#!/usr/local/bin/python

import sys

from BaseHTTPServer import BaseHTTPRequestHandler

from ZSI import Fault, ParseException, FaultFromNotUnderstood, \
    FaultFromZSIException, FaultFromException, ParsedSoap, SoapWriter

from M2Crypto import SSL
from M2Crypto.SSL.SSLServer import ThreadingSSLServer
import xmlrpclib

from deter import fedid

# ZSI uses a deprecated multifile interface.  This shuts the warning system up.
from warnings import filterwarnings
filterwarnings("ignore", ".*multifile.*", DeprecationWarning, "ZSI")

try:
    from fedd_services import ns0
except ImportError:
    from fedd_server import ns0

from service_error import *

import os.path

import logging
import traceback

# The SSL server here is based on the implementation described at
# http://www.xml.com/pub/a/ws/2004/01/20/salz.html

# Turn off the matching of hostname to certificate ID
SSL.Connection.clientPostConnectionCheck = None

class server(ThreadingSSLServer):
    """
    Interface the fedd services to the XMLRPC and SOAP interfaces
    """
    def __init__(self, ME, handler, ssl_ctx, impl, debug=False):
	"""
	Create an SSL server that handles the transport in handler using the
	credentials in ssl_ctx, and interfacing to the implementation of fedd
	services in fedd.  ME is the host port pair on which to bind.
	"""
	ThreadingSSLServer.__init__(self, ME, handler, ssl_ctx)
	self.impl = impl
	self.soap_methods = impl.soap_services
	self.xmlrpc_methods = impl.xmlrpc_services
	self.get_handler = impl.get_handler
	self.log = logging.getLogger("fedd")
	if debug: self.handle_error = self.handle_error_debug
	else: self.handle_error = self.handle_error_standard

    def handle_error_debug(self, request=None, client_address=None):
	print '-'*40
	traceback.print_exc()
	print '-'*40


    def handle_error_standard(self, request=None, address=None):
	"""
	The default SSLServer prints a stack trace here.  This is a little
	friendlier.
	"""
	if request or address:
	    self.log.warn("[fedd] Error on incoming connection: %s %s" % \
		    (request or "", address or ""))
	else:
	    self.log.warn("[fedd] Error on incoming connection " + \
		    "(Likely SSL error)")

class soap_handler(BaseHTTPRequestHandler):
    """
    Standard connection between SOAP and the fedd services in impl.

    Much of this is boilerplate from 
    http://www.xml.com/pub/a/ws/2004/01/20/salz.html
    """
    server_version = "ZSI/2.0 fedd/0.1 " + BaseHTTPRequestHandler.server_version

    def send_xml(self, text, code=200):
	"""Send an XML document as reply"""
	self.send_response(code)
	self.send_header('Content-type', 'text/xml; charset="utf-8"')
	self.send_header('Content-Length', str(len(text)))
	self.end_headers()
	self.wfile.write(text)
	self.wfile.flush()
	self.request.socket.close()

    def send_fault(self, f, code=500):
	"""Send a SOAP encoded fault as reply"""
	self.send_xml(f.AsSOAP(processContents="lax"), code)

    def check_headers(self, ps):
	"""Send a fault for any required envelope headers"""
	for (uri, localname) in ps.WhatMustIUnderstand():
	    self.send_fault(FaultFromNotUnderstood(uri, lname, 'fedd'))
	    return False
	return  True

    def check_method(self, ps):
	"""Confirm that this class implements the namespace and SOAP method"""
	root = ps.body_root
	if root.namespaceURI not in self.server.impl.soap_namespaces:
	    self.send_fault(Fault(Fault.Client, 
		'Unknown namespace "%s"' % root.namespaceURI))
	    return False

	if getattr(root, 'localName', None) == None:
	    self.send_fault(Fault(Fault.Client, 'No method"'))
	    return False
	return True

    def do_POST(self):
	"""Treat an HTTP POST request as a SOAP service call"""
	try:
	    cl = int(self.headers['content-length'])
	    data = self.rfile.read(cl)
	    ps = ParsedSoap(data)
	except ParseException, e:
	    self.send_fault(Fault(Fault.Client, str(e)))
	    return
	except Exception, e:
	    self.send_fault(FaultFromException(e, 0, sys.exc_info()[2]))
	    return
	if not self.check_headers(ps): return
	if not self.check_method(ps): return
	try:
	    resp = self.soap_dispatch(ps.body_root.localName, ps,
		    fedid(cert=self.request.get_peer_cert()))
	except Fault, f:
	    self.send_fault(f)
	    resp = None

	if resp != None:
	    sw = SoapWriter()
	    sw.serialize(resp)
	    self.send_xml(str(sw))

