function sort_by_amount(x, y)
  return x.amount > y.amount
end

function get_items()
    local available_items = a.getAvailableItems()
    local item_list = {}
    local n = 1

    print(#available_items)

    for key,value in pairs( available_items ) do
        local z = available_items[key]
        local id = z[1]
        item_list[n] = {}
        item_list[n].id = id
        item_list[n].name = id --string.sub(getUnlocalizedName(item_list[key].id),1,20)
        item_list[n].amount = a.getItemAmount(item_list[key].id)
        if (key%10 == 0) then
            sleep(0.05)
        end
        n= n+1
    end
    table.sort(item_list, sort_by_amount)
    return item_list
end

function display_items(item_list)
    monX = 1
    monY = 2
    mon.clear()
    for i = 1, total_items_to_display,1 do
        name = item_list[i].name
        amount = item_list[i].amount
        mon.setCursorPos(monY, monX)
        mon.write(name)
        mon.setCursorPos(monY+21,monX)
        mon.write(":        ")
        amount_string = tostring(amount).." |"
        mon.setCursorPos(monY+30-string.len(amount_string),monX)
        mon.write(amount_string)
        if monX == items_to_display_per_row then
            monX = 0
            monY = monY+30
        end
        monX = monX+1
    end
end

function main()
    while true do
        item_list = get_items()
        display_items(item_list)
        sleep(10)
    end
end

function boot()
    iteration = 1
    a = peripheral.wrap(a_direction)
    mon = peripheral.wrap(mon_direction)
    mon.setTextScale(0.5)
    mon.clear()
    mon.setTextScale(0.5)
    mon.setCursorPos(34,26)
    mon.write("AE  display  system  booting  up,  stand by...")
    mon.setCursorPos(36,32)

end

items_to_display_per_row = 52
total_items_to_display = 208

a_direction = "back"
mon_direction = "top"

boot()
main()