from core.concept import ReturnValueConcept, ErrorConcept
from evaluators.BaseEvaluator import BaseEvaluator
from parsers.PythonParser import PythonNode
import ast
from core.sheerka import ReturnValue, Sheerka
import logging

log = logging.getLogger(__name__)


class PythonEvaluator(BaseEvaluator):
    def __init__(self):
        super().__init__("Python Evaluator", 50)

    def matches(self, context, items):
        return len(items) == 1 and isinstance(items[0].value, PythonNode)

    def eval(self, context, items):
        sheerka = context.sheerka
        node = items[0].value
        if isinstance(node.ast, ast.Expression):
            try:
                log.debug("Evaluating python expression")
                compiled = compile(node.ast, "<string>", "eval")
                evaluated = eval(compiled, {}, {"sheerka": context.sheerka})
                concept = sheerka.new(ReturnValueConcept.NAME, body=evaluated)
                return ReturnValue(self.name, True, concept)
            except Exception as error:
                error = sheerka.new(ErrorConcept.NAME, body=error)
                return ReturnValue(self.name, False, error)
        else:
            raise NotImplementedError()