/************************************************************
 *                                                          *
 * BlackJack - 21 - A Card Game                             *
 *                                                          *
 ************************************************************
 * AUTHOR: Jay Deuel                              *
 *   DATE: July 5, 2001                           *
 **************************************************/


/**************************************************
 *                                                *
 * Declare and Initialize Variables               *
 *                                                *
 **************************************************/

var gameStatus = 0;                                // game in progress
var endScenario = 0;                               // indicates reason for end of game
var cardImage = new Image;                         // image of card to be displayed

var playerBet = 1;                                 // amount of bet for current hand
var doubleBet = 1;                                 // indicates Double Down
var playerTotal = 100;                             // balance player has or owes

var playerInsurance = false;                       // player insurance against dealer BlackJack
var playerScore = 0;                               // value of player hand
var playerAce = 0;                                 // Aces in player hand
var playerHand = new Array(8); playerHand[0] = 0;  // number of cards delt to player
                                                   // value of individual card in player hand
                               playerHand[1] = 0; playerHand[2] = 0; playerHand[3] = 0; playerHand[4] = 0; playerHand[5] = 0; playerHand[6] = 0; playerHand[7] = 0;

var dealerScore = 0;                               // value of dealer hand
var dealerAce = 0;                                 // Aces in dealer hand
var dealerImage = new Image;                       // image of dealer 2nd card (delt face-down)
var dealerHand = new Array(8); dealerHand[0] = 0;  // number of cards delt to dealer
                                                   // value of individual card in dealer hand
                               dealerHand[1] = 0; dealerHand[2] = 0; dealerHand[3] = 0; dealerHand[4] = 0; dealerHand[5] = 0; dealerHand[6] = 0; dealerHand[7] = 0;

var randomNumber = 0;                              // random number for shuffle
var cardStack = new Array(53); cardStack[00] = 52; // number of cards delt from the top of current deck
                                                   // value of individual card in deck
                               cardStack[01] = 01; cardStack[02] = 02; cardStack[03] = 03; cardStack[04] = 04; cardStack[05] = 05; cardStack[06] = 06; cardStack[07] = 07; cardStack[08] = 08; cardStack[09] = 09; cardStack[10] = 10; cardStack[11] = 11; cardStack[12] = 12; cardStack[13] = 13;
                               cardStack[14] = 14; cardStack[15] = 15; cardStack[16] = 16; cardStack[17] = 17; cardStack[18] = 18; cardStack[19] = 19; cardStack[20] = 20; cardStack[21] = 21; cardStack[22] = 22; cardStack[23] = 23; cardStack[24] = 24; cardStack[25] = 25; cardStack[26] = 26;
                               cardStack[27] = 27; cardStack[28] = 28; cardStack[29] = 29; cardStack[30] = 30; cardStack[31] = 31; cardStack[32] = 32; cardStack[33] = 33; cardStack[34] = 34; cardStack[35] = 35; cardStack[36] = 36; cardStack[37] = 37; cardStack[38] = 38; cardStack[39] = 39;
                               cardStack[40] = 40; cardStack[41] = 41; cardStack[42] = 42; cardStack[43] = 43; cardStack[44] = 44; cardStack[45] = 45; cardStack[46] = 46; cardStack[47] = 47; cardStack[48] = 48; cardStack[49] = 49; cardStack[50] = 50; cardStack[51] = 51; cardStack[52] = 52;

/**************************************************
 *                                                *
 * Deal Cards                                     *
 *                                                *
 **************************************************/

function dealCards()
         {
          if (gameStatus == 0)
             {
              newGame();
              if (cardStack[00] > 39)                      // maximum number of cards needed per game: 6 player, 7 dealer
                 {
                  shuffleDeck()
                 }

              scoreCard("player",++playerHand[0],cardStack[++cardStack[00]]);     // player 1st card: who, position, face
              scoreCard("dealer",++dealerHand[0],cardStack[++cardStack[00]]);     // dealer 1st card: who, position, face
              scoreCard("player",++playerHand[0],cardStack[++cardStack[00]]);     // player 2nd card: who, position, face
              scoreCard("dealer",++dealerHand[0],cardStack[++cardStack[00]]);     // dealer 2nd card: who, position, face
              
              top.display.message.document.forms[0].update.value = "";
              top.display.message.document.forms[0].action.value = " Stand, Hit Me or Double Down";
              top.display.message.document.forms[0].status.value = "     Cards in the deck: " + (52 - cardStack[00]);
              top.display.player.document.forms[0].hand.value = "Player: " + playerScore;

              if ((playerAce > 0) || (dealerAce > 0))
                 {
                  checkNatural();
                 }
             }
          else
             {
              alert("Deal cards to begin a new game, but not during one-in-progress!");
             }
         }

