--Circle Mode Lua Script Draft

local button_number = 1 -- the button number we want to read, as defined in AP_Button
local button_active_state = true --the 'pressed' state of the button
local last_button_state
local RUN_INTERVAL_MS  = 100
local ROVER_MODE_GUIDED =  15
local ROVER_MODE_LOITER =  5

local circle_angle = 0
local circle_angle_increment = 1 -- increment the target angle by 1 degree every 0.1 sec (10deg/sec)
local circle_speed = 1
local last_mode = vehicle:get_mode()


function update() -- the loop which periodically runs
	local button_new_state = button:get_button_state(button_number) == button_active_state 

-- the button has changed since the last loop

if button_new_state ~=last_button_state then
	last_button_state = button_new_state
	
	if button_new_state then
		gcs:send_text(0, "LUA: Button pressed")

		function do_circle()
		circle_angle = 0
		vehicle:set_mode (ROVER_MODE_GUIDED)
	end

	return do_circle, RUN_INTERVAL_MS
end

-- calculate velocity vector

circle_angle = circle_angle + circle_angle_increment
if (circle_angle >=360) then
	vehicle:set_mode(last_mode)
	return do_circle, RUN_INTERVAL_MS
end
local target_vel = Vector3f()
target_vel:x(math.sin(math.rad(circle_angle)) * circle_speed)
target_vel:y(math.cos(math.rad(circle_angle)) * circle_speed)
target_vel:z(0)

-- send velocity request
if not (vehicle:set_target_velocty_NED(target_vel)) then
	gcs:send_text(0, "failed to execute velocity command")
end
return do_circle, RUN_INTERVAL_MS
end

return do_circle()


	else
		gcs:send_text(0, "LUA: Button released")
	end