import os

from dispatcher import Dispatcher
from paste.httpexceptions import HTTPExceptionHandler
from paste.urlparser import StaticURLParser
from pkg_resources import resource_filename

class PassthroughFileserver(object):
    """serve files if they exist"""

    def __init__(self, app, directory):
        self.app = app
        self.directory = directory
        self.fileserver = StaticURLParser(directory)

    def __call__(self, environ, start_response):
        path = self.path(environ['PATH_INFO'].strip('/'))
        if path and os.path.exists(os.path.join(self.directory, path)):
            return self.fileserver(environ, start_response)
        return self.app(environ, start_response)

class NamespacedFileserver(PassthroughFileserver):

    def __init__(self, app, directory, namespace):
        PassthroughFileserver.__init__(self, app, directory)
        self.namespace = namespace

    def __call__(self, environ, start_response):
        path = environ['PATH_INFO']
        if path == self.namespace:
            environ['PATH_INFO'] = '/'
            return self.fileserver(environ, start_response)
        elif path.startswith(self.namespace + '/'):
            environ['PATH_INFO'] = path[len(self.namespace):]
            return self.fileserver(environ, start_response)
        return self.app(environ, start_response)

def factory(**app_conf):
    """create a webob view and wrap it in middleware"""
    directory = app_conf['directory']
    app = Dispatcher(**app_conf)
    # TODO: something about serving simple_index, etc
    return PassthroughFileserver(app, resource_filename(__name__, 'static'))

if __name__ == '__main__':
    import shutil
    import tempfile
    from wsgiref import simple_server
    port = 8080
    print "http://localhost:%d/" % port
    tempdir = tempfile.mkdtemp()
    try:
        app = factory(directory=tempdir)
        server = simple_server.make_server(host='0.0.0.0', port=port, app=app)
        server.serve_forever()
    finally:
        shutil.rmtree(tempdir)