app.py

import gradio as gr
from client import CobotController
from utils import get_credentials
import json
import threading
import time
from collections import deque
import namesgenerator

# Queue system setup
SESSION_TIME = 120

class QueueSystem:
	def __init__(self):
		self.queue = deque()
		self.current_user = None
		self.session_start_time = None
		self.lock = threading.Lock()

	def enqueue_user(self, user_id):
		with self.lock:
			if user_id not in self.queue and user_id != self.current_user:
				self.queue.append(user_id)

	def dequeue_user(self):
		with self.lock:
			if self.queue:
				return self.queue.popleft()
			return None

	def get_queue_info(self, user_id):
		with self.lock:
			if user_id == self.current_user:
				remaining_time = max(0, SESSION_TIME - (time.time() - self.session_start_time))
				return 0, remaining_time
			elif user_id in self.queue:
				position = list(self.queue).index(user_id) + 1
				if self.session_start_time:
					wait_time = (position - 1) * SESSION_TIME + max(0, SESSION_TIME - (time.time() - self.session_start_time))
				else:
					wait_time = position * SESSION_TIME
				return position, wait_time
			else:
				return None, None

	def start_session(self, user_id):
		with self.lock:
			if self.current_user is None:
				self.current_user = user_id
				self.session_start_time = time.time()
				return True
			return False

	def end_session(self):
		with self.lock:
			if self.current_user and time.time() - self.session_start_time >= SESSION_TIME:
				self.current_user = None
				self.session_start_time = None
				return True
			return False

queue_system = QueueSystem()

def queue_size():
	return f"There are {len(queue_system.queue)} people in the queue."

# Background timer thread to end session after SESSION_TIME
def background_timer():
	while True:
		time.sleep(1)
		if queue_system.end_session():
			next_user = queue_system.dequeue_user()
			if next_user:
				queue_system.start_session(next_user)

timer_thread = threading.Thread(target=background_timer, daemon=True)
timer_thread.start()

user, pwd, host, endpoint, port = get_credentials(False)
client = CobotController(user, pwd, host, port, endpoint)

CSS = """
#col {
	background-color: #161624;
	padding: 16px;
	border-radius: 8px;
}
#nogaprow {
	gap: 0px !important; 
}
#nogapcol {
	padding: 0px !important;
	border: none !important;
	box-shadow: none !important;
}
"""

def handle_request(
	command, gripper_value, gripper_speed, angle1, angle2, angle3, angle4,
	angle5, angle6, angle_speed, xcoord, ycoord, zcoord, roll, pitch, yaw, coord_speed,image_box
):
	if command == "enterqueue":
		return "", gr.Image(visible=False)
	elif command == "query/angles":
		resp = client.get_angles()
		resp["command"] = command
		return json.dumps(resp, indent=4), image_box
	elif command == "query/coords":
		resp = client.get_coords()
		resp["command"] = command
		return json.dumps(resp, indent=4), image_box
	elif command == "query/camera":
		resp = client.get_camera()
		resp["command"] = command
		if not resp["success"]:
			return json.dumps(resp, indent=4)
		img = resp.pop("image")
		return json.dumps(resp, indent=4), gr.Image(visible=True, value=img)
	elif command == "query/gripper":
		resp = client.get_gripper_value()
		resp["command"] = command
		return json.dumps(resp, indent=4), image_box
	elif command == "control/angles":
		resp = client.send_angles(
			angle_list = [angle1, angle2, angle3, angle4, angle5, angle6],
			speed = angle_speed
		)
		resp["command"] = command

		image_resp = client.get_camera()
		image_ret = gr.Image(value=image_resp["image"], visible=True) if image_resp["success"] else gr.Image(visible=False)
		return json.dumps(resp, indent=4), image_ret
	elif command == "control/gripper":
		resp = client.send_gripper_value(
			value = gripper_value,
			speed = gripper_speed
		)
		resp["command"] = command

		image_resp = client.get_camera()
		image_ret = gr.Image(value=image_resp["image"], visible=True) if image_resp["success"] else gr.Image(visible=False)
		return json.dumps(resp, indent=4), image_ret
	elif command == "control/coords":
		resp = client.send_coords(
			coord_list = [xcoord, ycoord, zcoord, roll, pitch, yaw],
			speed = coord_speed
		)
		resp["command"] = command

		image_resp = client.get_camera()
		image_ret = gr.Image(value=image_resp["image"], visible=True) if image_resp["success"] else gr.Image(visible=False)
		return json.dumps(resp, indent=4), image_ret

def process_user_auth(command, user_id, gripper_value, gripper_speed, angle1, angle2, angle3, angle4,
					  angle5, angle6, angle_speed, xcoord, ycoord, zcoord, roll, pitch, yaw, coord_speed, output_image):
	if queue_system.current_user is None:
		queue_system.start_session(user_id)
	queue_system.enqueue_user(user_id)
	position, wait_time = queue_system.get_queue_info(user_id)
	
	if position == 0:
		result, response_image = handle_request(
			command, gripper_value, gripper_speed, angle1, angle2, angle3, angle4,
			angle5, angle6, angle_speed, xcoord, ycoord, zcoord, roll, pitch, yaw, coord_speed, output_image
		)
		remaining_time_msg = f"Your turn!\nTime remaining: {wait_time:.2f} seconds."
		return result, response_image, remaining_time_msg
	elif position is not None:
		if position == 1:
			wait_msg = f"You are next!\nWait time: {wait_time:.2f} seconds."
		else:
			wait_msg = f"There are {position - 1} people ahead of you in the queue.\nWait time: {wait_time:.2f} seconds."
		return None, None, wait_msg
	else:
		return None, None, "Error: You are not in the queue."


