cleanups

card.go

@@ -19,55 +19,52 @@ func NewCardFromString(card string) (Card, error) {
 	// FIXME extend this later to common format strings like "9s"
 	length := utf8.RuneCountInString(card)
 	if length != 2 {
-		return Card{}, fmt.Errorf("Invalid card string %s", card)
-	}
-	var rank Rank
-	var suit Suit
-	if strings.ContainsRune(card, rune(SPADE)) {
-		suit = Suit(SPADE)
-	} else if strings.ContainsRune(card, rune(HEART)) {
-		suit = Suit(HEART)
-	} else if strings.ContainsRune(card, rune(DIAMOND)) {
-		suit = Suit(DIAMOND)
-	} else if strings.ContainsRune(card, rune(CLUB)) {
-		suit = Suit(CLUB)
-	} else {
-		return Card{}, fmt.Errorf("Invalid card string %s", card)
+		return Card{}, fmt.Errorf("invalid card string %s, must be 2 characters", card)
 	}
 
-	if strings.ContainsRune(card, rune(DEUCE)) {
-		rank = Rank(DEUCE)
-	} else if strings.ContainsRune(card, rune(THREE)) {
-		rank = Rank(THREE)
-	} else if strings.ContainsRune(card, rune(FOUR)) {
-		rank = Rank(FOUR)
-	} else if strings.ContainsRune(card, rune(FIVE)) {
-		rank = Rank(FIVE)
-	} else if strings.ContainsRune(card, rune(SIX)) {
-		rank = Rank(SIX)
-	} else if strings.ContainsRune(card, rune(SEVEN)) {
-		rank = Rank(SEVEN)
-	} else if strings.ContainsRune(card, rune(EIGHT)) {
-		rank = Rank(EIGHT)
-	} else if strings.ContainsRune(card, rune(NINE)) {
-		rank = Rank(NINE)
-	} else if strings.ContainsRune(card, rune(TEN)) {
-		rank = Rank(TEN)
-	} else if strings.ContainsRune(card, rune(JACK)) {
-		rank = Rank(JACK)
-	} else if strings.ContainsRune(card, rune(QUEEN)) {
-		rank = Rank(QUEEN)
-	} else if strings.ContainsRune(card, rune(KING)) {
-		rank = Rank(KING)
-	} else if strings.ContainsRune(card, rune(ACE)) {
-		rank = Rank(ACE)
-	} else {
-		return Card{}, fmt.Errorf("Invalid card string %s", card)
+	rankMap := map[rune]Rank{
+		rune(DEUCE): DEUCE,
+		rune(THREE): THREE,
+		rune(FOUR):  FOUR,
+		rune(FIVE):  FIVE,
+		rune(SIX):   SIX,
+		rune(SEVEN): SEVEN,
+		rune(EIGHT): EIGHT,
+		rune(NINE):  NINE,
+		rune(TEN):   TEN,
+		rune(JACK):  JACK,
+		rune(QUEEN): QUEEN,
+		rune(KING):  KING,
+		rune(ACE):   ACE,
+	}
+
+	suitMap := map[rune]Suit{
+		rune(SPADE):   SPADE,
+		rune(HEART):   HEART,
+		rune(DIAMOND): DIAMOND,
+		rune(CLUB):    CLUB,
+	}
+
+	var rank Rank
+	var suit Suit
+	for r := range rankMap {
+		if strings.ContainsRune(card, r) {
+			rank = rankMap[r]
+			break
+		}
+	}
+
+	for s := range suitMap {
+		if strings.ContainsRune(card, s) {
+			suit = suitMap[s]
+			break
+		}
 	}
 
 	if rank == Rank(0) || suit == Suit(0) {
-		return Card{}, fmt.Errorf("Invalid card string %s", card)
+		return Card{}, fmt.Errorf("invalid card string %s", card)
 	}
+
 	return Card{Rank: rank, Suit: suit}, nil
 }
 
