1 files changed, 14 insertions, 4 deletions
diff --git a/src/qr.js b/src/qr.js
index fe49a02..d02aed3 100644
--- a/src/qr.js
+++ b/src/qr.js
@@ -6,10 +6,20 @@ import qrcode from 'qrcode-generator';
 // ec: error-correction level. 'M' by default; pass 'L' for long payloads (e.g.
 // gift links) where a smaller, chunkier grid scans more easily — on-screen QRs
 // are scanned immediately and don't need the damage tolerance of higher levels.
-export function qrSvg(text, { margin = 2, ec = 'M' } = {}) {
-  const qr = qrcode(0, ec); // type 0 = auto-size
-  qr.addData(text);
-  qr.make();
+// mode: pass 'Alphanumeric' for an all-uppercase QR-alphanumeric string (0-9 A-Z
+// space $%*+-./:) to pack it at 5.5 bits/char instead of byte mode's 8 — a much
+// smaller grid for the same data. Falls back to byte mode if the text doesn't fit.
+export function qrSvg(text, { margin = 2, ec = 'M', mode } = {}) {
+  let qr;
+  try {
+    qr = qrcode(0, ec);
+    qr.addData(text, mode);
+    qr.make();
+  } catch {
+    qr = qrcode(0, ec); // mode mismatch (e.g. a non-alphanumeric char) — plain byte mode
+    qr.addData(text);
+    qr.make();
+  }
 
   const count = qr.getModuleCount();
   const size = count + margin * 2;