fix(tell): strip stale tell state on tab activation

OnTabActivated clears the runtime tell state the game-side detour leaves on a tab (CurrentChannel tell target + partner label) when a DIFFERENT tab becomes the input surface, so a normal typed line can no longer route as a silent /tell to the old partner. Re-clicking the active tab and tabs carrying their own Tab.TellTarget binding (leg1) are preserved.

All four activation paths route through it: Sidebar, TopTabBar, ChannelPopoutPool.TryOpen, and the MainWindow draw-seed. EnsureCurrentChannel becomes a pure derive-helper reached only via OnTabActivated. Adds the TellResetOnActivateStep self-test (step count 29 -> 30).

HellionChat/Plugin.cs

@@ -405,6 +405,7 @@ public sealed class Plugin : IAsyncDalamudPlugin
                 new SelfTests.SidebarGreetedGlyphStep(this),
                 new SelfTests.SidebarSectionHeaderStep(this),
                 new SelfTests.ScrollSnapDecisionStep(this),
+                new SelfTests.TellResetOnActivateStep(),
             ]);
 
             // Re-surface the wizard for existing users when a major UX

HellionChat/SelfTests/TellResetOnActivateStep.cs

@@ -0,0 +1,149 @@
+using Dalamud.Bindings.ImGui;
+using Dalamud.Game.Text.SeStringHandling;
+using Dalamud.Plugin.SelfTest;
+using HellionChat.Code;
+using HellionChat.GameFunctions.Types;
+using HellionChat.Util;
+
+namespace HellionChat.SelfTests;
+
+// F1: the activation strip. Drives the REAL OnTabActivated — the entry the
+// Sidebar/TopTabBar click handlers, the pop-out path and the Draw-seed all call
+// — with local probe tabs (Plugin.Config.Tabs is never touched). Asserts the
+// five contracts: strip-on-switch, no-strip-on-reclick (TR-4), leg1 preserve,
+// derive, and non-tell untouched.
+internal sealed class TellResetOnActivateStep : ISelfTestStep
+{
+    public string Name => "Hellion Chat - Tell reset on tab activate";
+
+    public SelfTestStepResult RunStep()
+    {
+        var other = MakeSayTab();
+
+        // (a) switching ONTO a stale-tell tab with no Tab-level binding strips the
+        // runtime tell state (target + partner label) and re-derives the channel.
+        var stale = MakeStaleTellTab(boundTellTarget: false, withLabel: true);
+        TabLifecycleHelpers.OnTabActivated(stale, other);
+        if (stale.CurrentChannel.TellTarget is not null)
+        {
+            ImGui.Text("(a) stale tell target not cleared on switch");
+            return SelfTestStepResult.Fail;
+        }
+        if (stale.CurrentChannel.Channel != InputChannel.Say)
+        {
+            ImGui.Text($"(a) channel not re-derived to Say, got {stale.CurrentChannel.Channel}");
+            return SelfTestStepResult.Fail;
+        }
+        if (stale.CurrentChannel.Name.Count != 0)
+        {
+            ImGui.Text("(a) stale partner label not cleared");
+            return SelfTestStepResult.Fail;
+        }
+
+        // (b) re-clicking the already-active tab (previous == tab) must NOT strip
+        // a live game-tell conversation (TR-4 regression guard).
+        var reclick = MakeStaleTellTab(boundTellTarget: false, withLabel: false);
+        TabLifecycleHelpers.OnTabActivated(reclick, reclick);
+        if (reclick.CurrentChannel.TellTarget is null)
+        {
+            ImGui.Text("(b) re-click wrongly stripped the active tell tab");
+            return SelfTestStepResult.Fail;
+        }
+        if (reclick.CurrentChannel.Channel != InputChannel.Tell)
+        {
+            ImGui.Text("(b) re-click wrongly changed the active tab's channel");
+            return SelfTestStepResult.Fail;
+        }
+
+        // (c) a tab whose own Tab.TellTarget is set is a real binding (leg1):
+        // channel + runtime target survive a switch.
