diff --git a/maidroid_core/cores/farming.lua b/maidroid_core/cores/farming.lua
index 93e7eec..5f71a76 100644
--- a/maidroid_core/cores/farming.lua
+++ b/maidroid_core/cores/farming.lua
@@ -42,139 +42,170 @@ local function is_mowable_place(pos)
 	return false
 end
 
-do -- register farming core
 
-	local walk_randomly, walk_to_plant_and_mow_common, plant, mow
-	local to_walk_randomly, to_walk_to_plant, to_walk_to_mow, to_plant, to_mow
+local walk_randomly, walk_to_plant_and_mow_common, plant, mow
+local to_walk_randomly, to_walk_to_plant, to_walk_to_mow, to_plant, to_mow
 
-	local function on_start(self)
-		self.object:setacceleration{x = 0, y = -10, z = 0}
-		self.object:setvelocity{x = 0, y = 0, z = 0}
-		self.state = state.WALK_RANDOMLY
-		self.time_counters = {}
-		self.path = nil
-		to_walk_randomly(self)
-	end
+local function on_start(self)
+	self.object:setacceleration{x = 0, y = -10, z = 0}
+	self.object:setvelocity{x = 0, y = 0, z = 0}
+	self.state = state.WALK_RANDOMLY
+	self.time_counters = {}
+	self.path = nil
+	to_walk_randomly(self)
+end
 
-	local function on_stop(self)
-		self.object:setvelocity{x = 0, y = 0, z = 0}
-		self.state = nil
-		self.time_counters = nil
-		self.path = nil
-		self:set_animation(maidroid.animation_frames.STAND)
-	end
+local function on_stop(self)
+	self.object:setvelocity{x = 0, y = 0, z = 0}
+	self.state = nil
+	self.time_counters = nil
+	self.path = nil
+	self:set_animation(maidroid.animation_frames.STAND)
+end
 
-	local function is_near(self, pos, distance)
-		local p = self.object:getpos()
-		-- p.y = p.y + 0.5
-		return vector.distance(p, pos) < distance
-	end
+local function is_near(self, pos, distance)
+	local p = self.object:getpos()
+	-- p.y = p.y + 0.5
+	return vector.distance(p, pos) < distance
+end
 
-	local searching_range = {x = 5, y = 2, z = 5}
+local searching_range = {x = 5, y = 2, z = 5}
 
-	walk_randomly = function(self, dtime)
-		if self.time_counters[1] >= FIND_PATH_TIME_INTERVAL then
-			self.time_counters[1] = 0
-			self.time_counters[2] = self.time_counters[2] + 1
+walk_randomly = function(self, dtime)
+	if self.time_counters[1] >= FIND_PATH_TIME_INTERVAL then
+		self.time_counters[1] = 0
+		self.time_counters[2] = self.time_counters[2] + 1
 
-			local wield_stack = self:get_wield_item_stack()
-			if minetest.get_item_group(wield_stack:get_name(), "seed") > 0
-			or self:has_item_in_main(function(itemname)	return (minetest.get_item_group(itemname, "seed") > 0) end) then
-				local destination = _aux.search_surrounding(self.object:getpos(), is_plantable_place, searching_range)
-				if destination ~= nil then
-					local path = minetest.find_path(self.object:getpos(), destination, 10, 1, 1, "A*")
-
-					if path ~= nil then -- to walk to plant state.
-						to_walk_to_plant(self, path, destination)
-						return
-					end
-				end
-			end
-			-- if couldn't find path to plant, try to mow.
-			local destination = _aux.search_surrounding(self.object:getpos(), is_mowable_place, searching_range)
+		local wield_stack = self:get_wield_item_stack()
+		if minetest.get_item_group(wield_stack:get_name(), "seed") > 0
+		or self:has_item_in_main(function(itemname)	return (minetest.get_item_group(itemname, "seed") > 0) end) then
+			local destination = _aux.search_surrounding(self.object:getpos(), is_plantable_place, searching_range)
 			if destination ~= nil then
 				local path = minetest.find_path(self.object:getpos(), destination, 10, 1, 1, "A*")
-				if path ~= nil then -- to walk to mow state.
-					to_walk_to_mow(self, path, destination)
+
+				if path ~= nil then -- to walk to plant state.
+					to_walk_to_plant(self, path, destination)
 					return
 				end
 			end
-			-- else do nothing.
-			return
-
-		elseif self.time_counters[2] >= CHANGE_DIRECTION_TIME_INTERVAL then
-			self.time_counters[1] = self.time_counters[1] + 1
-			self.time_counters[2] = 0
-			self:change_direction_randomly()
-			return
-		else
-			self.time_counters[1] = self.time_counters[1] + 1
-			self.time_counters[2] = self.time_counters[2] + 1
-
-			local velocity = self.object:getvelocity()
-			if velocity.y == 0 then
-				local front_node = self:get_front_node()
-				if front_node.name ~= "air" and minetest.registered_nodes[front_node.name].walkable
-				and not (minetest.get_item_group(front_node.name, "fence") > 0) then
-					self.object:setvelocity{x = velocity.x, y = 6, z = velocity.z}
-				end
-			end
-			return
 		end
-	end
+		-- if couldn't find path to plant, try to mow.
+		local destination = _aux.search_surrounding(self.object:getpos(), is_mowable_place, searching_range)
+		if destination ~= nil then
+			local path = minetest.find_path(self.object:getpos(), destination, 10, 1, 1, "A*")
+			if path ~= nil then -- to walk to mow state.
+				to_walk_to_mow(self, path, destination)
+				return
+			end
+		end
+		-- else do nothing.
+		return
 
