def _potential_nodes_from(self, node: Node) -> Iterator[Tuple[Node, Requirement, bool]]:
extra_requirement = _extra_requirement_for_node(self._game, node)
requirement_to_leave = node.requirement_to_leave(self._state.patches, self._state.resources)
for target_node, requirement in self._game.world_list.potential_nodes_from(node, self.state.patches):
if target_node is None:
continue
if requirement_to_leave != Requirement.trivial():
requirement = RequirementAnd([requirement, requirement_to_leave])
if extra_requirement is not None:
requirement = RequirementAnd([requirement, extra_requirement])
satisfied = requirement.satisfied(self._state.resources, self._state.energy)
yield target_node, requirement, satisfied
def calculate_reach(cls,
logic: Logic,
initial_state: State) -> "ResolverReach":
checked_nodes: Dict[Node, int] = {}
# Keys: nodes to check
# Value: how much energy was available when visiting that node
nodes_to_check: Dict[Node, int] = {
initial_state.node: initial_state.energy
}
reach_nodes: Dict[Node, int] = {}
requirements_by_node: Dict[Node, Set[RequirementList]] = defaultdict(set)
path_to_node: Dict[Node, Tuple[Node, ...]] = {}
path_to_node[initial_state.node] = tuple()
while nodes_to_check:
node = next(iter(nodes_to_check))
energy = nodes_to_check.pop(node)
if node.heal:
energy = initial_state.maximum_energy
checked_nodes[node] = energy
if node != initial_state.node:
reach_nodes[node] = energy
requirement_to_leave = node.requirement_to_leave(initial_state.patches, initial_state.resources)
for target_node, requirement in logic.game.world_list.potential_nodes_from(node, initial_state.patches):
if target_node is None:
continue
if checked_nodes.get(target_node, math.inf) <= energy or nodes_to_check.get(target_node,
math.inf) <= energy:
continue
if requirement_to_leave != Requirement.trivial():
requirement = RequirementAnd([requirement, requirement_to_leave])
# Check if the normal requirements to reach that node is satisfied
satisfied = requirement.satisfied(initial_state.resources, energy)
if satisfied:
# If it is, check if we additional requirements figured out by backtracking is satisfied
satisfied = logic.get_additional_requirements(node).satisfied(initial_state.resources,
energy)
if satisfied:
nodes_to_check[target_node] = energy - requirement.damage(initial_state.resources)
path_to_node[target_node] = path_to_node[node] + (node,)
elif target_node:
# If we can't go to this node, store the reason in order to build the satisfiable requirements.
# Note we ignore the 'additional requirements' here because it'll be added on the end.
requirements_by_node[target_node].update(requirement.as_set.alternatives)
# Discard satisfiable requirements of nodes reachable by other means
for node in set(reach_nodes.keys()).intersection(requirements_by_node.keys()):
requirements_by_node.pop(node)
if requirements_by_node:
satisfiable_requirements = frozenset.union(
*[RequirementSet(requirements).union(logic.get_additional_requirements(node)).alternatives
for node, requirements in requirements_by_node.items()])
else:
satisfiable_requirements = frozenset()
return ResolverReach(reach_nodes, path_to_node,
satisfiable_requirements,
logic)