#!/usr/bin/python
"""This is a Python client library for the Dojo Learning REST API.
For more information and documentation, visit:

http://www.dojolearning.com/developers

Requires the simplejson package, available here:

http://pypi.python.org/pypi/simplejson

Example usage:

from dojolearning import DojoLearning

dojo = DojoLearning ('user', 'apikey')

topics = dojo.lesson_topics ();

for topic in topics:
	print '<h2>%s</h2>' % topic['name']

	lessons = dojo.lesson_list (topic['id'], 0)

	for lesson in lessons:
		print '<a href="%s">%s</a><br />' % (lesson['url'], lesson['title'])
"""

__author__ = 'John Luxford <lux@dojolearning.com>'
__copyright__ = 'Copyright (c) 2008 Dojo Learning'
__license__ = 'LGPL, http://opensource.org/licenses/lgpl-2.1.php'
__version__ = '1.0'

import new
import urllib
import simplejson

class transplant:
   def __init__ (self, method, host, method_name = None):
      self.host = host
      self.method = method
      setattr (host, method_name or method.__name__, self)

   def __call__ (self, *args, **kwargs):
      nargs = [self.host]
      nargs.extend (args)
      return apply (self.method, nargs, kwargs)

# Dojo Learning client class.
class DojoLearning:
	uri = 'http://api.dojolearning.com/rest-action/%s?user=%s&apikey=%s%s'
	post_uri = 'http://api.dojolearning.com/rest-action/%s'
	post_args = 'user=%s&apikey=%s%s'
	user = ''
	apikey = ''
	errno = 0
	error = ''
	method_list = []

	# Constructor method.
	def __init__ (self, user, apikey):
		self.user = user
		self.apikey = apikey

		# Generate the dynamic methods
		self.method_list = self.send_and_receive ('', '')
		for k, v in self.method_list.iteritems ():
			self.add_method (k, v)

	# Send, receive and parse the request.
	def send_and_receive (self, request, params):
		# determine request type
		if self.method_list and self.method_list[request]:
			method = self.method_list[request]['method']
		else:
			method = 'GET'

		if method == 'GET':
			# handle GET requests
			url = self.uri % (request, self.user, self.apikey, params)
	
			try:
				req = urllib.urlopen (url)
			except IOError:
				self.errno = 401
				self.error = 'Unauthorized'
				return None
		else:
			# handle POST requests
			url = self.post_uri % (request)
			params = self.post_args % (self.user, self.apikey, params)

			try:
				req = urllib.urlopen (url, params)
			except IOError:
				self.errno = 401
				self.error = 'Unauthorized'
				return None

		res = req.read ()

		return simplejson.loads (res)

	# Dynamically add methods to the object
	def add_method (self, name, data):
		method_name = name.replace ('.', '_')

		code = "def " + method_name + ' (self'

		for param in data['parameters']:
			code += ', ' + param

		code += "):\n"

		code += "\tm = '" + name + "'\n"
		code += "\tp = ''\n"
		if len (data['parameters']) > 0:
			for k in data['parameters']:
				code += "\tp += '&" + k + "=' + urllib.quote_plus(str(" + k + "))\n"

		code += "\treturn self.send_and_receive (m, p)\n"

		code += "\n\n"
		#print code

		exec (code)

		func = eval(method_name);
		transplant (func, self, method_name)

if __name__ == '__main__':
	dojo = DojoLearning ('user', 'apikey')

	topics = dojo.lesson_topics ()

	for topic in topics:
		print '<h2>%s</h2>' % topic['name']

		lessons = dojo.lesson_list (topic['id'], 0)

		for lesson in lessons:
			print '<a href="%s">%s</a><br />' % (lesson['url'], lesson['title'])