Added GoldFish Card Game smart contract

contracts/Games/goldfish.sol

@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.7;
+
+contract Goldfish {
+
+    struct Player {
+      uint[] hand; //the cards in the player's hand
+      uint score; //the player's score
+    }
+
+    Player[] public players; //the two players in the game
+    uint[] public drawPile; //the cards remaining in the draw pile
+    uint[] public discardPile; //the cards in the discard pile
+
+    //takes the top card from the draw pile and puts it in the discard pile
+    function drawCard() internal {
+      discardPile.push(uint256(drawPile.pop()))
+    };
+
+    //initializes the deck of cards
+    function initDeck() internal {
+      uint[] memory deck = new uint[52];
+
+      for (uint i = 0; i < 52; i++) {
+        deck[i] = i;
+      }
+
+      //shuffles the deck
+      for (uint i = 0; i < 52; i++) {
+        uint rand = uint(keccak256(block.number, now, i)) % 52;
+
+        drawPile = deck;
+      }
+    }
+
+    //initializes the two players
+    function initPlayers() internal { 
+      players.push(Player({
+        hand: new uint[](7),
+        score: 0
+      }));
+
+      players.push(Player({
+        hand: new uint[](7),
+        score: 0}));
+    }
+
+    //deals 7 cards to each player from the deck
+    function dealCards() internal {
+      for (uint i = 0; i < 7; i++) {
+        players[0].hand[i] = drawPile.pop();
+        players[1].hand[i] = drawPile.pop();
+      }
+
+    }
+
+  //returns the player's hand
+  function getHand(uint player) public view returns (uint[] memory ) {
+    return players[player].hand;
+  }
+
+  //returns true if the card can be played, false otherwise
+  function canPlayCard(uint card) public view returns (bool) {
+
+    //if the card is the same number or color as the top card of the discard pile, it can be played
+    if (card == discardPile[discardPile.length - 1]) {
+      return true;
+    }
+
+    //get the suit of the card
+    uint suit = card / 13;
+
+    //get the number of the card
+    uint number = card % 13;
+
+    //check if the player has any other cards of the same suit
+    for (uint i = 0; i < players[0].hand.length; i++) {
+
+      if (suit == players[0].hand[i] / 13 && card != players[0].hand[i]) {
+        return true;
+      }
+
+    }
+
+    //check if the player has any other cards of the same number
+    for (uint i = 0; i < players[0].hand.length; i++) {
+
+        if (number == players[0].hand[i] % 13 && card != players[0].hand[i]) {
+          return true;
+        }
+    }
+    return false;
+
+  }
+
+  //plays a card from the player's hand
+  function playCard(uint card) public {
+    require(canPlayCard(card));
+    discardPile.push(card);
+    removeFromHand(card);
+  }
+
+  //removes a card from the player's hand
+  function removeFromHand(uint card) internal {
+      for (uint i = 0; i < players[0].hand.length; i++) {
+        if (players[0].hand[i] == card) {
+          players[0].hand[i] = players[0].hand[players[0].hand.length - 1];
+          players[0].hand.length--;
+          return;
+      }
+    }
+  }
+
+  //returns the player's score
+  function getScore(uint player) public view returns (uint) { 
+    return players[player].score;
+  }
+
+  //calculates the score for the player who has no cards remaining
+  function calculateScore() internal {
+    uint player = 0;
+
+    if (players[1].hand.length == 0) {
+      player = 1;
+    }
+
+    players[player].score = players[player].score + players[1 - player].hand.length;
+
+  }
+
+  //ends the current turn
+  function endTurn() internal {
+    drawCard();
+
+    //if the player has no cards remaining, the game ends
+    if (players[0].hand.length == 0) {
+      calculateScore();
+    }
+
+  }
+
+  //called when the contract is created
+  constructor() public {
+    initDeck();
+    initPlayers();
+    dealCards();
+  }
+
+  //called when it is time for the player to make their move
+  function play() public {
+    uint card = players[0].hand[0];
+    playCard(card);
+    endTurn();
+  }
+
+}