improve server side command line input (#415)

* improve server side command line input

* prevent multiline logs from covering typed commands

* reduce text in console

* resolve conflicts caused by multilanguage

Co-authored-by: Magix <kobedo11@gmail.com>

build.gradle

@@ -64,6 +64,10 @@ dependencies {
     implementation group: 'ch.qos.logback', name: 'logback-core', version: '1.2.9'
     implementation group: 'ch.qos.logback', name: 'logback-classic', version: '1.2.9'
 
+    implementation group: 'org.jline', name: 'jline', version: '3.21.0'
+    implementation group: 'org.jline', name: 'jline-terminal-jna', version: '3.21.0'
+    implementation group: 'net.java.dev.jna', name: 'jna', version: '5.10.0'
+
     implementation group: 'io.netty', name: 'netty-all', version: '4.1.71.Final'
 
     implementation group: 'com.google.code.gson', name: 'gson', version: '2.8.8'

src/main/java/emu/grasscutter/Grasscutter.java

 package emu.grasscutter;
 
-import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileReader;
 import java.io.FileWriter;
-import java.io.InputStreamReader;
+import java.io.IOError;
 import java.net.InetSocketAddress;
 import java.util.Calendar;
 
@@ -13,6 +12,12 @@ import emu.grasscutter.plugin.PluginManager;
 import emu.grasscutter.plugin.api.ServerHook;
 import emu.grasscutter.scripts.ScriptLoader;
 import emu.grasscutter.utils.Utils;
+import org.jline.reader.EndOfFileException;
+import org.jline.reader.LineReader;
+import org.jline.reader.LineReaderBuilder;
+import org.jline.reader.UserInterruptException;
+import org.jline.terminal.Terminal;
+import org.jline.terminal.TerminalBuilder;
 import org.reflections.Reflections;
 import org.slf4j.LoggerFactory;
 
@@ -30,6 +35,7 @@ import emu.grasscutter.utils.Crypto;
 public final class Grasscutter {
 	private static final Logger log = (Logger) LoggerFactory.getLogger(Grasscutter.class);
 	private static Config config;
+	private static LineReader consoleLineReader = null;
 	private static Language language;
 
 	private static final Gson gson = new GsonBuilder().setPrettyPrinting().create();
@@ -109,10 +115,11 @@ public final class Grasscutter {
 		// Enable all plugins.
 		pluginManager.enablePlugins();
 
-		// Open console.
-		startConsole();
 		// Hook into shutdown event.
 		Runtime.getRuntime().addShutdownHook(new Thread(Grasscutter::onShutdown));
+
+		// Open console.
+		startConsole();
     }
 
 	/**
@@ -167,24 +174,41 @@ public final class Grasscutter {
 	}
 	
 	public static void startConsole() {
-		String input;
-		getLogger().info(language.Start_done);
-		try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
-			while ((input = br.readLine()) != null) {
-				try {
+		// Console should not start in dispatch only mode.
 		if (getConfig().RunMode == ServerRunMode.DISPATCH_ONLY) {
-						getLogger().error(language.Dispatch_mode_not_support_command);
+			getLogger().info(language.Dispatch_mode_not_support_command);
 			return;
 		}
 
+		getLogger().info(language.Start_done);
+		String input = null;
+		boolean isLastInterrupted = false;
+		while (true) {
+			try {
+				input = consoleLineReader.readLine("> ");
+			} catch (UserInterruptException e) {
+				if (!isLastInterrupted) {
+					isLastInterrupted = true;
+					Grasscutter.getLogger().info("Press Ctrl-C again to shutdown.");
+					continue;
+				} else {
+					Runtime.getRuntime().exit(0);
+				}
+			} catch (EndOfFileException e) {
+				Grasscutter.getLogger().info("EOF detected.");
+				continue;
+			} catch (IOError e) {
+				Grasscutter.getLogger().error("An IO error occurred.", e);
+				continue;
+			}
+
+			isLastInterrupted = false;
+			try {
 				CommandMap.getInstance().invoke(null, input);
 			} catch (Exception e) {
 				Grasscutter.getLogger().error(language.Command_error, e);
 			}
 		}
-		} catch (Exception e) {
-			Grasscutter.getLogger().error(language.Error, e);
-		}
 	}
 
 	public static Config getConfig() {
@@ -199,6 +223,26 @@ public final class Grasscutter {
 		return log;
 	}
 
+	public static LineReader getConsole() {
+		if (consoleLineReader == null) {
+			Terminal terminal = null;
+			try {
+				terminal = TerminalBuilder.builder().jna(true).build();
+			} catch (Exception e) {
+				try {
+					// Fallback to a dumb jline terminal.
+					terminal = TerminalBuilder.builder().dumb(true).build();
+				} catch (Exception ignored) {
+					// When dumb is true, build() never throws.
+				}
+			}
+			consoleLineReader = LineReaderBuilder.builder()
+					.terminal(terminal)
+					.build();
+		}
+		return consoleLineReader;
+	}
+
 	public static Gson getGsonFactory() {
 		return gson;
 	}

src/main/java/emu/grasscutter/utils/JlineLogbackAppender.java

+package emu.grasscutter.utils;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.ConsoleAppender;
+import emu.grasscutter.Grasscutter;
+import org.jline.reader.LineReader;
+
+import java.util.Arrays;
+
+public class JlineLogbackAppender extends ConsoleAppender<ILoggingEvent> {
+    @Override
+    protected void append(ILoggingEvent eventObject) {
+        if (!started) {
+            return;
+        }
+        Arrays.stream(
+                new String(encoder.encode(eventObject)).split("\n")
+        ).forEach(Grasscutter.getConsole()::printAbove);
+    }
+}

src/main/resources/logback.xml

 <Configuration>
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+  <appender name="STDOUT" class="emu.grasscutter.utils.JlineLogbackAppender">
     <encoder>
       <pattern>[%d{HH:mm:ss}] [%highlight(%level)] %msg%n</pattern>
     </encoder>