Game is now independent of GameState

src/Game.js

@@ -14,18 +14,13 @@
  * limitations under the License.
  */
 
-var Game = function(blobs, bounds, collision, state) {
+var Game = function(blobs, bounds, collision) {
     this.blobs     = blobs;
     this.bounds    = bounds;
     this.collision = collision;
-    this.state     = state;
 };
 
 Game.prototype.advance = function(input, gametime) {
-    if (!this.state.isRunning()) {
-        return this;
-    }
-
     var blobs = input.process(this.blobs);
 
     var movedBlobs = [];
@@ -38,9 +33,6 @@ Game.prototype.advance = function(input, gametime) {
         return b.mass() > 0;
     });
 
-    return new Game(blobsAfterCollisions, this.bounds, this.collision, this.state.transition(blobsAfterCollisions));
+    return new Game(blobsAfterCollisions, this.bounds, this.collision);
 }
 
-Game.prototype.status = function() {
-    return this.state.status();
-}

src/GameState.js

@@ -14,65 +14,11 @@
  * limitations under the License.
  */
 
-function GameState() {};
-
-GameState.prototype.transition = function(blobs) {
-    if (blobs.length === 0) {
-        return this.lose();
-    }
-    var playerBlobs = blobs.filter(function(b) {
-        return b.player > 0;
-    });
-    if (playerBlobs.length === 0) {
-        return this.lose();
-    }
-    // For now, we assume only one player...
-    var playerBlob = playerBlobs.shift();
-    if (!this.isWinningPossible(playerBlob, blobs)) {
-        return this.lose();
-    }
-
-    var biggestBlob = blobs.reduce(function(a, b) {
-        return a.mass() > b.mass() ? a : b;
-    });
-    var totalMass = blobs.mass();
-
-    if (biggestBlob.mass() > totalMass/2) {
-        if (biggestBlob instanceof Object(PlayerBlob)) {
-            return this.win();
-        } else {
-            return this.lose();
-        }
-    }
-
-    return this;
-}
-
-GameState.prototype.isWinningPossible = function(player, blobs) {
-    var biggerBlobs = blobs.filter(function(b) {
-        return b !== player && player.mass() < b.mass();
-    });
-    var smallerBlobs = blobs.filter(function(b) {
-        return b !== player && player.mass() >= b.mass();
-    });
-    var smallerMass = smallerBlobs.mass();
-    return biggerBlobs.length === 0 || biggerBlobs.some(function(b) {
-        return smallerMass + player.mass() > b.mass();
-    });
-}
-
-GameState.prototype.lose = function() {
-    return new LosingGameState();
+function GameState(game) {
+    this.game = game;
 }
 
-GameState.prototype.win = function() {
-    return new WinningGameState();
-}
+GameState.prototype.handle = function(input, gametime) {}
 
-GameState.prototype.status = function() {
-    return "Running...";
-}
+GameState.prototype.status = function() {}
 
-GameState.prototype.isRunning = function() {
-    return true;
-}

src/LosingGameState.js

@@ -14,20 +14,17 @@
  * limitations under the License.
  */
 
-var LosingGameState = function() {
-    GameState.call(this);
+var LosingGameState = function(game) {
+    GameState.call(this, game);
 }
 
 LosingGameState.prototype = new GameState();
 
-LosingGameState.prototype.transition = function(blobs) {
+LosingGameState.prototype.handle = function(input, gametime) {
     return this;
 }
 
 LosingGameState.prototype.status = function() {
     return "Lost!";
 }
 
-LosingGameState.prototype.isRunning = function() {
-    return false;
-}

src/RunningGameState.js

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2011, 2012 Christoph Thelen
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+var RunningGameState = function(game) {
+    GameState.call(this, game);
+}
+
+RunningGameState.prototype = new GameState();
+
+RunningGameState.prototype.handle = function(input, gametime) {
+    var blobs = this.game.blobs;
+
+    if (blobs.length === 0) {
+        return new LosingGameState();
+    }
+    var playerBlobs = blobs.filter(function(b) {
+        return b.player > 0;
+    });
+    if (playerBlobs.length === 0) {
+        return new LosingGameState(this.game);
+    }
+    // For now, we assume only one player...
+    var playerBlob = playerBlobs.shift();
+    if (!this.isWinningPossible(playerBlob, blobs)) {
+        return new LosingGameState(this.game);
+    }
+
+    var biggestBlob = blobs.reduce(function(a, b) {
+        return a.mass() > b.mass() ? a : b;
+    });
+    var totalMass = blobs.mass();
+
+    if (biggestBlob.mass() > totalMass/2) {
+        if (biggestBlob instanceof Object(PlayerBlob)) {
+            return new WinningGameState(this.game);
+        } else {
+            return new LosingGameState(this.game);
+        }
+    }
+
+    return new RunningGameState(this.game.advance(input, gametime));
+}
+
+RunningGameState.prototype.isWinningPossible = function(player, blobs) {
+    var biggerBlobs = blobs.filter(function(b) {
+        return b !== player && player.mass() < b.mass();
+    });
+    var smallerBlobs = blobs.filter(function(b) {
+        return b !== player && player.mass() >= b.mass();
+    });
+    var smallerMass = smallerBlobs.mass();
+    return biggerBlobs.length === 0 || biggerBlobs.some(function(b) {
+        return smallerMass + player.mass() > b.mass();
+    });
+}
+
+RunningGameState.prototype.status = function() {
+    return "Running...";
+}
+

src/WinningGameState.js

@@ -14,20 +14,17 @@
  * limitations under the License.
  */
 
-var WinningGameState = function() {
-    GameState.call(this);
+var WinningGameState = function(game) {
+    GameState.call(this, game);
 }
 
