from arpeggio.cleanpeg import ParserPEG
from typing import List, Union
import arpeggio

from . import grammar, JobShopProblem, JobShopVisitor


class JobShop1Visitor(JobShopVisitor):
    """instanciated for semantic analysis of parse_tree"""

    def visit_problem_instance(
            self, node: arpeggio.ParseTreeNode,
            children: arpeggio.SemanticActionResults) -> JobShopProblem:
        if self.debug:
            print("problem_instance\nchildren:", children)
        problem: JobShopProblem = children[3]
        problem.name = children[0]
        problem.description = children[2]
        return problem

    def visit_instance_list(
            self, node: arpeggio.ParseTreeNode,
            children: arpeggio.SemanticActionResults) -> List[JobShopProblem]:
        if self.debug:
            print("instance_list\nchildren:", children)
        return list(filter(lambda x: isinstance(x, JobShopProblem), children))

    def visit_skip_preface(
            self, node: arpeggio.ParseTreeNode,
            children: arpeggio.SemanticActionResults) -> List[JobShopProblem]:
        if self.debug:
            print("skip_preface\nchildren:", children)
        return list(filter(lambda x: type(x) is list, children))[0]

    # ignore eol nodes
    def visit_eol(
            self, node: arpeggio.ParseTreeNode,
            children: arpeggio.SemanticActionResults) -> None:
        return None

    # ignore trim_ws nodes
    def visit_trim_ws(
            self, node: arpeggio.ParseTreeNode,
            children: arpeggio.SemanticActionResults) -> None:
        return None


def parse_string(inputdata: str) -> JobShopProblem:
    """parse string with jobshop1-formatted data (multiple problem instances)
    and return list of JobShopProblem s"""
    parse_tree = parser.parse(inputdata)
    return arpeggio.visit_parse_tree(parse_tree, JobShop1Visitor())


def parse_file(filename: Union[str, bytes]) -> List[JobShopProblem]:
    """Open file with jobshop1-formatted data (multiple problem instances),
    parse it and return list of JobShopProblem s"""

    with open(filename) as datafile:
        inputdata: str = datafile.read()
        return parse_string(inputdata)


def main():
    print(parse_file("../inputdata/jobshop1.txt"))


parser = ParserPEG(grammar, "job_shop1", skipws=False)

if __name__ == "__main__":
    main()