fix(compact): size the window to the strip instead of a tuned constant

compactH was 158px, "tuned so the compact entry strip fits in a single row".
A constant tuned against a layout stops being true the moment the layout
changes, and this one outlived a strip that had since shrunk — leaving about
70px of empty window under the fields.

The frontend now measures what it rendered and asks for that height, watched by
a ResizeObserver so a strip that wraps at a narrow width is followed too. The
topbar is added as its declared h-8 rather than measured, since it is fixed.

Bounded in the backend: a measurement of zero — a layout not yet painted —
must not collapse the window, and the call is ignored unless compact is on so
nothing can shrink the normal window. Rounded to whole pixels so a sub-pixel
reflow cannot start a resize loop.

app.go

@@ -17774,3 +17774,29 @@ func (a *App) SetSpotTTLMinutes(min int) error {
 	a.setSetting(keyClusterSpotTTL, strconv.Itoa(min))
 	return nil
 }
+
+// SetCompactHeight resizes the compact window to fit its content.
+//
+// The height used to be a constant "tuned so the compact entry strip fits in a
+// single row". Constants tuned against a layout stop being true the moment the
+// layout changes, and this one outlived a strip that had since lost a row —
+// leaving a band of empty window under the fields. The frontend measures what
+// it actually rendered and says so.
+//
+// Ignored unless compact is on, so nothing can shrink the normal window.
+func (a *App) SetCompactHeight(h int) {
+	if a.ctx == nil || !a.compact {
+		return
+	}
+	// Bounded: a measurement of zero (a layout not yet painted) must not collapse
+	// the window to nothing, and no strip is ever 600px tall.
+	if h < 80 || h > 600 {
+		return
+	}
+	w, _ := wruntime.WindowGetSize(a.ctx)
+	if w <= 0 {
+		w = compactW
+	}
+	wruntime.WindowSetMinSize(a.ctx, 900, h)
+	wruntime.WindowSetSize(a.ctx, w, h)
+}

changelog.json

@@ -7,14 +7,16 @@
       "DX Cluster: a spot lifetime can be set — 5, 10, 15 minutes or your own value — after which spots leave the list and the band maps.",
       "Call lookup: QRZ.com now fills Name with the first name only, and optionally with the operator nickname instead.",
       "Entry form: a narrower left column, State beside the locator, and a new line with County, CQ, ITU and DXCC.",
-      "Station Control: the short and long path headings are repeated under the compass, at a readable size and clickable."
+      "Station Control: the short and long path headings are repeated under the compass, at a readable size and clickable.",
+      "Compact mode: the window now fits the entry strip instead of leaving a band of empty space below it."
     ],
     "fr": [
       "Cluster : « Masquer les contactés » ne masque plus un spot qui est un nouveau préfixe, comté, carré ou parc dans une contrée déjà faite.",
       "Cluster DX : on peut fixer une durée de vie des spots — 5, 10, 15 minutes ou une valeur libre — au-delà de laquelle ils quittent la liste et les band maps.",
       "Recherche d indicatif : QRZ.com remplit désormais Nom avec le seul prénom, et au choix avec le surnom de l opérateur.",
       "Saisie : colonne de gauche plus étroite, État à côté du locator, et une nouvelle ligne Comté, CQ, ITU et DXCC.",
-      "Contrôle station : les azimuts court et long chemin sont repris sous la boussole, lisibles et cliquables."
+      "Contrôle station : les azimuts court et long chemin sont repris sous la boussole, lisibles et cliquables.",
+      "Mode compact : la fenêtre épouse la bande de saisie au lieu de laisser une bande vide en dessous."
     ]
   },
   {

frontend/src/App.tsx

@@ -16,7 +16,7 @@ import {
   GetStartupStatus, CheckForUpdate, DownloadAndApplyUpdate, GetLiveStations, GetWhatsNew, GetChangelog,
   SMTPConfigured, SendLogToDeveloper,
   WorkedBefore,
-  SetCompactMode,
+  SetCompactMode, SetCompactHeight,
   GetCATState, SetCATFrequency, SetCATMode, SwitchCATRig, FlexApplyBandAntenna, FlexApplyBandPower,
   GetSecretStatus, UnlockSecrets,
   RefreshCtyDat, DownloadAllReferenceLists,
@@ -529,6 +529,28 @@ export default function App() {
     setCompact(next);
     SetCompactMode(next);
   }
+  // Fit the compact window to what was actually rendered.
+  //
+  // The height was a constant "tuned so the compact entry strip fits in a single
+  // row". A constant tuned against a layout stops being true the moment the
+  // layout changes, and this one outlived a strip that had since lost a row —
+  // leaving a band of empty window under the fields. Measure instead.
+  const compactRootRef = useRef<HTMLDivElement | null>(null);
+  useEffect(() => {
+    if (!compact) return;
+    const fit = () => {
+      const el = compactRootRef.current;
+      if (!el) return;
+      // Rounded, so a sub-pixel reflow cannot start a resize loop.
+      // + the compact topbar, which is a fixed h-8 (32px), + a couple of pixels
+      // for the border so the strip is never clipped by one row of anti-aliasing.
+      SetCompactHeight(Math.round(el.getBoundingClientRect().height) + 32 + 2);
+    };
+    const id = window.setTimeout(fit, 60); // let the strip paint first
+    const ro = new ResizeObserver(fit);
+    if (compactRootRef.current) ro.observe(compactRootRef.current);
+    return () => { window.clearTimeout(id); ro.disconnect(); };
+  }, [compact]);
 
   // CAT — receives live rig state via Wails events.
   const [catState, setCatState] = useState<CATState>({ enabled: false, connected: false } as any);
@@ -5892,7 +5914,7 @@ export default function App() {
           Enter from any <input> inside the strip logs the QSO. Radix Selects
           render as <button> elements and are ignored by this handler — they
           keep their own keyboard behaviour. */}
-      <div className={cn(!compact && 'flex gap-2.5 items-stretch px-2.5 pt-2.5 shrink-0')}>
+      <div ref={compactRootRef} className={cn(!compact && 'flex gap-2.5 items-stretch px-2.5 pt-2.5 shrink-0')}>
       <section
         className={cn('bg-card shadow-sm border-border',
           compact

frontend/wailsjs/go/main/App.d.ts

@@ -988,6 +988,8 @@ export function SetClublogMostWantedEnabled(arg1:boolean):Promise<void>;
 
 export function SetClusterAutoConnect(arg1:boolean):Promise<void>;
 
+export function SetCompactHeight(arg1:number):Promise<void>;
+
 export function SetCompactMode(arg1:boolean):Promise<void>;
 
 export function SetDVKLabel(arg1:number,arg2:string):Promise<void>;

frontend/wailsjs/go/main/App.js

@@ -1918,6 +1918,10 @@ export function SetClusterAutoConnect(arg1) {
   return window['go']['main']['App']['SetClusterAutoConnect'](arg1);
 }
 
+export function SetCompactHeight(arg1) {
+  return window['go']['main']['App']['SetCompactHeight'](arg1);
+}
+
 export function SetCompactMode(arg1) {
   return window['go']['main']['App']['SetCompactMode'](arg1);
 }