From ab066b1bf6a6422b8927b1f35e28e33d8ac72aea Mon Sep 17 00:00:00 2001
From: Kresna <kresna@usetada.com>
Date: Sat, 1 Aug 2026 22:04:32 +0700
Subject: [PATCH] fix(optical-transfer): honest progress by frames collected,
 not solved blocks
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Reported: progress stayed 0% while many frames were captured. LT fountain codes
solve almost nothing until they avalanche near the end, so 'solved blocks ÷ total'
reads ~0% the whole time you collect frames — looks stuck.

Report progress by unique frames collected ÷ the ~k×1.15 typically needed
(LtDecoder.progress() + new framesSeen), capped below 100% until actually done.
The bar now climbs smoothly as frames come in, then completes on the avalanche.

592 tests · lint clean · build green.
---
 src/islands/network/OpticalTransfer.tsx |  9 ++-------
 src/tools/optical/fountain.lib.ts       | 14 +++++++++++++-
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/src/islands/network/OpticalTransfer.tsx b/src/islands/network/OpticalTransfer.tsx
index 8644ff6..7fa2edc 100644
--- a/src/islands/network/OpticalTransfer.tsx
+++ b/src/islands/network/OpticalTransfer.tsx
@@ -128,7 +128,6 @@ function Receiver({ onBack }: { onBack: () => void }) {
   useEffect(() => {
     if (!stream) return;
     if (!captureRef.current) captureRef.current = document.createElement('canvas');
-    let collected = 0;
 
     const scan = () => {
       const video = videoRef.current;
@@ -149,13 +148,9 @@ function Receiver({ onBack }: { onBack: () => void }) {
               decoderRef.current = new LtDecoder(frame.k, BLOCK_SIZE);
             }
             if (frame.session === metaRef.current.session && decoderRef.current) {
-              const before = decoderRef.current.solvedCount;
               const done = decoderRef.current.addFrame(frame.seq, frame.payload);
-              if (decoderRef.current.solvedCount !== before || decoderRef.current.progress() > 0) {
-                collected++;
-                setFrames(collected);
-                setProgress(decoderRef.current.progress());
-              }
+              setFrames(decoderRef.current.framesSeen);
+              setProgress(decoderRef.current.progress());
               if (done) finish();
             }
           }
diff --git a/src/tools/optical/fountain.lib.ts b/src/tools/optical/fountain.lib.ts
index 364b759..1c45bf7 100644
--- a/src/tools/optical/fountain.lib.ts
+++ b/src/tools/optical/fountain.lib.ts
@@ -127,8 +127,20 @@ export class LtDecoder {
     return this.solvedCount >= this.k;
   }
 
+  /** Unique frames received so far. */
+  get framesSeen(): number {
+    return this.seenSeq.size;
+  }
+
+  /**
+   * Collection progress 0..1. LT codes solve almost nothing until they avalanche
+   * near the end, so reporting solved-blocks looks stuck at 0%. Report frames
+   * collected vs. the ~k×1.15 typically needed instead (capped below 1 until done).
+   */
   progress(): number {
-    return this.k === 0 ? 1 : this.solvedCount / this.k;
+    if (this.done) return 1;
+    if (this.k === 0) return 1;
+    return Math.min(0.99, this.framesSeen / (this.k * 1.15));
   }
 
   /** Feed one frame. Returns true once the whole file is solved. */