assembly.py

from itertools import count
from collections import namedtuple
from abc import ABC, abstractmethod


class BaseAssembler(ABC):
    Result = namedtuple("Result", ["result", "finished"])

    def __init__(self, lines, registers, print_idxs=None):
        self.lines = lines
        self.instrs = self.process_lines(lines)
        self.registers = registers
        self.print_idxs = set() if print_idxs is None else print_idxs

        self.step = -1
        self.instr_idx = 0
        self.instr_idx_delta = 1
        self.jump = None
        self.jump_abs = False

    @abstractmethod
    def is_finished(self):
        pass

    @abstractmethod
    def get_result(self):
        pass

    @classmethod
    def get_possible_instrs(cls):
        return [e[3:] for e in dir(cls) if e.startswith("i__")]

    def print_state(self):
        print(
            f"{self.step:10} | {self.instr_idx:3} "
            + str(" ".join(str(e) for e in self.instrs[self.instr_idx])).ljust(20)
            + " | "
            + " ".join(f"{k}: {v:<10}" for k, v in sorted(self.registers.items()))
        )

    def process_line(self, line):
        return [
            int(e) if e.isdigit() or (e.startswith("-") and e[1:].isdigit()) else e
            for e in line.split()
        ]

    def process_lines(self, lines):
        return [self.process_line(e) for e in lines]

    def is_paused(self):
        return False

    def get_cmd_and_args(self):
        cmd, *args = self.instrs[self.instr_idx]
        return cmd, args

    def eval(self, val):
        return val if isinstance(val, int) else self.registers[val]

    def update_instr_idx(self):
        if self.jump is not None:
            if self.jump_abs:
                self.instr_idx = self.jump
            else:
                self.instr_idx += self.jump
            self.jump = None
            return
        self.instr_idx += self.instr_idx_delta

    def run(self):
        for self.step in count(self.step + 1):
            if self.instr_idx in self.print_idxs:
                self.print_state()

            if self.is_finished():
                return BaseAssembler.Result(self.get_result(), True)

            if self.is_paused():
                return BaseAssembler.Result(self.get_result(), False)

            cmd, args = self.get_cmd_and_args()
            fn = getattr(self, f"i__{cmd}")
            fn(*args)

            self.update_instr_idx()