+        var bound = MakeStaleTellTab(boundTellTarget: true, withLabel: false);
+        TabLifecycleHelpers.OnTabActivated(bound, other);
+        if (bound.CurrentChannel.TellTarget is null)
+        {
+            ImGui.Text("(c) bound tell tab wrongly stripped");
+            return SelfTestStepResult.Fail;
+        }
+        if (bound.CurrentChannel.Channel != InputChannel.Tell)
+        {
+            ImGui.Text("(c) bound tell tab channel wrongly changed");
+            return SelfTestStepResult.Fail;
+        }
+
+        // (d) an Invalid-channel tab just derives (pre-existing semantics).
+        var invalid = MakeSayTab();
+        TabLifecycleHelpers.OnTabActivated(invalid, other);
+        if (invalid.CurrentChannel.Channel != InputChannel.Say)
+        {
+            ImGui.Text(
+                $"(d) invalid-channel tab not derived, got {invalid.CurrentChannel.Channel}"
+            );
+            return SelfTestStepResult.Fail;
+        }
+
+        // (e) a non-tell tab is left untouched. Seed it with runtime tell state
+        // AND a label so a guard that wrongly fired on non-tell tabs would null
+        // them — the channel re-derive alone could not mask that regression.
+        var say = MakeSayTab();
+        say.CurrentChannel.SetChannel(InputChannel.Say);
+        say.CurrentChannel.TellTarget = new TellTarget("Untouched", 21, 0, TellReason.Direct);
+        var sayLabel = new SeStringBuilder().AddText("Untouched@World").Build();
+        say.CurrentChannel.Name = ChunkUtil
+            .ToChunks(sayLabel, ChunkSource.Content, ChatType.Say)
+            .ToList();
+        TabLifecycleHelpers.OnTabActivated(say, other);
+        if (say.CurrentChannel.Channel != InputChannel.Say)
+        {
+            ImGui.Text("(e) non-tell tab channel wrongly changed");
+            return SelfTestStepResult.Fail;
+        }
+        if (say.CurrentChannel.TellTarget is null || say.CurrentChannel.Name.Count == 0)
+        {
+            ImGui.Text("(e) non-tell tab runtime state wrongly stripped");
+            return SelfTestStepResult.Fail;
+        }
+
+        return SelfTestStepResult.Pass;
+    }
+
+    // A tab carrying runtime tell state the way the game-side detour leaves it:
+    // CurrentChannel.Channel == Tell with a resolvable CurrentChannel.TellTarget,
+    // optionally with the partner-name label chunks. boundTellTarget controls
+    // whether the Tab-level TellTarget marks it a real binding (leg1).
+    private static Tab MakeStaleTellTab(bool boundTellTarget, bool withLabel)
+    {
+        var tab = new Tab
+        {
+            Name = "selftest-activate-tell",
+            TellTarget = boundTellTarget
+                ? new TellTarget("Bound", 21, 0, TellReason.Direct)
+                : TellTarget.Empty(),
+            SelectedChannels = new Dictionary<ChatType, (ChatSource, ChatSource)>
+            {
+                [ChatType.Say] = (ChatSourceExt.All, ChatSourceExt.All),
+            },
+        };
+        tab.CurrentChannel.SetChannel(InputChannel.Tell);
+        tab.CurrentChannel.TellTarget = new TellTarget("Stale", 21, 0, TellReason.Direct);
+        if (withLabel)
+        {
+            var ss = new SeStringBuilder().AddText("Stale@World").Build();
+            tab.CurrentChannel.Name = ChunkUtil
+                .ToChunks(ss, ChunkSource.Content, ChatType.Say)
+                .ToList();
+        }
+        return tab;
+    }
+
+    private static Tab MakeSayTab() =>
+        new()
+        {
+            Name = "selftest-activate-say",
+            SelectedChannels = new Dictionary<ChatType, (ChatSource, ChatSource)>
+            {
+                [ChatType.Say] = (ChatSourceExt.All, ChatSourceExt.All),
+            },
+        };
+
+    public void CleanUp() { }
+}