/**************************************************
 *                                                *
 * Stand with Current Hand                        *
 *                                                *
 **************************************************/

function lastStand()
         {
          if (gameStatus == 1)
             {
              displayCard(0,2,dealerImage.src,dealerHand[2]);

              if ((playerAce > 0) && ((playerScore + 10) <= 21))
                 {
                  playerScore += 10;                                                          // count player Ace as 11
                 }

              if (endScenario == 0)
                 {
                  while (dealerScore <= 16)                                                   // play dealer hand, hard 17+
                        {
                         if ((dealerAce > 0) && (((dealerScore + 10) >= 17) && ((dealerScore + 10) <= 21)))     // soft 17+
                            {
                             dealerScore += 10;                                               // count dealer Ace as 11
                            }
                         else if ((dealerHand[0] >= 7) && (dealerScore <= 21))                // dealer wins with 7 cards
                            {
                             endScenario = 10;                                                // dealer did not bust
                            }
                         else
                            {
                             scoreCard("dealer",++dealerHand[0],cardStack[++cardStack[00]]);  // who, position, face
                            }
                        }
                  top.display.message.document.forms[0].status.value = "     Cards in the deck: " + (52 - cardStack[00]);

                  if (dealerScore > 21)
                     {
                      endScenario = 3;                                                        // dealer busted
                      playerTotal += (playerBet * doubleBet);
                     }
                  else if (playerScore > dealerScore)
                     {
                      endScenario = 2;                                                        // player wins
                      playerTotal += (playerBet * doubleBet);
                     }
                  else if (playerScore < dealerScore)
                     {
                      endScenario = 8;                                                        // dealer wins
                      playerTotal -= (playerBet * doubleBet);
                     }
                  else if (playerScore == dealerScore)
                     {
                      endScenario = 1;                                                        // player and dealer equal
                     }
                  else
                     {
                      endScenario = 99;                                                       // error
                     }
                 }

              if (endScenario == 5)                                                           // player wins with BlackJack!
                 {
                  playerTotal += (playerBet * 1.5);
                 }
              endGame();
             }
          else
             {
              alert("Stand can only happen during a game-in-progress!");
             }
         }

/**************************************************
 *                                                *
 * Hit Me with Another Card                       *
 *                                                *
 **************************************************/

function hitMe()
         {
          if (gameStatus == 1)
             {
              scoreCard("player",++playerHand[0],cardStack[++cardStack[00]]);     // player 3rd card: who, position, face
              top.display.message.document.forms[0].status.value = "     Cards in the deck: " + (52 - cardStack[00]);

              if (playerScore > 21)
                 {
                  playerTotal -= playerBet;
                  endScenario = 9;                                                // player busted
                  lastStand();
                 }
              else if ((playerHand[0] >= 7) && (playerScore <= 21))               // player dealt 7 cards, and did not bust
                 {
                  playerTotal += playerBet;
                  endScenario = 4;                                                // player wins with 7 cards
                  lastStand();
                 }
              else if ((playerAce > 0) && ((playerScore + 10) <= 21))
                 {
                  top.display.player.document.forms[0].hand.value = "Player: " + playerScore + " or " + (playerScore  + 10);
                 }
              else
                 {
                  top.display.player.document.forms[0].hand.value = "Player: " + playerScore;
                 }
             }
          else
             {
              alert("Hit Me can only happen during a game-in-progress!");
             }
         }

/**************************************************
 *                                                *
 * Change Bet and/or Total                        *
 *                                                *
 **************************************************/

function changeBet()
         {
          if (gameStatus == 0)
             {
              playerBet = eval(prompt("Change the current bet to what value?","1"));
              top.display.message.document.forms[0].bet.value = "Bet: " + playerBet;

              playerTotal = eval(prompt("Change the current bet to what value?","100"));
              top.display.message.document.forms[0].total.value = "Total: " + playerTotal;
             }
          else
             {
              alert("Change Bet can not happen during a game-in-progress!");
             }
         }

