from typing import Any
from uuid import UUID

from api.od import ODAPI
from transformation.matcher import match_od
from transformation.rewriter import rewrite
from util.loader import parse_and_check


class RuleExecutor:
    def __init__(self, state, mm: UUID, mm_ramified: UUID, eval_context={}):
        self.state = state
        self.mm = mm
        self.mm_ramified = mm_ramified
        self.eval_context = eval_context

    # Generates matches.
    # Every match is a dictionary with entries LHS_element_name -> model_element_name
    def match_rule(self, m: UUID, lhs: UUID, *, pivot: dict[Any, Any]):
        lhs_matcher = match_od(
            self.state,
            host_m=m,
            host_mm=self.mm,
            pattern_m=lhs,
            pattern_mm=self.mm_ramified,
            eval_context=self.eval_context,
            pivot=pivot,
        )
        return lhs_matcher

    def rewrite_rule(self, od: ODAPI, rhs: UUID, *, pivot: dict[Any, Any]):
        rhs = rewrite(
            self.state,
            rhs_m=rhs,
            pattern_mm=self.mm_ramified,
            lhs_match=pivot,
            host_m=od.m,
            host_mm=od.mm,
            eval_context=self.eval_context,
        )
        od.recompute_mappings()
        yield rhs

    def load_match(self, file: str):
        with open(file, "r") as f:
            return parse_and_check(self.state, f.read(), self.mm_ramified, file)