Cuckoo: single click gives one call, double-click strikes the hour

Nine cuckoos on an idle click is a lot. There's no singleclick event and click
always fires before dblclick, so the single call is deferred by one double-click
interval (260ms) and cancelled if a second click lands.

docs-site/src/components/CuckooClock.astro

@@ -25,8 +25,8 @@
     class="cuckoo__btn"
     id="cuckoo-clock"
     type="button"
-    aria-label="Cuckoo clock — click to strike the hour"
-    title="Strike the hour"
+    aria-label="Cuckoo clock. Click for one call; double-click to strike the hour."
+    title="Click for one call · double-click strikes the hour"
   >
     <svg viewBox="0 0 200 272" class="cuckoo__svg" aria-hidden="true">
       <defs>
@@ -120,7 +120,9 @@
       </g>
     </svg>
 
-    <span class="cuckoo__hint">Strike the hour</span>
+    <span class="cuckoo__hint">
+      Click <span class="cuckoo__hint-sep">·</span> double-click strikes the hour
+    </span>
   </button>
 
   <p class="cuckoo__live" role="status" aria-live="polite" id="cuckoo-live"></p>
@@ -196,7 +198,7 @@
       return 0.78; // seconds until the next call may begin
     };
 
-    clock.addEventListener("click", async () => {
+    const strike = async (calls) => {
       if (striking) return;
       striking = true;
 
@@ -204,18 +206,42 @@
       ctx = ctx ?? new (window.AudioContext || window.webkitAudioContext)();
       if (ctx.state === "suspended") await ctx.resume();
 
-      const hour = new Date().getHours() % 12 || 12;
       let t = ctx.currentTime + 0.05;
-      for (let i = 0; i < hour; i++) t += call(t);
+      for (let i = 0; i < calls; i++) t += call(t);
 
       clock.classList.add("is-striking");
-      if (live) live.textContent = `Cuckoo ×${hour}`;
+      if (live) live.textContent = `Cuckoo ×${calls}`;
 
       const total = (t - ctx.currentTime) * 1000;
       setTimeout(() => {
         clock.classList.remove("is-striking");
         striking = false;
       }, total);
+    };
+
+    // A single click is a greeting: one call. Double-click and it strikes the
+    // hour properly — which at eleven o'clock is a commitment.
+    //
+    // There is no `singleclick` event, and `click` always fires BEFORE `dblclick`.
+    // So hold the single call for one double-click interval and cancel it if a
+    // second click lands. 260 ms is comfortably under the platform's threshold
+    // but longer than a deliberate double-tap.
+    let pending = null;
+
+    clock.addEventListener("click", () => {
+      if (pending) return; // this is the 2nd of a pair — let dblclick take it
+      pending = setTimeout(() => {
+        pending = null;
+        strike(1);
+      }, 260);
+    });
+
+    clock.addEventListener("dblclick", () => {
+      if (pending) {
+        clearTimeout(pending);
+        pending = null;
+      }
+      strike(new Date().getHours() % 12 || 12);
     });
   }
 </script>
@@ -260,6 +286,7 @@
     transition: color 0.2s;
   }
   .cuckoo__btn:hover .cuckoo__hint { color: var(--sl-color-accent); }
+  .cuckoo__hint-sep { opacity: 0.5; margin: 0 0.15em; }
 
   .cuckoo__live {
     min-height: 1.2em;