[JS][5kyu] Blackjack Scorer

codewars/5kyu/blackjack-scorer/koronya.js

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+// [JS][5kyu] Blackjack Scorer
+// blackjack-scorer
+// https://www.codewars.com/kata/534ffb35edb1241eda0015fe/train/javascript
+
+const scoreHand = (cards) => {
+  const withoutAceList = cards.filter((card) => card !== 'A')
+  const aceList = cards.filter((card) => card === 'A')
+
+  const withoutAceScore = withoutAceList.reduce((acc, card) => {
+    if (['J', 'Q', 'K'].includes(card)) {
+      return acc + 10
+    }
+    return acc + parseInt(card, 10)
+  }, 0)
+
+  const aceLength = aceList.length
+  if (aceLength === 0) {
+    return withoutAceScore
+  }
+
+  const untilMaxScore = 21 - withoutAceScore
+  if (untilMaxScore >= aceLength * 11) {
+    return withoutAceScore + aceLength * 11
+  }
+
+  if (untilMaxScore < 11) {
+    return withoutAceScore + aceLength
+  }
+
+  const adjustScore = untilMaxScore > aceLength + 10 ? aceLength + 10 : aceLength
+  return withoutAceScore + adjustScore
+}
+
+
+
+scoreHand(['2', '3']) === 5
+scoreHand(['7', '7', '8']) === 22
+scoreHand(['4', '7', '8']) === 19
+
+// should score J, Q and K as 10
+scoreHand(['K', 'J', 'Q']) === 30
+
+// should core hands with Aces correctly
+scoreHand(['A', '3']) === 14
+scoreHand(['A', 'A']) === 12
+scoreHand(['A', '2', 'A', '9', '9']) === 22
+
+scoreHand(['7', '9', 'A']) === 17
+scoreHand(['3', 'A', 'A', '7']) === 12
+scoreHand(['K', 'A']) === 21
+scoreHand(['A', 'A']) === 12