/**************************************************
 *                                                *
 * Double Down                                    *
 *                                                *
 **************************************************/

function doubleDown()
         {
          if (gameStatus == 1)
             {
              if (playerHand[0] > 2)
                 {
                  alert("Double Down can only happen before Player is delt a 3rd card!");
                 }
              else
                 {
                  doubleBet = 2; 
                  scoreCard("player",++playerHand[0],cardStack[++cardStack[00]]);     // player 3rd card: who, position, face
                  top.display.message.document.forms[0].status.value = "     Cards in the deck: " + (52 - cardStack[00]);
                  if (playerScore > 21)
                     {
                      playerTotal -= (playerBet * doubleBet);
                      endScenario = 9;                                                // player busted
                     }
                  else
                     {
                      if (playerAce > 0)
                         {
                          if ((playerScore + 10) <= 21)
                             {
                              playerScore += 10;
                             }
                         }                                               // double down
                     }
                  lastStand();
                 }
             }
          else
             {
              alert("Double Down can only happen during a game-in-progress!");
             }
         }

/**************************************************
 *                                                *
 * New Game                                       *
 *                                                *
 **************************************************/

function newGame()
         {
          gameStatus = 1;
          doubleBet = 1;
          endScenario = 0;

          playerAce = 0;
          playerScore = 0;
          playerHand[0] = 0;
          playerInsurance = false;
          top.display.player.document.forms[0].hand.value = "Player: ";

          dealerAce = 0;
          dealerScore = 0;
          dealerHand[0] = 0;
          top.display.dealer.document.forms[0].hand.value = "Dealer: ";

          for (i = 0; i < 7; i++)
              {
               top.display.dealer.document.images[i].src = "cards/blank.gif";
               top.display.dealer.document.forms[0].elements[i + 1].value = "";
               top.display.player.document.images[i].src = "cards/blank.gif";
               top.display.player.document.forms[0].elements[i + 1].value = "";
              }
          top.display.message.document.left.src = "cards/blank.gif";
          top.display.message.document.right.src = "images/blank-r.gif";
         }

/**************************************************
 *                                                *
 * Shuffle Deck                                   *
 *                                                *
 **************************************************/

function shuffleDeck()
         {
          var sameCards = 0;

          top.display.message.document.left.src = "cards/back.jpg";
          top.display.message.document.forms[0].update.value = "  The deck is being shuffled.";
          top.display.message.document.forms[0].action.value = "";
          top.display.message.document.forms[0].status.value = "";

          for (i = 1; i <= 52; i++)
              {
               randomNumber = Math.round(Math.random() * 52);
               if (randomNumber == 0) {randomNumber = 52}             // even chance for all 52 combinations
               cardStack[i] = randomNumber;
               for (j = 1; j < i; j++)                                // assure 52 unique cards
                   {
                    if (cardStack[j] == cardStack[i]) {sameCards++}   // detect if card is not unique
                   }
               if (sameCards > 0)
                  {
                   i--;
                   sameCards = 0;
                  }
               else
                  {
                   top.display.message.document.forms[0].status.value = "     Cards in the deck: " + i;
                  }
              }

          top.display.message.document.left.src = "cards/blank.gif";
          cardStack[00] = 0;
         }

/**************************************************
 *                                                *
 * Score Card                                     *
 *                                                *
 **************************************************/

function scoreCard(a,b,c)                                                         // who, position-in-hand, card-face
         {          
          if (a == "player")                                                      // player card
             {
              playerHand[b] = determineValue(c);
              cardImage.src = "cards/" + determineSource(c) + ".gif"
              displayCard(2,b,cardImage.src,playerHand[b]);
              if (playerHand[b] == 1)                                             // face is an Ace
                 {
                  playerAce++
                 }
              playerScore += playerHand[b];
             }
          else                                                                    // dealer card
             {
              dealerHand[b] = determineValue(c);
              cardImage.src = "cards/" + determineSource(c) + ".gif"

              if (b == 2)                                                         // dealer 2nd card
                 {
                  dealerImage.src = cardImage.src;
                  top.display.dealer.document.images[1].src="cards/back.jpg";     // dealer 2nd card face-down
                 }
              else
                 {
                  displayCard(0,b,cardImage.src,dealerHand[b]);
                 }

