From 059d791d8bf48f2b8b63b539e59e866b90d0c77e Mon Sep 17 00:00:00 2001
From: igneum-labs <337424239+igneum-labs@users.noreply.github.com>
Date: Sun, 4 Oct 2026 15:02:24 +0000
Subject: [PATCH] Prover service: with nothing assigned, an open shard (past
 its exclusive window, spec 7.2 item 4) is proven; the tile says open

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
---
 app/igneum-app/src/prover.rs | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/app/igneum-app/src/prover.rs b/app/igneum-app/src/prover.rs
index 1320de4ad..d85268646 100644
--- a/app/igneum-app/src/prover.rs
+++ b/app/igneum-app/src/prover.rs
@@ -34,6 +34,8 @@ pub struct Work {
     pub pgas: u64,
     pub tx_count: u64,
     pub assigned: bool,
+    /// Past the exclusive window: anyone may prove it (spec 7.2 item 4).
+    pub open: bool,
     pub paid: bool,
     pub in_pool: bool,
     pub shard_wei: u128,
@@ -54,6 +56,7 @@ pub fn parse_work(v: &Value) -> Vec<Work> {
                     pgas: hexu(&w["pgas"]) as u64,
                     tx_count: w["txCount"].as_u64().unwrap_or(0),
                     assigned: w["assigned"].as_bool().unwrap_or(false),
+                    open: w["open"].as_bool().unwrap_or(false),
                     paid: !w["paid"].is_null(),
                     in_pool: w["pool"].as_array().map(|p| !p.is_empty()).unwrap_or(false),
                     shard_wei: hexu(&w["shardWei"]),
@@ -66,10 +69,15 @@ pub fn parse_work(v: &Value) -> Vec<Work> {
 
 /// The shard to prove next: assigned to one of our keys, unpaid, not already in the pool from us, not attempted
 /// in this session; the newest first (its exclusive window is the one still open), the smallest among equals.
+/// With nothing assigned, an open shard (spec 7.2 item 4: past its exclusive window, unpaid, anyone may prove it),
+/// so a machine with no weight in the window still earns on what the assignees left.
 pub fn choose(work: &[Work], attempted: &HashSet<(String, u32)>) -> Option<Work> {
-    let mut c: Vec<&Work> = work.iter().filter(|w| w.assigned && !w.paid && !w.in_pool && !attempted.contains(&(w.hash.clone(), w.shard))).collect();
-    c.sort_by(|a, b| b.number.cmp(&a.number).then(a.pgas.cmp(&b.pgas)));
-    c.first().map(|w| (*w).clone())
+    let pick = |want_assigned: bool| {
+        let mut c: Vec<&Work> = work.iter().filter(|w| (if want_assigned { w.assigned } else { w.open }) && !w.paid && !w.in_pool && !attempted.contains(&(w.hash.clone(), w.shard))).collect();
+        c.sort_by(|a, b| b.number.cmp(&a.number).then(a.pgas.cmp(&b.pgas)));
+        c.first().map(|w| (*w).clone())
+    };
+    pick(true).or_else(|| pick(false))
 }
 
 /// A Windows path as WSL sees it: `C:\Users\x\f` -> `/mnt/c/Users/x/f`.
@@ -354,7 +362,7 @@ fn loop_forever(shared: Arc<Shared>, bin_dir: PathBuf) {
         let Some(w) = choose(&work, &attempted) else {
             set(&shared, |p| {
                 p.status = if submitted.is_empty() { "idle".into() } else { "submitted".into() };
-                p.message = if assigned == 0 { "no shard assigned to this machine in the last 60 blocks".into() } else { "every assigned shard is proven or paid".into() };
+                p.message = if assigned == 0 { "no shard assigned to this machine and none open in the last 60 blocks".into() } else { "every assigned and open shard is proven or paid".into() };
             });
             continue;
         };
@@ -371,7 +379,7 @@ fn loop_forever(shared: Arc<Shared>, bin_dir: PathBuf) {
         let started = Instant::now();
         set(&shared, |p| {
             p.status = "proving".into();
-            p.current = format!("block {} shard {} ({} txs, {} pgas)", w.number, w.shard, w.tx_count, w.pgas);
+            p.current = format!("block {} shard {} ({} txs, {} pgas{})", w.number, w.shard, w.tx_count, w.pgas, if w.assigned { "" } else { ", open" });
             p.started_at = crate::platform::unix_now_f();
             p.message = "exporting the chain and cutting the shard".into();
         });
@@ -469,7 +477,7 @@ mod tests {
     #[test]
     fn chooses_the_newest_unpaid_assigned_shard_not_yet_attempted() {
         let v: Value = serde_json::from_str(r#"[
-            {"number":"0x20","hash":"0xa","shard":0,"pgas":"0x640","txCount":1,"assigned":true,"assignedKeys":["0xk1"],"paid":null,"pool":[],"shardWei":"0x10"},
+            {"number":"0x20","hash":"0xa","shard":0,"pgas":"0x640","txCount":1,"assigned":true,"open":false,"assignedKeys":["0xk1"],"paid":null,"pool":[],"shardWei":"0x10"},
             {"number":"0x1f","hash":"0xb","shard":1,"pgas":"0x10","txCount":0,"assigned":true,"assignedKeys":["0xk1"],"paid":null,"pool":[{"keyHash":"0xk1"}],"shardWei":"0x10"},
             {"number":"0x1e","hash":"0xc","shard":0,"pgas":"0x10","txCount":0,"assigned":true,"assignedKeys":["0xk2"],"paid":{"wei":"0x1"},"pool":[],"shardWei":"0x10"},
             {"number":"0x1d","hash":"0xd","shard":0,"pgas":"0x10","txCount":0,"assigned":false,"assignedKeys":[],"paid":null,"pool":[],"shardWei":"0x10"},