/**

  * Back 2 Browser Bytecode Translator

  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>

  *

  * This program is free software: you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation, version 2 of the License.

  *

  * This program is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  * GNU General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License

  * along with this program. Look for COPYING file in the top folder.

  * If not, see http://opensource.org/licenses/GPL-2.0.

  */

 package org.apidesign.bck2brwsr.dew;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.Writer;

 import java.net.URI;

 import java.net.URISyntaxException;

 import java.net.URL;

 import java.util.Arrays;

 import java.util.Enumeration;

 import java.util.LinkedHashSet;

 import java.util.Set;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import org.apidesign.vm4brwsr.Bck2Brwsr;

 import org.glassfish.grizzly.PortRange;

 import org.glassfish.grizzly.http.server.HttpHandler;

 import org.glassfish.grizzly.http.server.HttpServer;

 import org.glassfish.grizzly.http.server.NetworkListener;

 import org.glassfish.grizzly.http.server.Request;

 import org.glassfish.grizzly.http.server.Response;

 import org.glassfish.grizzly.http.server.ServerConfiguration;

 /**

  * Lightweight server to launch dew - the Development Environment for Web.

  */

 final class DewLauncher {

     private static final Logger LOG = Logger.getLogger(DewLauncher.class.getName());

     private Set<ClassLoader> loaders = new LinkedHashSet<>();

     private Set<Bck2Brwsr.Resources> xRes = new LinkedHashSet<>();

     private final Res resources = new Res();

     private final String cmd;

     public DewLauncher(String cmd) {

         this.cmd = cmd;

     }

     public void addClassLoader(ClassLoader url) {

         this.loaders.add(url);

     }

     final HttpServer initServer(Bck2Brwsr.Resources... extraResources) throws IOException {

         xRes.addAll(Arrays.asList(extraResources));

         HttpServer s = HttpServer.createSimpleServer(".", new PortRange(8080, 65535));

         final ServerConfiguration conf = s.getServerConfiguration();

         conf.addHttpHandler(new VM(resources), "/bck2brwsr.js");

         conf.addHttpHandler(new VMInit(), "/vm.js");

         conf.addHttpHandler(new Classes(resources), "/classes/");

         return s;

     }

     final Object[] launchServerAndBrwsr(HttpServer server, final String page) throws IOException, URISyntaxException, InterruptedException {

         server.start();

         NetworkListener listener = server.getListeners().iterator().next();

         int port = listener.getPort();

         URI uri = new URI("http://localhost:" + port + page);

         LOG.log(Level.INFO, "Showing {0}", uri);

         if (cmd == null) {

             try {

                 LOG.log(Level.INFO, "Trying Desktop.browse on {0} {2} by {1}", new Object[] {

                     System.getProperty("java.vm.name"),

                     System.getProperty("java.vm.vendor"),

                     System.getProperty("java.vm.version"),

                 });

                 java.awt.Desktop.getDesktop().browse(uri);

                 LOG.log(Level.INFO, "Desktop.browse successfully finished");

                 return null;

             } catch (UnsupportedOperationException ex) {

                 LOG.log(Level.INFO, "Desktop.browse not supported: {0}", ex.getMessage());

                 LOG.log(Level.FINE, null, ex);

             }

         }

         {

             String cmdName = cmd == null ? "xdg-open" : cmd;

             String[] cmdArr = { 

                 cmdName, uri.toString()

             };

             LOG.log(Level.INFO, "Launching {0}", Arrays.toString(cmdArr));

             final Process process = Runtime.getRuntime().exec(cmdArr);

             return new Object[] { process, null };

         }

     }

     private class Res implements Bck2Brwsr.Resources {

         @Override

         public InputStream get(String resource) throws IOException {

             for (ClassLoader l : loaders) {

                 URL u = null;

                 Enumeration<URL> en = l.getResources(resource);

                 while (en.hasMoreElements()) {

                     u = en.nextElement();

                 }

                 if (u != null) {

                     return u.openStream();

                 }

             }

             for (Bck2Brwsr.Resources r : xRes) {

                 InputStream is = r.get(resource);

                 if (is != null) {

                     return is;

                 }

             }

             throw new IOException("Can't find " + resource);

         }

         @Override

         public String getModule(String resource) throws IOException {

             return null;

         }

     }

     private static class VM extends HttpHandler {

         private final String bck2brwsr;

         public VM(Res loader) throws IOException {

             StringBuilder sb = new StringBuilder();

             Bck2Brwsr.generate(sb, loader);

             this.bck2brwsr = sb.toString();

         }

         @Override

         public void service(Request request, Response response) throws Exception {

             response.setCharacterEncoding("UTF-8");

             response.setContentType("text/javascript");

             response.getWriter().write(bck2brwsr);

         }

     }

     private static class VMInit extends HttpHandler {

         public VMInit() {

         }

         @Override

         public void service(Request request, Response response) throws Exception {

             response.setCharacterEncoding("UTF-8");

             response.setContentType("text/javascript");

             response.getWriter().append(

                 "function ldCls(res) {\n"

                 + "  var request = new XMLHttpRequest();\n"

                 + "  request.open('GET', '/classes/' + res, false);\n"

                 + "  request.send();\n"

                 + "  var arr = eval('(' + request.responseText + ')');\n"

                 + "  return arr;\n"

                 + "}\n"

                 + "var vm = new bck2brwsr(ldCls);\n");

         }

     }

     private static class Classes extends HttpHandler {

         private final Res loader;

         public Classes(Res loader) {

             this.loader = loader;

         }

         @Override

         public void service(Request request, Response response) throws Exception {

             String res = request.getHttpHandlerPath();

             if (res.startsWith("/")) {

                 res = res.substring(1);

             }

             try (InputStream is = loader.get(res)) {

                 response.setContentType("text/javascript");

                 Writer w = response.getWriter();

                 w.append("[");

                 for (int i = 0;; i++) {

                     int b = is.read();

                     if (b == -1) {

                         break;

                     }

                     if (i > 0) {

                         w.append(", ");

                     }

                     if (i % 20 == 0) {

                         w.write("\n");

                     }

                     if (b > 127) {

                         b = b - 256;

                     }

                     w.append(Integer.toString(b));

                 }

                 w.append("\n]");

             } catch (IOException ex) {

                 response.setError();

                 response.setDetailMessage(ex.getMessage());

             }

         }

     }

 }