-	to_walk_randomly = function(self)
-		self.state = state.WALK_RANDOMLY
-		self.time_counters[1] = 0
+	elseif self.time_counters[2] >= CHANGE_DIRECTION_TIME_INTERVAL then
+		self.time_counters[1] = self.time_counters[1] + 1
 		self.time_counters[2] = 0
 		self:change_direction_randomly()
-		self:set_animation(maidroid.animation_frames.WALK)
-	end
+		return
+	else
+		self.time_counters[1] = self.time_counters[1] + 1
+		self.time_counters[2] = self.time_counters[2] + 1
 
-	to_walk_to_plant = function(self, path, destination)
-		self.state = state.WALK_TO_PLANT
-		self.path = path
-		self.destination = destination
-		self.time_counters[1] = 0 -- find path interval
-		self.time_counters[2] = 0
-		self:change_direction(self.path[1])
-		self:set_animation(maidroid.animation_frames.WALK)
-	end
-
-	to_walk_to_mow = function(self, path, destination)
-		self.state = state.WALK_TO_MOW
-		self.path = path
-		self.destination = destination
-		self.time_counters[1] = 0 -- find path interval
-		self.time_counters[2] = 0
-		self:change_direction(self.path[1])
-		self:set_animation(maidroid.animation_frames.WALK)
-	end
-
-	to_plant = function(self)
-		local wield_stack = self:get_wield_item_stack()
-		if minetest.get_item_group(wield_stack:get_name(), "seed") > 0
-		or self:move_main_to_wield(function(itemname)	return (minetest.get_item_group(itemname, "seed") > 0) end) then
-			self.state = state.PLANT
-			self.time_counters[1] = 0
-			self.object:setvelocity{x = 0, y = 0, z = 0}
-			self:set_animation(maidroid.animation_frames.MINE)
-			return
-		else
-			to_walk_randomly(self)
-			return
+		local velocity = self.object:getvelocity()
+		if velocity.y == 0 then
+			local front_node = self:get_front_node()
+			if front_node.name ~= "air" and minetest.registered_nodes[front_node.name].walkable
+			and not (minetest.get_item_group(front_node.name, "fence") > 0) then
+				self.object:setvelocity{x = velocity.x, y = 6, z = velocity.z}
+			end
 		end
+		return
 	end
+end
 
