hopper/init.lua

local hopper_formspec =
	"size[8,9]"
	.. default.gui_bg
	.. default.gui_bg_img
	.. default.gui_slots
	.. "list[current_name;main;0,0.3;8,4;]"
	.. "list[current_player;main;0,4.85;8,1;]"
	.. "list[current_player;main;0,6.08;8,3;8]"
	.. "listring[current_name;main]"
	.. "listring[current_player;main]"

-- hopper
minetest.register_node("hopper:hopper", {
	description = "Hopper",
	groups = {cracky=1,level=2},
	drawtype = "nodebox",
	paramtype = "light",
	tiles = {"default_coal_block.png"},
	node_box = {
		type = "fixed",
		fixed = {
			--funnel walls
			{-0.5, 0.0, 0.4, 0.5, 0.5, 0.5},
			{0.4, 0.0, -0.5, 0.5, 0.5, 0.5},
			{-0.5, 0.0, -0.5, -0.4, 0.5, 0.5},
			{-0.5, 0.0, -0.5, 0.5, 0.5, -0.4},
			--funnel base
			{-0.5, 0.0, -0.5, 0.5, 0.1, 0.5},
			--spout
			{-0.3, -0.3, -0.3, 0.3, 0.0, 0.3},
			{-0.15, -0.3, -0.15, 0.15, -0.5, 0.15},
		},
	},

	on_construct = function(pos)
		local meta = minetest.get_meta(pos)
		meta:set_string("formspec", hopper_formspec)
		meta:set_string("infotext", "Hopper")
		local inv = meta:get_inventory()
		inv:set_size("main", 8*4)
	end,

	can_dig = function(pos,player)
		local meta = minetest.get_meta(pos)
		local inv = meta:get_inventory()
		return inv:is_empty("main")
	end,

	on_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player)
		minetest.log("action", player:get_player_name()..
				" moves stuff in hopper at "..minetest.pos_to_string(pos))
	end,

    on_metadata_inventory_put = function(pos, listname, index, stack, player)
		minetest.log("action", player:get_player_name()..
				" moves stuff to hopper at "..minetest.pos_to_string(pos))
	end,

    on_metadata_inventory_take = function(pos, listname, index, stack, player)
		minetest.log("action", player:get_player_name()..
				" takes stuff from hopper at "..minetest.pos_to_string(pos))
	end,
})

-- hopper side
minetest.register_node("hopper:hopper_side", {
	description = "Side Hopper",
	groups = {cracky=1,level=2},
	drawtype = "nodebox",
	paramtype = "light",
	paramtype2 = "facedir",
	tiles = {"default_coal_block.png"},
	node_box = {
		type = "fixed",
		fixed = {
			--funnel walls
			{-0.5, 0.0, 0.4, 0.5, 0.5, 0.5},
			{0.4, 0.0, -0.5, 0.5, 0.5, 0.5},
			{-0.5, 0.0, -0.5, -0.4, 0.5, 0.5},
			{-0.5, 0.0, -0.5, 0.5, 0.5, -0.4},
			--funnel base
			{-0.5, 0.0, -0.5, 0.5, 0.1, 0.5},
			--spout
			{-0.3, -0.3, -0.3, 0.3, 0.0, 0.3},
			{-0.7, -0.3, -0.15, 0.15, 0.0, 0.15},
		},
	},

	on_construct = function(pos)
		local meta = minetest.get_meta(pos)
		meta:set_string("formspec", hopper_formspec)
		meta:set_string("infotext", "Side Hopper")
		local inv = meta:get_inventory()
		inv:set_size("main", 8*4)
	end,

	can_dig = function(pos,player)
		local meta = minetest.get_meta(pos)
		local inv = meta:get_inventory()
		return inv:is_empty("main")
	end,

	on_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player)
		minetest.log("action", player:get_player_name()..
				" moves stuff in hopper at "..minetest.pos_to_string(pos))
	end,

    on_metadata_inventory_put = function(pos, listname, index, stack, player)
		minetest.log("action", player:get_player_name()..
				" moves stuff to hopper at "..minetest.pos_to_string(pos))
	end,

    on_metadata_inventory_take = function(pos, listname, index, stack, player)
		minetest.log("action", player:get_player_name()..
				" takes stuff from hopper at "..minetest.pos_to_string(pos))
	end,
})

