import os, traceback

import cherrypy
from genshi.core import Stream
from genshi.output import encode, get_serializer
from genshi.template import Context, TemplateLoader
from genshi.filters import Translator

import gettext

languages = {'en': None, 'de': None, 'ja': None}
for l in languages.keys():
	languages[l] = gettext.translation('subdap',
		os.path.join(os.path.dirname(__file__), 'locale'), [l],
		fallback = True)

def do_translate(text):
	transl = cherrypy.thread_data.translations.gettext(text)
	if type(transl) == unicode:
		return transl
	return transl.decode('utf-8')
_ = do_translate
def select_language():
	if cherrypy.thread_data.lang != None:
		lang = cherrypy.thread_data.lang
		return languages[lang if languages.has_key(lang) else 'en']
	try:
		accept = cherrypy.request.headers['Accept-Language']
		accept = str(accept)
	except Exception:
		accept = None
	if accept is not None:
		for group in accept.split(';'):
			for lang in group.split(','):
				if lang.find('=') >= 0:
					continue
				if lang.find('-') >= 0:
					lang = lang[:lang.find('-')]
				if languages.has_key(lang):
					return languages[lang]

	return languages['en']

def template_loaded(template):
	Translator(do_translate).setup(template)

loader = TemplateLoader(
	os.path.join(os.path.dirname(__file__), 'templates'),
	auto_reload = True,
	callback = template_loaded
)

def render(*args, **kwargs):
	if args:
		assert len(args) == 1, 'Expected exactly one argument, but got %r' % (args,)
		template = loader.load(args[0])
	else:
		template = cherrypy.thread_data.template

	#ctxt = Context(url = cherrypy.url)
	ctxt = Context(url = myurl, lang = cherrypy.thread_data.lang, _ = do_translate)
	ctxt.push(kwargs)
	return template.generate(ctxt)

def exc(exc):
	return render('error.html', details = traceback.format_exc())

def expose(filename, method='html', encoding='utf-8', **options):
	def decorate(func):
		@cherrypy.expose
		def wrapper(*args, **kwargs):
			cherrypy.thread_data.template = loader.load(filename)
			cherrypy.thread_data.func = func
			cherrypy.thread_data.lang = None
			if cherrypy.request.cookie.has_key('lang'):
				cherrypy.thread_data.lang = cherrypy.request.cookie['lang'].value
			if cherrypy.request.params.has_key('lang'):
				cherrypy.thread_data.lang = cherrypy.request.params['lang']
			if cherrypy.thread_data.lang != None:
				cherrypy.response.cookie['lang'] = cherrypy.thread_data.lang
				cherrypy.response.cookie['lang']['path'] = '/'
				cherrypy.response.cookie['lang']['max-age'] = 2419200
				cherrypy.response.cookie['lang']['version'] = 1
			if kwargs.has_key('lang'):
				del kwargs['lang']

			cherrypy.thread_data.translations = select_language()
			cherrypy.response.headers['Vary'] = 'Accept-Language'

			opt = options.copy()
			if method == 'html':
				opt.setdefault('doctype', 'html')
			serializer = get_serializer(method, **opt)
			try:
				stream = func(*args, **kwargs)
			except Exception, e:
				stream = exc(e)
			if not isinstance(stream, Stream):
				return stream
			try:
				return encode(serializer(stream), method = serializer, encoding = encoding)
			except Exception, e:
				return encode(serializer(exc(e)), method = serializer, encoding = encoding)
		return wrapper
	return decorate

def myurl(url):
	return '/subdap/' + url