#!/bin/python

try:
  import signal
  signal.signal(signal.SIGPIPE, signal.SIG_DFL)
except:
  pass

import sys, struct

def fail(msg):
  sys.stderr.write(msg + '\n')
  sys.exit(1)
if len(sys.argv) < 2: fail('usage: %s foo.gblorb' % sys.argv[0])
gblorb = open(sys.argv[1]).read()
i = gblorb.find('Glul\x00')
if i == -1: fail('not a .glulx or .gblorb file')
glulx = gblorb[i:]
u8 = lambda addr: ord(glulx[addr])
u32 = lambda addr: struct.unpack_from('!I', glulx, addr)[0]

ram_start = u32(8)
string_table_start = u32(28)
string_table_size = u32(string_table_start)
string_table_end = string_table_start + string_table_size
huffman_root = u32(string_table_start + 8)
code_start, code_end = 0, string_table_start
data_start, data_end = string_table_end, ram_start

def decode_u8(addr):
  end = glulx.find('\x00', addr)
  if end == -1: return
  return glulx[addr:end].decode('latin1')

def decode_u32(addr):
  result = []
  while True:
    v = u32(addr)
    if v == 0: return u''.join(result)
    result.append(unichr(v))
    addr += 4

def decode_huffman(addr):
  result = []
  p = huffman_root
  bit = -1
  while True:
    bit += 1
    if bit == 8:
      bit = 0
      addr += 1
    v = (u8(addr) >> bit) & 1
    assert u8(p) == 0
    p = u32(p + 1 + 4*v)
    op = u8(p)
    if op == 0: continue
    elif op == 1: return u''.join(result)
    elif op == 2: result.append(unichr(u8(p+1)))
    elif op == 3: result.append(decode_u8(p+1))
    elif op == 4: result.append(unichr(u32(p+1)))
    elif op == 5: result.append(decode_u32(p+1))
    else: result.append(u'<<???>>')
    p = huffman_root

def find_strings():
  visited = set()
  for i in xrange(code_start, code_end):
    p = u32(i)
    if p < data_start or p >= data_end: continue
    if glulx[p] == '\xe1': s = decode_huffman(p+1)
    elif glulx[p:p+4] == '\xe2\x00\x00\x00': s = decode_u32(p+4)
    elif glulx[p] == '\xe0': s = decode_u8(i+1)
    else: s = None
    if s: yield s, p, i

def main():
  for s, p, i in find_strings():
    if not s: continue
    s = s.rstrip()
    if not s: continue
    print(s.encode('utf8'))

main()

"""
https://github.com/jcmf/glulx-strings
License

Copyright (c) 2015 Jacques Frechet
The MIT License (MIT)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

"""