info = {
	'author': 'Jon Bergli Heier',
	'title': 'WolframAlpha calculator',
	'description': 'WolframAlpha calculator',
}

import urllib, urllib2, re
from xml.etree.ElementTree import ElementTree

whitespace_re = re.compile(r'\s+')
unicode_re = re.compile(r'(\\:[\da-f]{4})')

class Module(object):
	config_section = 'module/wacalc'

	def __init__(self, bot):
		self.irc = bot
		if self.irc:
			self.irc.register_keyword('!wacalc', self)
			if config.has_option(self.config_section, 'register_gcalc'):
				# Register gcalc trigger for the obsolete gcalc module
				self.irc.register_keyword('!gcalc', self)

	def keyword(self, nick, channel, kw, msg):
		target = channel if not channel == self.irc.nickname else nick.split('!')[0]
		if not len(msg.strip()):
			self.irc.msg(target, 'Usage: !wacalc query')
			return
		query = {
			'appid': config.get(self.config_section, 'api_key'),
			'format': 'plaintext',
			'input': msg,
		}
		if config.has_option(self.config_section, 'location'):
			query['location'] = config.get(self.config_section, 'location')
		u = urllib2.urlopen('http://api.wolframalpha.com/v2/query?%s' % urllib.urlencode(query))
		xmldoc = ElementTree()
		xmldoc.parse(u)
		xml = xmldoc.getroot()
		if xml.attrib['success'] != 'true':
			tips = xml.find('tips')
			dym = xml.find('didyoumeans')
			message = None
			if tips is not None and len(tips):
				message = 'Tip: %s' % tips[0].attrib['text'].encode('utf-8')
			elif dym is not None and len(dym):
				# TODO: sort by score
				message = 'Did you mean "%s"?' % dym[0].text.encode('utf-8')
			if message:
				message = 'No result (%s)' % message
			else:
				message = 'No result.'
			self.irc.msg(target, message)
			return

		right = None
		left = msg
		def pod_plaintext(pod):
			result = pod.find('subpod/plaintext')
			if result is not None and result.text is not None:
				text = result.text
				text = whitespace_re.sub(' ', text)
				text = unicode_re.sub(lambda match: unichr(int(match.group()[2:], 16)), text)
				return text.encode('utf-8')
		for pod in xml.findall('pod'):
			pod_id = pod.attrib['id']
			if pod_id in ('Result', 'DecimalApproximation'):
				right = pod_plaintext(pod)
			elif pod_id == 'Input':
				left = pod_plaintext(pod)
		if left and right:
			self.irc.msg(target, '%s = %s' % (left, right))
		else:
			self.irc.msg(target, 'Something failed.')