Add isMensesStart

lib/cycle.js

@@ -133,6 +133,25 @@ export default function config(opts) {
     }
   }
 
+  function isMensesStart(cycleDay) {
+    if (!cycleDay.bleeding || cycleDay.bleeding.exclude) return false
+    const bleedingDays = bleedingDaysSortedByDate
+    if (noBleedingDayWithinThreshold(cycleDay)) {
+      return true
+    }
+    return false
+
+    function noBleedingDayWithinThreshold(day) {
+      const localDate = LocalDate.parse(day.date)
+      const threshold = localDate.minusDays(maxBreakInBleeding + 1).toString()
+      const index = bleedingDays.findIndex(day => day.date === cycleDay.date)
+      const previousBleedingDays = bleedingDays.slice(index + 1)
+      return !previousBleedingDays.some(day => {
+        return day.date >= threshold && !day.bleeding.exclude
+      })
+    }
+  }
+
   function getCycleLength(cycleStartDates) {
     const cycleLengths = []
     for (let i = 0; i < cycleStartDates.length - 1; i++) {
@@ -188,6 +207,7 @@ export default function config(opts) {
     getCyclesBefore,
     getAllMensesStarts,
     getCycleLength,
-    getPredictedMenses
+    getPredictedMenses,
+    isMensesStart
   }
 }