HellionChat/Ui/Components/Sidebar.cs

@@ -247,8 +247,9 @@ internal sealed class Sidebar
         var rowHovered = ImGui.IsItemHovered();
         if (ImGui.IsItemClicked())
         {
+            var previous = activeTab;
             activeTab = tab;
-            TabLifecycleHelpers.EnsureCurrentChannel(tab);
+            TabLifecycleHelpers.OnTabActivated(tab, previous);
         }
 
         dl.DrawHoverSheen(

HellionChat/Ui/Components/TopTabBar.cs

@@ -34,8 +34,9 @@ internal sealed class TopTabBar
                 )
             )
             {
+                var previous = activeTab;
                 activeTab = tab;
-                TabLifecycleHelpers.EnsureCurrentChannel(tab);
+                TabLifecycleHelpers.OnTabActivated(tab, previous);
             }
 
             TabContextMenu.Draw(tab, $"toptab_ctx_{i}", _pool);

HellionChat/Ui/Windows/ChannelPopoutPool.cs

@@ -1,3 +1,4 @@
+using HellionChat.Util;
 using Microsoft.Extensions.Logging;
 
 namespace HellionChat.Ui.Windows;
@@ -40,6 +41,12 @@ internal sealed class ChannelPopoutPool
 
     public bool TryOpen(Tab tab)
     {
+        // A popped tab gets its own input bar, so strip stale tell state first —
+        // otherwise a popped-out stale-tell tab would be a send surface that
+        // bypasses the click-path activation strip. Previous = the main window's
+        // active tab; popping the active tab itself must not strip (TR-4 guard).
+        TabLifecycleHelpers.OnTabActivated(tab, Plugin.Instance.MainWindow?.ActiveTab);
+
         var slot = _slots.TryReserve(tab.Identifier);
         if (slot < 0)
         {

HellionChat/Ui/Windows/MainWindow.cs

@@ -156,7 +156,13 @@ internal sealed class MainWindow : Window
         // First-frame seed: the active tab defaults to the first persisted
         // tab so the message list isn't empty on a clean session.
         if (_activeTab is null && Plugin.Config.Tabs.Count > 0)
-            _activeTab = Plugin.Config.Tabs[0];
+        {
+            var seeded = Plugin.Config.Tabs[0];
+            _activeTab = seeded;
+            // The seeded Tabs[0] is the likeliest legacy stale-tell carrier
+            // (pre-coupling the detour wrote here); strip it like any activation.
+            TabLifecycleHelpers.OnTabActivated(seeded, null);
+        }
 
         var statusHeight = Components.StatusBar.Height;
 

HellionChat/Util/TabLifecycleHelpers.cs

@@ -17,8 +17,35 @@ internal static class TabLifecycleHelpers
 
     public static bool ShouldStripOnSave(Tab t) => IsInUnpinnedPool(t);
 
-    // Shared by the click paths (Sidebar, TopTabBar) and the keybind tab-cycle
-    // path so every entry point resolves a tab's channel identically (no drift).
+    // Stale-tell strip + channel derive, run at every tab activation. When a
+    // DIFFERENT tab becomes the input surface, drop any runtime tell state the
+    // game-side detour left on it (the CurrentChannel tell target plus the
+    // partner-name label) so a normal typed line cannot route as a silent /tell
+    // to the old partner — the same privacy guard StripTellBindingOnPromote
+    // applies on promote. Re-activating the already-active tab must NOT strip
+    // (a live game-tell would lose its context, TR-4); a tab carrying its own
+    // Tab.TellTarget is a real tell binding (leg1) and is left intact.
+    internal static void OnTabActivated(Tab tab, Tab? previous)
+    {
+        if (
+            !ReferenceEquals(tab, previous)
+            && tab.CurrentChannel.Channel == InputChannel.Tell
+            && tab.TellTarget?.IsSet() != true
+        )
+        {
+            tab.CurrentChannel.SetChannel(InputChannel.Invalid);
+            tab.CurrentChannel.TellTarget = null;
+            tab.CurrentChannel.ResetTempChannel();
+            // Label chunks carry the partner name after a game-side tell.
+            tab.CurrentChannel.Name = [];
+        }
+
+        EnsureCurrentChannel(tab);
+    }
+
+    // Pure derive-helper: resolves a tab's input channel from its
+    // SelectedChannels when none is set yet. Reached only via OnTabActivated
+    // now, so the strip and the derive stay in lockstep at every entry.
     internal static void EnsureCurrentChannel(Tab tab)
     {
         if (tab.CurrentChannel.Channel != InputChannel.Invalid)