ch.rasc.s4ws.snake.SnakeWebSocketHandler.java Source code

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Here is the source code for ch.rasc.s4ws.snake.SnakeWebSocketHandler.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
package ch.rasc.s4ws.snake;

import java.awt.Color;
import java.util.Iterator;
import java.util.Random;
import java.util.concurrent.atomic.AtomicInteger;

import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.TextWebSocketHandler;

public class SnakeWebSocketHandler extends TextWebSocketHandler {

    public static final int PLAYFIELD_WIDTH = 640;

    public static final int PLAYFIELD_HEIGHT = 480;

    public static final int GRID_SIZE = 10;

    private static final AtomicInteger snakeIds = new AtomicInteger(0);

    private static final Random random = new Random();

    private final int id;

    private Snake snake;

    public static String getRandomHexColor() {
        float hue = random.nextFloat();
        // sat between 0.1 and 0.3
        float saturation = (random.nextInt(2000) + 1000) / 10000f;
        float luminance = 0.9f;
        Color color = Color.getHSBColor(hue, saturation, luminance);
        return '#' + Integer.toHexString(color.getRGB() & 0xffffff | 0x1000000).substring(1);
    }

    public static Location getRandomLocation() {
        int x = roundByGridSize(random.nextInt(PLAYFIELD_WIDTH));
        int y = roundByGridSize(random.nextInt(PLAYFIELD_HEIGHT));
        return new Location(x, y);
    }

    private static int roundByGridSize(int value) {
        int newValue = value + GRID_SIZE / 2;
        newValue = newValue / GRID_SIZE;
        newValue = newValue * GRID_SIZE;
        return newValue;
    }

    public SnakeWebSocketHandler() {
        this.id = snakeIds.getAndIncrement();
    }

    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        this.snake = new Snake(this.id, session);
        SnakeTimer.addSnake(this.snake);
        StringBuilder sb = new StringBuilder();
        for (Iterator<Snake> iterator = SnakeTimer.getSnakes().iterator(); iterator.hasNext();) {
            Snake otherSnake = iterator.next();
            sb.append(String.format("{\"id\": %d, \"color\": \"%s\"}", Integer.valueOf(otherSnake.getId()),
                    otherSnake.getHexColor()));
            if (iterator.hasNext()) {
                sb.append(',');
            }
        }
        SnakeTimer.broadcast(String.format("{\"type\": \"join\",\"data\":[%s]}", sb.toString()));
    }

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        String payload = message.getPayload();
        if ("west".equals(payload)) {
            this.snake.setDirection(Direction.WEST);
        } else if ("north".equals(payload)) {
            this.snake.setDirection(Direction.NORTH);
        } else if ("east".equals(payload)) {
            this.snake.setDirection(Direction.EAST);
        } else if ("south".equals(payload)) {
            this.snake.setDirection(Direction.SOUTH);
        }
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
        SnakeTimer.removeSnake(this.snake);
        SnakeTimer.broadcast(String.format("{'type': 'leave', 'id': %d}", Integer.valueOf(this.id)));
    }
}