#!/usr/bin/env python3

# Copyright (C) 2015-2021  Chris Lalancette <clalancette@gmail.com>

# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation;
# version 2.1 of the License.

# This library 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
# Lesser General Public License for more details.

# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

"""
The main code for the pycdlib-explorer tool, which can open, read, write,
and otherwise manipulate ISOs in an interactive way.
"""

from __future__ import print_function

import cmd
import collections
import os
import shlex
import sys

import pycdlib


class PyCdlibCmdLoop(cmd.Cmd):
    """The main class dealing with the pycdlib-explorer command loop."""
    PRINT_MODES = ('iso9660', 'rr', 'joliet', 'udf')

    def __init__(self, iso):
        cmd.Cmd.__init__(self)
        self.iso = iso
        self.cwds = {}
        for mode in self.PRINT_MODES:
            self.cwds[mode] = '/'
        self.print_mode = 'iso9660'
        self.encoding = 'utf-8'
        self.pathname = 'iso_path'

    prompt = '(pycdlib) '

    def help_exit(self):  # pylint: disable=no-self-use
        """The help method for the 'exit' command."""
        print('> exit')
        print('Exit the program.')

    def do_exit(self, line):  # pylint: disable=no-self-use
        """The command to quit the program."""
        if line:
            print('No parameters allowed for exit')
            return False
        return True

    def help_quit(self):  # pylint: disable=no-self-use
        """The help method for the 'quit' command."""
        print('> quit')
        print('Exit the program.')

    def do_quit(self, line):  # pylint: disable=no-self-use
        """The other command to quit the program."""
        if line:
            print('No parameters allowed for quit')
            return False
        return True

    def do_EOF(self, line):  # pylint: disable=unused-argument,no-self-use
        """Handel EOF on the terminal."""
        print()
        return True

    def help_print_mode(self):  # pylint: disable=no-self-use
        """The help method for the 'print_mode' command."""
        print('> print_mode [iso9660|rr|joliet|udf]')
        print("Change which 'mode' of filenames are printed out.  There are four main\n"
              'modes: ISO9660 (iso9660, the default), Rock Ridge (rr), Joliet (joliet), and\n'
              'UDF (udf).  The original iso9660 mode only allows filenames of 8 characters,\n'
              'plus 3 for the extension.  The Rock Ridge extensions allow much longer\n'
              'filenames and much deeper directory structures.  The Joliet extensions also\n'
              'allow longer filenames and deeper directory structures, but in an entirely\n'
              'different namespace (though in most circumstances, the Joliet namespace will\n'
              'mirror the ISO9660/Rock Ridge namespace).  The UDF Bridge extensions add an\n'
              'entirely parallel UDF namespace to the ISO as well.  Any given ISO will always\n'
              'have ISO9660 mode, but may have any combination of Rock Ridge, Joliet, and UDF\n'
              '(including none of them).  Running this command with no arguments prints out\n'
              "the current mode.  Passing 'iso9660' as an argument sets it to the original\n"
              "ISO9660 mode.  Passing 'rr' as an argument sets it to Rock Ridge mode.  Passing\n"
              "'joliet' as an argument sets it to Joliet mode.  Passing 'udf' as an argument\n"
              'sets it to UDF mode.')

    def do_print_mode(self, line):  # pylint: disable=no-self-use
        """
        The command to change whether the explorer is printing in iso9660,
        joliet, rr, or udf (see help for more details).
        """
        split = shlex.split(line)
        splitlen = len(split)
        if splitlen == 0:
            print(self.print_mode)
            return False
        if splitlen != 1:
            print('Only a single parameter allowed for print_mode')
            return False

        if split[0] not in self.PRINT_MODES:
            print("Parameter for print_mode must be one of '" + "', ".join(self.PRINT_MODES) + "'")
            return False

        if split[0] == 'rr' and not self.iso.has_rock_ridge():
            print('Can only enable Rock Ridge names for Rock Ridge ISOs')
            return False

        if split[0] == 'joliet' and not self.iso.has_joliet():
            print('Can only enable Joliet names for Joliet ISOs')
            return False

        if split[0] == 'udf' and not self.iso.has_udf():
            print('Can only enable UDF names for UDF ISOs')
            return False

        self.print_mode = split[0]

        pathstart = split[0]
        if split[0] == 'iso9660':
            pathstart = 'iso'

