"""
Directives for explicitly modifying the program memory.
"""

from abc import ABC, abstractmethod
from collections import deque

class AbstractDirective(ABC):
	@abstractmethod
	def parse(self, assembler, tokenizer):
		"""
		Parse the directive by converting the text to a list of words.
		Returns a list of 16bit words.
		"""
		pass



class SetDirective(AbstractDirective):
	def parse(self, assembler, tokenizer):
		words = deque()
		should_be_bracket = next(tokenizer)
		if(not should_be_bracket == "["):
			assembler.raise_unexpected_token(".set", "'['", should_be_bracket)

		while(True):
			should_be_value = next(tokenizer)
			if(not can_convert_to_int(should_be_value)):
				assembler.raise_unexpected_token(".set"
						, "integer or character value"
						, should_be_value)
			words.append(autoint(should_be_value))

			comma_or_bracket = next(tokenizer)
			if(not comma_or_bracket in (",", "]")):
				assembler.raise_unexpected_token(".set"
						, "',' or ']'"
						, comma_or_bracket)

			if(comma_or_bracket == "]"):
				break
		return list(words)