chess/src/dev/kske/chess/uci/UCIReceiver.java

package dev.kske.chess.uci;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.StringJoiner;

import dev.kske.chess.uci.UCIListener.GUIType;

/**
 * Project: <strong>Chess</strong><br>
 * File: <strong>UCIReceiver.java</strong><br>
 * Created: <strong>19.07.2019</strong><br>
 * Author: <strong>Kai S. K. Engelbart</strong>
 */
public class UCIReceiver implements Runnable {

	private final BufferedReader in;

	private UCIListener listener;

	public UCIReceiver(InputStream in) {
		this.in = new BufferedReader(new InputStreamReader(in));
	}

	@Override
	public void run() {
		String line;
		while (!Thread.currentThread().isInterrupted())
			try {
				if ((line = in.readLine()) != null && !line.isBlank()) parse(line);
			} catch (IndexOutOfBoundsException ex) {
				System.err.println("Too few arguments were provided!");
				ex.printStackTrace();
			} catch (IOException ex) {
				ex.printStackTrace();
			}
	}

	private void parse(String line) {
		int		spaceIndex	= line.indexOf(' ');
		String	command		= spaceIndex == -1 ? line : line.substring(0, spaceIndex);
		switch (command) {
			case "id":
				parseId(line.substring(command.length() + 1));
				break;
			case "uciok":
				listener.onUCIOk();
				break;
			case "readyok":
				listener.onReadyOk();
				break;
			// TODO: bestmove
			case "copyprotection":
				parseCopyProtection(line.substring(command.length() + 1));
				break;
			case "registration":
				parseRegistration(line.substring(command.length() + 1));
				break;
			case "info":
				parseInfo(line.substring(command.length() + 1));
				break;
			case "option":
				parseOption(line.substring(command.length() + 1));
				break;
			default:
				System.err.printf("Unknown command '%s' found!%n", command);
		}
	}

	private void parseId(String line) {
		String	param	= line.substring(0, line.indexOf(' '));
		String	arg		= line.substring(param.length() + 1);
		switch (param) {
			case "name":
				listener.onIdName(arg);
				break;
			case "author":
				listener.onIdAuthor(arg);
				break;
			default:
				System.err.printf("Unknown parameter '%s' for command 'id' found!%n", param);
		}
	}

	private void parseCopyProtection(String line) {
		switch (line) {
			case "checking":
				listener.onCopyProtectionChecking();
				break;
			case "ok":
				listener.onCopyProtectionOk();
				break;
			case "error":
				listener.onCopyProtectionError();
				break;
			default:
				System.err.printf("Unknown parameter '%s' for command 'copyprotection' found!%n", line);
		}
	}

	private void parseRegistration(String line) {
		switch (line) {
			case "checking":
				listener.onRegistrationChecking();
				break;
			case "ok":
				listener.onRegistrationOk();
				break;
			case "error":
				listener.onRegistrationError();
				break;
			default:
				System.err.printf("Unknown parameter '%s' for command 'registration' found!%n", line);
		}
	}

	private void parseInfo(String line) {
		String[]			tokens			= line.split(" ");
		Map<String, String>	additionalInfo	= new HashMap<>();

		for (int i = 0; i < tokens.length; i++)
			switch (tokens[i]) {
				// Single parameter info
				case "depth":
				case "seldepth":
				case "time":
				case "nodes":
				case "multipv":
				case "currmove":
				case "currmovenumber":
				case "hashfull":
				case "nps":
				case "tbhits":
				case "sbhits":
				case "cpuload":
				case "string":
					additionalInfo.put(tokens[i], tokens[++i]);
					break;
				// TODO: pv
				// TODO: score
				// TODO: refutation
				// TODO: currline
				default:
					System.err.printf("Unknown parameter '%s' for command 'info' found!%n", tokens[i]);
			}
		listener.onInfo(additionalInfo);
	}

	private void parseOption(String line) {
		String[] tokens = line.split(" ");

		StringJoiner	name		= new StringJoiner(" ");
		GUIType			type		= null;
		String			defaultVal	= null;
		String			minVal		= null;
		String			maxVal		= null;
		List<String>	var			= new ArrayList<>();

		for (int i = 0; i < tokens.length; i++)
			switch (tokens[i]) {
				case "name":
					while (!Arrays.asList("type", "default", "min", "max", "var").contains(tokens[i + 1]))
						name.add(tokens[++i]);
					break;
				case "type":
					type = GUIType.valueOf(tokens[++i].toUpperCase());
					break;
				case "default":
					// Default string may be empty
					defaultVal = i == tokens.length - 1 ? "" : tokens[++i];
					break;
				case "min":
					minVal = tokens[++i];
					break;
				case "max":
					maxVal = tokens[++i];
					break;
				case "var":
					var.add(tokens[++i]);
					break;
				default:
					System.err.printf("Unknown parameter '%s' for command 'option' found!%n", tokens[i]);
			}
		listener.onOption(name.toString(), type, defaultVal, minVal, maxVal, var);
	}

	public void setListener(UCIListener listener) { this.listener = listener; }
}