local function sandport(pos)
    for i = -1,1,2 do
        for j = -1,1,2 do
            if ( minetest.get_node({x=pos.x+i, y=pos.y+2, z=pos.z+j}).name ~= "default:torch"
                 and minetest.get_node({x=pos.x+i, y=pos.y+2, z=pos.z+j}).name ~= "torches:floor" )
            or minetest.get_node({x=pos.x+i, y=pos.y+2, z=pos.z+j}).param2 ~= 1
            or minetest.get_node({x=pos.x+i, y=pos.y+1, z=pos.z+j}).name ~= "default:sand"
            or minetest.get_node({x=pos.x+i, y=pos.y, z=pos.z+j}).name ~= "default:sand" then
                return false
            end
        end
        if minetest.get_node({x=pos.x+i, y=pos.y-2, z=pos.z+i*2}).name ~= "default:mese"
        or minetest.get_node({x=pos.x+i*2, y=pos.y-2, z=pos.z+i}).name ~= "default:mese"
        or (not minetest.registered_nodes[minetest.get_node({x=pos.x+i*2, y=pos.y-1, z=pos.z}).name].walkable)
        or (not minetest.registered_nodes[minetest.get_node({x=pos.x, y=pos.y-1, z=pos.z+i*2}).name].walkable)
        or minetest.get_node({x=pos.x+i, y=pos.y, z=pos.z}).name ~= "default:sand"
        or minetest.get_node({x=pos.x, y=pos.y, z=pos.z+i}).name ~= "default:sand"
        or minetest.get_node({x=pos.x+i*2, y=pos.y, z=pos.z}).name ~= "default:water_source"
        or minetest.get_node({x=pos.x, y=pos.y, z=pos.z+i*2}).name ~= "default:water_source" then
            return false
        end
    end
    for k = 3,4,1 do
        for i = -k,k,2*k do
            for j = -k,k,2*k do
                if ( minetest.get_node({x=pos.x+i, y=pos.y, z=pos.z+j}).name ~= "default:torch"
                     and minetest.get_node({x=pos.x+i, y=pos.y, z=pos.z+j}).name ~= "torches:floor")
                or minetest.get_node({x=pos.x+i, y=pos.y, z=pos.z+j}).param2 ~= 1 then
                    return false
                end
            end
        end
        if minetest.get_node({x=pos.x, y=pos.y+k-3, z=pos.z}).name ~= "default:mese" then
            return false
        end
    end
    return true
end

local function use_sand_portal(pos)
    minetest.sound_play("nyanland_portal", {pos = pos,  gain = 0.5, max_hear_distance = 5})
    minetest.add_particlespawner{
        amount = 300,
        time = 17,
        minpos = {x=pos.x-0.2, y=pos.y+0.5, z=pos.z-0.2},
        maxpos = {x=pos.x+0.2, y=pos.y+0.4, z=pos.z+0.2},
        minvel = {x=-0.2, y=-0, z=-0.2},
        maxvel = {x=0.2, y=0, z=0.2},
        minacc = {x=-0.5,y=4,z=-0.5},
        maxacc = {x=0.5,y=5,z=0.5},
        minexptime = 1,
        maxexptime = 10,
        minsize = 1,
        maxsize = 9,
        collisiondetection = true,
        texture = "smoke_puff.png"
    }
    minetest.after(math.random(16), function()
        local target_pos = {x=pos.x, y=pos.y + nyanland_height + 10, z=pos.z}
        local objs = minetest.get_objects_inside_radius({x=pos.x, y=pos.y+0.5, z=pos.z}, 1)
        for _, obj in pairs(objs) do
            obj:setpos(target_pos)
        end
        minetest.sound_play("nyanland_cat", {pos = target_pos,  gain = 0.9, max_hear_distance = 35})
    end)
end

minetest.register_on_punchnode(function(pos, node, puncher)
    if puncher:get_wielded_item():get_name() == "default:stick"
    and node.name == "default:mese" --actually not necesary
    and sandport{x=pos.x, y=pos.y-1, z=pos.z} then
        use_sand_portal(pos)
    end
end)