Merge branch 'master'

lib/sympto/cervix.js

@@ -0,0 +1,41 @@
+export default function (cycleDays, tempEvalEndIndex) {
+  const cervixDays = cycleDays.filter(day => day.cervix && !day.cervix.exclude)
+
+  for (let i = 0; i < cervixDays.length; i++) {
+    const day = cervixDays[i]
+    if (isClosedAndHard(day.cervix)) continue
+    // the three following days must be with closed and hard cervix
+    // AND no other cervix value may occur until temperature evaluation has
+    // been completed
+    const threeFollowingDays = cervixDays.slice(i + 1, i + 4)
+    if (threeFollowingDays.length < 3) continue
+
+    const fertileCervixOccursIn3FollowingDays = threeFollowingDays.some(day => {
+      return !isClosedAndHard(day.cervix)
+    })
+    if (fertileCervixOccursIn3FollowingDays) continue
+
+    const cycleDayIndex = cycleDays.indexOf(day)
+    const relevantDays = cycleDays
+      .slice(cycleDayIndex + 1, tempEvalEndIndex + 1)
+      .filter(day => day.cervix && !day.cervix.exclude)
+
+    const onlyClosedAndHardUntilEndOfTempEval = relevantDays.every(day => {
+      return isClosedAndHard(day.cervix)
+    })
+
+    if (onlyClosedAndHardUntilEndOfTempEval) {
+      return {
+        detected: true,
+        cervixPeak: day,
+        evaluationCompleteDay: threeFollowingDays[threeFollowingDays.length - 1]
+      }
+    }
+  }
+
+  return { detected: false }
+}
+
+function isClosedAndHard (cervixValue) {
+  return cervixValue.isClosed && cervixValue.isHard
+}