-	to_mow = function(self)
-		self.state = state.MOW
+to_walk_randomly = function(self)
+	self.state = state.WALK_RANDOMLY
+	self.time_counters[1] = 0
+	self.time_counters[2] = 0
+	self:change_direction_randomly()
+	self:set_animation(maidroid.animation_frames.WALK)
+end
+
+to_walk_to_plant = function(self, path, destination)
+	self.state = state.WALK_TO_PLANT
+	self.path = path
+	self.destination = destination
+	self.time_counters[1] = 0 -- find path interval
+	self.time_counters[2] = 0
+	self:change_direction(self.path[1])
+	self:set_animation(maidroid.animation_frames.WALK)
+end
+
+to_walk_to_mow = function(self, path, destination)
+	self.state = state.WALK_TO_MOW
+	self.path = path
+	self.destination = destination
+	self.time_counters[1] = 0 -- find path interval
+	self.time_counters[2] = 0
+	self:change_direction(self.path[1])
+	self:set_animation(maidroid.animation_frames.WALK)
+end
+
+to_plant = function(self)
+	local wield_stack = self:get_wield_item_stack()
+	if minetest.get_item_group(wield_stack:get_name(), "seed") > 0
+	or self:move_main_to_wield(function(itemname)	return (minetest.get_item_group(itemname, "seed") > 0) end) then
+		self.state = state.PLANT
 		self.time_counters[1] = 0
 		self.object:setvelocity{x = 0, y = 0, z = 0}
 		self:set_animation(maidroid.animation_frames.MINE)
+		return
+	else
+		to_walk_randomly(self)
+		return
+	end
+end
+
+to_mow = function(self)
+	self.state = state.MOW
+	self.time_counters[1] = 0
+	self.object:setvelocity{x = 0, y = 0, z = 0}
+	self:set_animation(maidroid.animation_frames.MINE)
+end
+
+walk_to_plant_and_mow_common = function(self, dtime)
+	if is_near(self, self.destination, 1.5) then
+		if self.state == state.WALK_TO_PLANT then
+			to_plant(self)
+			return
+		elseif self.state == state.WALK_TO_MOW then
+			to_mow(self)
+			return
+		end
 	end
 
-	walk_to_plant_and_mow_common = function(self, dtime)
-		if is_near(self, self.destination, 1.5) then
+	if self.time_counters[2] >= MAX_WALK_TIME then -- time over.
+		to_walk_randomly(self)
+		return
+	end
+
+	self.time_counters[1] = self.time_counters[1] + 1
+	self.time_counters[2] = self.time_counters[2] + 1
+
+	if self.time_counters[1] >= FIND_PATH_TIME_INTERVAL then
+		self.time_counters[1] = 0
+		local path = minetest.find_path(self.object:getpos(), self.destination, 10, 1, 1, "A*")
+		if path == nil then
+			to_walk_randomly(self)
+			return
+		end
+		self.path = path
+	end
+
+	-- follow path
+	if is_near(self, self.path[1], 0.5) then
+		table.remove(self.path, 1)
+
+		if #self.path == 0 then -- end of path
 			if self.state == state.WALK_TO_PLANT then
 				to_plant(self)
 				return
@@ -182,112 +213,78 @@ do -- register farming core
 				to_mow(self)
 				return
 			end
+		else -- else next step, follow next path.
+			self:change_direction(self.path[1])
 		end
 
-		if self.time_counters[2] >= MAX_WALK_TIME then -- time over.
-			to_walk_randomly(self)
-			return
+	else
+		-- self:change_direction(self.path[1])
+		-- if maidroid is stopped by obstacles, the maidroid must jump.
+		-- self:change_direction(self.path[1])
+		local velocity = self.object:getvelocity()
+		if velocity.y == 0 then
+			local front_node = self:get_front_node()
+			if front_node.name ~= "air" and minetest.registered_nodes[front_node.name].walkable
+			and not (minetest.get_item_group(front_node.name, "fence") > 0) then
+				self.object:setvelocity{x = velocity.x, y = 6, z = velocity.z}
+			end
 		end
+	end
+end
 
