5599bd73b2d724e6986bc8a58d3ecf7e3ba2da16
[naja.git] / naja / actions.py
1 from naja.constants import BITS
2
3
4 class LocationAction(object):
5     """
6     An action that may be performed on a location.
7     """
8
9     TEXT = None
10
11     def __init__(self, required_bits, **data):
12         self.required_bits = frozenset(required_bits)
13         self.data = data
14
15     def check_available(self, player):
16         return player.bits.check_bits(self.required_bits)
17
18     def perform_action(self, board, location):
19         raise NotImplementedError("TODO")
20
21     def check_and_clear_MSB(self, player):
22         if player.bits.check_bit(BITS.MSB):
23             player.bits.clear_bit(BITS.MSB)
24             return True
25         else:
26             return False
27
28
29 class DoNothing(LocationAction):
30     TEXT = "No effect."
31
32     def perform_action(self, board, location):
33         pass
34
35
36 class LoseHeathOrMSB(LocationAction):
37     TEXT = "Lose health. If MSB is set, it will be cleared instead."
38
39     def perform_action(self, board, location):
40         if not self.check_and_clear_MSB(board.player):
41             board.lose_health()
42
43
44 class SetBits(LocationAction):
45     TEXT = "Set bits specified by this location."
46
47     def perform_action(self, board, location):
48         board.player.bits.set_bits(location.bitwise_operand)
49
50
51 class ToggleBits(LocationAction):
52     TEXT = "Toggle bits specified by this location."
53
54     def perform_action(self, board, location):
55         board.player.bits.toggle_bits(location.bitwise_operand)