# -*- coding: utf-8 -*-
# Normalizer Program
# Copyright 2008 Santhosh Thottingal <santhosh.thottingal@gmail.com>
# http://www.smc.org.in
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 Lesser General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#

import codecs
import os

class Normalizer:

	def __init__(self):
		self.rules_file = os.path.join(os.path.dirname(__file__),"normalizer_ml.rules")
		self.rulesDict = dict()

	def normalize(self, text):
		self.rulesDict = self.LoadRules()
		words = text.split(" ")
		word_count = len(words)
		result = []
		for word in words:
			word = self.trim(word)
			word_length = len(word)
			suffix_pos_itr = 2
			word_stemmed = ""
			while suffix_pos_itr < word_length :
				suffix = word[suffix_pos_itr:word_length]
				if suffix in self.rulesDict:
					word_stemmed = word[0:suffix_pos_itr] + self.rulesDict[suffix]
					break
				suffix_pos_itr = suffix_pos_itr+1
			if(word_stemmed == ""):
				word_stemmed = word
			result.append(word_stemmed)
		return "  ".join(result)

	def LoadRules(self):
		rules_dict = dict()
		line = []
		line_number = 0
		rule_number = 0
		rules_file = codecs. open(self.rules_file,encoding='utf-8', errors='ignore')
		while 1:
			line_number = line_number +1
   			text = unicode( rules_file.readline())
			if text == "":
			      break
			if text[0] == '#':
			      continue  #this is a comment - ignore
			text = text.split("#")[0]   #remove the comment part of the line
			line_number = line_number +1
			line = text.strip()  # remove unwanted space
			if(line == ""):
				  continue
			if(len(line.split("=")) != 2):
					print "[Error] Syntax Error in the Rules. Line number: ",  line_number
				  	print "Line: "+ text
				  	continue
	 		lhs = line.split("=") [ 0 ]  .strip()
	 		rhs = line.split("=") [ 1 ]  .strip()
	 		if(len(rhs)>0):
	 			if(lhs[0]=='"'):
	 				lhs=lhs[1:len(lhs)] # if the string is "quoted"
	 			if(lhs[len(lhs)-1]=='"'):
	 				lhs=lhs[0:len(lhs)-1] # if the string is "quoted"
	 		if(len(rhs)>0):
	 			if(rhs[0]=='"'):
	 				rhs=rhs[1:len(rhs)]  # if the string is "quoted"
	 			if(rhs[len(rhs)-1]=='"'):
	 				rhs=rhs[0:len(rhs)-1]	 # if the string is "quoted"
	 		rule_number=rule_number+1
			rules_dict[lhs]=rhs
			#print "[", rule_number ,"] " +lhs + " : " +rhs
		print "Found ",rule_number, " rules."
		return rules_dict

	def trim(self,word):
		punctuations=['~','!','@','#','$','%','^','&','*','(',')','-','+','_','=','{','}','|' ,':',';','<','>','\,','.','?']
		word=word.strip()
		index=len(word)-1
		while index>0:
			if word[index] in punctuations:
				word=word[0:index]
			else:
				break
			index=index-1
		return word
	def process(self, form):
		response = """
		<h2>Normalizer</h2></hr>
		<p>Enter the text for normalizing in the below text area.
		 Language of each  word will be detected.
		 You can give the text in any language and even with mixed language
		</p>
		<form action="" method="post">
		<textarea cols='100' rows='25' name='input_text' id='id1'>%s</textarea>
		<input  type="submit" id="Stem" value="Normalize"  name="action" style="width:12em;"/>
		<input type="reset" value="Clear" style="width:12em;"/>
		</br>
		</form>
		"""
		if(form.has_key('input_text')):
			text = form['input_text'].value	.decode('utf-8')
			response=response % text
			result_dict = self.normalize(text)
			response = response+"<h2>Normalized Result</h2></hr>"
			response = response+"<table class=\"table1\"><tr><th>Word</th><th>Normalized form</th></tr>"
			for key in result_dict:
				response = response+"<tr><td>"+key+"</td><td>"+result_dict[key]+"</td></tr>"
			response = response+"</table>	"
		else:
			response=response % ""
		return response
	def get_module_name(self):
		return "Normalizer"
	def get_info(self):
		return 	"Malayalam Normalizer(Experimental)"

def getInstance():
	return Normalizer()