import itertools

from . import SimConcretizationStrategy


class SimConcretizationStrategyNorepeats(SimConcretizationStrategy):
    """
    Concretization strategy that resolves addresses, without repeating.
    """

    def __init__(self, repeat_expr, repeat_constraints=None, **kwargs):
        super().__init__(**kwargs)
        self._repeat_constraints = [] if repeat_constraints is None else repeat_constraints
        self._repeat_expr = repeat_expr

    def _concretize(self, memory, addr, **kwargs):
        child_constraints = tuple(self._repeat_constraints) + (addr == self._repeat_expr,)
        extra_constraints = kwargs.pop("extra_constraints", None)
        if extra_constraints is not None:
            child_constraints += tuple(extra_constraints)
        c = self._any(memory, addr, extra_constraints=child_constraints, **kwargs)
        self._repeat_constraints.append(self._repeat_expr != c)
        return [c]

    def copy(self):
        return SimConcretizationStrategyNorepeats(
            repeat_expr=self._repeat_expr, repeat_constraints=list(self._repeat_constraints), exact=self._exact
        )

    def merge(self, others):
        seen = {s.cache_key for s in self._repeat_constraints}
        for c in itertools.chain.from_iterable(o._repeat_constraints for o in others):
            if c.cache_key not in seen:
                seen.add(c.cache_key)
                self._repeat_constraints.append(c)
