from py_trees.behaviour import Behaviour
from py_trees.common import Status
from constants import TIMEOUT, JAR_OFFSETS
from setup import blackboard, robot, gps, compass, camera
from utilities import robot_to_world_coords, grasp_point
from numpy import arctan2

# Detect the jar using the camera and store its position in the blackboard.
class JarFinder(Behaviour):
    def __init__(self, name, target_jar, jar_offset):
        super().__init__(name)
        self.target_jar = target_jar
        self.offset = jar_offset

    def initialise(self):
        self.initial_time = robot.getTime()
        print("%s.initialise(), targeting %s" % (self.name, self.target_jar))

    def update(self):
        if robot.getTime() - self.initial_time > TIMEOUT:
            print(
                "%s.update()[%s->%s], Timed out"
                % (self.name, self.status, Status.FAILURE)
            )
            return Status.FAILURE

        gps_pos = gps.getValues()
        theta = arctan2(*compass.getValues()[:2])
        for jar in camera.getRecognitionObjects():
            print("%s.update(), %s detected." % (self.name, jar.getModel()))
            if jar.getModel() == self.target_jar:
                jar_pos = robot_to_world_coords(jar.getPosition(), gps_pos, theta)
                blackboard["target_pos"] = grasp_point(jar_pos, gps_pos, self.offset)
                print(
                    "%s.update()[%s->%s], jar at [%.3f, %.3f]"
                    % (self.name, self.status, Status.SUCCESS, *jar_pos)
                )
                return Status.SUCCESS
        print(
            "%s.update()[%s->%s], %s not found yet."
            % (self.name, self.status, self.target_jar, Status.RUNNING)
        )
        return Status.RUNNING