Piet_interpreter/interpreter/executeFunctions.py
2020-05-09 12:53:26 +02:00

113 lines
4.1 KiB
Python

import copy
from typing import Union, List, Callable
import numpy as np
from interpreter import imageFunctions as imageWrapper
from interpreter import lexer as lexer
from interpreter import tokens as tokens
from interpreter import movementFunctions as movement
from interpreter import colors as colors
from interpreter import tokenFunctions as runner
from interpreter import errors as errors
from interpreter.dataStructures import programState, position, direction
def interpret(image: np.ndarray) -> Union[programState, List[BaseException]]:
"""
Interprets and executes a Piet image
:param image: Input image
:return: Either the final state of the program, or a list of exceptions
"""
graph = lexer.graphImage(image)
if len(graph[1]) > 0:
print("The following exceptions occured while making the graph:\n{}".format("".join(list(map(lambda x: "\t{}\n".format(x), graph[1])))))
return graph[1]
# This is the default programState.
startPosition = position((0, 0))
pointers = direction((0, 0))
PS = programState(graph[0], startPosition, pointers)
result = runProgram(image, PS)
# Check if executed step had an error
if isinstance(result, BaseException):
print("The following exception occured while executing the next step:\n{}".format(result))
return [result]
return result
def runProgram(image: np.ndarray, PS: programState) -> Union[programState, BaseException]:
"""
Executes all steps from the image
:param image: input image
:param PS: current program state with which to make the next step
:return: Either the last program state, or a runtime exception
"""
newState = copy.deepcopy(PS)
if colors.isBlack(imageWrapper.getPixel(image, newState.position)):
return errors.inBlackPixelError("Programstate starts in black pixel at {}".format(newState.position))
currentCodel = imageWrapper.getCodel(image, newState.position)
newGraph = newState.graph.graph
graphNode = newGraph[currentCodel]
newToken = graphNode.graphNode[newState.direction][0]
if isinstance(newToken, tokens.terminateToken):
return newState
newState = takeStep(image, newState)
if isinstance(newState, BaseException):
return newState
return runProgram(image, newState)
def countSteps(f: Callable[[np.ndarray, programState], programState]) -> Callable[[np.ndarray, programState], programState]:
"""
A decorator function to count the steps taken in the program
:param f: original function to call
:return: A decorated function
"""
def inner(image: np.ndarray, PS: programState) -> programState:
inner.counter += 1
return f(image, PS)
inner.counter = 0
return inner
@countSteps
def takeStep(image: np.ndarray, PS: programState) -> Union[programState, BaseException]:
"""
Takes a single step from the programstate
:param image: input image
:param PS: input programstate
:return: Returns either the resulting programstate, or an exception that occurred
"""
newState = copy.deepcopy(PS)
currentCodel = imageWrapper.getCodel(image, newState.position)
newGraph = newState.graph.graph
graphNode = newGraph[currentCodel]
newToken = graphNode.graphNode[newState.direction][0]
edgePosition = graphNode.graphNode[newState.direction][1]
result = runner.executeToken(newToken, newState.direction, newState.dataStack)
# Add additional information to the error message (Position and direction)
if isinstance(result, BaseException):
return type(result)("{}, at position {}, direction {}".format(result.args[0], edgePosition,newState.direction))
# return result
# If the next token is either white or color, just move along. If the token was black (or terminate), the direction
# is already changed, but the position shouldn't move
if isinstance(newToken, (tokens.toWhiteToken, tokens.toColorToken)):
newState.position = movement.getNextPosition(edgePosition, newState.direction.pointers[0])
# Use the new direction and stack for the next step
newState.direction = result[0]
newState.dataStack = result[1]
return newState