BR2 Dialogue Script Dumper v1

import struct
import os
import sys

def get_data(filename):
    with open(filename, 'rb') as f:
        return f.read()

def is_jis_char(s):
    try:
        s.decode('cp932')
    except UnicodeDecodeError:
        return False
    if len(s.decode('cp932')) == 1:
        return True
    return False

def script_unpack(filename):
    filedata = get_data(filename)
    num_of_records = struct.unpack('<H',filedata[:2])[0] / 2
    pos = 0
    ptrs = []
    for i in range(num_of_records):
        ptr = struct.unpack('<H',filedata[pos:pos+2])[0]
        tmp_list = [x[1] for x in ptrs]
        if ptr in tmp_list:
    ##        print 'hit'
            ptrs.append(('duplicate',tmp_list.index(ptr)))
        else:
            ptrs.append((i, ptr))
        pos += 2
    output = [filename + '\n']
    for i, (num, ptr) in enumerate(ptrs):
        if isinstance(num, basestring):
            output.append(str(i) + '\tDuplicate of {}\n'.format(str(ptr)))
            continue
        output.append(str(i) + '\t')
        pos = ptr
        while True:
            if is_jis_char(filedata[pos:pos+2]):
                output.append(filedata[pos:pos+2])
    ##            print filedata[pos:pos+2].decode('cp932')
                pos += 2
            elif (ord(filedata[pos]) > 0x19 and ord(filedata[pos]) < 0x80) or \
                    (ord(filedata[pos]) > 0xa0 and ord(filedata[pos]) < 0xe0):
                output.append(filedata[pos])
                pos += 1
            elif filedata[pos] == '\x0d':
                output.append('\tlinebreak\n\t')
                pos += 1
            elif filedata[pos:pos+2] == '\x08\x0d':
                output.append('\tPTT\n\t')
                pos += 2
            elif filedata[pos:pos+2] == '\x08\x03':
                output.append('\tpagebreak\n\t')
                pos += 2
            elif filedata[pos] == '\x08':
                output.append('\tpause\n\t')
                pos += 1
            elif filedata[pos] == '\x03':
                output.append('\tpagebreak2\n\t')
                pos += 1
            elif filedata[pos:pos+2] == '\x00\x00':
                output.append('\tterminalcode\n\t')
                break
            elif filedata[pos] == '\x00':
                output.append('\tnull\n\t')
                pos += 1
            else:
                print i, hex(pos)
                quit()
        output[-1] = output[-1][:-1]

    with open(os.path.splitext(filename)[0] + '.tsv', 'wb') as f:
        f.write(''.join(output))

if __name__ == '__main__':
    if len(sys.argv) < 2:
        print ('Usage:\n'
               'python script.py script_file_name_minus_extension')
        quit()
##    For use with IDLE
##    sys.argv.append('TALK01')
    script_unpack(sys.argv[1] + '.bzh')