/*
 * Minecraft Forge
 * Copyright (c) 2016.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation version 2.1
 * of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

package net.minecraftforge.server.console;

import static com.google.common.base.Preconditions.checkNotNull;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.bukkit.event.server.TabCompleteEvent;

import net.minecraft.server.dedicated.DedicatedServer;
import org.jline.reader.Candidate;
import org.jline.reader.Completer;
import org.jline.reader.LineReader;
import org.jline.reader.ParsedLine;

final class ConsoleCommandCompleter implements Completer {

	private static final Logger logger = LogManager.getLogger();
	private final DedicatedServer server;

	public ConsoleCommandCompleter(DedicatedServer server) {
		this.server = checkNotNull(server, "server");
	}

	@Override
	public void complete(LineReader reader, ParsedLine line, List<Candidate> candidates) {
		String buffer = line.line();
		boolean prefix;
		//forge getTabCompletions не принимает нулл.
		if (buffer.isEmpty() || buffer.charAt(0) != '/') {
			buffer = '/' + buffer;
			prefix = false;
		} else {
			prefix = true;
		}
		//Craftbukkit start
		//Для forge нужен слеш, иначе он не выводит полный список.
		final String forge = buffer;
		final String bakkit = line.line();
		Future<List<String>> tabComplete = this.server.callFromMainThread(() -> this.server.getTabCompletions(this.server, forge, this.server.getPosition(), false));
		Future<List<String>> offers = this.server.callFromMainThread(() -> server.server.getCommandMap().tabComplete(server.server.getConsoleSender(), bakkit));

		List<String> all = new ArrayList<String>();
		try {
			//Заполняем полный список forgeComplete, когда в buffer не было слеша.
			//Пропускаем список, когда в buffer был слеш.
			//Иначе список будет через слеш и смешается с complete worldedit.
			if (!prefix || buffer.isEmpty()) {
				for (String comp : tabComplete.get()) {
					boolean hasPrefix = comp.charAt(0) != '/';
					all.add(hasPrefix ? comp : comp.substring(1));
				}
			}
			//Заполняем список bukkitComplete, если вернуло не null.
			if (offers != null) {
				all.addAll(offers.get());
			}
		} catch (InterruptedException e) {
			Thread.currentThread().interrupt();
		} catch (ExecutionException e) {
			logger.error("Failed to tab complete", e);
		}

		//CallTabCompleteEvent
		TabCompleteEvent tabEvent = new TabCompleteEvent(server.server.getConsoleSender(), buffer, all);
		server.server.getPluginManager().callEvent(tabEvent);

		if (!tabEvent.isCancelled()) {
			for (String completion : tabEvent.getCompletions()) {
				if (!completion.isEmpty()) {
					Candidate candidate = new Candidate(completion);
					candidates.add(candidate);
				}
			}
		}
		//Craftbukkit end
	}
}