#!/usr/bin/env python
     # encoding: utf-8
     #
     # Copyright (c) 2010 Doug Hellmann.  All rights reserved.
     #
     """Using the incremental reader/writer interfaces.
     """
     #end_pymotw_header
     
     import codecs
     import sys
     
     from codecs_to_hex import to_hex
     
     text = 'abcdefghijklmnopqrstuvwxyz\n'
     repetitions = 50
     
     print 'Text length :', len(text)
     print 'Repetitions :', repetitions
     print 'Expected len:', len(text) * repetitions
     
     # Encode the text several times build up a large amount of data
     encoder = codecs.getincrementalencoder('bz2')()
     encoded = []
     
     print
     print 'Encoding:',
     for i in range(repetitions):
         en_c = encoder.encode(text, final = (i==repetitions-1))
         if en_c:
             print '\nEncoded : {} bytes'.format(len(en_c))
             encoded.append(en_c)
         else:
             sys.stdout.write('.')
         
     bytes = ''.join(encoded)
     print
     print 'Total encoded length:', len(bytes)
     print
     
     # Decode the byte string one byte at a time
     decoder = codecs.getincrementaldecoder('bz2')()
     decoded = []
     
     print 'Decoding:',
     for i, b in enumerate(bytes):
         final= (i+1) == len(text)
         c = decoder.decode(b, final)
         if c:
             print '\nDecoded : {} characters'.format(len(c))
             print 'Decoding:',
             decoded.append(c)
         else:
             sys.stdout.write('.')
     print
     
     restored = u''.join(decoded)
     
     print
     print 'Total uncompressed length:', len(restored)