btu.place_at = function(item) 
	return bt.Sequence("", {
		bt.Approach(2),
		bt.Animate("punch"),
		bt.SetNode(item),
	})
end

btu.build_to = function(item) 
	return bt.Sequence("", {
		bt.Approach(2),
		bt.Animate("punch"),
		bt.SetNode(item),
	})
end


btu.wander_around = function() 
	return bt.Sequence("", {
		bt.RandomDirection(),
		bt.MoveInDirection(7),
		bt.Approach(2),
	})
end





-- designed for use in a selector
btu.forage_node = function(items, dist, counter, maxItems) 
	return bt.UntilFailed(bt.Sequence("forage "..dump(items), {
		bt.Invert(bt.Counter(counter, "gte", maxItems)),
		bt.FindNodeNear(items, dist),
		bt.Approach(2),
		bt.Animate("punch"),
		bt.DigNode(),
		bt.WaitTicks(1),
		bt.Counter(counter, "inc"),
	}))
end

btu.forage_item = function(items, dist, counter, maxItems) 
	return bt.UntilFailed(bt.Sequence("forage "..dump(items), {
		bt.Invert(bt.Counter(counter, "gte", maxItems)),
		bt.FindItemNear(item, dist),
		bt.Approach(2),
		bt.Animate("punch"),
		bt.PickUpNearbyItems(item, 2.5),
		bt.WaitTicks(1),
		bt.Counter(counter, "inc"),
	}))
end





btu.dig_region = function()
	return bt.Sequence("", {

-- 		bt.Invert(bt.UntilFailed(bt.Sequence("dig the hole", {
-- 			
-- -- 			bt.FindNodeInRange(),
-- -- 			bt.Approach(2),
-- 			
-- 			-- chop it down
			bt.Invert(bt.UntilFailed(bt.Sequence("dig hole", {
				bt.Print("before walk"),
				bt.WalkNonEmptyNodesInRange(),
				bt.Print("after walk"),
				
				bt.Approach(3),
				bt.Animate("punch"),
				bt.DigNode(),
				bt.WaitTicks(1),
			}))),
			
-- 			bt.Print("end of loop"),
-- 		})))
	})
end

btu.dig_hole = function(item) 
	return bt.Sequence("", {
		bt.Succeed(bt.FindGroupCampfire()),
		
		-- find a place for a hole
		bt.FindSpotOnGround(),
		bt.SetWaypoint("hole"),
		bt.FindRegionAround(4),
		
		btu.dig_region(item),
		
		bt.ScaleRegion({x=-1, y=0, z=-1}),
		bt.MoveRegion({x=0, y=-1, z=0}),
		btu.dig_region(item),

		bt.ScaleRegion({x=-1, y=0, z=-1}),
		bt.MoveRegion({x=0, y=-1, z=0}),
		btu.dig_region(item),
		
		bt.Die(),
	})
end


btu.fill_region = function(item)
	return bt.Sequence("", {

		bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
			
			bt.FindNodeInRange({"air"}),
			bt.Approach(2),
			
			bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
				bt.FindNodeInRange({"air"}),
				bt.Approach(3),
				bt.Animate("punch"),
				bt.SetNode(item),
				bt.WaitTicks(1),
			}))),
			
			bt.Print("end of loop"),
		})))
	})
end


btu.stack_on_ground = function(item, height)
	return bt.Sequence("", {
		bt.PushTarget(),
		
		bt.FindSurface(),
		bt.MoveTarget({x=0, y=1, z=0}),
		bt.Approach(2),
		
		bt.Counter("stacking", "set", height),
		
		bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
			bt.Animate("punch"),
			bt.SetNode(item),
			bt.WaitTicks(1),
			
			bt.MoveTarget({x=0, y=1, z=0}),
			bt.Counter("stacking", "dec"), 
			bt.Counter("stacking", "gt", 0), 
		}))),
		
		bt.PopTarget(),
	})
end

btu.dig_stack = function(height)
	return bt.Sequence("", {
		bt.PushTarget(),
		bt.Counter("stacking", "set", height),
		
		bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
			bt.Animate("punch"),
			bt.DigNode(),
-- 			bt.WaitTicks(1),
			
			bt.MoveTarget({x=0, y=-1, z=0}),
			bt.Counter("stacking", "dec"), 
			bt.Counter("stacking", "gt", 0), 
		}))),
		bt.PopTarget(),
	})
end

btu.set_stack = function(item, height)
	return bt.Sequence("", {
		bt.PushTarget(),
		bt.Counter("stacking", "set", height),
		
		bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
			bt.Animate("punch"),
			bt.SetNode(item),
-- 			bt.WaitTicks(1),
			
			bt.MoveTarget({x=0, y=-1, z=0}),
			bt.Counter("stacking", "dec"), 
			bt.Counter("stacking", "gt", 0), 
		}))),
		bt.PopTarget(),
	})
end

btu.fill_buildable_stack = function(item, height)
	return bt.Sequence("", {
		bt.PushTarget(),
		bt.Counter("stacking", "set", height),
		
		bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
			bt.Animate("punch"),
			
			bt.Succeed(bt.Sequence("", {
				bt.NodeBuildableTo("air"),
				bt.SetNode(item),
			})),
			
-- 			bt.WaitTicks(1),
			
			bt.MoveTarget({x=0, y=-1, z=0}),
			bt.Counter("stacking", "dec"), 
			bt.Counter("stacking", "gt", 0), 
		}))),
		bt.PopTarget(),
	})
end


btu.fence_region = function(item)
	return bt.Sequence("", {

		bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
			
			bt.FindPerimeterNodeInRegion({"air"}),
			bt.Approach(2),
			
			-- chop it down
			bt.Invert(bt.UntilFailed(bt.Sequence("fill region", {
				bt.FindPerimeterNodeInRegion({"air"}),
				bt.Approach(3),
				bt.Animate("punch"),
				bt.SetNode(item);
				bt.WaitTicks(1),
			}))),
			
			--bt.Print("end of loop"),
		})))
	})
end


btu.fill_item_rel_dir = function(check_item, fill_item, offset, dir)
	local dx = dir.x
	local dz = dir.z
	return bt.Sequence("", {
		bt.PushTarget(),
		
		bt.MoveTarget({
			x=offset.x*dx + offset.z*dz, 
			y=offset.y, 
			z=offset.z*dx + offset.x*dz
		}),
		
		bt.IsNode(check_item),
		bt.SetNode(fill_item),
		
		bt.PopTarget(),
	})
end