/**

 * 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;

        }

    }

}