#!/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
"""

'''
https://www.python.org/dev/peps/pep-0289/
Node checking:
((0,0),Direction.NORTH) in planetmap[0]
Simplify this for node search:
next(x for (x, y), direction in planetmap[0])
next(y for x, y in planetmap[0] if x == (0, 0))
planetmap[0][next((x, y) for x, y in planetmap[0] if y == 'North')]
'''

#Contains the representation of the map and provides certain functions to manipulate it according to the specifications
class Planet:
    def __init__(self):
        """ Initializes the data structure """
        self._planetmap = {}
        self.target = None

    #Adds a bidirectional path defined between the start and end coordinates to the map and assigns the weight to it.
    def add_path(self, start: Tuple[Tuple[int, int], Direction], target: Tuple[Tuple[int, int], Direction], weight: int):
        if(start[0] not in self._planetmap):
            self._planetmap[start[0]] = {}
        if(start[1] not in self._planetmap[start[0]]):
            self._planetmap[start[0]][start[1]] = (target[0], target[1], weight)
        if(target[0] not in self._planetmap):
            self._planetmap[target[0]] = {}
        if(target[1] not in self._planetmap[target[0]]):
            self._planetmap[target[0]][target[1]] = (start[0], start[1], weight)

    def get_paths(self) -> Dict[Tuple[int, int], Dict[Direction, Tuple[Tuple[int, int], Direction, Weight]]]:
        return self._planetmap

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