              if (dealerHand[b] == 1)                                             // face is an Ace
                 {
                  dealerAce++
                 }

              dealerScore += dealerHand[b];
             }
         }

/**************************************************
 *                                                *
 * Determine Card Value                           *
 *                                                *
 **************************************************/

function determineValue(u)
         {
          switch (u)
                 {
                  case (01): return  1;
                  case (02): return  2;
                  case (03): return  3;
                  case (04): return  4;
                  case (05): return  5;
                  case (06): return  6;
                  case (07): return  7;
                  case (08): return  8;
                  case (09): return  9;
                  case (10): return 10;
                  case (11): return 10;
                  case (12): return 10;
                  case (13): return 10;
                  case (14): return  1;
                  case (15): return  2;
                  case (16): return  3;
                  case (17): return  4;
                  case (18): return  5;
                  case (19): return  6;
                  case (20): return  7;
                  case (21): return  8;
                  case (22): return  9;
                  case (23): return 10;
                  case (24): return 10;
                  case (25): return 10;
                  case (26): return 10;
                  case (27): return  1;
                  case (28): return  2;
                  case (29): return  3;
                  case (30): return  4;
                  case (31): return  5;
                  case (32): return  6;
                  case (33): return  7;
                  case (34): return  8;
                  case (35): return  9;
                  case (36): return 10;
                  case (37): return 10;
                  case (38): return 10;
                  case (39): return 10;
                  case (40): return  1;
                  case (41): return  2;
                  case (42): return  3;
                  case (43): return  4;
                  case (44): return  5;
                  case (45): return  6;
                  case (46): return  7;
                  case (47): return  8;
                  case (48): return  9;
                  case (49): return 10;
                  case (50): return 10;
                  case (51): return 10;
                  case (52): return 10;
                  default:   return 0;                  // invalid randomNumber
                 }
         }

/**************************************************
 *                                                *
 * Determine Card Image Source                    *
 *                                                *
 **************************************************/

function determineSource(v)
         {
          switch (v)
                 {
                  case (01): return "c-01";
                  case (02): return "c-02";
                  case (03): return "c-03";
                  case (04): return "c-04";
                  case (05): return "c-05";
                  case (06): return "c-06";
                  case (07): return "c-07";
                  case (08): return "c-08";
                  case (09): return "c-09";
                  case (10): return "c-10";
                  case (11): return "c-11";
                  case (12): return "c-12";
                  case (13): return "c-13";
                  case (14): return "d-01";
                  case (15): return "d-02";
                  case (16): return "d-03";
                  case (17): return "d-04";
                  case (18): return "d-05";
                  case (19): return "d-06";
                  case (20): return "d-07";
                  case (21): return "d-08";
                  case (22): return "d-09";
                  case (23): return "d-10";
                  case (24): return "d-11";
                  case (25): return "d-12";
                  case (26): return "d-13";
                  case (27): return "h-01";
                  case (28): return "h-02";
                  case (29): return "h-03";
                  case (30): return "h-04";
                  case (31): return "h-05";
                  case (32): return "h-06";
                  case (33): return "h-07";
                  case (34): return "h-08";
                  case (35): return "h-09";
                  case (36): return "h-10";
                  case (37): return "h-11";
                  case (38): return "h-12";
                  case (39): return "h-13";
                  case (40): return "s-01";
                  case (41): return "s-02";
                  case (42): return "s-03";
                  case (43): return "s-04";
                  case (44): return "s-05";
                  case (45): return "s-06";
                  case (46): return "s-07";
                  case (47): return "s-08";
                  case (48): return "s-09";
                  case (49): return "s-10";
                  case (50): return "s-11";
                  case (51): return "s-12";
                  case (52): return "s-13";
                  default:   return "joker";                  // invalid randomNumber
                 }
         }

/**************************************************
 *                                                *
 * Display Card                                   *
 *                                                *
 **************************************************/

function displayCard(w,x,y,z)     // FRAME, position-in-hand, card-face, card-value
         {
          top.display.frames[w].document.images[x-1].src = y;
          if (z == 10)
             {
              top.display.frames[w].document.forms[0].elements[x].value = " " + z;
             }
          else if (z > 1)
             {
              top.display.frames[w].document.forms[0].elements[x].value = "  " + z;
             }
          else
             {
              top.display.frames[w].document.forms[0].elements[x].value = "1/11";
             }
         }