 WinningGameState.prototype = new GameState();
 
-WinningGameState.prototype.transition = function(blobs) {
+WinningGameState.prototype.handle = function(input, gametime) {
     return this;
 }
 
 WinningGameState.prototype.status = function() {
     return "Won!";
 }
 
-WinningGameState.prototype.isRunning = function() {
-    return false;
-}

src/main.js

@@ -30,12 +30,12 @@ exports.gameLoop = function(canvas) {
         new Blob(new Position(540, 200), new Velocity(5, 0), 40)
     ];
     var bounds = new BouncyBounds(0, 0, 640, 480);
-    var world  = new Game(blobs, bounds, new MassTransformationCollision(), new GameState());
+    var world  = new RunningGameState(new Game(blobs, bounds, new MassTransformationCollision()));
 
     return setInterval(function() {
         var input = new InputHandler(InputQueue.slice());
         InputQueue = [];
-        world = world.advance(input, gametime);
+        world = world.handle(input, gametime);
         draw(world, canvas);
     }, 1000/fps);
 }
@@ -56,8 +56,8 @@ function draw(world, canvas) {
     ctx.textBaseline = "top";
     ctx.fillText(world.status(), 0, 0);
 
-    for (var i = 0; i < world.blobs.length; i++) {
-        var blob = world.blobs[i];
+    for (var i = 0; i < world.game.blobs.length; i++) {
+        var blob = world.game.blobs[i];
 
         ctx.beginPath();
         ctx.arc(blob.position.x, blob.position.y, blob.radius, 0, Math.PI*2, false);

test/GameTest.js

@@ -26,7 +26,7 @@ GameTest.prototype.testShouldReturnNewBlobs = function() {
     var blob2 = new SpyBlob();
 
     var spyCollision = new SpyCollision();
-    var oldWorld = new Game([blob1, blob2], null, spyCollision, new StubGameState);
+    var oldWorld = new Game([blob1, blob2], null, spyCollision);
     var newWorld = oldWorld.advance(this.inputHandler);
 
     assertEquals([blob1.state, blob2.state], newWorld.blobs);
@@ -37,7 +37,7 @@ GameTest.prototype.testShouldInitiateCollisionCheck = function() {
     var blob2 = new Blob(P(), V(), 0);
 
     var spyCollision = new SpyCollision();
-    var oldWorld = new Game([blob1, blob2], this.bounds, spyCollision, new StubGameState);
+    var oldWorld = new Game([blob1, blob2], this.bounds, spyCollision);
     oldWorld.advance(this.inputHandler, new GameTime(1, 1));
 
     assertTrue(spyCollision.called);
@@ -47,29 +47,12 @@ GameTest.prototype.testShouldRemoveMasslessBlobs = function() {
     var blob1 = new Blob(P(), V(), 0);
     var blob2 = new Blob(P(), V(), 0);
 
-    var oldWorld = new Game([blob1, blob2], this.bounds, new SpyCollision(), new StubGameState);
+    var oldWorld = new Game([blob1, blob2], this.bounds, new SpyCollision());
     var newWorld = oldWorld.advance(this.inputHandler, new GameTime(1, 1));
 
     assertEquals([], newWorld.blobs);
 }
 
-GameTest.prototype.testShouldTransitionState = function() {
-    var spyGameState = new SpyGameState();
-    var world = new Game([], this.bounds, new SpyCollision(), spyGameState);
-    world.advance(this.inputHandler, new GameTime(1, 1));
-
-    assertTrue(spyGameState.called);
-}
-
-GameTest.prototype.testShouldStopPlayingIfGameIsNotInRunningState = function() {
-    var spyCollision = new SpyCollision();
-    var stubGameState = new StubGameState(false);
-    var world = new Game([], this.bounds, spyCollision, stubGameState);
-    world.advance(this.inputHandler, new GameTime(1, 1));
-
-    assertFalse(spyCollision.called);
-}
-
 var SpyBlob = function() {
     this.state = {};
 }
@@ -88,13 +71,3 @@ SpyCollision.prototype.perform = function(blobs) {
     return blobs;
 }
 
-var SpyGameState = function() {
-    this.called = false;
-    this.isRunning = function () { return true; }
-    this.transition = function (blobs) { this.called = true; return this; };
-}
-
-var StubGameState = function(running) {
-    this.isRunning = function () { return typeof running === "undefined" ? true : false; }
-    this.transition = function (blobs) { return this; }
-}