tzxcat

#!/usr/bin/env python3
#
# tzxtools - a collection for processing tzx files
#
# Copyright (C) 2016 Richard "Shred" Körber
#   https://github.com/shred/tzxtools
#
# This program 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, 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

import argparse
import sys

from tzxlib.tzxfile import TzxFile
from tzxlib.convert import convertToText

def writeBlock(out, block, index, convert):
    if not block.tap.valid():
        print('Warning: Block %d has bad CRC' % (index), file=sys.stderr)
    if convert:
        out.write(convertToText(block.tap.body()).encode('utf-8'))
    else:
        block.tap.writeBody(out)

def writeSingleBlock(tzx, out, index, convert):
    if index < 0 or index >= len(tzx.blocks):
        print('Error: Block %d out of range' % (index), file=sys.stderr)
        exit(1)
    b = tzx.blocks[index]
    if not hasattr(b, 'tap'):
        print('Error: Block %d has no data content' % (index), file=sys.stderr)
        exit(1)
    writeBlock(out, b, index, convert)

def writeAllBlocks(tzx, out, convert):
    cnt = 0
    for b in tzx.blocks:
        if hasattr(b, 'tap'):
            writeBlock(out, b, cnt, convert)
        cnt += 1

parser = argparse.ArgumentParser(description='Write data block content')
parser.add_argument('file',
            nargs='?',
            default='/dev/stdin',
            help='TZX file, stdin if omitted')
parser.add_argument('-b', '--block',
            dest='block',
            type=int,
            metavar='NR',
            help='block number to cat')
parser.add_argument('-o', '--to',
            dest='to',
            metavar='TARGET',
            default='/dev/stdout',
            help='target file, stdout if omitted')
parser.add_argument('-t', '--text',
            dest='text',
            action='store_true',
            help='convert ZX Spectrum text to UTF-8')
args = parser.parse_args()

file = TzxFile()
file.read(args.file or '/dev/stdin')

with open(args.to, 'wb') as out:
    if args.block != None:
        writeSingleBlock(file, out, args.block, args.text)
    else:
        writeAllBlocks(file, out, args.text)