Files
dopey/dopey.py
2021-06-16 20:27:16 -04:00

141 lines
4.0 KiB
Python

import sys
from typing import Dict, List
class MismatchBracketException(Exception):
""" TODO line number and column """
pass
class MemoryException(Exception):
""" TODO line number and column """
pass
class Memory:
BUFFER_SIZE = 30_000
buffer = [0 for _ in range(BUFFER_SIZE)]
pointer = 0
input_buffer = []
@classmethod
def get_pointer(cls) -> int:
return cls.pointer
class Operation:
SHIFT_LEFT = "<"
SHIFT_RIGHT = ">"
INCREMENT = "+"
DECREMENT = "-"
OUTPUT = "."
INPUT = ","
OPEN_LOOP = "["
CLOSE_LOOP = "]"
loop_stack = []
loop_ignore_stack = []
@classmethod
def perform(cls, operation: str, program: List, switch: Dict) -> None:
# if operation does not exist, skip
if operation not in switch:
return
# dont perform any non loop operations if inside an ignore loop
if len(cls.loop_ignore_stack) and operation != Operation.CLOSE_LOOP and operation != Operation.OPEN_LOOP:
return
switch[operation](program)
@classmethod
def shift_left(cls, _) -> None:
Memory.pointer -= 1
if Memory.pointer < 0:
raise MemoryException
@classmethod
def shift_right(cls, _) -> None:
Memory.pointer += 1
if Memory.pointer >= Memory.BUFFER_SIZE:
raise MemoryException
@classmethod
def increment(cls, _) -> None:
Memory.buffer[Memory.get_pointer()] += 1
@classmethod
def decrement(cls, _) -> None:
Memory.buffer[Memory.get_pointer()] -= 1
@classmethod
def output(cls, _) -> None:
sys.stdout.write(chr(Memory.buffer[Memory.get_pointer()])) # TODO rollover if too big in ASCII
sys.stdout.flush() # TODO possible performance issue
@classmethod
def input(cls, _) -> None:
if not len(Memory.input_buffer):
input_ = sys.stdin.readline()
Memory.input_buffer += list(input_)
if len(Memory.input_buffer):
Memory.buffer[Memory.get_pointer()] = ord(Memory.input_buffer.pop(0))
@classmethod
def open_loop(cls, program: List) -> None:
if not Memory.buffer[Memory.get_pointer()]:
# enter ignore loop if byte at pointer is zero
cls.loop_ignore_stack.append(Operation.OPEN_LOOP)
else:
# save start loop position should we need to return
cls.loop_stack.append(program[1]-1)
@classmethod
def close_loop(cls, program: List) -> None:
# check if in ignore loop
if len(cls.loop_ignore_stack):
cls.loop_ignore_stack.pop()
return
# check if there is a bracket mismatch
if not len(cls.loop_stack):
raise MismatchBracketException
# check if we need to repeat
last_open_loop_pos = cls.loop_stack.pop()
if Memory.buffer[Memory.get_pointer()]:
program[1] = last_open_loop_pos
def get_operations_in_switch() -> Dict:
return {
Operation.SHIFT_LEFT: Operation.shift_left,
Operation.SHIFT_RIGHT: Operation.shift_right,
Operation.INCREMENT: Operation.increment,
Operation.DECREMENT: Operation.decrement,
Operation.OUTPUT: Operation.output,
Operation.INPUT: Operation.input,
Operation.OPEN_LOOP: Operation.open_loop,
Operation.CLOSE_LOOP: Operation.close_loop
}
def main() -> None:
file_location = None
if len(sys.argv) != 2:
print("Invalid or missing arguments...")
sys.exit()
else:
file_location = sys.argv[1]
file = open(file_location, "r")
program = [file.read(), 0] # TODO create program class
file.close()
switch = Operation.get_operations_in_switch()
while program[1] < len(program[0]):
operation = program[0][program[1]]
program[1] += 1
Operation.perform(operation, program, switch)
if len(Operation.loop_stack):
raise MismatchBracketException
if __name__ == "__main__":
main()