Qt Quick Demo - Same Game

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 /* This script file handles the game logic */
 .pragma library
 .import QtQuick.LocalStorage 2.0 as Sql

 var maxColumn = 10;
 var maxRow = 13;
 var types = 3;
 var maxIndex = maxColumn*maxRow;
 var board = new Array(maxIndex);
 var blockSrc = "Block.qml";
 var gameDuration;
 var component = Qt.createComponent(blockSrc);
 var gameCanvas;
 var betweenTurns = false;

 var puzzleLevel = null;
 var puzzlePath = "";

 var gameMode = "arcade"; //Set in new game, then tweaks behaviour of other functions
 var gameOver = false;

 function changeBlock(src)
 {
     blockSrc = src;
     component = Qt.createComponent(blockSrc);
 }

 // Index function used instead of a 2D array
 function index(column, row)
 {
     return column + row * maxColumn;
 }

 function timeStr(msecs)
 {
     var secs = Math.floor(msecs/1000);
     var m = Math.floor(secs/60);
     var ret = "" + m + "m " + (secs%60) + "s";
     return ret;
 }

 function cleanUp()
 {
     if (gameCanvas == undefined)
         return;
     // Delete blocks from previous game
     for (var i = 0; i < maxIndex; i++) {
         if (board[i] != null)
             board[i].destroy();
         board[i] = null;
     }
     if (puzzleLevel != null){
         puzzleLevel.destroy();
         puzzleLevel = null;
     }
     gameCanvas.mode = ""
 }

 function startNewGame(gc, mode, map)
 {
     gameCanvas = gc;
     if (mode == undefined)
         gameMode = "arcade";
     else
         gameMode = mode;
     gameOver = false;

     cleanUp();

     gc.gameOver = false;
     gc.mode = gameMode;
     // Calculate board size
     maxColumn = Math.floor(gameCanvas.width/gameCanvas.blockSize);
     maxRow = Math.floor(gameCanvas.height/gameCanvas.blockSize);
     maxIndex = maxRow * maxColumn;
     if (gameMode == "arcade") //Needs to be after board sizing
         getHighScore();

     // Initialize Board
     board = new Array(maxIndex);
     gameCanvas.score = 0;
     gameCanvas.score2 = 0;
     gameCanvas.moves = 0;
     gameCanvas.curTurn = 1;
     if (gameMode == "puzzle")
         loadMap(map);
     else//Note that we load them in reverse order for correct visual stacking
         for (var column = maxColumn - 1; column >= 0; column--)
             for (var row = maxRow - 1; row >= 0; row--)
                 createBlock(column, row);
     if (gameMode == "puzzle")
         getLevelHistory();//Needs to be after map load
     gameDuration = new Date();
 }

 var fillFound;  // Set after a floodFill call to the number of blocks found
 var floodBoard; // Set to 1 if the floodFill reaches off that node

 // NOTE: Be careful with vars named x,y, as the calling object's x,y are still in scope
 function handleClick(x,y)
 {
     if (betweenTurns || gameOver || gameCanvas == undefined)
         return;
     var column = Math.floor(x/gameCanvas.blockSize);
     var row = Math.floor(y/gameCanvas.blockSize);
     if (column >= maxColumn || column < 0 || row >= maxRow || row < 0)
         return;
     if (board[index(column, row)] == null)
         return;
     // If it's a valid block, remove it and all connected (does nothing if it's not connected)
     floodFill(column,row, -1);
     if (fillFound <= 0)
         return;
     if (gameMode == "multiplayer" && gameCanvas.curTurn == 2)
         gameCanvas.score2 += (fillFound - 1) * (fillFound - 1);
     else
         gameCanvas.score += (fillFound - 1) * (fillFound - 1);
     if (gameMode == "multiplayer" && gameCanvas.curTurn == 2)
         shuffleUp();
     else
         shuffleDown();
     gameCanvas.moves += 1;
     if (gameMode == "endless")
         refill();
     else if (gameMode != "multiplayer")
         victoryCheck();
     if (gameMode == "multiplayer" && !gc.gameOver){
         betweenTurns = true;
         gameCanvas.swapPlayers();//signal, animate and call turnChange() when ready
     }
 }

 function floodFill(column,row,type)
 {
     if (board[index(column, row)] == null)
         return;
     var first = false;
     if (type == -1) {
         first = true;
         type = board[index(column,row)].type;

