feat: sine wave!

BREAKING CHANGE: extra anti-hack protection
ColinEberhardt · Sep 24, 2018 · 25fb09d · 25fb09d
1 parent ca620c4
commit 25fb09d
Showing 1 changed file with 12 additions and 1 deletion.
diff --git a/src/applause-button.js b/src/applause-button.js
@@ -10,14 +10,25 @@ const getClaps = url =>
     }
   }).then(response => response.text());
 
+
+const WAVELENGTH = 60 * 5;
+const secondsForClap = a => (WAVELENGTH * Math.asin(a / 10)) / (Math.PI * 2);
+
+const computeRequest = clapCount => {
+  const requiredSeconds = secondsForClap(clapCount);
+  const serverSeconds = (Date.now() / 1000) % 60;
+  const delta = requiredSeconds - serverSeconds;
+  return delta;
+}
+
 const updateClaps = (claps, url) =>
   // TODO: polyfill for IE (not edge)
   fetch(`${API}/update-claps` + (url ? `?url=${url}` : ""), {
     method: "POST",
     headers: {
       "Content-Type": "text/plain"
     },
-    body: JSON.stringify(claps)
+    body: JSON.stringify(computeRequest(claps))
   }).then(response => response.text());
 
 const arrayOfSize = size => new Array(size).fill(undefined);