mirror of
https://github.com/blackboxprogramming/lucidia.git
synced 2026-03-17 05:57:21 -05:00
30 lines
890 B
Python
30 lines
890 B
Python
from __future__ import annotations
|
|
|
|
from dataclasses import dataclass
|
|
from typing import Dict, Callable, Any
|
|
|
|
|
|
@dataclass
|
|
class Transition:
|
|
to_state: str
|
|
guard: Callable[[Dict[str, Any]], bool] | None = None
|
|
|
|
|
|
class StateMachine:
|
|
"""Simple finite state machine with optional guards."""
|
|
def __init__(self, initial: str) -> None:
|
|
self.state = initial
|
|
self.table: Dict[str, Dict[str, Transition]] = {}
|
|
|
|
def add(self, from_state: str, event: str, transition: Transition) -> None:
|
|
self.table.setdefault(from_state, {})[event] = transition
|
|
|
|
def step(self, event: str, ctx: Dict[str, Any]) -> str:
|
|
trans = self.table.get(self.state, {}).get(event)
|
|
if not trans:
|
|
return self.state
|
|
if trans.guard and not trans.guard(ctx):
|
|
return self.state
|
|
self.state = trans.to_state
|
|
return self.state
|