feat: add progress bar to restore operation

Add an interactive progress bar (using schollz/progressbar) to the
file restore loop, matching the existing pattern in verify. Shows
bytes restored with ETA when output is a terminal, falls back to
structured log progress every 100 files otherwise.

Fixes #20

internal/vaultik/restore.go

@@ -111,6 +111,30 @@ func (v *Vaultik) Restore(opts *RestoreOptions) error {
 	result := &RestoreResult{}
 	blobCache := make(map[string][]byte) // Cache downloaded and decrypted blobs
 
+	// Calculate total bytes for progress bar
+	var totalBytesExpected int64
+	for _, file := range files {
+		totalBytesExpected += file.Size
+	}
+
+	// Create progress bar if output is a terminal
+	var bar *progressbar.ProgressBar
+	if isTerminal() {
+		bar = progressbar.NewOptions64(
+			totalBytesExpected,
+			progressbar.OptionSetDescription("Restoring"),
+			progressbar.OptionSetWriter(os.Stderr),
+			progressbar.OptionShowBytes(true),
+			progressbar.OptionShowCount(),
+			progressbar.OptionSetWidth(40),
+			progressbar.OptionThrottle(100*time.Millisecond),
+			progressbar.OptionOnCompletion(func() {
+				fmt.Fprint(os.Stderr, "\n")
+			}),
+			progressbar.OptionSetRenderBlankState(true),
+		)
+	}
+
 	for i, file := range files {
 		if v.ctx.Err() != nil {
 			return v.ctx.Err()
@@ -119,10 +143,14 @@ func (v *Vaultik) Restore(opts *RestoreOptions) error {
 		if err := v.restoreFile(v.ctx, repos, file, opts.TargetDir, identity, chunkToBlobMap, blobCache, result); err != nil {
 			log.Error("Failed to restore file", "path", file.Path, "error", err)
 			// Continue with other files
-			continue
 		}
 
-		// Progress logging
+		// Update progress bar
+		if bar != nil {
+			_ = bar.Add64(file.Size)
+		}
+
+		// Progress logging (for non-terminal or structured logs)
 		if (i+1)%100 == 0 || i+1 == len(files) {
 			log.Info("Restore progress",
 				"files", fmt.Sprintf("%d/%d", i+1, len(files)),
@@ -131,6 +159,10 @@ func (v *Vaultik) Restore(opts *RestoreOptions) error {
 		}
 	}
 
+	if bar != nil {
+		_ = bar.Finish()
+	}
+
 	result.Duration = time.Since(startTime)
 
 	log.Info("Restore complete",
@@ -473,6 +505,53 @@ func (v *Vaultik) restoreRegularFile(
 	return nil
 }
 
+// BlobFetchResult holds the result of fetching and decrypting a blob.
+type BlobFetchResult struct {
+	Data           []byte
+	CompressedSize int64
+}
+
+// FetchAndDecryptBlob downloads a blob from storage, decrypts and decompresses it.
+func (v *Vaultik) FetchAndDecryptBlob(ctx context.Context, blobHash string, expectedSize int64, identity age.Identity) (*BlobFetchResult, error) {
+	// Construct blob path with sharding
+	blobPath := fmt.Sprintf("blobs/%s/%s/%s", blobHash[:2], blobHash[2:4], blobHash)
+
+	reader, err := v.Storage.Get(ctx, blobPath)
+	if err != nil {
+		return nil, fmt.Errorf("downloading blob: %w", err)
+	}
+	defer func() { _ = reader.Close() }()
+
+	// Read encrypted data
+	encryptedData, err := io.ReadAll(reader)
+	if err != nil {
+		return nil, fmt.Errorf("reading blob data: %w", err)
+	}
+
+	// Decrypt and decompress
+	blobReader, err := blobgen.NewReader(bytes.NewReader(encryptedData), identity)
+	if err != nil {
+		return nil, fmt.Errorf("creating decryption reader: %w", err)
+	}
+	defer func() { _ = blobReader.Close() }()
+
+	data, err := io.ReadAll(blobReader)
+	if err != nil {
+		return nil, fmt.Errorf("decrypting blob: %w", err)
+	}
+
+	log.Debug("Downloaded and decrypted blob",
+		"hash", blobHash[:16],
+		"encrypted_size", humanize.Bytes(uint64(len(encryptedData))),
+		"decrypted_size", humanize.Bytes(uint64(len(data))),
+	)
+
+	return &BlobFetchResult{
+		Data:           data,
+		CompressedSize: int64(len(encryptedData)),
+	}, nil
+}
+
 // downloadBlob downloads and decrypts a blob
 func (v *Vaultik) downloadBlob(ctx context.Context, blobHash string, expectedSize int64, identity age.Identity) ([]byte, error) {
 	result, err := v.FetchAndDecryptBlob(ctx, blobHash, expectedSize, identity)

internal/vaultik/snapshot.go

@@ -4,8 +4,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
-	"regexp"
 	"path/filepath"
+	"regexp"
 	"sort"
 	"strings"
 	"text/tabwriter"

internal/vaultik/vaultik.go

@@ -135,6 +135,34 @@ func (v *Vaultik) Outputf(format string, args ...any) {
 	_, _ = fmt.Fprintf(v.Stdout, format, args...)
 }
 
+// printfStdout writes formatted output to stdout.
+func (v *Vaultik) printfStdout(format string, args ...any) {
+	_, _ = fmt.Fprintf(v.Stdout, format, args...)
+}
+
+// printlnStdout writes a line to stdout.
+func (v *Vaultik) printlnStdout(args ...any) {
+	_, _ = fmt.Fprintln(v.Stdout, args...)
+}
+
+// scanlnStdin reads a line from stdin into the provided string pointer.
+func (v *Vaultik) scanlnStdin(s *string) error {
+	_, err := fmt.Fscanln(v.Stdin, s)
+	return err
+}
+
+// FetchBlob downloads a blob from storage and returns a reader for the encrypted data.
+func (v *Vaultik) FetchBlob(ctx context.Context, blobHash string, expectedSize int64) (io.ReadCloser, int64, error) {
+	blobPath := fmt.Sprintf("blobs/%s/%s/%s", blobHash[:2], blobHash[2:4], blobHash)
+
+	reader, err := v.Storage.Get(ctx, blobPath)
+	if err != nil {
+		return nil, 0, fmt.Errorf("downloading blob: %w", err)
+	}
+
+	return reader, expectedSize, nil
+}
+
 // TestVaultik wraps a Vaultik with captured stdout/stderr for testing
 type TestVaultik struct {
 	*Vaultik