-- suck in items on top of hopper
minetest.register_abm({
	nodenames = {"hopper:hopper","hopper:hopper_side"},
	interval = 1.0,
	chance = 1,
	action = function(pos, node, active_object_count, active_object_count_wider)
		local meta = minetest.get_meta(pos)
		local inv = meta:get_inventory()
		local posob

		for _,object in ipairs(minetest.get_objects_inside_radius(pos, 1)) do
			if not object:is_player() and object:get_luaentity() and object:get_luaentity().name == "__builtin:item" then
				if inv and inv:room_for_item("main", ItemStack(object:get_luaentity().itemstring)) then
					posob = object:getpos()
					if math.abs(posob.x-pos.x) <= 0.5 and (posob.y-pos.y <= 0.85 and posob.y-pos.y >= 0.3) then
						inv:add_item("main", ItemStack(object:get_luaentity().itemstring))
						object:get_luaentity().itemstring = ""
						object:remove()
					end
				end
			end
		end
	end,
})

-- transfer function
local transfer = function(src, srcpos, dst, dstpos)

	-- source inventory
	local meta = minetest.get_meta(srcpos)
	local inv = meta:get_inventory()
	local invsize = inv:get_size(src)

	-- check for empty source
	if inv:is_empty(src) == true then
		return
	end

	-- destination inventory
	local meta2 = minetest.get_meta(dstpos)
	local inv2 = meta2:get_inventory()
	local invsize2 = inv2:get_size(dst)

	local stack, item

	-- transfer item
	for i = 1,invsize do

		stack = inv:get_stack(src, i)
		item = stack:get_name()

		-- if slot not empty
		if item ~= "" then

			-- room in destination?
			if inv2:room_for_item(dst, item) == false then
				return
			end

			-- is item a tool
			if stack:get_wear() > 0 then -- tool
				local it = stack:take_item(stack:get_count())
				inv2:add_item(dst, it)
				inv:set_stack(src, i, nil)
			else -- everything else
				stack:take_item(1)
				inv2:add_item(dst, item)
				inv:set_stack(src, i, stack)
			end

			return

		end
	end

end

-- hopper transfer
minetest.register_abm({
	nodenames = {"hopper:hopper"},
	neighbors = {
		"default:chest","default:chest_locked","protector:chest",
		"hopper:hopper","hopper:hopper_side","default:furnace","default:furnace_active"
	},
	interval = 1.0,
	chance = 1,
	action = function(pos, node, active_object_count, active_object_count_wider)

		local min = {x=pos.x,y=pos.y-1,z=pos.z}
		local max = {x=pos.x,y=pos.y+1,z=pos.z}
		local vm = minetest.get_voxel_manip()	
		local emin, emax = vm:read_from_map(min,max)
		local area = VoxelArea:new{MinEdge=emin, MaxEdge=emax}
		local data = vm:get_data()	
		local a = vm:get_node_at({x=pos.x,y=pos.y+1,z=pos.z}).name
		local b = vm:get_node_at({x=pos.x,y=pos.y-1,z=pos.z}).name

		--local a = minetest.get_node({x=pos.x, y=pos.y+1, z=pos.z}).name
		--local b = minetest.get_node({x=pos.x, y=pos.y-1, z=pos.z}).name

		-- input (from above)

		if a == "default:chest"
		or a == "default:chest_locked"
		or a == "protector:chest"
		or a == "hopper:hopper"
		or a == "hopper:hopper_side" then

