Sync Poker (#2878)

This updates the Poker to be in sync with the problem specifications.

exercises/practice/poker/.meta/config.json

@@ -6,10 +6,12 @@
     "aadityakulkarni",
     "FridaTveit",
     "hgvanpariya",
+    "jagdish-15",
     "jmrunkle",
     "katmpatz",
     "kytrinyx",
     "lemoncurry",
+    "MartinDekanovsky",
     "mirkoperillo",
     "msomji",
     "muzimuzhi",
@@ -27,8 +29,6 @@
       "src/test/java/PokerTest.java"
     ],
     "example": [
-      ".meta/src/reference/java/Card.java",
-      ".meta/src/reference/java/Hand.java",
       ".meta/src/reference/java/Poker.java"
     ],
     "invalidator": [

exercises/practice/poker/.meta/src/reference/java/Poker.java

@@ -1,34 +1,132 @@
-import java.util.*;
-import java.util.stream.Collectors;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 
 class Poker {
-    private final List<String> bestHands;
 
-    Poker(final List<String> hands) {
-        bestHands = bestHands(hands);
+    private List<String> hands;
+    private List<Integer> numericalValues;
+    private List<Integer> counts;
+
+    public Poker(List<String> hands) {
+        this.hands = hands;
     }
 
-    List<String> getBestHands() {
+    public List<String> getBestHands() {
+        List<String> bestHands = new ArrayList<>();
+        bestHands.add(hands.get(0));
+
+        for (int i = 1; i < hands.size(); i++) {
+            if (getHandRank(hands.get(i)) > getHandRank(bestHands.get(0))) {
+                bestHands.set(0, hands.get(i));
+            } else if (getHandRank(hands.get(i)) == getHandRank(bestHands.get(0))) {
+                getHandRank(bestHands.get(0));
+                List<Integer> firstHand = counts;
+
+                getHandRank(hands.get(i));
+                List<Integer> secondHand = counts;
+
+                if (firstHand.equals(secondHand)) {
+                    bestHands.add(hands.get(i));
+                } else {
+                    for (int j = 4; j >= 2; j--) {
+                        if (firstHand.contains(j) && secondHand.contains(j)) {
+                            if (firstHand.lastIndexOf(j) < secondHand.lastIndexOf(j)) {
+                                bestHands.set(0, hands.get(i));
+                                break;
+                            } else if (firstHand.lastIndexOf(j) > secondHand.lastIndexOf(j)) {
+                                break;
+                            } else if (firstHand.lastIndexOf(j) == secondHand.lastIndexOf(j) && j == 2) {
+                                if (firstHand.indexOf(j) < secondHand.indexOf(j)) {
+                                    bestHands.set(0, hands.get(i));
+                                }
+                            }
+                        }
+                    }
+                    for (int k = firstHand.size() - 1; k >= 0; k--) {
+                        if (firstHand.get(k) <= 1 && secondHand.get(k) <= 1) {
+                            if (firstHand.get(k) < secondHand.get(k)) {
+                                bestHands.set(0, hands.get(i));
+                                break;
+                            } else if (firstHand.get(k) > secondHand.get(k)) {
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+        }
         return bestHands;
     }
 
-    private List<String> bestHands(final List<String> hands) {
-        ArrayList<Hand> scoredHands = new ArrayList<>();
+    public int getHandRank(String hand) {
+        String[] cards = hand.split(" ");
+        List<String> values = new ArrayList<>();
+        List<String> suits = new ArrayList<>();
+        for (String card : cards) {
+            if (card.length() == 2) {
+                values.add(card.substring(0, 1));
+                suits.add(card.substring(1));
+            } else {
+                values.add(card.substring(0, 2));
+                suits.add(card.substring(2));
+            }
+        }
+
+        for (int i = 0; i < values.size(); i++) {
+            switch (values.get(i)) {
+                case "J" -> values.set(i, "11");
+                case "Q" -> values.set(i, "12");
+                case "K" -> values.set(i, "13");
+                case "A" -> {
+                    if (values.contains("2") && values.contains("3") && values.contains("4") && values.contains("5")) {
+                        values.set(i, "1");
+                    } else {
+                        values.set(i, "14");
+                    }
+                }
+            }
+        }
+
+        numericalValues = new ArrayList<>();
+        for (String value : values) {
+            numericalValues.add(Integer.valueOf(value));
+        }
+        Collections.sort(numericalValues);
 
-        for (String s : hands) {
-            scoredHands.add(new Hand(s));
+        List<Integer> possibleValues = new ArrayList<>();
+        counts = new ArrayList<>();
+        for (int i = 1; i <= 14; i++) {
+            counts.add(i - 1, countOccurrences(i));
+            possibleValues.add(i);
         }
-        Optional<Integer> maxScoreIfAny = scoredHands
-                .stream()
-                .map(Hand::getScore)
-                .max(Comparator.naturalOrder());
-        return maxScoreIfAny
-                .map(maxScore -> scoredHands
-                        .stream()
-                        .filter(h -> h.getScore() == maxScore)
-                        .map(Hand::getInput)
-                        .collect(Collectors.toList()))
-                .orElseGet(Collections::emptyList);
 
+        boolean isStraight = Collections.indexOfSubList(possibleValues, numericalValues) != -1;
+
+        boolean isFlush = suits.stream().distinct().count() == 1;
+
+        if (isStraight & isFlush) {
+            return 8; // straight flush
+        } else if (counts.contains(4)) {
+            return 7; // four of a kind
+        } else if (counts.contains(3) && counts.contains(2)) {
+            return 6; // full house
+        } else if (isFlush) {
+            return 5; // flush
+        } else if (isStraight) {
+            return 4; // straight
+        } else if (counts.contains(3)) {
+            return 3; // three of a kind
+        } else if (counts.stream().filter(value -> value == 2).count() == 2) {
+            return 2; // two pair
+        } else if (counts.contains(2)) {
+            return 1; // pair
+        } else {
+            return 0; // high card
+        }
     }
+
+    public int countOccurrences(int valueToFind) {
+        return (int) numericalValues.stream().filter(value -> value.equals(valueToFind)).count();
+    }  
 }