import numpy as np
from retro.views.headless import HeadlessView
from retro_gamer.observation import egocentric_board, encode_board, encode_state

CHARACTER_SET = ["@", "*", ">", "<", "^", "v"]
RADIUS = 8


def egocentric_observation(game):
    """17×17 window centered on the snake's head, plus apple_dx and apple_dy."""
    view = HeadlessView()
    view.on_game_start(game)
    view.render(game)
    head = game.get_agent_by_name("Snake head")
    cropped = egocentric_board(view.board_characters, head.position, RADIUS)
    board_vec = encode_board(cropped, CHARACTER_SET).flatten()
    extras = encode_state(game.state, ["apple_dx", "apple_dy"])
    return np.concatenate([board_vec, extras])