minecraft-kajetans-mod/src/main/java/me/km/skills/SkillContainer.java

package me.km.skills;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import me.km.inventory.CustomContainer;
import me.km.inventory.EntityInventory;
import net.minecraft.entity.player.EntityPlayerMP;
import net.minecraft.init.Items;
import net.minecraft.inventory.ClickType;
import net.minecraft.inventory.IInventory;
import net.minecraft.item.ItemStack;

public class SkillContainer extends CustomContainer
{
    private final List<Map.Entry<Skill, Byte>> skills;
    private final ArrayList<List<ItemStack>> pages;
    private int page;
    
    public SkillContainer(String title, EntityPlayerMP p, List<ItemStack> stacks, List<Map.Entry<Skill, Byte>> list) 
    {
        super(title, stacks.size() % 9 != 0 ? ((stacks.size() / 9) + 1) + 9 : stacks.size(), p);
        
        //System.out.println("ANZAHL DER SKILLS: " + stacks.size());
        
        EntityInventory inv = (EntityInventory) super.getShownInventory();
        if(inv.getSizeInventory() > 45)
        {
            inv.setContents(stacks.subList(0, 45));
            placeButtons(inv);
        }
        else
        {
            inv.setContents(stacks);
        }
        
        this.skills = list;
        this.page = 0;
        if(stacks.size() > 45)
        {
            this.pages = new ArrayList<>();
            int size = stacks.size();
            int counter = 0;
            while(counter < size)
            {
                pages.add(stacks.subList(counter, Math.min(counter + 45, size)));
                counter += 45;
            }
        }
        else
        {
            this.pages = null;
        }
    }
    
    private List<ItemStack> getNextPage()
    {
        page++;
        if(page >= pages.size())
        {
            page--;
            return null;
        }
        return pages.get(page);
    }
    
    private List<ItemStack> getPreviousPage()
    {
        page--;
        if(page < 0)
        {
            page = 0;
            return null;
        }
        return pages.get(page);
    }
    
    private Map.Entry<Skill, Byte> getSkill(int slot)
    {
        slot += page * 45;
        if(skills == null || slot >= skills.size())
        {
            return null;
        }
        return skills.get(slot);
    }
    
    private void placeButtons(IInventory inv)
    {
        inv.setInventorySlotContents(45, new ItemStack(Items.IRON_DOOR).setStackDisplayName("§6Zurück"));
        inv.setInventorySlotContents(53, new ItemStack(Items.OAK_DOOR).setStackDisplayName("§Vorwärts"));
    }

    public boolean castClickedSkill()
    {
        return false;
    }
    
    public void onCastSkill(EntityPlayerMP p, Skill s, byte level)
    {
        
    }
    
    @Override
    public void onCanceledClick(int slot, int dragType, ClickType clickTypeIn, EntityPlayerMP p) 
    {
        if(slot >= 45)
        {
            if(slot == 45)
            {
                List<ItemStack> list = getPreviousPage();
                if(list == null)
                {
                    return;
                }
                EntityInventory inv = (EntityInventory) getShownInventory();
                inv.setContents(list);
                placeButtons(inv);
            }
            else if(slot == 53)
            {
                List<ItemStack> list = getNextPage();
                if(list == null)
                {
                    return;
                }
                EntityInventory inv = (EntityInventory) getShownInventory();
                inv.setContents(list);
                placeButtons(inv);
            }
            return;
        }
        if(castClickedSkill())
        {
            Map.Entry<Skill, Byte> entry = getSkill(slot);
            if(entry == null)
            {
                return;
            }
            Skill s = entry.getKey();
            if(s == null)
            {
                return;
            }
            onCastSkill(p, s, entry.getValue());
        }
    }
}