with gr.Blocks(css=CSS) as app:
	gr.Markdown("# MyCobot 280pi MQTT Control Demo")
	gr.Markdown("This is a demo that uses the MQTT protocol to communicate with the MyCobot 280pi over the internet. You can remotely send commands to the cobot and query it's current status.")

	with gr.Row():
		with gr.Column():
			user_id = gr.Textbox(label="User ID", info="Enter a unique user id of your choice or take note of the automatically generated user id. This user id will be placed into a queue to give you access to the cobot, so make sure you remember it!")
			enter_queue_button = gr.Button("Join queue")
		with gr.Column():
			status_text = gr.Textbox(label="Queue status", value="", interactive=False, lines=5)

	with gr.Row():
		# QUERY PANEL
		with gr.Column(elem_id="col"):
			gr.Markdown("## Query")
			gr.Markdown("Use buttons on this panel to query the current status of the cobot, including information like joint angles, coordinates, gripper state and what the onboard camera sees.")
			angle_query_button = gr.Button("Query Angles")
			coord_query_button = gr.Button("Query Coordinates")
			gripper_query_button = gr.Button("Query Gripper state")
			camera_query_button = gr.Button("Query Camera")

		# GRIPPER PANEL
		with gr.Column(elem_id="col"):
			gr.Markdown("## Gripper Control")
			gr.Markdown("Use this panel to control the gripper of the cobot.")
			gripper_value = gr.Slider(minimum=0.0, maximum=100.0, step=1.0, label="Gripper value")
			speed_gripper = gr.Slider(value=50.0, minimum=0.0, maximum=100.0, step=1.0, label="Movement speed")
			gripper_control_button = gr.Button("Send gripper command")

	with gr.Row():
		# ANGLE PANEL
		with gr.Column(elem_id="col"):
			gr.Markdown("## Angle Control")
			gr.Markdown("Use this panel to control the joint angles of the cobot. Each angle corresponds to one of the 6 joints on the cobot.")
			with gr.Row(elem_id="nogaprow"):
				with gr.Column(elem_id="nogapcol"):
					angle1 = gr.Slider(value=0.0, label="Angle 1", step=1.0, minimum=-168, maximum=168)
					angle3 = gr.Slider(value=0.0, label="Angle 3", step=1.0, minimum=-135, maximum=135)
					angle5 = gr.Slider(value=0.0, label="Angle 5", step=1.0, minimum=-150, maximum=150)
				with gr.Column(elem_id="nogapcol"):
					angle2 = gr.Slider(value=0.0, label="Angle 2", step=1.0, minimum=-145, maximum=145)
					angle4 = gr.Slider(value=0.0, label="Angle 4", step=1.0, minimum=-165, maximum=165)
					angle6 = gr.Slider(value=0.0, label="Angle 6", step=1.0, minimum=-180, maximum=180)
			speed_angles = gr.Slider(value=50.0, minimum=0.0, maximum=100.0, step=1.0, label="Movement speed")
			angle_control_button = gr.Button("Send angle command")

		# COORD PANEL
		with gr.Column(elem_id="col"):
			gr.Markdown("## Coordinate Control")
			gr.Markdown("Use this panel to control the joint coordinates of the cobot head. The angles are in [6-DoF format](https://en.wikipedia.org/wiki/Six_degrees_of_freedom).")
			with gr.Row(elem_id="nogaprow"):
				with gr.Column(elem_id="nogapcol"):
					xcoord = gr.Slider(value=0.0, label="X coordinate", step=1.0, minimum=-350, maximum=350)
					ycoord = gr.Slider(value=0.0, label="Y coordinate", step=1.0, minimum=-350, maximum=350)
					zcoord = gr.Slider(value=0.0, label="Z coordinate", step=1.0, minimum=-70, maximum=523)
				with gr.Column(elem_id="nogapcol"):
					roll = gr.Slider(value=0.0, label="Roll", step=1.0, minimum=-180, maximum=180)
					pitch = gr.Slider(value=0.0, label="Pitch", step=1.0, minimum=-180, maximum=180)
					yaw = gr.Slider(value=0.0, label="Yaw", step=1.0, minimum=-180, maximum=180)
			speed_coords = gr.Slider(value=50.0, minimum=0.0, maximum=100.0, step=1.0, label="Movement speed")
			coord_control_button = gr.Button("Send coordinate command")
	
	response = gr.Textbox(label="Response")
	response_image = gr.Image(visible=False)

	# Queue-aware event handling
	angle_query_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="query/angles", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	coord_query_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="query/coords", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	gripper_query_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="query/gripper", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	camera_query_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="query/camera", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	gripper_control_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="control/gripper", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	angle_control_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="control/angles", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	coord_control_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="control/coords", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)
	enter_queue_button.click(
		process_user_auth,
		inputs = [gr.Textbox(value="enterqueue", visible=False), user_id, gripper_value, speed_gripper, angle1, angle2, angle3, angle4,
				  angle5, angle6, speed_angles, xcoord, ycoord, zcoord, roll, pitch, yaw, speed_coords, response_image],
		outputs = [response, response_image, status_text]
	)

	app.load(
		namesgenerator.get_random_name,
		outputs=[user_id]
	)

	app.load(
		queue_size,
		outputs=[status_text]
	)

app.queue(default_concurrency_limit=1, max_size=100)
app.launch()