        self.pathname = pathstart + '_path'

        self.encoding = 'utf-8'
        if split[0] == 'joliet':
            self.encoding = 'utf-16_be'

        return False

    def help_ls(self):  # pylint: disable=no-self-use
        """The help method for the 'ls' command."""
        print('> ls')
        print('Show the contents of the current working directory. The format of the output is:\n')
        print('TYPE(F=file, D=directory) NAME SIZE')

    def do_ls(self, line):  # pylint: disable=no-self-use
        """The command to list the contents of a directory."""
        if line:
            print('No parameters allowed for ls')
            return False

        diriter = self.iso.list_children(**{self.pathname: self.cwds[self.print_mode]})

        for child in diriter:
            if child is None:
                prefix = 'D'
                name = '..'
            else:
                prefix = 'F'
                if child.is_dir():
                    prefix = 'D'
                name = child.file_identifier().decode(self.encoding)
                if self.print_mode == 'rr':
                    name = ''
                    if child.is_dot():
                        name = '.'
                    elif child.is_dotdot():
                        name = '..'
                    else:
                        if child.rock_ridge is not None and child.rock_ridge.name() != '':
                            name = child.rock_ridge.name().decode('utf-8')
                            if child.rock_ridge.is_symlink():
                                name += ' -> %s' % (child.rock_ridge.symlink_path())
                                prefix += 'S'

            size = ''
            if child is not None and child.is_file():
                if isinstance(child, pycdlib.udf.UDFFileEntry):
                    size = child.info_len
                else:
                    size = child.data_length

            print('%2s %s %s' % (prefix, name, size))

        return False

    def help_cd(self):  # pylint: disable=no-self-use
        """The help method for the 'cd' command."""
        print('> cd <iso_dir>')
        print('Change directory to <iso_dir> on the ISO.')

    def do_cd(self, line):  # pylint: disable=no-self-use
        """
        The command to change the current working directory.
        """
        split = shlex.split(line)
        if len(split) != 1:
            print('The cd command supports one and only one parameter')
            return False

        directory = split[0]

        if directory[0] != '/':
            tmp = self.cwds[self.print_mode] + '/' + directory
            directory = pycdlib.utils.normpath(tmp).decode('ascii')

        rec = self.iso.get_record(**{self.pathname: directory})

        if not rec.is_dir():
            print('Entry %s is not a directory' % (directory))
            return False
        self.cwds[self.print_mode] = directory

        return False

    def help_get(self):  # pylint: disable=no-self-use
        """The help method for the 'get' command."""
        print('> get <iso_file> <out_file>')
        print('Get the contents of <iso_file> from the ISO and write them to <out_file>.')

    def do_get(self, line):  # pylint: disable=no-self-use
        """
        The command to extract a file from the ISO.
        """
        split = shlex.split(line)
        if len(split) != 2:
            print('The get command must be passed two parameters.')
            return False

        iso_file = split[0]
        outfile = split[1]

        if iso_file[0] != '/':
            tmp = self.cwds[self.print_mode] + '/' + iso_file
            iso_file = pycdlib.utils.normpath(tmp).decode('ascii')

        self.iso.get_file_from_iso(outfile, **{self.pathname: iso_file})

        return False

    def help_cwd(self):  # pylint: disable=no-self-use
        """The help method for the 'cwd' command."""
        print('> cwd')
        print('Show the current working directory.')

    def do_cwd(self, line):  # pylint: disable=no-self-use
        """The command to find out what the current working directory is."""
        if line:
            print('No parameters allowed for cwd')
            return False

        print(self.cwds[self.print_mode])

        return False

    def help_tree(self):  # pylint: disable=no-self-use
        """The help method for the 'tree' command."""
        print('> tree')
        print("Print all files and subdirectories below the current directory (similar to the Unix 'tree' command).")