         // Flood fill initialization
         fillFound = 0;
         floodBoard = new Array(maxIndex);
     }
     if (column >= maxColumn || column < 0 || row >= maxRow || row < 0)
         return;
     if (floodBoard[index(column, row)] == 1 || (!first && type != board[index(column, row)].type))
         return;
     floodBoard[index(column, row)] = 1;
     floodFill(column + 1, row, type);
     floodFill(column - 1, row, type);
     floodFill(column, row + 1, type);
     floodFill(column, row - 1, type);
     if (first == true && fillFound == 0)
         return; // Can't remove single blocks
     board[index(column, row)].dying = true;
     board[index(column, row)] = null;
     fillFound += 1;
 }

 function shuffleDown()
 {
     // Fall down
     for (var column = 0; column < maxColumn; column++) {
         var fallDist = 0;
         for (var row = maxRow - 1; row >= 0; row--) {
             if (board[index(column,row)] == null) {
                 fallDist += 1;
             } else {
                 if (fallDist > 0) {
                     var obj = board[index(column, row)];
                     obj.y = (row + fallDist) * gameCanvas.blockSize;
                     board[index(column, row + fallDist)] = obj;
                     board[index(column, row)] = null;
                 }
             }
         }
     }
     // Fall to the left
     fallDist = 0;
     for (column = 0; column < maxColumn; column++) {
         if (board[index(column, maxRow - 1)] == null) {
             fallDist += 1;
         } else {
             if (fallDist > 0) {
                 for (row = 0; row < maxRow; row++) {
                     obj = board[index(column, row)];
                     if (obj == null)
                         continue;
                     obj.x = (column - fallDist) * gameCanvas.blockSize;
                     board[index(column - fallDist,row)] = obj;
                     board[index(column, row)] = null;
                 }
             }
         }
     }
 }

 function shuffleUp()
 {
     // Fall up
     for (var column = 0; column < maxColumn; column++) {
         var fallDist = 0;
         for (var row = 0; row < maxRow; row++) {
             if (board[index(column,row)] == null) {
                 fallDist += 1;
             } else {
                 if (fallDist > 0) {
                     var obj = board[index(column, row)];
                     obj.y = (row - fallDist) * gameCanvas.blockSize;
                     board[index(column, row - fallDist)] = obj;
                     board[index(column, row)] = null;
                 }
             }
         }
     }
     // Fall to the left (or should it be right, so as to be left for P2?)
     fallDist = 0;
     for (column = 0; column < maxColumn; column++) {
         if (board[index(column, 0)] == null) {
             fallDist += 1;
         } else {
             if (fallDist > 0) {
                 for (row = 0; row < maxRow; row++) {
                     obj = board[index(column, row)];
                     if (obj == null)
                         continue;
                     obj.x = (column - fallDist) * gameCanvas.blockSize;
                     board[index(column - fallDist,row)] = obj;
                     board[index(column, row)] = null;
                 }
             }
         }
     }
 }

 function turnChange()//called by ui outside
 {
     betweenTurns = false;
     if (gameCanvas.curTurn == 1){
         shuffleUp();
         gameCanvas.curTurn = 2;
         victoryCheck();
     }else{
         shuffleDown();
         gameCanvas.curTurn = 1;
         victoryCheck();
     }
 }

 function refill()
 {
     for (var column = 0; column < maxColumn; column++) {
         for (var row = 0; row < maxRow; row++) {
             if (board[index(column, row)] == null)
                 createBlock(column, row);
         }
     }
 }

 function victoryCheck()
 {
     // Awards bonuses for no blocks left
     var deservesBonus = true;
     if (board[index(0,maxRow - 1)] != null || board[index(0,0)] != null)
         deservesBonus = false;
     // Checks for game over
     if (deservesBonus){
         if (gameCanvas.curTurn = 1)
             gameCanvas.score += 1000;
         else
             gameCanvas.score2 += 1000;
     }
     gameOver = deservesBonus;
     if (gameCanvas.curTurn == 1){
         if (!(floodMoveCheck(0, maxRow - 1, -1)))
             gameOver = true;
     }else{
         if (!(floodMoveCheck(0, 0, -1, true)))
             gameOver = true;
     }
     if (gameMode == "puzzle"){
         puzzleVictoryCheck(deservesBonus);//Takes it from here
         return;
     }
     if (gameOver) {
         var winnerScore = Math.max(gameCanvas.score, gameCanvas.score2);
         if (gameMode == "multiplayer"){
             gameCanvas.score = winnerScore;
             saveHighScore(gameCanvas.score2);
         }
         saveHighScore(gameCanvas.score);
         gameDuration = new Date() - gameDuration;
         gameCanvas.gameOver = true;
     }
 }

