text: # The MIT License (MIT)
  #
  # Copyright (c) 2019 Niklas Rosenstein
  #
  # 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.
  
  """
  A command-line tool to switch between several Git profiles. Switching to a
  profile will load configuration options from a Git configuration file and
  write them to the current repository.
  """
  
  import argparse
  import base64
  import configparser
  import enum
  import json
  import os
  import subprocess
  import sys
  import typing as t
  from pathlib import Path
  from shlex import quote
  
  import nr.fs
  from databind.core import datamodel, field
  from databind.json import from_json, to_json
  
  from ._vendor.gitconfigparser import GitConfigParser
  
  __author__ = 'Niklas Rosenstein <rosensteinniklas@gmail.com>'
  __version__ = '1.1.2'
  
  
  def git(*args):
    command = 'git ' + ' '.join(map(quote, args))
    return subprocess.check_output(command, shell=True).decode().strip()
  
  
  def find_git_dir():
    directory = os.getcwd()
    prev = None
    while True:
      path = os.path.join(directory, '.git')
      if os.path.exists(path):
        if os.path.isfile(path):
          with open(path) as fp:
            for line in fp:
              if line.startswith('gitdir:'):
                return line.replace('gitdir:', '').strip()
          raise RuntimeError('unable to find gitdir in "{}"'.format(path))
        return path
      directory = os.path.dirname(directory)
      if directory == prev:
        return None
      prev = directory
    return os.path.join(directory, '.git')
  
  
  @datamodel
  class Change:
    type: 'ChangeType'
    section: str
    key: t.Optional[str]
    value: t.Optional[str]
  
  
  class ChangeType(enum.Enum):
    NEW = enum.auto()
    SET = enum.auto()
    DEL = enum.auto()
  
  
  @datamodel
  class Changeset:
    changes: t.List[Change] = field(default_factory=list)
  
    @classmethod
    def from_b64(cls, data: bytes) -> 'Changeset':
      return Changeset(from_json(t.List[Change], json.loads(base64.b64decode(data).decode('utf8'))))
  
    def to_b64(self) -> bytes:
      return base64.b64encode(json.dumps(to_json(self.changes, t.List[Change])).encode('utf8'))
  
    def revert(self, config: configparser.RawConfigParser) -> None:
      for change in reversed(self.changes):
        if change.type == ChangeType.NEW:
          if change.key is None:
            config.remove_section(change.section)
          else:
            config.remove_option(change.section, change.key)
        elif change.type == ChangeType.SET or change.type == ChangeType.DEL:
          assert change.section and change.key and change.value, change
          config.set(change.section, change.key, change.value)
        else:
          raise RuntimeError('unexpected Change.type: {!r}'.format(change))
  
    def set(self, config: configparser.RawConfigParser, section: str, key: str, value: str) -> None:
      if not config.has_section(section):
        config.add_section(section)
        self.changes.append(Change(ChangeType.NEW, section, None, None))
      if not config.has_option(section, key):
        self.changes.append(Change(ChangeType.NEW, section, key, None))
      else:
        self.changes.append(Change(ChangeType.SET, section, key, config.get(section, key)))
      config.set(section, key, value)
  
  
  class MergeReadConfig:
  
    def __init__(self, configs):
      self.configs = configs
  
    def __getattr__(self, name):
      return getattr(self.configs[0], name)
  
    def get(self, section, option, **kwargs):
      fallback = kwargs.pop('fallback', NotImplemented)
      for cfg in self.configs:
        try:
          return cfg.get(section, option, **kwargs)
        except configparser.NoOptionError:
          pass
      if fallback is not NotImplemented:
        return fallback
      raise configparser.NoOptionError((section, option))
  
  
  def main(argv: t.Optional[t.List[str]] = None, prog: t.Optional[str] = None) -> int:
    parser = argparse.ArgumentParser(prog=prog)
    parser.add_argument('profile', nargs='?', help='The name of the profile to use.')
    parser.add_argument('-d', '--diff', action='store_true', help='Print the config diff.')
    args = parser.parse_args(argv)
  
    global_config = GitConfigParser(os.path.expanduser('~/.gitconfig'))
    profiles = set(x.split('.')[0] for x in global_config.sections() if '.' in x and ' ' not in x)
    profiles.add('default')
  
    git_dir = find_git_dir()
    if not git_dir:
      print('fatal: GIT_DIR not found', file=sys.stderr)
      return 1
  
    local_config_fn = os.path.join(git_dir, 'config')
    assert os.path.isfile(local_config_fn), local_config_fn
    local_config = GitConfigParser(local_config_fn, read_only=False)
    current_profile = local_config.get_value('profile', 'current', 'default')
    current_config_text = Path(local_config_fn).read_text()
  
    if not args.profile:
      for x in sorted(profiles, key=lambda x: x.lower()):
        print('*' if x == current_profile else ' ', x)
      return 0
    else:
      if args.profile not in profiles:
        print('fatal: no such profile: "{}"'.format(args.profile), file=sys.stderr)
        return 1
  
      config = MergeReadConfig([local_config, global_config])
      changeset: str = local_config.get_value('profile', 'changeset', '')
      if changeset:
        changes = Changeset.from_b64(changeset.encode('ascii'))
        changes.revert(config)  # type: ignore
  
      if args.profile != 'default':
        changes = Changeset()
        for section in global_config.sections():
          if section.startswith(args.profile + '.'):
            key = section.split('.', 1)[1]
            for opt in global_config.options(section):
              changes.set(config, key, opt, global_config.get(section, opt))  # type: ignore
        changes.set(local_config, 'profile', 'current', args.profile)
        changes.set(local_config, 'profile', 'changeset', changes.to_b64().decode('ascii'))
  
      local_config.write()
      del local_config
  
      if args.diff and Path(local_config_fn).read_text() != current_config_text:
        with nr.fs.tempfile('_old', text=True) as a:
          a.write(current_config_text)
          a.close()
          print()
          subprocess.call(['git', 'diff', '--no-index', a.name, local_config_fn])
          print()
  
      print('Switched to profile "{}".'.format(args.profile))
      return 0
  
  
  if __name__ == '__main__':
    sys.exit(main())
  