from django.core.management.base import BaseCommand, CommandError
import os
import sys

class Command(BaseCommand):
    help = "Starts a lightweight Web server for development."
    args = '[--noreload] [--adminmedia=ADMIN_MEDIA_PATH] [optional port number, or ipaddr:port]'

    # Validation is called explicitly each time the server is reloaded.
    requires_model_validation = False

    def handle(self, addrport='', *args, **options):
        import django
        from django.core.servers.basehttp import run, AdminMediaHandler, WSGIServerException
        from django.core.handlers.wsgi import WSGIHandler
        if len(args) != 0:
            raise CommandError('Usage is runserver %s' % self.args)
        if not addrport:
            addr = ''
            port = '8000'
        else:
            try:
                addr, port = addrport.split(':')
            except ValueError:
                addr, port = '', addrport
        if not addr:
            addr = '127.0.0.1'

        if not port.isdigit():
            raise CommandError("%r is not a valid port number." % port)

        use_reloader = options.get('use_reloader', True)
        admin_media_dir = options.get('admin_media_dir', '')
        shutdown_message = options.get('shutdown_message', '')
        quit_command = (sys.platform == 'win32') and 'CTRL-BREAK' or 'CONTROL-C'

        def inner_run():
            from django.conf import settings
            print "Validating models..."
            self.validate()
            print "\nDjango version %s, using settings %r" % (django.get_version(), settings.SETTINGS_MODULE)
            print "Development server is running at http://%s:%s/" % (addr, port)
            print "Quit the server with %s." % quit_command
            try:
                path = admin_media_dir or django.__path__[0] + '/contrib/admin/media'
                handler = AdminMediaHandler(WSGIHandler(), path)
                run(addr, int(port), handler)
            except WSGIServerException, e:
                # Use helpful error messages instead of ugly tracebacks.
                ERRORS = {
                    13: "You don't have permission to access that port.",
                    98: "That port is already in use.",
                    99: "That IP address can't be assigned-to.",
                }
                try:
                    error_text = ERRORS[e.args[0].args[0]]
                except (AttributeError, KeyError):
                    error_text = str(e)
                sys.stderr.write(self.style.ERROR("Error: %s" % error_text) + '\n')
                # Need to use an OS exit because sys.exit doesn't work in a thread
                os._exit(1)
            except KeyboardInterrupt:
                if shutdown_message:
                    print shutdown_message
                sys.exit(0)
        if use_reloader:
            from django.utils import autoreload
            autoreload.main(inner_run)
        else:
            inner_run()