 // Only floods up and right, to see if it can find adjacent same-typed blocks
 function floodMoveCheck(column, row, type, goDownInstead)
 {
     if (column >= maxColumn || column < 0 || row >= maxRow || row < 0)
         return false;
     if (board[index(column, row)] == null)
         return false;
     var myType = board[index(column, row)].type;
     if (type == myType)
         return true;
     if (goDownInstead)
         return floodMoveCheck(column + 1, row, myType, goDownInstead) ||
                floodMoveCheck(column, row + 1, myType, goDownInstead);
     else
         return floodMoveCheck(column + 1, row, myType) ||
                floodMoveCheck(column, row - 1, myType);
 }

 function createBlock(column,row,type)
 {
     // Note that we don't wait for the component to become ready. This will
     // only work if the block QML is a local file. Otherwise the component will
     // not be ready immediately. There is a statusChanged signal on the
     // component you could use if you want to wait to load remote files.
     if (component.status == 1){
         if (type == undefined)
             type = Math.floor(Math.random() * types);
         if (type < 0 || type > 4) {
             console.log("Invalid type requested");//TODO: Is this triggered by custom levels much?
             return;
         }
         var dynamicObject = component.createObject(gameCanvas,
                 {"type": type,
                 "x": column*gameCanvas.blockSize,
                 "y": -1*gameCanvas.blockSize,
                 "width": gameCanvas.blockSize,
                 "height": gameCanvas.blockSize,
                 "particleSystem": gameCanvas.ps});
         if (dynamicObject == null){
             console.log("error creating block");
             console.log(component.errorString());
             return false;
         }
         dynamicObject.y = row*gameCanvas.blockSize;
         dynamicObject.spawned = true;

         board[index(column,row)] = dynamicObject;
     }else{
         console.log("error loading block component");
         console.log(component.errorString());
         return false;
     }
     return true;
 }

 function showPuzzleError(str)
 {
     //TODO: Nice user visible UI?
     console.log(str);
 }

 function loadMap(map)
 {
     puzzlePath = map;
     var levelComp = Qt.createComponent(puzzlePath);
     if (levelComp.status != 1){
         console.log("Error loading level");
         showPuzzleError(levelComp.errorString());
         return;
     }
     puzzleLevel = levelComp.createObject();
     if (puzzleLevel == null || !puzzleLevel.startingGrid instanceof Array) {
         showPuzzleError("Bugger!");
         return;
     }
     gameCanvas.showPuzzleGoal(puzzleLevel.goalText);
     //showPuzzleGoal should call finishLoadingMap as the next thing it does, before handling more events
 }

 function finishLoadingMap()
 {
     for (var i in puzzleLevel.startingGrid)
         if (! (puzzleLevel.startingGrid[i] >= 0 && puzzleLevel.startingGrid[i] <= 9) )
             puzzleLevel.startingGrid[i] = 0;
     //TODO: Don't allow loading larger levels, leads to cheating
     while (puzzleLevel.startingGrid.length > maxIndex) puzzleLevel.startingGrid.shift();
     while (puzzleLevel.startingGrid.length < maxIndex) puzzleLevel.startingGrid.unshift(0);
     for (var i in puzzleLevel.startingGrid)
         if (puzzleLevel.startingGrid[i] > 0)
             createBlock(i % maxColumn, Math.floor(i / maxColumn), puzzleLevel.startingGrid[i] - 1);

