fix: correct Go time-format tokens for S3 object key date path

s3manager.go

@@ -179,11 +179,14 @@ func (m *S3Manager) GenerateS3Key(userID, contactJID, messageID string, mimeType
 	contactJID = strings.ReplaceAll(contactJID, "@", "_")
 	contactJID = strings.ReplaceAll(contactJID, ":", "_")
 
-	// Get current time
+	// Get current time. Go's reference time is "2006-01-02 15:04:05", so the
+	// layout tokens for year/month/day are "2006"/"01"/"02". The previous
+	// values ("2025"/"05"/"25") were not valid tokens — "05" is the seconds
+	// field — so media was filed under nonsensical, non-chronological folders.
 	now := time.Now()
-	year := now.Format("2025")
-	month := now.Format("05")
-	day := now.Format("25")
+	year := now.Format("2006")
+	month := now.Format("01")
+	day := now.Format("02")
 
 	// Determine media type folder
 	mediaType := "documents"

s3manager_test.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+)
+
+// TestGenerateS3KeyDateFormat verifies the fix for the S3 key date path: the
+// year/month/day segments must use valid Go layout tokens ("2006"/"01"/"02").
+// The previous code used "2025"/"05"/"25", which are not valid tokens ("05" is
+// the seconds field), producing a 5-digit "year" and nonsensical month/day.
+func TestGenerateS3KeyDateFormat(t *testing.T) {
+	m := &S3Manager{}
+	key := m.GenerateS3Key("user-1", "123456@s.whatsapp.net", "MSGID", "image/jpeg", true)
+
+	// Layout: users/{userID}/{direction}/{contactJID}/{year}/{month}/{day}/{mediaType}/{messageID}{ext}
+	parts := strings.Split(key, "/")
+	if len(parts) != 9 {
+		t.Fatalf("unexpected key shape %q (%d segments, want 9)", key, len(parts))
+	}
+	year, month, day := parts[4], parts[5], parts[6]
+
+	now := time.Now()
+	if want := now.Format("2006"); year != want {
+		t.Errorf("year segment = %q, want %q (key=%q)", year, want, key)
+	}
+	if want := now.Format("01"); month != want {
+		t.Errorf("month segment = %q, want %q (key=%q)", month, want, key)
+	}
+	if want := now.Format("02"); day != want {
+		t.Errorf("day segment = %q, want %q (key=%q)", day, want, key)
+	}
+
+	// Regression guard independent of the current date: the old bug produced a
+	// 5-digit "year" and a "month" rendered from seconds. Enforce exact widths.
+	if len(year) != 4 {
+		t.Errorf("year segment %q must be exactly 4 digits (key=%q)", year, key)
+	}
+	if len(month) != 2 || len(day) != 2 {
+		t.Errorf("month/day segments must be 2 digits, got %q/%q (key=%q)", month, day, key)
+	}
+}