From cf7401919488bc3af3bc3033c5843a948d02b769 Mon Sep 17 00:00:00 2001
From: Meta Vens <rwvens@hotmail.com>
Date: Sun, 11 Oct 2026 20:23:59 +0200
Subject: [PATCH] Mill votes: the very-busy refusal offers sign-in to a voter
 who is not signed in

Accounts have their own table, so signing in works while the cast or mint
table is full. A signed-in voter is not told to sign in. Pinned through the
full pipeline at a small cap, for both audiences.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
---
 src/Bifrost.Web/Pages/Mill/Vote.cshtml.cs     | 15 +++++++----
 .../ConceptVoteRateLimitTests.cs              | 26 ++++++++++++++++++-
 2 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/src/Bifrost.Web/Pages/Mill/Vote.cshtml.cs b/src/Bifrost.Web/Pages/Mill/Vote.cshtml.cs
index f843f0a..dd87f6d 100644
--- a/src/Bifrost.Web/Pages/Mill/Vote.cshtml.cs
+++ b/src/Bifrost.Web/Pages/Mill/Vote.cshtml.cs
@@ -82,7 +82,7 @@ public sealed class VoteModel(
             return NotFound();
         }
 
-        if (Throttled(limits.DenyCast(HttpContext.Connection.RemoteIpAddress, voter), CastRefusal) is { } throttled)
+        if (Throttled(limits.DenyCast(HttpContext.Connection.RemoteIpAddress, voter), CastRefusal, voter) is { } throttled)
         {
             return throttled;
         }
@@ -105,14 +105,14 @@ public sealed class VoteModel(
             return NotFound();
         }
 
-        if (Throttled(limits.DenyCast(client, voter), CastRefusal) is { } throttled)
+        if (Throttled(limits.DenyCast(client, voter), CastRefusal, voter) is { } throttled)
         {
             return throttled;
         }
 
         if (voter is null)
         {
-            if (Throttled(limits.DenyMint(client), MintRefusal) is { } mintThrottled)
+            if (Throttled(limits.DenyMint(client), MintRefusal, voter) is { } mintThrottled)
             {
                 return mintThrottled;
             }
@@ -143,14 +143,19 @@ public sealed class VoteModel(
 
     private const string BusyRefusal = "Voting is very busy right now. Please try again in a little while.";
 
-    private IActionResult? Throttled(BudgetDenial? denial, string spentRefusal)
+    // Accounts have their own table, so a visitor who is not signed in can still vote by signing in while a table is full.
+    private const string BusyRefusalSignIn =
+        "Voting is very busy right now. You can sign in to vote now, or try again in a little while.";
+
+    private IActionResult? Throttled(BudgetDenial? denial, string spentRefusal, VoterIdentity? voter)
     {
         if (denial is not { } refused)
         {
             return null;
         }
 
-        var refusal = refused.TableFull ? BusyRefusal : spentRefusal;
+        var busy = voter?.UserAccountId is null ? BusyRefusalSignIn : BusyRefusal;
+        var refusal = refused.TableFull ? busy : spentRefusal;
         Response.Headers.RetryAfter = ((int)Math.Ceiling(refused.RetryAfter.TotalSeconds)).ToString(System.Globalization.CultureInfo.InvariantCulture);
         return new ContentResult
         {
diff --git a/tests/Bifrost.Web.Tests/ConceptVoteRateLimitTests.cs b/tests/Bifrost.Web.Tests/ConceptVoteRateLimitTests.cs
index 1cedf97..04cdff4 100644
--- a/tests/Bifrost.Web.Tests/ConceptVoteRateLimitTests.cs
+++ b/tests/Bifrost.Web.Tests/ConceptVoteRateLimitTests.cs
@@ -381,12 +381,36 @@ public sealed class ConceptVoteRateLimitTests : IClassFixture<ConceptVoteRateLim
         var body = await visitor.Content.ReadAsStringAsync();
         Assert.Contains("busy", body);
         Assert.DoesNotContain("too fast", body);
-        Assert.DoesNotContain("sign in", body, StringComparison.OrdinalIgnoreCase);
+        Assert.Contains("sign in", body, StringComparison.OrdinalIgnoreCase);
         Assert.DoesNotContain("203.0.113", body + string.Join(";", visitor.Headers.Select(h => string.Join(",", h.Value))));
         Assert.Equal(HttpStatusCode.Redirect, account.StatusCode);
         Assert.Equal(rowsBefore + 1, (await Rows(collection)).Count);
     }
 
+    [Fact]
+    public async Task A_full_account_table_refuses_a_new_account_as_busy_without_offering_sign_in()
+    {
+        var factory = Capped(4);
+        var collection = await NewSubject();
+        for (var i = 0; i < 4; i++)
+        {
+            var spender = new Client(factory, $"203.0.113.{150 + i}") { Account = ($"72{i:00}", $"spent-account-{i}") };
+            for (var cast = 0; cast < 3; cast++)
+            {
+                using var ok = await spender.Post(collection, "Up");
+                Assert.Equal(HttpStatusCode.Redirect, ok.StatusCode);
+            }
+        }
+
+        using var fresh = await new Client(factory, "203.0.113.160") { Account = ("7299", "fresh-signed-in") }
+            .Post(collection, "Up");
+
+        Assert.Equal(HttpStatusCode.TooManyRequests, fresh.StatusCode);
+        var body = await fresh.Content.ReadAsStringAsync();
+        Assert.Contains("busy", body);
+        Assert.DoesNotContain("sign in", body, StringComparison.OrdinalIgnoreCase);
+    }
+
     [Fact]
     public async Task Posts_to_a_missing_subject_spend_no_budget_and_mint_no_device()
     {