package ps.eden.server.net.event;

import java.nio.ByteBuffer;

import ps.eden.server.cache.Cache;
import ps.eden.server.cache.crypto.ISAACCipher;
import ps.eden.server.cache.misc.buffer.ByteBufferUtils;
import ps.eden.server.engine.GameEngine;
import ps.eden.server.engine.login.LoginEvent;
import ps.eden.server.engine.login.LoginResponse;
import ps.eden.server.game.node.entity.player.info.ClientInfo;
import ps.eden.server.game.node.entity.player.info.UIDInfo;
import ps.eden.server.game.system.registry.AccountRegister;
import ps.eden.server.net.Constants;
import ps.eden.server.net.IoEventHandler;
import ps.eden.server.net.IoSession;
import ps.eden.server.tools.StringUtils;

/**
 * Handles login event codec.
 * @author Emperor
 *
 */
public final class LoginEventHandler implements IoEventHandler {

	/**
	 * The default login opcode.
	 */
	private static final int DEFAULT_LOGIN = 16;

	/**
	 * The reconnect login opcode.
	 */
	private static final int RECONNECT_LOGIN = 18;

	@Override
	public void read(IoSession session, ByteBuffer buffer) {
		int opcode = buffer.get() & 0xFF;
		int length = buffer.getShort() & 0xFFFF;
		//System.out.println(opcode + ", " + length);
		if (length != buffer.remaining()) {
			session.write(LoginResponse.BAD_SESSION_ID);
			return;
		}
		if (buffer.getInt() != Constants.REVISION) {
			session.write(LoginResponse.UPDATED);
			return;
		}

		/*if (buffer.getLong() != 3847247243492844L) {
			session.write(LoginResponse.UPDATED);
			return;
		}*/

		String ip = session.getAddress();
		int connections = AccountRegister.ipToConnections.getOrDefault(ip, 0);
		if (connections >= 10) {
			session.write(LoginResponse.LOGIN_LIMIT_EXCEEDED);
			return;
		}
		AccountRegister.ipToConnections.put(ip, connections + 1);

		switch (opcode) {
		case DEFAULT_LOGIN:
			decodeLogin(session, buffer, false);
			break;
		case RECONNECT_LOGIN:
			decodeLogin(session, buffer, true);
			break;
		default:
			System.out.println("Invalid login opcode " + opcode + "!");
			session.write(LoginResponse.BAD_SESSION_ID);
		}
	}

	/**
	 * Decodes the login request.
	 * @param session The session.
	 * @param buffer The buffer containing the request data.
	 * @param reconnect If this is a reconnect login request.
	 */
	private void decodeLogin(IoSession session, ByteBuffer buffer, boolean reconnect) {
		//System.out.println("Decode login attempt (reconnect=" + reconnect + ") " + session.getAddress());
		buffer.get(); // Memory?
		buffer.get();// no advertisement = 1
		buffer.get();// 1
		int windowMode = buffer.get();// Screen size mode
		int screenWidth = buffer.getShort(); // Screen size Width
		int screenHeight = buffer.getShort(); // Screen size Height
		int displayMode = buffer.get(); // Display mode
		byte[] data = new byte[24]; // random.dat data.
		buffer.get(data);
		String something = ByteBufferUtils.getString(buffer);
		int affiliate = buffer.getInt();// Affiliate id
		buffer.getInt(); // Hash containing a bunch of settings
		short interfacePacketCounter = buffer.getShort();//Current interface packet counter.
		//System.out.println(Cache.getIndexes().length + " total indexes");
		for (int i = 0; i < 29/*Cache.getIndexes().length*/; i++) {
			int crc = Cache.getIndexes()[i] == null ? 0
					: Cache.getIndexes()[i].getInformation().getInformationContainer().getCrc();
			if (crc != buffer.getInt() && crc != 0) {
				session.write(LoginResponse.UPDATED);
				return;
				//continue;
			}
		}
		buffer = ByteBufferUtils.getRSABlock(buffer);
		int[] seed = ByteBufferUtils.getISAACSeed(buffer);
		session.setCipherIn(new ISAACCipher(seed));
		for (int i = 0; i < seed.length; i++) {
			seed[i] += 50;
		}
		session.setCipherOut(new ISAACCipher(seed));
		String username = StringUtils.longToString(buffer.getLong());
		String lowered = username.toLowerCase();
		if (lowered.contains("kratos") || lowered.contains("krat0s") || lowered.contains("kr4t0s")) {
			System.err.println(session.getAddress() + " is a Kratos skiddy");
			session.write(LoginResponse.BAD_SESSION_ID);
			return;
		}
		if (affiliate != 38472812) {
			System.err.println(session.getAddress() + " is a Kratos skiddy");
			session.write(LoginResponse.UPDATED);
			return;
		}
		String password = ByteBufferUtils.getString(buffer);
		byte b = buffer.get();
		if (b != 4) {
			System.err.println(session.getAddress() + " is using an old client :)");
			session.write(LoginResponse.BAD_SESSION_ID);
			return;
		}
/*		if (!"stopsnoopingkid".equals(something)) {
			session.write(LoginResponse.UPDATED);
			return;
		}*/
		if (interfacePacketCounter != 23300) {
			System.err.println(session.getAddress() + " is a Kratos skiddy");
			session.write(LoginResponse.UPDATED);
			return;
		}
		UIDInfo info = new UIDInfo(session.getAddress(), ByteBufferUtils.getString(buffer),
				ByteBufferUtils.getString(buffer), ByteBufferUtils.getString(buffer));
		LoginEvent event = new LoginEvent(session, username, password, info);
		event.setReconnect(reconnect);
		event.setDisplayInfo(new ClientInfo(displayMode, windowMode, screenWidth, screenHeight));
		GameEngine.getLoginSchedule().schedule(event);
	}

	@Override
	public void write(IoSession session, Object... args) {
		if (args[0] instanceof LoginResponse) {
			LoginResponse response = (LoginResponse) args[0];
			ByteBuffer buffer = ByteBuffer.allocate(1);
			int opcode = response.opcode();
			buffer.put((byte) opcode);
			if (opcode == LoginResponse.MOVING_WORLD.opcode()) {
				buffer = ByteBuffer.allocate(2);
				buffer.put((byte) opcode);
				buffer.put((byte) 20);
			}
			session.write(buffer);
		} else {
			System.err.println("LoginEventHandler: " + args[0] + ", "
					+ (session == null ? "null" : session.getRemoteAddress()));
		}
	}

}