#!/usr/bin/env python3

from enum import IntEnum, unique
from typing import List, Optional, Tuple, Dict
# IMPORTANT NOTE: DO NOT IMPORT THE ev3dev.ev3 MODULE IN THIS FILE


@unique
class Direction(IntEnum):
    """ Directions in degrees """
    NORTH = 0
    EAST  = 90
    SOUTH = 180
    WEST  = 270


# simple alias, no magic here
Weight = int
""" 
    Weight of a given path (received from the server)
    value:  -1 if broken path 
            >0 for all other paths
            never 0
"""


class Planet:
    """ 
    Contains the representation of the map and provides certain functions to manipulate it according to the specifications 
    """

    def __init__(self):
        """ Initializes the data structure """
        self.target = None

    def add_path(self, start: Tuple[Tuple[int, int], Direction], target: Tuple[Tuple[int, int], Direction], weight: int):
        """ 
        Adds a bidirectional path defined between the start and end coordinates to the map and assigns the weight to it 

        example: 
            add_path(((0, 3), Direction.NORTH), ((0, 3), Direction.WEST), 1)
        """
        pass

    def get_paths(self) -> Dict[Tuple[int, int], Dict[Direction, Tuple[Tuple[int, int], Direction, Weight]]]:
        """ 
        Returns all paths 

        example: 
            get_paths() returns: { 
                                    (0, 3): {
                                                Direction.NORTH: ((0, 3), Direction.WEST, 1), 
                                                Direction.EAST: ((1, 3), Direction.WEST, 2) 
                                            },
                                    (1, 3): {
                                                Direction.WEST: ((0, 3), Direction.EAST, 2), 
                                                ... 
                                            }, 
                                    ...
                                  }
        """
        pass

    def shortest_path(self, start: Tuple[int, int], target: Tuple[int, int]) -> Optional[List[Tuple[Tuple[int, int], Direction]]]:
        """ 
        Returns a shortest path between two nodes 

        examples: 
            shortest_path((0,0), (2,2)) returns: [((0, 0), Direction.EAST), ((1, 0), Direction.NORTH)]
            shortest_path((0,0), (1,2)) returns: None
        """
        pass