@@ -75,18 +72,17 @@ func NewCardsFromString(cards string) (Cards, error) {
 	// supports a string like 9♠,9♣,Q♥,Q♦,K♣
 	// FIXME extend this later to common format strings like "9c Qh Qd Kc"
 	// with or without commas
-	var newCards Cards
-	newCards = make(Cards, 0)
 	cardStrings := strings.Split(cards, ",")
-	for _, cardString := range cardStrings {
+	newCards := make(Cards, len(cardStrings))
+	for i, cardString := range cardStrings {
 		card, err := NewCardFromString(cardString)
 		if err != nil {
-			return Cards{}, err
+			return nil, err
 		}
-		newCards = append(newCards, card)
+		newCards[i] = card
 	}
 	if len(newCards) == 0 {
-		return Cards{}, fmt.Errorf("No cards found in string %s", cards)
+		return nil, fmt.Errorf("no cards found in string %s", cards)
 	}
 	return newCards, nil
 }
@@ -97,42 +93,41 @@ func (c *Card) String() string {
 
 type Cards []Card
 
-func (c Cards) First() Card {
-	return c[0]
+func (cards Cards) First() Card {
+	return cards[0]
 }
 
-func (c Cards) Second() Card {
-	return c[1]
+func (cards Cards) Second() Card {
+	return cards[1]
 }
 
-func (c Cards) Third() Card {
-	return c[2]
+func (cards Cards) Third() Card {
+	return cards[2]
 }
 
-func (c Cards) Fourth() Card {
-	return c[3]
+func (cards Cards) Fourth() Card {
+	return cards[3]
 }
 
-func (c Cards) Fifth() Card {
-	return c[4]
+func (cards Cards) Fifth() Card {
+	return cards[4]
 }
 
-func (c Cards) Last() Card {
-	return c[len(c)-1]
+func (cards Cards) Last() Card {
+	return cards[len(cards)-1]
 }
 
-func (c Cards) SortByRankAscending() Cards {
-	newCards := make(Cards, len(c))
-	copy(newCards, c)
-	sort.Slice(newCards, func(i, j int) bool {
-		return newCards[i].Rank.Score() < newCards[j].Rank.Score()
+func (cards Cards) SortByRankAscending() Cards {
+	sortedCards := make(Cards, len(cards))
+	copy(sortedCards, cards)
+	sort.Slice(sortedCards, func(i, j int) bool {
+		return sortedCards[i].Rank.Score() < sortedCards[j].Rank.Score()
 	})
-
-	return newCards
+	return sortedCards
 }
 
-func (c Cards) PrintToTerminal() {
-	fmt.Printf("%s", c.FormatForTerminal())
+func (cards Cards) PrintToTerminal() {
+	fmt.Printf("%s", cards.FormatForTerminal())
 }
 
 type SortOrder int
@@ -142,18 +137,18 @@ const (
 	AceHighDescending
 )
 
-func (c Cards) FormatForTerminalSorted(order SortOrder) string {
-	sorted := c.SortByRankAscending() // this is ascending
+func (cards Cards) FormatForTerminalSorted(order SortOrder) string {
+	sorted := cards.SortByRankAscending() // this is ascending
 	if order == AceHighDescending {
 		slices.Reverse(sorted)
 	}
 	return sorted.FormatForTerminal()
 }
 
-func (c Cards) FormatForTerminal() string {
+func (cards Cards) FormatForTerminal() string {
 	var cardstrings []string
-	for i := 0; i < len(c); i++ {
-		cardstrings = append(cardstrings, c[i].FormatForTerminal())
+	for i := 0; i < len(cards); i++ {
+		cardstrings = append(cardstrings, cards[i].FormatForTerminal())
 	}
 	return strings.Join(cardstrings, ",")
 }
@@ -178,16 +173,15 @@ func (c Card) FormatForTerminal() string {
 	return fmt.Sprintf("%s%s", rank, suit)
 }
 
-func (c Cards) HighestRank() Rank {
-	sorted := c.SortByRankAscending()
+func (cards Cards) HighestRank() Rank {
+	sorted := cards.SortByRankAscending()
 	return sorted[len(sorted)-1].Rank
 }
 
-func (s Cards) String() (output string) {
+func (cards Cards) String() string {
 	var cardstrings []string
-	for i := 0; i < len(s); i++ {
-		cardstrings = append(cardstrings, s[i].String())
+	for i := 0; i < len(cards); i++ {
+		cardstrings = append(cardstrings, cards[i].String())
 	}
-	output = strings.Join(cardstrings, ",")
-	return output
+	return strings.Join(cardstrings, ",")
 }