Chunk manifest transfer: 1000 files per batch

Avoids bufio.Scanner token limit by sending manifest in batches.
Each batch is a separate JSON line with up to 1000 files.

1 files changed, 34 insertions, 8 deletions

diff --git a/cmd_windows.go b/cmd_windows.go
index 7df0a9b..dfe137a 100644
--- a/cmd_windows.go
+++ b/cmd_windows.go
@@ -275,16 +275,42 @@ func scanDirectory(root string, stack *GitignoreStack) *Manifest {
 }
 
 func sendManifest(conn net.Conn, manifest *Manifest) {
-	msg := &ProtocolMessage{
-		Type:  "manifest",
-		Files: manifest.ToJSON(),
+	const batchSize = 1000
+	files := make([]FileMetaJSON, 0, batchSize)
+	paths := make([]string, 0, batchSize)
+
+	for path, meta := range manifest.ToJSON() {
+		paths = append(paths, path)
+		files = append(files, meta)
+
+		if len(files) >= batchSize {
+			msg := &ProtocolMessage{
+				Type:  "manifest_batch",
+				Files: make(map[string]FileMetaJSON),
+			}
+			for i, p := range paths {
+				msg.Files[p] = files[i]
+			}
+			data, _ := EncodeMessage(msg)
+			data = append(data, '\n')
+			conn.Write(data)
+			files = files[:0]
+			paths = paths[:0]
+		}
 	}
-	data, err := EncodeMessage(msg)
-	if err != nil {
-		return
+
+	if len(files) > 0 {
+		msg := &ProtocolMessage{
+			Type:  "manifest_batch",
+			Files: make(map[string]FileMetaJSON),
+		}
+		for i, p := range paths {
+			msg.Files[p] = files[i]
+		}
+		data, _ := EncodeMessage(msg)
+		data = append(data, '\n')
+		conn.Write(data)
 	}
-	data = append(data, '\n')
-	conn.Write(data)
 
 	done := &ProtocolMessage{Type: "manifest_done"}
 	doneData, _ := EncodeMessage(done)