     //### Experimental feature - allow levels to contain arbitrary QML scenes as well!
     //while (puzzleLevel.children.length)
     //    puzzleLevel.children[0].parent = gameCanvas;
     gameDuration = new Date(); //Don't start until we finish loading
 }

 function puzzleVictoryCheck(clearedAll)//gameOver has also been set if no more moves
 {
     var won = true;
     var soFar = new Date() - gameDuration;
     if (puzzleLevel.scoreTarget != -1 && gameCanvas.score < puzzleLevel.scoreTarget){
         won = false;
     } if (puzzleLevel.scoreTarget != -1 && gameCanvas.score >= puzzleLevel.scoreTarget && !puzzleLevel.mustClear){
         gameOver = true;
     } if (puzzleLevel.timeTarget != -1 && soFar/1000.0 > puzzleLevel.timeTarget){
         gameOver = true;
     } if (puzzleLevel.moveTarget != -1 && gameCanvas.moves >= puzzleLevel.moveTarget){
         gameOver = true;
     } if (puzzleLevel.mustClear && gameOver && !clearedAll) {
         won = false;
     }

     if (gameOver) {
         gameCanvas.gameOver = true;
         gameCanvas.showPuzzleEnd(won);

         if (won) {
             // Store progress
             saveLevelHistory();
         }
     }
 }

 function getHighScore()
 {
     var db = Sql.LocalStorage.openDatabaseSync(
         "SameGame",
         "2.0",
         "SameGame Local Data",
         100
     );
     db.transaction(
         function(tx) {
             tx.executeSql('CREATE TABLE IF NOT EXISTS Scores(game TEXT, score NUMBER, gridSize TEXT, time NUMBER)');
             // Only show results for the current grid size
             var rs = tx.executeSql('SELECT * FROM Scores WHERE gridSize = "'
                 + maxColumn + "x" + maxRow + '" AND game = "' + gameMode + '" ORDER BY score desc');
             if (rs.rows.length > 0)
                 gameCanvas.highScore = rs.rows.item(0).score;
             else
                 gameCanvas.highScore = 0;
         }
     );
 }

 function saveHighScore(score)
 {
     // Offline storage
     var db = Sql.LocalStorage.openDatabaseSync(
         "SameGame",
         "2.0",
         "SameGame Local Data",
         100
     );
     var dataStr = "INSERT INTO Scores VALUES(?, ?, ?, ?)";
     var data = [
         gameMode,
         score,
         maxColumn + "x" + maxRow,
         Math.floor(gameDuration / 1000)
     ];
     if (score >= gameCanvas.highScore)//Update UI field
         gameCanvas.highScore = score;

     db.transaction(
         function(tx) {
             tx.executeSql('CREATE TABLE IF NOT EXISTS Scores(game TEXT, score NUMBER, gridSize TEXT, time NUMBER)');
             tx.executeSql(dataStr, data);
         }
     );
 }

 function getLevelHistory()
 {
     var db = Sql.LocalStorage.openDatabaseSync(
         "SameGame",
         "2.0",
         "SameGame Local Data",
         100
     );
     db.transaction(
         function(tx) {
             tx.executeSql('CREATE TABLE IF NOT EXISTS Puzzle(level TEXT, score NUMBER, moves NUMBER, time NUMBER)');
             var rs = tx.executeSql('SELECT * FROM Puzzle WHERE level = "' + puzzlePath + '" ORDER BY score desc');
             if (rs.rows.length > 0) {
                 gameCanvas.puzzleWon = true;
                 gameCanvas.highScore = rs.rows.item(0).score;
             } else {
                 gameCanvas.puzzleWon = false;
                 gameCanvas.highScore = 0;
             }
         }
     );
 }

 function saveLevelHistory()
 {
     var db = Sql.LocalStorage.openDatabaseSync(
         "SameGame",
         "2.0",
         "SameGame Local Data",
         100
     );
     var dataStr = "INSERT INTO Puzzle VALUES(?, ?, ?, ?)";
     var data = [
         puzzlePath,
         gameCanvas.score,
         gameCanvas.moves,
         Math.floor(gameDuration / 1000)
     ];
     gameCanvas.puzzleWon = true;

     db.transaction(
         function(tx) {
             tx.executeSql('CREATE TABLE IF NOT EXISTS Puzzle(level TEXT, score NUMBER, moves NUMBER, time NUMBER)');
             tx.executeSql(dataStr, data);
         }
     );
 }

 function nuke() //For "Debug mode"
 {
     for (var row = 1; row <= 5; row++) {
         for (var col = 0; col < 5; col++) {
             if (board[index(col, maxRow - row)] != null) {
                 board[index(col, maxRow - row)].dying = true;
                 board[index(col, maxRow - row)] = null;
             }
         }
     }
     if (gameMode == "multiplayer" && gameCanvas.curTurn == 2)
         shuffleUp();
     else
         shuffleDown();
     if (gameMode == "endless")
         refill();
     else
         victoryCheck();
 }