#!/usr/bin/env python
import rospy
import actionlib
import simulation_control.msg
from geometry_msgs.msg import PoseStamped, Point
from std_msgs.msg import Bool, String
'''Object Descend for F651
   Copyright (C) 2018, CPS2018 Challenge by Team Halmstad. All rights reserved.
 '''

class descend_on_object_server():
    def __init__(self):

        #variables
        self.local_pose = PoseStamped()
        self.des_pose = PoseStamped()
        self.object_pose = Point()

        #publishers
        self.mode_control = rospy.Publisher('/position_control/set_mode', String, queue_size=10)
        self.vel_control = rospy.Publisher('/position_control/set_velocity', PoseStamped, queue_size=10)

        #subscribers
        rospy.Subscriber('/color_detection/cam_point', Point, self.get_cam_pos_callback)
        rospy.Subscriber('/mavros/local_position/pose', PoseStamped, self._local_pose_callback)
        rospy.Subscriber('/position_control/distance', Bool, self.distance_reached_cb)

        self.rate = rospy.Rate(20)
        self.result = simulation_control.msg.descend_on_objectResult()
        self.action_server = actionlib.SimpleActionServer('descend_on_object',
                                                            simulation_control.msg.descend_on_objectAction,
                                                             execute_cb=self.execute_cb,
                                                              auto_start=False)
        self.last_object_pose = Point()
        self.action_server.start()


    def execute_cb(self, goal):
        rospy.loginfo("Starting to descend")
        self.mode_control.publish('velctr')
        rospy.sleep(0.1)

        while self.local_pose.pose.position.z > 1.0:
            self.rate.sleep()
            print("x = ",self.local_pose.pose.position.x)
            print("y = ",self.local_pose.pose.position.y)
            print("z = ",self.local_pose.pose.position.z)
            rospy.sleep(0.2)


            if self.detected and (abs(self.object_pose.x) > 0.2 or abs(self.object_pose.y) > 0.2):
                self.last_object_pose = self.object_pose
                self.des_pose.pose.position.x = self.object_pose.x
                self.des_pose.pose.position.y = self.object_pose.y
                self.des_pose.pose.position.z = self.local_pose.pose.position.z
                self.vel_control.publish(self.des_pose)
                rospy.loginfo("Centering...")
                while not self.target_reached:
                    rospy.sleep(2)

            elif self.detected and abs(self.object_pose.x) < 0.2 and abs(self.object_pose.y) < 0.2:
                self.des_pose.pose.position.x = 0
                self.des_pose.pose.position.y = 0
                self.des_pose.pose.position.z = self.local_pose.pose.position.z - 0.9
                rospy.loginfo("Descending...")
                self.vel_control.publish(self.des_pose)
                while not self.target_reached:
                    rospy.sleep(2)

        while self.local_pose.pose.position.z < 1.0 and self.local_pose.pose.position.z > 0.1:
            self.rate.sleep()
            print("x = ",self.local_pose.pose.position.x)
            print("y = ",self.local_pose.pose.position.y)
            print("z = ",self.local_pose.pose.position.z)
            rospy.sleep(0.2)
 
            if self.detected and (abs(self.object_pose.x) > 0.05 or abs(self.object_pose.y) > 0.05):
                self.last_object_pose = self.object_pose
                self.des_pose.pose.position.x = self.object_pose.x
                self.des_pose.pose.position.y = self.object_pose.y
                self.vel_control.publish(self.des_pose)
                rospy.loginfo("Centering...")
                while not self.target_reached:
                    rospy.sleep(2)

            elif self.detected and abs(self.object_pose.x) < 0.05 and abs(self.object_pose.y) < 0.05:
                self.des_pose.pose.position.x = 0
                self.des_pose.pose.position.y = 0
                self.des_pose.pose.position.z = self.local_pose.pose.position.z - 0.1
                rospy.loginfo("Descending...")
                self.vel_control.publish(self.des_pose)
                while not self.target_reached:
                    rospy.sleep(2)

        print("Landing")
        self.vel_control.publish(self.des_pose)
        self.rate.sleep()
        self.result.position_reached.data = True
        self.action_server.set_succeeded(self.result)

    def get_cam_pos_callback(self, data):
        if data.x != float("inf"):
            self.detected = True
            self.object_pose = data
        else:
            self.detected = False

    def _local_pose_callback(self, data):
        self.local_pose = data

    def distance_reached_cb(self, data):
        self.target_reached = data.data

if __name__ == '__main__':
    try:

        rospy.init_node('descend_on_object_server')
        descend_on_object_server()
    except rospy.ROSInterruptException:
        pass