package com.redstoner.modules.cycle;

import java.io.File;
import java.util.UUID;

import org.bukkit.GameMode;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.PlayerItemHeldEvent;
import org.bukkit.inventory.Inventory;
import org.bukkit.inventory.ItemStack;
import org.json.simple.JSONArray;

import com.nemez.cmdmgr.Command;
import com.redstoner.annotations.AutoRegisterListener;
import com.redstoner.annotations.Commands;
import com.redstoner.annotations.Version;
import com.redstoner.misc.CommandHolderType;
import com.redstoner.misc.JsonManager;
import com.redstoner.misc.Main;
import com.redstoner.modules.Module;

@Commands(CommandHolderType.File)
@AutoRegisterListener
@Version(major = 5, minor = 0, revision = 0, compatible = 4)
public class Cycle implements Module, Listener {
	private File cycleFile = new File(Main.plugin.getDataFolder(), "cycle.json");
	private JSONArray no_cyclers;

	@Override
	public boolean onEnable() {
		no_cyclers = JsonManager.getArray(cycleFile);
		if (no_cyclers == null) no_cyclers = new JSONArray();

		return true;
	}

	@Override
	public void onDisable() {
		saveCyclers();
	}

	private void saveCyclers() {
		JsonManager.save(no_cyclers, cycleFile);
	}

	@Command(hook = "cycle_on")
	public boolean cycleOn(CommandSender sender) {
		UUID uid = ((Player) sender).getUniqueId();

		if (no_cyclers.remove(uid.toString())) {
			getLogger().message(sender, "Cycle enabled!");
			saveCyclers();
		} else getLogger().message(sender, "Cycle was already enabled!");

		return true;
	}

	@SuppressWarnings("unchecked")
	@Command(hook = "cycle_off")
	public boolean cycleOff(CommandSender sender) {
		UUID uid = ((Player) sender).getUniqueId();

		if (!no_cyclers.contains(uid.toString())) {
			getLogger().message(sender, "Cycle disabled!");
			no_cyclers.add(uid.toString());
			saveCyclers();
		} else getLogger().message(sender, "Cycle was already disabled!");

		return true;
	}

	@EventHandler
	public void onInventoryCycle(PlayerItemHeldEvent event) {
		Player player = event.getPlayer();
		UUID uid = player.getUniqueId();

		if (!player.getGameMode().equals(GameMode.CREATIVE) || player.isSneaking() || no_cyclers.contains(uid.toString())) return;

		int prev_slot = event.getPreviousSlot();
		int new_slot = event.getNewSlot();

		if (prev_slot == 0 && new_slot == 8) shift(player, false);
		else if (prev_slot == 8 && new_slot == 0) shift(player, true);
	}

	private void shift(Player player, boolean down) {
		Inventory inv = player.getInventory();
		ItemStack[] items = inv.getStorageContents();

		int shift = down ? -9 : 9;
		shift = (shift + items.length) % items.length;

		for (int i = 0; i < 4; i++) {
			items = join(subset(items, shift, items.length), subset(items, 0, shift));

			ItemStack[] hotbar = subset(items, 0, 9);
			boolean found = false;

			for (ItemStack item : hotbar) if (item != null) {
				found = true;
				break;
			}

			if (found) break;
		}

		inv.setStorageContents(items);
	}

	private ItemStack[] subset(ItemStack[] items, int start, int end) {
		ItemStack[] result = new ItemStack[end - start];

		for (int i = start; i < end; i++) {
			result[i - start] = items[i];
		}

		return result;
	}

	private ItemStack[] join(ItemStack[] items1, ItemStack[] items2) {
		ItemStack[] result = new ItemStack[items1.length + items2.length];

		for (int i = 0; i < items1.length; i++) result[i] = items1[i];
		int offset = items1.length;
		for (int i = 0; i < items2.length; i++) result[i + offset] = items2[i];

		return result;
	}
}