+plant = function(self, dtime)
+	if self.time_counters[1] >= 15 then
+		if is_plantable_place(self.destination) then
+			local stack = self:get_wield_item_stack()
+			local itemname = stack:get_name()
+			minetest.add_node(self.destination, {name = itemname, param2 = 1})
+			stack:take_item(1)
+			self:set_wield_item_stack(stack)
+		end
+		to_walk_randomly(self)
+		return
+	else
 		self.time_counters[1] = self.time_counters[1] + 1
-		self.time_counters[2] = self.time_counters[2] + 1
-
-		if self.time_counters[1] >= FIND_PATH_TIME_INTERVAL then
-			self.time_counters[1] = 0
-			local path = minetest.find_path(self.object:getpos(), self.destination, 10, 1, 1, "A*")
-			if path == nil then
-				to_walk_randomly(self)
-				return
-			end
-			self.path = path
-		end
-
-		-- follow path
-		if is_near(self, self.path[1], 0.5) then
-			table.remove(self.path, 1)
-
-			if #self.path == 0 then -- end of path
-				if self.state == state.WALK_TO_PLANT then
-					to_plant(self)
-					return
-				elseif self.state == state.WALK_TO_MOW then
-					to_mow(self)
-					return
-				end
-			else -- else next step, follow next path.
-				self:change_direction(self.path[1])
-			end
-
-		else
-			-- self:change_direction(self.path[1])
-			-- if maidroid is stopped by obstacles, the maidroid must jump.
-			-- self:change_direction(self.path[1])
-			local velocity = self.object:getvelocity()
-			if velocity.y == 0 then
-				local front_node = self:get_front_node()
-				if front_node.name ~= "air" and minetest.registered_nodes[front_node.name].walkable
-				and not (minetest.get_item_group(front_node.name, "fence") > 0) then
-					self.object:setvelocity{x = velocity.x, y = 6, z = velocity.z}
-				end
-			end
-		end
 	end
+end
 
-	plant = function(self, dtime)
-		if self.time_counters[1] >= 15 then
-			if is_plantable_place(self.destination) then
-				local stack = self:get_wield_item_stack()
-				local itemname = stack:get_name()
-				minetest.add_node(self.destination, {name = itemname, param2 = 1})
-				stack:take_item(1)
-				self:set_wield_item_stack(stack)
+mow = function(self, dtime)
+	if self.time_counters[1] >= 15 then
+		if is_mowable_place(self.destination) then
+			local destnode = minetest.get_node(self.destination)
+			minetest.remove_node(self.destination)
+			local stacks = minetest.get_node_drops(destnode.name)
+
+			for _, stack in ipairs(stacks) do
+				local leftover = self:add_item_to_main(stack)
+				minetest.add_item(self.destination, leftover)
 			end
-			to_walk_randomly(self)
-			return
-		else
-			self.time_counters[1] = self.time_counters[1] + 1
 		end
+		to_walk_randomly(self)
+		return
+	else
+		self.time_counters[1] = self.time_counters[1] + 1
 	end
+end
 
-	mow = function(self, dtime)
-		if self.time_counters[1] >= 15 then
-			if is_mowable_place(self.destination) then
-				local destnode = minetest.get_node(self.destination)
-				minetest.remove_node(self.destination)
-				local stacks = minetest.get_node_drops(destnode.name)
-
-				for _, stack in ipairs(stacks) do
-					local leftover = self:add_item_to_main(stack)
-					minetest.add_item(self.destination, leftover)
-				end
-			end
-			to_walk_randomly(self)
-			return
-		else
-			self.time_counters[1] = self.time_counters[1] + 1
-		end
+local function on_step(self, dtime)
+	if self.state == state.WALK_RANDOMLY then
+		walk_randomly(self, dtime)
+	elseif self.state == state.WALK_TO_PLANT or self.state == state.WALK_TO_MOW then
+		walk_to_plant_and_mow_common(self, dtime)
+	elseif self.state == state.PLANT then
+		plant(self, dtime)
+	elseif self.state == state.MOW then
+		mow(self, dtime)
 	end
+end
 
-	local function on_step(self, dtime)
-		if self.state == state.WALK_RANDOMLY then
-			walk_randomly(self, dtime)
-		elseif self.state == state.WALK_TO_PLANT or self.state == state.WALK_TO_MOW then
-			walk_to_plant_and_mow_common(self, dtime)
-		elseif self.state == state.PLANT then
-			plant(self, dtime)
-		elseif self.state == state.MOW then
-			mow(self, dtime)
-		end
-	end
-
-	maidroid.register_core("maidroid_core:farming", {
-		description      = "maidroid core : farming",
-		inventory_image  = "maidroid_core_farming.png",
-		on_start         = on_start,
-		on_stop          = on_stop,
-		on_resume        = on_start,
-		on_pause         = on_stop,
-		on_step          = on_step,
-	})
-
-end -- register farming core
+maidroid.register_core("maidroid_core:farming", {
+	description      = "maidroid core : farming",
+	inventory_image  = "maidroid_core_farming.png",
+	on_start         = on_start,
+	on_stop          = on_stop,
+	on_resume        = on_start,
+	on_pause         = on_stop,
+	on_step          = on_step,
+})