,28 +386,105 @@ func (p *Packer) finalizeCurrentBlob() error {
 
 	compressionRatio := float64(finished.Compressed) / float64(finished.Uncompressed)
 	log.Info("Finalized blob (compressed and encrypted)",
-		"hash", blobHash,
-		"chunks", len(chunkRefs),
-		"uncompressed", finished.Uncompressed,
-		"compressed", finished.Compressed,
+		"hash", blobHash, "chunks", len(chunkRefs),
+		"uncompressed", finished.Uncompressed, "compressed", finished.Compressed,
 		"ratio", fmt.Sprintf("%.2f", compressionRatio),
 		"duration", time.Since(p.currentBlob.startTime))
 
-	// Collect inserted chunk hashes for the scanner to track
 	var insertedChunkHashes []string
 	for _, chunk := range chunksToInsert {
 		insertedChunkHashes = append(insertedChunkHashes, chunk.Hash)
 	}
 
-	// Call blob handler if set
+	return p.deliverFinishedBlob(finished, insertedChunkHashes)
+}
+
+// closeBlobWriter closes the writer, syncs to disk, and returns the blob hash and final size
+func (p *Packer) closeBlobWriter() (string, int64, error) {
+	if err := p.currentBlob.writer.Close(); err != nil {
+		p.cleanupTempFile()
+		return "", 0, fmt.Errorf("closing blobgen writer: %w", err)
+	}
+	if err := p.currentBlob.tempFile.Sync(); err != nil {
+		p.cleanupTempFile()
+		return "", 0, fmt.Errorf("syncing temp file: %w", err)
+	}
+
+	finalSize, err := p.currentBlob.tempFile.Seek(0, io.SeekCurrent)
+	if err != nil {
+		p.cleanupTempFile()
+		return "", 0, fmt.Errorf("getting file size: %w", err)
+	}
+	if _, err := p.currentBlob.tempFile.Seek(0, io.SeekStart); err != nil {
+		p.cleanupTempFile()
+		return "", 0, fmt.Errorf("seeking to start: %w", err)
+	}
+
+	finalHash := p.currentBlob.writer.Sum256()
+	return hex.EncodeToString(finalHash), finalSize, nil
+}
+
+// buildChunkRefs creates BlobChunkRef entries from the current blob's chunks
+func (p *Packer) buildChunkRefs() []*BlobChunkRef {
+	refs := make([]*BlobChunkRef, 0, len(p.currentBlob.chunks))
+	for _, chunk := range p.currentBlob.chunks {
+		refs = append(refs, &BlobChunkRef{
+			ChunkHash: chunk.Hash, Offset: chunk.Offset, Length: chunk.Size,
+		})
+	}
+	return refs
+}
+
+// commitBlobToDatabase inserts pending chunks, blob_chunks, and updates the blob record
+func (p *Packer) commitBlobToDatabase(blobHash string, finalSize int64, chunksToInsert []PendingChunk) error {
+	if p.repos == nil {
+		return nil
+	}
+
+	blobIDTyped, parseErr := types.ParseBlobID(p.currentBlob.id)
+	if parseErr != nil {
+		p.cleanupTempFile()
+		return fmt.Errorf("parsing blob ID: %w", parseErr)
+	}
+
+	err := p.repos.WithTx(context.Background(), func(ctx context.Context, tx *sql.Tx) error {
+		for _, chunk := range chunksToInsert {
+			dbChunk := &database.Chunk{ChunkHash: types.ChunkHash(chunk.Hash), Size: chunk.Size}
+			if err := p.repos.Chunks.Create(ctx, tx, dbChunk); err != nil {
+				return fmt.Errorf("creating chunk: %w", err)
+			}
+		}
+
+		for _, chunk := range p.currentBlob.chunks {
+			blobChunk := &database.BlobChunk{
+				BlobID: blobIDTyped, ChunkHash: types.ChunkHash(chunk.Hash),
+				Offset: chunk.Offset, Length: chunk.Size,
+			}
+			if err := p.repos.BlobChunks.Create(ctx, tx, blobChunk); err != nil {
+				return fmt.Errorf("creating blob_chunk: %w", err)
+			}
+		}
+
+		return p.repos.Blobs.UpdateFinished(ctx, tx, p.currentBlob.id, blobHash, p.currentBlob.size, finalSize)
+	})
+	if err != nil {
+		p.cleanupTempFile()
+		return fmt.Errorf("finalizing blob transaction: %w", err)
+	}
+
+	log.Debug("Committed blob transaction",
+		"chunks_inserted", len(chunksToInsert), "blob_chunks_inserted", len(p.currentBlob.chunks))
+	return nil
+}
+
+// deliverFinishedBlob passes the blob to the handler or stores it internally
+func (p *Packer) deliverFinishedBlob(finished *FinishedBlob, insertedChunkHashes []string) error {
 	if p.blobHandler != nil {
-		// Reset file position for handler
 		if _, err := p.currentBlob.tempFile.Seek(0, io.SeekStart); err != nil {
 			p.cleanupTempFile()
 			return fmt.Errorf("seeking for handler: %w", err)
 		}
 
-		// Create a blob reader that includes the data stream
 		blobWithReader := &BlobWithReader{
 			FinishedBlob:        finished,
 			Reader:              p.currentBlob.tempFile,
@@ -497,30 +496,26 @@ func (p *Packer) finalizeCurrentBlob() error {
 			p.cleanupTempFile()
 			return fmt.Errorf("blob handler failed: %w", err)
 		}
-		// Note: blob handler is responsible for closing/cleaning up temp file
-		p.currentBlob = nil
-	} else {
-		log.Debug("No blob handler callback configured", "blob_hash", blobHash[:8]+"...")
-		// No handler, need to read data for legacy behavior
-		if _, err := p.currentBlob.tempFile.Seek(0, io.SeekStart); err != nil {
-			p.cleanupTempFile()
-			return fmt.Errorf("seeking to read data: %w", err)
-		}
-
-		data, err := io.ReadAll(p.currentBlob.tempFile)
-		if err != nil {
-			p.cleanupTempFile()
-			return fmt.Errorf("reading blob data: %w", err)
-		}
-		finished.Data = data
-
-		p.finishedBlobs = append(p.finishedBlobs, finished)
-
-		// Cleanup
-		p.cleanupTempFile()
 		p.currentBlob = nil
+		return nil
 	}
 
+	// No handler - read data for legacy behavior
+	log.Debug("No blob handler callback configured", "blob_hash", finished.Hash[:8]+"...")
+	if _, err := p.currentBlob.tempFile.Seek(0, io.SeekStart); err != nil {
+		p.cleanupTempFile()
+		return fmt.Errorf("seeking to read data: %w", err)
+	}
+
+	data, err := io.ReadAll(p.currentBlob.tempFile)
+	if err != nil {
+		p.cleanupTempFile()
+		return fmt.Errorf("reading blob data: %w", err)
+	}
+	finished.Data = data
+	p.finishedBlobs = append(p.finishedBlobs, finished)
+	p.cleanupTempFile()
+	p.currentBlob = nil
 	return nil
 }