'''
lang.py

Copyright 2006 Andres Riancho

This file is part of w3af, w3af.sourceforge.net .

w3af is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation version 2 of the License.

w3af is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with w3af; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

'''

import core.controllers.outputManager as om
from core.controllers.basePlugin.baseGrepPlugin import baseGrepPlugin
import core.data.kb.knowledgeBase as kb

class lang(baseGrepPlugin):
	'''
	This plugin reads N pages and determines the language they are written in.
	@author: Andres Riancho ( andres.riancho@gmail.com )
	'''

	def __init__(self):
		baseGrepPlugin.__init__(self)
		
		# Internal variables
		self._exec = True
		
		# Some constants
		self._prepositions = {}
		
		self._prepositions[ 'en' ] = ['aboard','about','above','absent','across','after','against','along','alongside','amid','amidst',\
		'among','amongst','around','as','astride','at','atop','before','behind','below','beneath','beside','besides',\
		'between','beyond','but','by','despite','down','during','except','following','for','from','in','inside','into','like','mid','minus','near',\
		'nearest','notwithstanding','of','off','on','onto','opposite','out','outside','over','past','re','round','save',\
		'since','than','through','throughout','till','to','toward','towards','under','underneath','unlike','until','up',\
		'upon','via','with','within','without']

		
		# The 'a' preposition was removed, cause its also used in english
		self._prepositions[ 'es' ] = ['ante', 'bajo', 'cabe', 'con' , 'contra' , 'de', \
		'desde', 'en', 'entre', 'hacia', 'hasta', 'para', 'por' , 'segun', 'si', 'so', 'sobre', 'tras']
		
	def _testResponse(self, request, response):
		'''
		Get the page indicated by the fuzzableRequest and determine the language using the preposition list.
		
		@parameter fuzzableRequest: A fuzzableRequest instance that contains (among other things) the URL to test.
		'''
		self.is404 = kb.kb.getData( 'error404page', '404' )
		if self.is404 != []:
			if self._exec and not self.is404( response ):
				kb.kb.save( self, 'lang', 'unknown' )
				
				splittedBody = response.getBody().split(' ')
				
				# Init the count map
				numberOfmatches = {}
				for lang in self._prepositions.keys():
					numberOfmatches[ lang ] = 0
				
				# Count prepositions
				for lang in self._prepositions.keys():
					for preposition in self._prepositions[ lang ]:
						if preposition in splittedBody:
							om.out.debug('Found preposition: ' + preposition)
							numberOfmatches[ lang ] += 1
							
				# Determine who is the winner
				def sortfunc(x,y):
					return cmp(y[1],x[1])
					
				items = numberOfmatches.items()
				items.sort( sortfunc )
				
				if items[0][1] > items[1][1] * 2:
					
					# This if was added so no duplicated messages are printed
					# to the user, when w3af runs with multithreading.
					if kb.kb.getData( 'lang', 'lang' ) == 'unknown':
						om.out.information('The page language is: '+ items[0][0] )
						kb.kb.save( self, 'lang', items[0][0] )
					
					# Only run once
					self._exec = False
				else:
					om.out.debug('Could not determine the page language using ' + response.getURL() +', not enough text to make a good analysis.')
					# Keep running until giving a good response...
					self._exec = True
		
		return []
	
	def getOptionsXML(self):
		'''
		This method returns a XML containing the Options that the plugin has.
		Using this XML the framework will build a window, a menu, or some other input method to retrieve
		the info from the user. The XML has to validate against the xml schema file located at :
		w3af/core/ui/userInterface.dtd
		
		@return: XML with the plugin options.
		'''	
		return	'<?xml version="1.0" encoding="ISO-8859-1"?>\
		<OptionList>\
		</OptionList>\
		'
	
	def end( self ):
		if self._exec:
			# I never got executed !
			om.out.information('Could not determine the language of the site. Enable discovery.webSpider and try again.')
	
	def setOptions( self, OptionList ):
		'''
		This method sets all the options that are configured using the user interface 
		generated by the framework using the result of getOptionsXML().
		
		@parameter OptionList: A dictionary with the options for the plugin.
		@return: No value is returned.
		'''	
		pass

	def getPluginDeps( self ):
		'''
		@return: A list with the names of the plugins that should be runned before the
		current one.
		'''
		return ['discovery.error404page']
	
	def getLongDesc( self ):
		'''
		@return: A DETAILED description of the plugin functions and features.
		'''
		return '''
		This plugin reads N pages and determines the language the site is written in. This is done
		by saving a list of prepositions in different languages, and counting the number of matches
		on every page.
		'''