    def do_tree(self, line):  # pylint: disable=no-self-use
        """
        The command to print out all of the files and directories below the
        current working directory in a convenient tree-like form.
        """
        if line:
            print('No parameters allowed for tree')
            return False

        utf8_corner = '└──'
        utf8_middlebar = '├──'
        utf8_vertical_line = '│'

        entry = self.iso.get_record(**{self.pathname: self.cwds[self.print_mode]})

        dirs = collections.deque([(entry, [])])
        while dirs:
            dir_record, lasts = dirs.popleft()
            prefix = ''
            if lasts:
                for last in lasts[:-1]:
                    if last:
                        prefix += '    '
                    else:
                        prefix += utf8_vertical_line + '   '

                if lasts[-1]:
                    prefix += utf8_corner + ' '
                else:
                    prefix += utf8_middlebar + ' '

            name = dir_record.file_identifier()
            if self.print_mode == 'rr':
                if dir_record.rock_ridge is not None and dir_record.rock_ridge.name() != '':
                    name = dir_record.rock_ridge.name()

            print('%s%s' % (prefix, name.decode('utf-8')))

            if not dir_record.is_dir():
                continue

            tmp = collections.deque()
            new_lasts = lasts + [False]
            if self.print_mode == 'udf':
                for d in dir_record.fi_descs:
                    child = d.file_entry
                    if child is None:
                        continue
                    tmp.appendleft((child, new_lasts))
            else:
                for child in dir_record.children:
                    if child.is_dot() or child.is_dotdot():
                        continue
                    tmp.appendleft((child, new_lasts))
            if tmp:
                tmp.popleft()
                tmp.appendleft((child, lasts + [True]))
            dirs.extendleft(tmp)

        return False

    def help_write(self):  # pylint: disable=no-self-use
        """The help method for the 'write' command."""
        print('> write <out_file>')
        print('Write the current ISO contents to <out_file>.')

    def do_write(self, line):  # pylint: disable=no-self-use
        """
        The command to write the ISO out to a new file.
        """
        split = shlex.split(line)
        if len(split) != 1:
            print('The write command supports one and only one parameter.')
            return False

        out_name = split[0]

        self.iso.write(out_name)

        return False

    def help_add_file(self):  # pylint: disable=no-self-use
        """The help method for the 'add_file' command."""
        print('> add_file <iso_path> <src_filename> [rr_name=<rr_name>] [joliet_path=<joliet_path>]')
        print('Add the contents of <src_filename> to the ISO at the location specified in <iso_path>.')
        print('If the ISO is a Rock Ridge ISO, <rr_name> must be specified; otherwise, it must not be.')
        print('If the ISO is not a Joliet ISO, <joliet_path> must not be specified.  If the ISO is a')
        print('Joliet ISO, <joliet_path> is optional, but highly recommended to supply.')

    def do_add_file(self, line):  # pylint: disable=no-self-use
        """
        The command to add a new file to the ISO from the local filesystem.
        """
        split = shlex.split(line)

        if len(split) < 2 or len(split) > 4:
            self.help_add_file()
            return False

        iso_path = split[0]
        src_path = split[1]
        rr_name = None
        joliet_path = None

        for arg in split[2:]:
            keyval = arg.split('=')
            if len(keyval) != 2:
                print('Invalid key/val pair, must be rr_name=<rr_name> or joliet_path=<joliet_path>')
                return False

            key = keyval[0]
            val = keyval[1]

            if key == 'rr_name':
                rr_name = val
            elif key == 'joliet_path':
                joliet_path = val
            else:
                print('Unknown key, must be rr_name=<rr_name> or joliet_path=<joliet_path>')
                return False

        if self.iso.has_rock_ridge() and rr_name is None:
            print('The ISO is Rock Ridge, so a <rr_name> parameter must be specified.')
            return False

        if iso_path[0] != '/':
            tmp = self.cwds['iso9660'] + '/' + iso_path
            iso_path = pycdlib.utils.normpath(tmp).decode('ascii')

        self.iso.add_file(src_path, iso_path, rr_name=rr_name, joliet_path=joliet_path)

        return False

    def help_modify_file_in_place(self):  # pylint: disable=no-self-use
        '''
        The help method for the 'modify_file_in_place' command.
        '''
        print('> modify_file_in_place <iso_path> <src_filename>')
        print('Replace the contents of the file within the ISO specified in <iso_path> with that of <src_filename>.')
        print('Warning: This command modifies the opened ISO file in-place.')
        print('You must start %s with the `--read-write` flag to enable this.' % (sys.argv[0]))
        print('<src_filename> must occupy the same number of extents as the original file.')

