public abstract class PaginableInventory extends InventoryConstructor {
    @Setter private List<Icon> iconsPage;
    @Getter private int size;
    @Setter @Getter private int page;
    @Setter private Player player;

    //ICONS NEXT and BEFORE
    @Setter private Icon nextPage;
    @Setter private int positionNextPage;
    @Setter private Icon previousPage;
    @Setter private int positionPreviousPage;

    public PaginableInventory(int sizeGui) {
        super(sizeGui);
        this.size = sizeGui;
    }

    private void emptyInventory() {
        if(getInventory().firstEmpty() == -1) {
            for(int i = 0; i < size + 1; i++) {
                getInventory().remove(i);
            }
            player.updateInventory();
        }
    }

    public void setPage(int page) {
        Objects.requireNonNull(positionNextPage, "Position Next Page is missing");
        Objects.requireNonNull(positionPreviousPage, "Position Previous Page is missing");

        int maxPage = getMaxPage();
        Bukkit.broadcastMessage("MaxPage: " + String.valueOf(iconsPage.size() / size));

        if(page > maxPage) {
            if(this.page == maxPage) return;
            page = maxPage;
        } else if( page < 0) {
            if(page == 0) return;
            page = 0;
        }

        if(maxPage > 0) {
            if(page == maxPage && previousPage != null) {
                setItem(previousPage, positionPreviousPage);
            } else if(page == maxPage && nextPage != null) {
                setItem(nextPage, positionNextPage);
            } else {
                //PREVIOUS
                ItemStack head_previous = AlixMaterial.PLAYER_HEAD.parseItem();
                ItemMeta meta_previous = head_previous.getItemMeta();
                AlixSkull.applySkin(meta_previous, "eyJ0ZXh0dXJlcyI6eyJTS0lOIjp7InVybCI6Imh0dHA6Ly90ZXh0dXJlcy5taW5lY3JhZnQubmV0L3RleHR1cmUvNWYxMzNlOTE5MTlkYjBhY2VmZGMyNzJkNjdmZDg3YjRiZTg4ZGM0NGE5NTg5NTg4MjQ0NzRlMjFlMDZkNTNlNiJ9fX0=");
                head_previous.setItemMeta(meta_previous);

                //NEXT
                ItemStack head_next = AlixMaterial.PLAYER_HEAD.parseItem();
                ItemMeta meta_next = head_next.getItemMeta();
                AlixSkull.applySkin(meta_next, "eyJ0ZXh0dXJlcyI6eyJTS0lOIjp7InVybCI6Imh0dHA6Ly90ZXh0dXJlcy5taW5lY3JhZnQubmV0L3RleHR1cmUvZTNmYzUyMjY0ZDhhZDllNjU0ZjQxNWJlZjAxYTIzOTQ3ZWRiY2NjY2Y2NDkzNzMyODliZWE0ZDE0OTU0MWY3MCJ9fX0=");
                head_previous.setItemMeta(meta_next);

                if(previousPage == null) previousPage = new Icon(head_previous, action -> { previousPage(); });
                if(nextPage == null) nextPage = new Icon(head_next, action -> { nextPage(); });
                setItem(nextPage, positionNextPage);
                setItem(previousPage, positionPreviousPage);
            }
        }

        this.page = page;

        emptyInventory();

        //Add Items
        List<Icon> icons = getPageItems(page);
        for(int i = 0; i < iconsPage.size(); i++) {
            if(i < icons.size()) {
                if(getInventory().getItem(i) == null) {
                    addItem(icons.get(i));
                    continue;
                }
                setItem(icons.get(i), i);
            }
        }
    }

    public int getMaxPage() {
        //Math.round(iconsPage.size() / size)
        return (int) Math.ceil(iconsPage.size() / size);
    }

    public void nextPage() {
        this.setPage(page + 1);
    }
    public void previousPage() {
        this.setPage(page - 1);
    }

    public InventoryConstructor getInventoryConstructor() { return this; }

    public List<Icon> getPageItems(int i) {
        int Start = i * size;
        int End = Math.min((i + 1) * size, iconsPage.size());

        return iconsPage.subList(Start, End);
    }
}