#!/usr/bin/python

# Copyright 2011 Christian Haselgrove
# Licensed under the BSD License: http://www.opensource.org/licenses/bsd-license.php

import sys
import os
import getopt
import getpass
import base64
import urlparse
import httplib

def report_error(msg):
	sys.stderr.write('%s: %s\n' % (progname, msg))
	sys.stderr.write('run %s with no arguments for usage\n' % progname)
	return

def debug(msg):
	if debug_flag:
		print msg
	return

progname = os.path.basename(sys.argv[0])

try:
	host = os.environ['XRC_HOST']
except KeyError:
	host = None

try:
	user_name = os.environ['XRC_USER']
except KeyError:
	user_name = None

try:
	password = os.environ['XRC_PASSWORD']
except KeyError:
	password = None

if len(sys.argv) == 1:
	print
	print 'usage: %s [options] <method> <request>' % progname
	print
	print 'call an XNAT REST service'
	print
	print 'options are:'
	print
	print '    -d -- debug'
	print '    -h <host>'
	print '    -u <user name>'
	print '    -p <password>'
	print
	print 'option values may be given by environment variables:'
	print
	if host is None:
		print '    host: XRC_HOST'
	else:
		print '    host: XRC_HOST (set to %s)' % host
	if user_name is None:
		print '    user name: XRC_USER'
	else:
		print '    user name: XRC_USER (set to %s)' % user_name
	if password is None:
		print '    password: XRC_PASSWORD'
	else:
		print '    password: XRC_PASSWORD (currently set)'
	print
	print '%s will prompt for a missing user name, password, or host' % progname
	print
	print 'method must be GET, PUT, POST, or DELETE'
	print
	print 'cheat sheet (see also http://docs.xnat.org/XNAT+REST+API):'
	print
	print '    /data/JSESSION'
	print
	sys.exit(1)

try:
	(opts, args) = getopt.getopt(sys.argv[1:], 'h:u:p:d')
except getopt.error, data:
	report_error(data)
	sys.exit(1)

if len(args) < 2:
	report_error('not enough non-option arguments')
	sys.exit(1)

if len(args) > 2:
	report_error('not enough non-option arguments')
	sys.exit(1)

(method, request) = args

if method not in ('GET', 'PUT', 'POST', 'DELETE'):
	report_error('unknown method "%s"' % method)
	sys.exit(1)

if not request.startswith('/'):
	report_error('request must start with "/"')
	sys.exit(1)

debug_flag = False

for (option, value) in opts:
	if option == '-h':
		host = value
	if option == '-u':
		user_name = value
	if option == '-p':
		password = value
	if option == '-d':
		debug_flag = True

if host is None:
	sys.stdout.write('Host: ')
	sys.stdout.flush()
	host = sys.stdin.readline().strip()

if user_name is None:
	sys.stdout.write('User name: ')
	sys.stdout.flush()
	user_name = sys.stdin.readline().strip()

if password is None:
	password = getpass.getpass()

host = host.rstrip('/')

auth = 'Basic %s' % base64.b64encode('%s:%s' % (user_name, password))

url_parts = urlparse.urlsplit(host)

hc = httplib.HTTPConnection(url_parts.netloc)
try:
	path = '%s%s' % (url_parts.path, request)
	debug('method: %s' % method)
	debug('path: %s' % path)
	debug('authorization: %s' % auth)
	hc.request(method, path, headers={'Authorization': auth})
	response = hc.getresponse()
	data = response.read()
finally:
	hc.close()

for (name, value) in response.getheaders():
	print '%s: %s' % (name, value)

print

print data

sys.exit(0)

# eof