    def do_modify_file_in_place(self, line):  # pylint: disable=no-self-use
        '''
        The command to replace an existing file in the ISO from the local filesystem.
        '''
        split = shlex.split(line)

        if len(split) != 2:
            self.help_modify_file_in_place()
            return False

        iso_path = split[0]
        src_path = split[1]

        if iso_path[0] != '/':
            tmp = self.cwds['iso9660'] + '/' + iso_path
            iso_path = pycdlib.utils.normpath(tmp).decode('ascii')

        with open(src_path, 'rb') as src_fp:
            self.iso.modify_file_in_place(src_fp, os.stat(src_path).st_size, iso_path)

        return False

    def help_rm_file(self):  # pylint: disable=no-self-use
        """The help method for the 'rm_file' command."""
        print('> rm_file <iso_path>')
        print('Remove the contents of <iso_path> from the ISO.')

    def do_rm_file(self, line):  # pylint: disable=no-self-use
        """
        The command to remove a file from the ISO.
        """
        split = shlex.split(line)
        if len(split) != 1:
            print('The rm_file command takes one and only one parameter (iso path).')
            return False

        iso_path = split[0]

        if iso_path[0] != '/':
            tmp = self.cwds['iso9660'] + '/' + iso_path
            iso_path = pycdlib.utils.normpath(tmp).decode('ascii')

        self.iso.rm_file(iso_path)

        return False

    def help_mkdir(self):  # pylint: disable=no-self-use
        """The help method for the 'mkdir' command."""
        print('> mkdir <iso_path> [rr_name=<rr_name>] [joliet_path=<joliet_path>]')
        print('Make a new directory called <iso_path>.')
        print('If the ISO is a Rock Ridge ISO, <rr_name> must be specified; otherwise, it must not be.')
        print('If the ISO is not a Joliet ISO, <joliet_path> must not be specified.  If the ISO is a')
        print('Joliet ISO, <joliet_path> is optional, but highly recommended to supply.')

    def do_mkdir(self, line):  # pylint: disable=no-self-use
        """
        The command to make a new directory on the ISO.
        """
        split = shlex.split(line)

        if not split or len(split) > 3:
            self.help_mkdir()
            return False

        iso_path = split[0]
        rr_name = None
        joliet_path = None

        for arg in split[1:]:
            keyval = arg.split('=')
            if len(keyval) != 2:
                print('Invalid key/val pair, must be rr_name=<rr_name> or joliet_path=<joliet_path>')
                return False

            key = keyval[0]
            val = keyval[1]

            if key == 'rr_name':
                rr_name = val
            elif key == 'joliet_path':
                joliet_path = val
            else:
                print('Unknown key, must be rr_name=<rr_name> or joliet_path=<joliet_path>')
                return False

        if self.iso.has_rock_ridge() and rr_name is None:
            print('The ISO is Rock Ridge, so a <rr_name> parameter must be specified.')
            return False

        if iso_path[0] != '/':
            tmp = self.cwds['iso9660'] + '/' + iso_path
            iso_path = pycdlib.utils.normpath(tmp).decode('ascii')

        self.iso.add_directory(iso_path, rr_name=rr_name, joliet_path=joliet_path)

        return False

    def help_rmdir(self):  # pylint: disable=no-self-use
        """The help method for the 'rmdir' command."""
        print('> rmdir <iso_path>')
        print('Remove the directory at <iso_path>.  Note that the directory must be empty for the command to succeed.')

    def do_rmdir(self, line):  # pylint: disable=no-self-use
        """
        The command to remove a directory from the ISO.
        """
        split = shlex.split(line)
        if len(split) != 1:
            print('The rmdir command takes one and only one parameter (iso path).')
            return False

        iso_path = split[0]

        if iso_path[0] != '/':
            tmp = self.cwds['iso9660'] + '/' + iso_path
            iso_path = pycdlib.utils.normpath(tmp).decode('ascii')

        self.iso.rm_directory(iso_path)

        return False


def main():
    """
    The main function.
    """

    if len(sys.argv) != 2:
        print('Usage: %s <isofile>' % (sys.argv[0]))
        sys.exit(1)

    iso = pycdlib.PyCdlib()
    with open(sys.argv[1], 'r+b') as fp:
        iso.open_fp(fp)

        done = False
        cmdloop = PyCdlibCmdLoop(iso)
        while not done:
            try:
                cmdloop.cmdloop()
                done = True
            except Exception as e:  # pylint: disable=broad-except
                print(e)

        iso.close()


if __name__ == '__main__':
    main()