			-- chest/hopper above to hopper below
			transfer("main", {x=pos.x, y=pos.y+1, z=pos.z}, "main", pos)

		elseif a == "default:furnace" or a == "default:furnace_active" then

			-- furnace output above to hopper below
			transfer("dst", {x=pos.x, y=pos.y+1, z=pos.z}, "main", pos)

		end

		-- output (to below)

		if b == "default:chest"
		or b == "default:chest_locked"
		or b == "protector:chest" then

			-- hopper above to chest below
			transfer("main", pos, "main", {x=pos.x, y=pos.y-1, z=pos.z})
			
		elseif b == "default:furnace" or b == "default:furnace_active" then

			-- hopper above to furnace source below
			transfer("main", pos, "src", {x=pos.x, y=pos.y-1, z=pos.z})
		end
	
	end,
})

-- hopper side
minetest.register_abm({
	nodenames = {"hopper:hopper_side"},
	neighbors = {
		"default:chest","default:chest_locked","protector:chest",
		"hopper:hopper","hopper:hopper_side","default:furnace","default:furnace_active"
	},
	interval = 1.0,
	chance = 1,
	action = function(pos, node, active_object_count, active_object_count_wider)

		local min = {x=pos.x-1,y=pos.y,z=pos.z-1}
		local max = {x=pos.x+1,y=pos.y+1,z=pos.z+1}
		local vm = minetest.get_voxel_manip()	
		local emin, emax = vm:read_from_map(min,max)
		local area = VoxelArea:new{MinEdge=emin, MaxEdge=emax}
		local data = vm:get_data()	
		local face = vm:get_node_at(pos).param2

		local front = {}
		--local face = minetest.get_node(pos).param2
		--print(face)

		if face == 0 then
			front = {x=pos.x-1,y=pos.y,z=pos.z}
		elseif face == 1 then
			front = {x=pos.x,y=pos.y,z=pos.z+1}
		elseif face == 2 then
			front = {x=pos.x+1,y=pos.y,z=pos.z}
		elseif face == 3 then
			front = {x=pos.x,y=pos.y,z=pos.z-1}
		end

		local a = vm:get_node_at({x=pos.x,y=pos.y+1,z=pos.z}).name
		local b = vm:get_node_at(front).name

--		local a = minetest.get_node({x=pos.x, y=pos.y+1, z=pos.z}).name
--		local b = minetest.get_node(front).name

		-- input (from above)

		if a == "default:chest"
		or a == "default:chest_locked"
		or a == "protector:chest"
		or a == "hopper:hopper"
		or a == "hopper:hopper_side" then

			-- chest/hopper above to hopper below
			transfer("main", {x=pos.x, y=pos.y+1, z=pos.z}, "main", pos)

		elseif a == "default:furnace" or a == "default:furnace_active" then

			-- furnace output above to hopper below
			transfer("dst", {x=pos.x, y=pos.y+1, z=pos.z}, "main", pos)

		end

		-- output (to side)

		if b == "default:chest"
		or b == "default:chest_locked"
		or b == "protector:chest"
		or b == "hopper:hopper"
		or b == "hopper:hopper_side" then

			-- hopper to chest beside
			transfer("main", pos, "main", front)
			
		elseif b == "default:furnace" or b == "default:furnace_active" then

			-- hopper above to furnace fuel beside
			transfer("main", pos, "fuel", front)
		end
		
	end,
})

-- hopper recipe
minetest.register_craft({
	output = "hopper:hopper",
	recipe = {
		{"default:steel_ingot", "", "default:steel_ingot"},
		{"default:steel_ingot", "default:chest", "default:steel_ingot"},
		{"", "default:steel_ingot", ""},
	},
})

minetest.register_craft({
	output = "hopper:hopper",
	recipe = {
		{"hopper:hopper_side"},
	},
})

-- side hopper recipe
minetest.register_craft({
	output = "hopper:hopper_side",
	recipe = {
		{"hopper:hopper"},
	},
})