    def do_GET(self):
	"""
	If a get handler is registered, use that to retrieve data.
	"""
	if self.server.get_handler:
	    code = 200
	    fid = fedid(cert=self.request.get_peer_cert())
	    fname, type = self.server.get_handler(self.path, fid)
	    if fname:
		try:
		    f = open(fname, "rb")
		    size = os.path.getsize(fname)
		except EnvironmentError, e:
		    code = 404
		    size = 0
	    else:
		code = 404
		size = 0
	else:
	    code = 404
	    size = 0

	self.send_response(code)
	if code == 200:
	    if type:
		self.send_header('Content-type', type)
	    self.send_header('Content-Length', size)
	    self.end_headers()
	    bytes = f.read(4096)
	    while len(bytes):
		self.wfile.write(bytes)
		bytes = f.read(4096)
	    self.wfile.flush()
	self.request.socket.close()


    def log_request(self, code=0, size=0):
	"""
	Log request to the fedd logger
	"""
	self.server.log.info("Successful SOAP request code %d" % code)

    def soap_dispatch(self, method, req, fid):
	"""
	The connection to the implementation, using the  method maps

	The implementation provides a mapping from SOAP method name to the
	method in the implementation that provides the service.
	"""
	if self.server.soap_methods.has_key(method):
	    try:
		return self.server.soap_methods[method](req, fid)
	    except service_error, e:
		de = ns0.faultType_Def(
			(ns0.faultType_Def.schema,
			    "FeddFaultBody")).pyclass()
		de._code=e.code
		de._errstr=e.code_string()
		de._desc=e.desc
		for p in e.proof:
		    dp = ns0.proofType_Def(ns0.proofType_Def.schema, 
			    "proof").pyclass()
		    dp._prover = p.prover
		    dp._principal = p.principal
		    dp._attribute = p.attribute
		    dp._credential = p.creds_to_certs()
		    if de._proof: de._proof.append(dp)
		    else: de._proof = [dp]
		if  e.is_server_error():
		    raise Fault(Fault.Server, e.code_string(), detail=de)
		else:
		    raise Fault(Fault.Client, e.code_string(), detail=de)
	else:
	    raise Fault(Fault.Client, "Unknown method: %s" % method)


class xmlrpc_handler(BaseHTTPRequestHandler):
    """
    Standard connection between XMLRPC and the fedd services in impl.

    Much of this is boilerplate from 
    http://www.xml.com/pub/a/ws/2004/01/20/salz.html
    """
    server_version = "ZSI/2.0 fedd/0.1 " + BaseHTTPRequestHandler.server_version

    def send_xml(self, text, code=200):
	"""Send an XML document as reply"""
	self.send_response(code)
	self.send_header('Content-type', 'text/xml; charset="utf-8"')
	self.send_header('Content-Length', str(len(text)))
	self.end_headers()
	self.wfile.write(text)
	self.wfile.flush()
	# Make sure to close the socket when we're done
	self.request.socket.close()

    def do_POST(self):
	"""Treat an HTTP POST request as an XMLRPC service call"""
	# NB: XMLRPC faults are not HTTP errors, so the code is always 200,
	# unless an HTTP error occurs, which we don't handle.

	resp = None
	data = None
	method = None
	cl = int(self.headers['content-length'])
	data = self.rfile.read(cl)

	try:
	    params, method = xmlrpclib.loads(data)
	except xmlrpclib.ResponseError:
	    data = xmlrpclib.dumps(xmlrpclib.Fault("Client", 
		"Malformed request"), methodresponse=True)

	if method != None:
	    try:
		resp = self.xmlrpc_dispatch(method, params,
			    fedid(cert=self.request.get_peer_cert()))
		data = xmlrpclib.dumps((resp,), encoding='UTF-8', 
			methodresponse=True)
	    except xmlrpclib.Fault, f:
		data = xmlrpclib.dumps(f, methodresponse=True)
		resp = None

	self.send_xml(data)

    def log_request(self, code=0, size=0):
	"""
	Log request to the fedd logger
	"""
	self.server.log.info("Successful XMLRPC request code %d" % code)


    def xmlrpc_dispatch(self, method, req, fid):
	"""
	The connection to the implementation, using the  method maps

	The implementation provides a mapping from XMLRPC method name to the
	method in the implementation that provides the service.
	"""
	if self.server.xmlrpc_methods.has_key(method):
	    try:
		return self.server.xmlrpc_methods[method](req, fid)
	    except service_error, e:
		raise xmlrpclib.Fault(e.code_string(), e.desc)
	else:
	    raise xmlrpclib.Fault(100, "Unknown method: %s" % method)