#!/usr/bin/env python
# -*- coding: utf-8 -*-

# Stegano - Stegano is a pure Python steganography module.
# Copyright (C) 2010-2021 Cédric Bonhomme - https://www.cedricbonhomme.org
#
# For more information : https://github.com/cedricbonhomme/Stegano
#
# 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/>

__author__ = "Cedric Bonhomme"
__version__ = "$Revision: 0.8 $"
__date__ = "$Date: 2016/08/04 $"
__revision__ = "$Date: 2019/06/01 $"
__license__ = "GPLv3"

import argparse

try:
    from stegano import lsb
except:
    print("Install Stegano: pipx install Stegano")

from stegano import tools


def main():
    parser = argparse.ArgumentParser(prog="stegano-lsb")
    subparsers = parser.add_subparsers(help="sub-command help", dest="command")

    # Subparser: Hide
    parser_hide = subparsers.add_parser("hide", help="hide help")
    # Original image
    parser_hide.add_argument(
        "-i",
        "--input",
        dest="input_image_file",
        required=True,
        help="Input image file.",
    )
    parser_hide.add_argument(
        "-e",
        "--encoding",
        dest="encoding",
        choices=tools.ENCODINGS.keys(),
        default="UTF-8",
        help="Specify the encoding of the message to hide."
        + " UTF-8 (default) or UTF-32LE.",
    )

    group_secret = parser_hide.add_mutually_exclusive_group(required=True)
    # Non binary secret message to hide
    group_secret.add_argument(
        "-m", dest="secret_message", help="Your secret message to hide (non binary)."
    )
    # Binary secret message to hide
    group_secret.add_argument(
        "-f", dest="secret_file", help="Your secret to hide (Text or any binary file)."
    )

    # Image containing the secret
    parser_hide.add_argument(
        "-o",
        "--output",
        dest="output_image_file",
        required=True,
        help="Output image containing the secret.",
    )

    # Shift the message to hide
    parser_hide.add_argument(
        "-s", "--shift", dest="shift", default=0, help="Shift for the message to hide"
    )

    # Subparser: Reveal
    parser_reveal = subparsers.add_parser("reveal", help="reveal help")
    parser_reveal.add_argument(
        "-i",
        "--input",
        dest="input_image_file",
        required=True,
        help="Input image file.",
    )
    parser_reveal.add_argument(
        "-e",
        "--encoding",
        dest="encoding",
        choices=tools.ENCODINGS.keys(),
        default="UTF-8",
        help="Specify the encoding of the message to reveal."
        + " UTF-8 (default) or UTF-32LE.",
    )
    parser_reveal.add_argument(
        "-o",
        dest="secret_binary",
        help="Output for the binary secret (Text or any binary file).",
    )
    # Shift the message to reveal
    parser_reveal.add_argument(
        "-s", "--shift", dest="shift", default=0, help="Shift for the reveal"
    )

    arguments = parser.parse_args()

    if arguments.command == "hide":
        if arguments.secret_message != None:
            secret = arguments.secret_message
        elif arguments.secret_file != None:
            secret = tools.binary2base64(arguments.secret_file)

        img_encoded = lsb.hide(
            arguments.input_image_file, secret, arguments.encoding, int(arguments.shift)
        )
        try:
            img_encoded.save(arguments.output_image_file)
        except Exception as e:
            # If hide() returns an error (Too long message).
            print(e)

    elif arguments.command == "reveal":
        secret = lsb.reveal(
            arguments.input_image_file, arguments.encoding, int(arguments.shift)
        )
        if arguments.secret_binary != None:
            data = tools.base642binary(secret)
            with open(arguments.secret_binary, "wb") as f:
                f.write(data)
        else:
            print(secret)