import random
from dataclasses import dataclass

from maze import Cell


@dataclass
class Choice:
    score: int
    cell: Cell

    def __add__(self, other):
        self.score += other

    def __sub__(self, other):
        self.score -= other


class Agent:
    def __init__(self, buffer, grid_size):
        self.location = Cell(0, 0)
        self.last_visited = Cell(0, 0)
        self.buffer = buffer
        self.grid_size = grid_size
        self.first_step = True
        self.auto_finish = 1

    def reset(self):
        self.location = Cell(0, 0)
        self.first_step = True
        self.last_visited = Cell(0, 0)

    def get_x_position(self):
        return (self.location.x * self.grid_size) + self.buffer + self.grid_size / 1.9

    def get_y_position(self):
        return (self.location.y * self.grid_size) + self.buffer + self.grid_size / 1.9

    def move(self, maze):
        if self.first_step:
            self.first_step = False
            return
        # Random Walk
        # self.location = random.choice(maze.maze[self.location])
        # Direct to end
        # _, self.location = min(sorted([(maze.distance_map[x], x) for x in maze.maze[self.location]]))
        # no backstep.
        # self.last_visited = self.location

        # Go to end when close.
        if maze.distance_map[self.location] <= self.auto_finish:
            _, self.location = min(sorted([(maze.distance_map[x], x) for x in maze.maze[self.location]]))
        else:
            choices = maze.maze[self.location].copy()
            try:
                choices.remove(self.last_visited)
            except ValueError:
                pass

            if not choices:
                self.last_visited = self.location
                self.location = maze.maze[self.last_visited][0]
            else:
                if smart_choices := set(choices).difference(maze.dead_ends):

                    self.last_visited = self.location
                    self.location = random.choice(list(smart_choices))
                else:
                    self.last_visited = self.location
                    self.location = random.choice(choices)