class AStarGAC:
def __init__(self):
# Keep track of all the nodes in the system
self.nodes = []
# Set node type for AStar
AStar.State = GACState
# Reference to AStar and CSP
self.astar = AStar()
self.gac_state = None
# Set behavior
self.astar.set_behavior(BestFirst)
def start(self):
# Run CSP-initialize and CSP-domain-filtering-loop
self.gac_state.gac.initialize()
self.gac_state.gac.domain_filtering()
# Assign the current state to AStar and begin to solve
self.astar.states[self.gac_state.get_hash()] = self.gac_state
self.astar.behavior.add(self.gac_state, self.astar.open)
# Check if we are finished or if the current state is invalid
if self.gac_state.gac.check_finished() or self.gac_state.gac.check_contradictory_state():
if self.gac_state.gac.check_finished():
# We found the solution without actually running the agenda loop, make sure we save goal state
self.gac_state.type = self.astar.State.GOAL
return True
return False
def run(self):
if self.gac_state.gac.check_finished():
return True
# Do one step in the agenda loop
finished = self.astar.agenda_loop()
# Update the CSP state
self.gac_state = self.astar.closed[-1]
# Return the result from the agenda loop
return finished
