feat(pure): computeEstimate with safe division and target-reached handling

2026-06-01 15:30:07 -05:00
parent 545cf65beb
commit faae7702aa
2 changed files with 49 additions and 1 deletions
@@ -23,3 +23,16 @@ export function parseTarget(input) {
  const multiplier = suffix ? SUFFIXES[suffix] : 1;
  return Math.floor(num * multiplier);
 }
+
+export function computeEstimate(current, target, perTrain, perDay) {
+  const remaining = Math.max(0, target - current);
+  if (remaining === 0) {
+    return { remaining: 0, trainsToGo: 0, days: 0, eta: null };
+  }
+
+  const trainsToGo = perTrain > 0 ? Math.ceil(remaining / perTrain) : 0;
+  const days = perDay > 0 ? Math.ceil(remaining / perDay) : 0;
+  const eta = days > 0 ? new Date(Date.now() + days * 86_400_000) : null;
+
+  return { remaining, trainsToGo, days, eta };
+}