-- playername -> pos (if pos1 selected)
local pos1 = {}

minetest.register_tool("pick_and_place:configure", {
    description = "Placement configuration tool",
    inventory_image = "pick_and_place_plus.png^[colorize:#ffffff",
    stack_max = 1,
    range = 0,
    on_use = function(_, player)
        local playername = player:get_player_name()
        local pointed_pos = pick_and_place.get_pointed_position(player)

        if pos1[playername] then
            -- second position selected
            -- configure and unmark
            pick_and_place.configure(pos1[playername], pointed_pos)
            pos1[playername] = nil
        else
            -- first position selected
            pos1[playername] = pointed_pos
        end
    end,
    on_secondary_use = function(_, player)
        local playername = player:get_player_name()
        pos1[playername] = nil
    end,
    on_step = function(_, player)
        local playername = player:get_player_name()
        local pointed_pos = pick_and_place.get_pointed_position(player)

        if pos1[playername] then
            -- first position already selected
            pick_and_place.show_preview(playername, "pick_and_place_plus.png", "#ffffff", pointed_pos, pos1[playername])
        else
            -- nothing selected yet
            pick_and_place.show_preview(playername, "pick_and_place_plus.png", "#ffffff", pointed_pos)
        end
    end,
    on_deselect = function(_, player)
        local playername = player:get_player_name()
        pick_and_place.clear_preview(playername)
    end
})