/*

 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jaxp.library;

import com.sun.net.httpserver.Headers;

import com.sun.net.httpserver.HttpContext;

import com.sun.net.httpserver.HttpExchange;

import com.sun.net.httpserver.HttpHandler;

import com.sun.net.httpserver.HttpServer;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.InetSocketAddress;

import java.net.URI;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

/**

 * A simple HTTP Server

 */

public class SimpleHttpServer {

    HttpServer _httpserver;

    ExecutorService _executor;

    String _address;

    String _context, _docroot;

    int _port;

    public SimpleHttpServer(String context, String docroot) {

        //let the system pick up an ephemeral port in a bind operation

        this(0, context, docroot);

    }

    public SimpleHttpServer(int port, String context, String docroot) {

        _port = port;

        _context = context;

        _docroot = docroot;

    }

    public void start() {

        MyHttpHandler handler = new MyHttpHandler(_docroot);

        InetSocketAddress addr = new InetSocketAddress(_port);

        try {

            _httpserver = HttpServer.create(addr, 0);

        } catch (IOException ex) {

            throw new RuntimeException("cannot create httpserver", ex);

        }

        //TestHandler is mapped to /test

        HttpContext ctx = _httpserver.createContext(_context, handler);

        _executor = Executors.newCachedThreadPool();

        _httpserver.setExecutor(_executor);

        _httpserver.start();

        _address = "http://localhost:" + _httpserver.getAddress().getPort();

    }

    public void stop() {

        _httpserver.stop(2);

        _executor.shutdown();

    }

    public String getAddress() {

        return _address;

    }

    static class MyHttpHandler implements HttpHandler {

        String _docroot;

        public MyHttpHandler(String docroot) {

            _docroot = docroot;

        }

        public void handle(HttpExchange t)

                throws IOException {

            InputStream is = t.getRequestBody();

            Headers map = t.getRequestHeaders();

            Headers rmap = t.getResponseHeaders();

            OutputStream os = t.getResponseBody();

            URI uri = t.getRequestURI();

            String path = uri.getPath();

            while (is.read() != -1) ;

            is.close();

            File f = new File(_docroot, path);

            if (!f.exists()) {

                notfound(t, path);

                return;

            }

            String method = t.getRequestMethod();

            if (method.equals("HEAD")) {

                rmap.set("Content-Length", Long.toString(f.length()));

                t.sendResponseHeaders(200, -1);

                t.close();

            } else if (!method.equals("GET")) {

                t.sendResponseHeaders(405, -1);

                t.close();

                return;

            }

            if (path.endsWith(".html") || path.endsWith(".htm")) {

                rmap.set("Content-Type", "text/html");

            } else {

                rmap.set("Content-Type", "text/plain");

            }

            t.sendResponseHeaders (200, f.length());

            FileInputStream fis = new FileInputStream(f);

            int count = 0;

            try {

                byte[] buf = new byte[16 * 1024];

                int len;

                while ((len = fis.read(buf)) != -1) {

                    os.write(buf, 0, len);

                    count += len;

                }

            } catch (IOException e) {

                e.printStackTrace();

            }

            fis.close();

            os.close();

        }

        void moved(HttpExchange t) throws IOException {

            Headers req = t.getRequestHeaders();

            Headers map = t.getResponseHeaders();

            URI uri = t.getRequestURI();

            String host = req.getFirst("Host");

            String location = "http://" + host + uri.getPath() + "/";

            map.set("Content-Type", "text/html");

            map.set("Location", location);

            t.sendResponseHeaders(301, -1);

            t.close();

        }

        void notfound(HttpExchange t, String p) throws IOException {

            t.getResponseHeaders().set("Content-Type", "text/html");

            t.sendResponseHeaders(404, 0);

            OutputStream os = t.getResponseBody();

            String s = "<h2>File not found</h2>";

            s = s + p + "<p>";

            os.write(s.getBytes());

            os.close();

            t.close();

        }

    }

}