hooke/plugin/engine.py

   1 # Copyright
   2
   3 """The `engine` module provides :class:`EnginePlugin` and several
   4 associated :class:`hooke.command.Command`\s for basic
   5 :class:`~hooke.hooke.Hooke` and :class:`~hooke.engine.CommandEngine`
   6 interaction.
   7 """
   8
   9 from ..command import CommandExit, Exit, Command, Argument
  10 from ..interaction import BooleanRequest
  11 from . import Builtin
  12
  13
  14 class EnginePlugin (Builtin):
  15     def __init__(self):
  16         super(EnginePlugin, self).__init__(name='engine')
  17         self._commands = [
  18             ExitCommand(self), HelpCommand(self)]
  19
  20
  21 class ExitCommand (Command):
  22     """Exit Hooke cleanly.
  23     """
  24     def __init__(self, plugin):
  25         super(ExitCommand, self).__init__(
  26             name='exit',
  27             arguments = [
  28                 Argument(name='force', type='bool', default=False,
  29                          help="""
  30 Exit without prompting the user.  Use if you save often or don't make
  31 typing mistakes ;).
  32 """.strip()),
  33                 ],
  34              help=self.__doc__, plugin=plugin)
  35
  36     def _run(self, hooke, inqueue, outqueue, params):
  37         """Exit Hooke, prompting if there are unsaved changes.
  38         """
  39         _exit = True
  40         if params['force'] == False:
  41             not_saved = [p.name for p in hooke.playlists
  42                          if p.is_saved() == False]
  43             msg = 'Exit?'
  44             default = True
  45             if len(not_saved) > 0:
  46                 msg = 'Unsaved playlists (%s).  %s' \
  47                     % (', '.join([str(p) for p in not_saved]), msg)
  48                 default = False
  49             outqueue.put(BooleanRequest(msg, default))
  50             result = inqueue.get()
  51             assert result.type == 'boolean'
  52             _exit = result.value
  53             if _exit == False:
  54                 return
  55             # TODO: check for unsaved config file
  56         if _exit == True:
  57             raise Exit()
  58
  59
  60 class HelpCommand (Command):
  61     """Called with an argument, prints that command's documentation.
  62
  63     With no argument, lists all available help topics as well as any
  64     undocumented commands.
  65     """
  66     def __init__(self, plugin):
  67         super(HelpCommand, self).__init__(
  68             name='help', help=self.__doc__, plugin=plugin)
  69         # We set .arguments now (vs. using th arguments option to __init__),
  70         # to overwrite the default help argument.  We don't override
  71         # :meth:`cmd.Cmd.do_help`, so `help --help` is not a valid command.
  72         self.arguments = [
  73             Argument(name='command', type='string', optional=True,
  74                      help='The name of the command you want help with.')
  75             ]
  76
  77     def _run(self, hooke, inqueue, outqueue, params):
  78         if params['command'] == None:
  79             outqueue.put(sorted([c.name for c in hooke.commands]))
  80         else:
  81             outqueue.put(hooke.command_by_name[params['command']].help())