/**************************************************
 *                                                *
 * Check for a Natural - BlackJack - 21           *
 *                                                *
 **************************************************/

function checkNatural()
         {
          if (((playerHand[1] == 1) && (playerHand[2] == 10)) || ((playerHand[1] == 10) && (playerHand[2] == 1)))
             {
              top.display.player.document.forms[0].hand.value = "Player: BJ - 21";
              playerScore += 10;
              endScenario = 5;                                                                  // Player Natural!
             }

          if ((dealerHand[1] == 1) && (endScenario != 5))
             {
              playerInsurance = confirm("Do you want to buy insurance against a dealer BlackJack?");
              if (playerInsurance == true)
                 {
                  playerTotal -= (playerBet * .5);
                  top.display.message.document.forms[0].total.value = "Total: " + playerTotal;
                 }
             }

          if (((dealerHand[1] == 1) && (dealerHand[2] == 10)) || ((dealerHand[1] == 10) && (dealerHand[2] == 1)))
             {
              top.display.dealer.document.forms[0].hand.value = "Dealer: BJ - 21";

              if (endScenario == 5)
                 {
                  endScenario = 6;                                                              // Player and Dealer Natural!
                 }
              else
                 {
                  playerTotal -= playerBet;
                  if (playerInsurance == true)
                     {
                      playerTotal += playerBet;
                     }
                  endScenario = 7;                                                              // Dealer Natural!
                 }
             }

          if (endScenario == 0)
             {
              if (playerAce > 0)                                                       // player has an Ace, not a natural
                 {
                  top.display.player.document.forms[0].hand.value = "Player: " + playerScore + " or " + (playerScore  + 10);
                 }
             }
          else
             {
              lastStand();
             }
         }

/**************************************************
 *                                                *
 * End Game                                       *
 *                                                *
 **************************************************/

function endGame()
         {
          if ((endScenario < 5) || (endScenario > 6))
             {
              top.display.player.document.forms[0].hand.value = "Player: " + playerScore;
             }

          if ((endScenario < 6) || (endScenario > 7))
             {
              top.display.dealer.document.forms[0].hand.value = "Dealer: " + dealerScore;
             }

          var leadingZero = "";                                                                    // notice comments herein
          if ((endScenario == 1))
             {
              top.display.message.document.right.src = "images/suits.gif";
             }
          else if ((endScenario >= 2) && (endScenario <= 4))
             {
              randomNumber = Math.round(Math.random() * 21);                                        // 21 right images
              if (randomNumber == 0) {randomNumber = 21}
              if (randomNumber < 10) {leadingZero += "0"}
              top.display.message.document.right.src = "images/display/r-" + leadingZero + randomNumber + ".gif";
             }
          else if ((endScenario >= 5) && (endScenario <= 7))
             {
              top.display.message.document.right.src = "images/bj.gif";
             }
          else
             {
              top.display.message.document.left.src = "cards/joker.gif";
             }

          var theMessage = "";
          switch (endScenario)
                 {
                  case (01): theMessage = " Push: Player and Dealer Equal"; break;
                  case (02): theMessage = "         Player Wins!         "; break;
                  case (03): theMessage = "  Player Wins: Dealer Busted! "; break;
                  case (04): theMessage = "Player Wins: 7 Cards - No Bust"; break;
                  case (05): theMessage = " Player Wins: Delt a Natural! "; break;
                  case (06): theMessage = "Tie: Player and Dealer Natural"; break;
                  case (07): theMessage = " Dealer Wins: Delt a Natural  "; break;
                  case (08): theMessage = "         Dealer Wins          "; break;
                  case (09): theMessage = "  Dealer Wins: Player Busted  "; break;
                  case (10): theMessage = "Dealer Wins: 7 Cards - No Bust"; break;
                  case (99): theMessage = "      ERROR: Dealer Hand      "; break;
                  default:  theMessage = "            ERROR!            ";                          // invalid endScenario
                            top.display.message.document.left.src = "cards/joker.gif";
                 }
          top.display.message.document.forms[0].update.value = theMessage;
          top.display.message.document.forms[0].action.value = "";
          top.display.message.document.forms[0].total.value = "Total: " + playerTotal;
          gameStatus = 0;
         }

/**************************************************
 *                                                *
 * The End                                        *
 *                                                *
 **************************************************/