/**

  * 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.launcher;

 import java.awt.Desktop;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStream;

 import java.io.Writer;

 import java.net.URI;

 import java.net.URL;

 import java.util.Enumeration;

 import java.util.concurrent.CountDownLatch;

 import static org.apidesign.bck2brwsr.launcher.Bck2BrwsrLauncher.copyStream;

 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 Bck2Brwsr applications in real browser.

  */

 public class Bck2BrwsrLauncher {

     public static void main( String[] args ) throws Exception {

         final Case[] cases = { 

             new Case("org.apidesign.bck2brwsr.launcher.Console", "welcome"),

             new Case("org.apidesign.bck2brwsr.launcher.Console", "multiply")

         };

         final CountDownLatch wait = new CountDownLatch(1);

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

         final ClassLoader loader = Bck2BrwsrLauncher.class.getClassLoader();

         final ServerConfiguration conf = server.getServerConfiguration();

         conf.addHttpHandler(new Page("console.xhtml", 

             "org.apidesign.bck2brwsr.launcher.Console", "welcome", "false"

         ), "/console");

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

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

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

         conf.addHttpHandler(new HttpHandler() {

             @Override

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

                 String clazz = request.getParameter("class");

                 String method = request.getParameter("method");

                 if (clazz == null || method == null) {

                     response.setError();

                     response.setDetailMessage("Need two parameters: class and method name!");

                     return;

                 }

                 response.setContentType("text/html");

                 OutputStream os = response.getOutputStream();

                 InputStream is = Bck2BrwsrLauncher.class.getResourceAsStream("console.xhtml");

                 copyStream(is, os, clazz, method, "true");

             }

         }, "/");

         conf.addHttpHandler(new HttpHandler() {

             int cnt;

             @Override

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

                 String id = request.getParameter("request");

                 String value = request.getParameter("result");

                 if (id != null && value != null) {

                     value = value.replace("%20", " ");

                     cases[Integer.parseInt(id)].result = value;

                 }

                 if (cnt >= cases.length) {

                     response.getWriter().write("");

                     wait.countDown();

                     cnt = 0;

                     return;

                 }

                 response.getWriter().write("{"

                     + "className: '" + cases[cnt].className + "', "

                     + "methodName: '" + cases[cnt].methodName + "', "

                     + "request: " + cnt

                     + "}");

                 cnt++;

             }

         }, "/data");

         conf.addHttpHandler(new Page("harness.xhtml"), "/execute");

         server.start();

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

         int port = listener.getPort();

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

         try {

             Desktop.getDesktop().browse(uri);

         } catch (UnsupportedOperationException ex) {

             String[] cmd = { 

                 "xdg-open", uri.toString()

             };

             Runtime.getRuntime().exec(cmd).waitFor();

         }

         wait.await();

         for (Case c : cases) {

             System.err.println(c.className + "." + c.methodName + " = " + c.result);

         }

     }

     static void copyStream(InputStream is, OutputStream os, String baseURL, String... params) throws IOException {

         for (;;) {

             int ch = is.read();

             if (ch == -1) {

                 break;

             }

             if (ch == '$') {

                 int cnt = is.read() - '0';

                 if (cnt == 'U' - '0') {

                     os.write(baseURL.getBytes());

                 }

                 if (cnt < params.length) {

                     os.write(params[cnt].getBytes());

                 }

             } else {

                 os.write(ch);

             }

         }

     }

     private static class Page extends HttpHandler {

         private final String resource;

         private final String[] args;

         public Page(String resource, String... args) {

             this.resource = resource;

             this.args = args;

         }

         @Override

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

             response.setContentType("text/html");

             OutputStream os = response.getOutputStream();

             InputStream is = Bck2BrwsrLauncher.class.getResourceAsStream(resource);

             copyStream(is, os, request.getRequestURL().toString(), args);

         }

     }

     private static class VM extends HttpHandler {

         private final ClassLoader loader;

         public VM(ClassLoader loader) {

             this.loader = loader;

         }

         @Override

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

             response.setCharacterEncoding("UTF-8");

             response.setContentType("text/javascript");

             Bck2Brwsr.generate(response.getWriter(), loader);

         }

     }

     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 ClassLoader loader;

         public Classes(ClassLoader 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);

             }

             Enumeration<URL> en = loader.getResources(res);

             URL u = null;

             while (en.hasMoreElements()) {

                 u = en.nextElement();

             }

             if (u == null) {

                 response.setError();

                 response.setDetailMessage("Can't find resource " + res);

             }

             response.setContentType("text/javascript");

             InputStream is = u.openStream();

             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]");

         }

     }

     private static final class Case {

         final String className;

         final String methodName;

         String result;

         public Case(String className, String methodName) {

             this.className = className;

             this.methodName = methodName;

         }

     }

 }