"""
Parse the input file
"""

from classes import ParsingMode, Coordinate, LocationType, Location, DataSet


def parse(filename: str) -> DataSet:
    """
    Parse a given file with given format and return a DataSet containing the
    parsed locations, flightschedules and wanted connection
    """
    locations: dict = {}
    flights: dict = {}
    connection: tuple = ()
    with open(filename, "r") as file:
        for line in file.readlines():
            line = line.replace("\n", "")  # strip newline
            line = line.replace(" ", "")  # strip whitespaces

            # skip empty lines
            if line == "":
                continue

            # meta parsing
            match line:
                case "Locations:":
                    print("Parsing `Locations`...")
                    current_parsing = ParsingMode.LOCATIONS
                    continue
                case "FlightSchedule:":
                    print("Parsing `FlightSchedule`...")
                    current_parsing = ParsingMode.FLIGHTSCHEDULE
                    continue
                case "FindBestConnections:":
                    print("Parsing `FindBestConnections`...")
                    current_parsing = ParsingMode.FINDCONNECTION
                    continue

            match current_parsing:
                case ParsingMode.LOCATIONS:
                    print("Parsing location...")
                    splitted = line.split(";")
                    assert(len(splitted) == 6)  # make sure we have a location
                    id = splitted[0]
                    type = splitted[1]
                    match type:
                        case "Location":
                            type = LocationType.LOCATION
                        case "PublicTransportStop":
                            type = LocationType.HALTESTELLE
                        case "Airport":
                            type = LocationType.FLUGHAFEN
                    lat = splitted[2]
                    long = splitted[3]
                    continent = splitted[4]
                    name = splitted[5]
                    coord = Coordinate(lat, long)
                    location = Location(coord, continent, name, type)
                    locations.update({id: location})
                case ParsingMode.FLIGHTSCHEDULE:
                    print("Parsing flight schedule...")
                    splitted = line.split(";")
                    assert(len(splitted) >= 2)
                    id1 = splitted[0]
                    id2 = splitted[1]
                    if len(splitted) == 3:
                        stops = splitted[2]
                    else:
                        stops = 0
                    if len(splitted) == 4:
                        domestic = True
                    else:
                        domestic = False
                    flights.update({id1: {
                                        "to": id2,
                                        "stops": stops,
                                        "domestic": domestic}})
                    continue
                case ParsingMode.FINDCONNECTION:
                    print("Parsing connection...")
                    splitted = line.split(";")
                    assert(len(splitted) == 2)
                    connection = (splitted[0], splitted[1])
    return DataSet(locations, flights, connection)