content: /**
   * 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 org.apache.activemq.web;
  
  import java.io.IOException;
  import java.io.PrintWriter;
  import java.util.Hashtable;
  import java.util.Map;
  
  import jakarta.jms.Destination;
  import jakarta.jms.JMSException;
  import jakarta.jms.Message;
  import jakarta.jms.Session;
  import jakarta.servlet.ServletException;
  import jakarta.servlet.http.HttpServletRequest;
  import jakarta.servlet.http.HttpServletResponse;
  
  /**
   * A servlet which will publish dummy market data prices
   * 
   * 
   */
  public class PortfolioPublishServlet extends MessageServletSupport {
  
      private static final int MAX_DELTA_PERCENT = 1;
      private static final Map<String, Double> LAST_PRICES = new Hashtable<String, Double>();
  
      public void init() throws ServletException {
          super.init();
      }
  
      protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
          PrintWriter out = response.getWriter();
          String[] stocks = request.getParameterValues("stocks");
          if (stocks == null || stocks.length == 0) {
              out.println("<html><body>No <b>stocks</b> query parameter specified. Cannot publish market data</body></html>");
          } else {
              Integer total = (Integer)request.getSession(true).getAttribute("total");
              if (total == null) {
                  total = 0;
              }
  
              int count = getNumberOfMessages(request);
              total = total + count;
              request.getSession().setAttribute("total", total);
  
              try {
                  WebClient client = WebClient.getWebClient(request);
                  for (int i = 0; i < count; i++) {
                      sendMessage(client, stocks);
                  }
                  out.print("<html><head><meta http-equiv='refresh' content='");
                  String refreshRate = request.getParameter("refresh");
                  if (refreshRate == null || refreshRate.length() == 0) {
                      refreshRate = "1";
                  }
                  out.print(escape(refreshRate));
                  out.println("'/></head>");
                  out.println("<body>Published <b>" + escape(Integer.toString(count)) + "</b> of " + escape(Integer.toString(total))
                          + " price messages.  Refresh = " + escape(refreshRate) + "s");
                  out.println("</body></html>");
  
              } catch (JMSException e) {
                  out.println("<html><body>Failed sending price messages due to <b>" + e + "</b></body></html>");
                  log("Failed to send message: " + e, e);
              }
          }
      }
  
      protected void sendMessage(WebClient client, String[] stocks) throws JMSException {
          Session session = client.getSession();
  
          int idx = 0;
          while (true) {
              idx = (int)Math.round(stocks.length * Math.random());
              if (idx < stocks.length) {
                  break;
              }
          }
          String stock = stocks[idx];
          Destination destination = session.createTopic("STOCKS." + stock);
          String stockText = createStockText(stock);
          log("Sending: " + stockText + " on destination: " + destination);
          Message message = session.createTextMessage(stockText);
          client.send(destination, message);
      }
  
      protected String createStockText(String stock) {
          Double value = LAST_PRICES.get(stock);
          if (value == null) {
              value = Math.random() * 100;
          }
  
          // lets mutate the value by some percentage
          double oldPrice = value;
          value = mutatePrice(oldPrice);
          LAST_PRICES.put(stock, value);
          double price = value;
  
          double offer = price * 1.001;
  
          String movement = (price > oldPrice) ? "up" : "down";
          return "<price stock='" + stock + "' bid='" + price + "' offer='" + offer + "' movement='" + movement + "'/>";
      }
  
      protected double mutatePrice(double price) {
          double percentChange = (2 * Math.random() * MAX_DELTA_PERCENT) - MAX_DELTA_PERCENT;
  
          return price * (100 + percentChange) / 100;
      }
  
      protected int getNumberOfMessages(HttpServletRequest request) {
          String name = request.getParameter("count");
          if (name != null) {
              return Integer.parseInt(name);
          }
          return 1;
      }
  
      protected String escape(String text) throws IOException {
          return java.net.URLEncoder.encode(text, "UTF-8");
      }
  }
  