blockgame.vector = blockgame.vector or {}
local api = blockgame.vector

-- TODO: replace direct sharing of api variables such as `sides` with functions that return them, to prevent other mods from mutating the shared data.

api.horizontal_directions = {
	west = vector.new(-1, 0, 0),
	east = vector.new(1, 0, 0),
	south = vector.new(0, 0, -1),
	north = vector.new(0, 0, 1),
}
api.sides = api.horizontal_directions

api.directions = {
	west = vector.new(-1, 0, 0),
	east = vector.new(1, 0, 0),
	down = vector.new(0, -1, 0),
	up = vector.new(0, 1, 0),
	south = vector.new(0, 0, -1),
	north = vector.new(0, 0, 1),
}
api.dirs = api.directions



function api.random_dir ()
	return blockgame.random_element(api.dirs)
end

function api.random_side ()
	return blockgame.random_element(api.sides)
end

function api.get_below (pos)
	return pos + api.dirs.down
end

function api.get_neighbors (pos, neighborhood)
	neighborhood = neighborhood or blockgame.vector.dirs
	local neighbors = {}
	for _, dir in pairs(neighborhood) do
		table.insert(neighbors, pos + dir)
	end
	return neighbors
end

function api.get_sides_of (pos)
	return api.get_neighbors(pos, api.sides)
end