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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
#
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"""A simple web server for testing purpose.
It serves the testing html pages that are needed by the webdriver unit tests."""

import logging
import os
import socket
import threading
from io import open
try:
    from urllib import request as urllib_request
except ImportError:
    import urllib as urllib_request
try:
    from http.server import BaseHTTPRequestHandler, HTTPServer
    from socketserver import ThreadingMixIn
except ImportError:
    from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
    from SocketServer import ThreadingMixIn


def updir():
    dirname = os.path.dirname
    return dirname(dirname(__file__))


LOGGER = logging.getLogger(__name__)
WEBDRIVER = os.environ.get("WEBDRIVER", updir())
HTML_ROOT = os.path.join(WEBDRIVER, "../../../../common/src/web")
if not os.path.isdir(HTML_ROOT):
    message = ("Can't find 'common_web' directory, try setting WEBDRIVER"
               " environment variable WEBDRIVER:" + WEBDRIVER + "  HTML_ROOT:" + HTML_ROOT)
    LOGGER.error(message)
    assert 0, message

DEFAULT_HOST = "127.0.0.1"
DEFAULT_PORT = 8000


class HtmlOnlyHandler(BaseHTTPRequestHandler):
    """Http handler."""
    def do_GET(self):
        """GET method handler."""
        try:
            path = self.path[1:].split('?')[0]
            if path[:5] == "page/":
                html = """<html><head><title>Page{page_number}</title></head>
                <body>Page number <span id=\"pageNumber\">{page_number}</span>
                <p><a href=\"../xhtmlTest.html\" target=\"_top\">top</a>
                </body></html>""".format(page_number=path[5:])
                html = html.encode('utf-8')
            else:
                with open(os.path.join(HTML_ROOT, path), 'r', encoding='latin-1') as f:
                    html = f.read().encode('utf-8')
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write(html)
        except IOError:
            self.send_error(404, 'File Not Found: %s' % path)

    def log_message(self, format, *args):
        """Override default to avoid trashing stderr"""
        pass


class ThreadedHTTPServer(ThreadingMixIn, HTTPServer):
    pass


class SimpleWebServer(object):
    """A very basic web server."""
    def __init__(self, host=DEFAULT_HOST, port=DEFAULT_PORT):
        self.stop_serving = False
        host = host
        port = port
        while True:
            try:
                self.server = ThreadedHTTPServer((host, port), HtmlOnlyHandler)
                self.host = host
                self.port = port
                break
            except socket.error:
                LOGGER.debug("port %d is in use, trying to next one" % port)
                port += 1

        self.thread = threading.Thread(target=self._run_web_server)

    def _run_web_server(self):
        """Runs the server loop."""
        LOGGER.debug("web server started")
        while not self.stop_serving:
            self.server.handle_request()
        self.server.server_close()

    def start(self):
        """Starts the server."""
        self.thread.start()

    def stop(self):
        """Stops the server."""
        self.stop_serving = True
        try:
            # This is to force stop the server loop
            urllib_request.URLopener().open("http://%s:%d" % (self.host, self.port))
        except IOError:
            pass
        LOGGER.info("Shutting down the webserver")
        self.thread.join()

    def where_is(self, path):
        return "http://%s:%d/%s" % (self.host, self.port, path)


def main(argv=None):
    from optparse import OptionParser
    from time import sleep

    if argv is None:
        import sys
        argv = sys.argv

    parser = OptionParser("%prog [options]")
    parser.add_option("-p", "--port", dest="port", type="int",
                      help="port to listen (default: %s)" % DEFAULT_PORT,
                      default=DEFAULT_PORT)

    opts, args = parser.parse_args(argv[1:])
    if args:
        parser.error("wrong number of arguments")  # Will exit

    server = SimpleWebServer(opts.port)
    server.start()
    print("Server started on port %s, hit CTRL-C to quit" % opts.port)
    try:
        while 1:
            sleep(0.1)
    except KeyboardInterrupt:
        pass


if __name__ == "__main__":
    main()
