Files
ProgressQuest-cli/pqcli/random.py
T
Dash fd4a7d151d misc: replace Any with precise types
Curses screens, windows and pads are typed as curses.window, and the
widgets that may get no parent window take curses.window | None.

- EventHandler is generic over a ParamSpec, so each handler declares
  the arguments it passes, and MenuView is generic over the item its
  on_confirm hands out. Choice callbacks take no arguments.
- Scrollable is generic over its items, which DataTable and ListBox
  fix to tuple[str, str] and str.
- random.choice() and choice_low() are generic over the sequence, so
  the casts at their call sites are gone. BasicUserInterface.menu()
  and util.first() are generic too.
- Signal callbacks and their payloads are Callable[..., object] and
  object, since emit() only forwards them.
- JSON values in game_data are object and narrowed by isinstance,
  and data files are Traversable.
- Signal handlers take an int and a FrameType | None, and
  list_players() takes a TextIO.
- The focus_standout() context managers return
  Generator[None, None, None].

Any remains in three places: Player.__setstate__, whose pickled
__dict__ holds values of every type; Focusable.__init__, a mixin that
passes *args and **kwargs through to the next class; and the values
load_game_data() collects, whose element type depends on the field
each one fills.
2026-10-17 15:55:59 +02:00

125 lines
3.0 KiB
Python

import contextlib
import time
from collections.abc import Callable, Generator, Sequence
from typing import TypeVar
RngState = tuple[float, float, float, int]
T = TypeVar("T")
_2_POW_32 = 0x100000000
_2_POW_MINUS_32 = 2.3283064365386963e-10
def _to_uint32(value: float) -> float:
# JS `value >>> 0` for the non-negative values Mash produces
return float(int(value) % _2_POW_32)
def _mash() -> Callable[[str], float]:
n = float(0xEFC8249D)
def mash(data: str) -> float:
nonlocal n
# JS strings are UTF-16, and charCodeAt() returns code units
units = data.encode("utf-16-le")
for i in range(0, len(units), 2):
n += units[i] | (units[i + 1] << 8)
h = 0.02519603282416938 * n
n = _to_uint32(h)
h -= n
h *= n
n = _to_uint32(h)
h -= n
n += h * _2_POW_32
return _to_uint32(n) * _2_POW_MINUS_32
return mash
class Alea:
"""Johannes Baagøe's Alea PRNG (MIT), as used by Progress Quest web.
Ported bit for bit so that games seeded alike play out alike. Saves
pickle this class by import path, so it must stay in this module.
"""
def __init__(self, *args: str) -> None:
if not args:
args = (str(int(time.time() * 1000)),)
mash = _mash()
self._s0 = mash(" ")
self._s1 = mash(" ")
self._s2 = mash(" ")
self._c = 1
for arg in args:
self._s0 -= mash(arg)
if self._s0 < 0:
self._s0 += 1
self._s1 -= mash(arg)
if self._s1 < 0:
self._s1 += 1
self._s2 -= mash(arg)
if self._s2 < 0:
self._s2 += 1
@classmethod
def from_state(cls, state: RngState) -> "Alea":
rng = cls.__new__(cls)
rng._s0, rng._s1, rng._s2, rng._c = state
return rng
def state(self) -> RngState:
return (self._s0, self._s1, self._s2, self._c)
def random(self) -> float:
t = 2091639 * self._s0 + self._c * _2_POW_MINUS_32
self._s0 = self._s1
self._s1 = self._s2
self._c = int(t)
self._s2 = t - self._c
return self._s2
def uint32(self) -> int:
return int(self.random() * _2_POW_32)
_current = Alea()
def seed(source: str) -> None:
global _current
_current = Alea(source)
@contextlib.contextmanager
def using(rng: Alea) -> Generator[None, None, None]:
"""Draw from rng instead of the shared generator inside the block."""
global _current
previous = _current
_current = rng
try:
yield
finally:
_current = previous
def choice(source: Sequence[T]) -> T:
return source[below(len(source))]
def choice_low(source: Sequence[T]) -> T:
return source[below_low(len(source))]
def below(num: int) -> int:
return _current.uint32() % num
def below_low(num: int) -> int:
return min(below(num), below(num))
def odds(chance: int, out_of: int) -> bool:
return below(out_of) < chance