package net.minecraft.server.dedicated;

import com.google.common.collect.Streams;
import com.mojang.logging.LogUtils;
import java.lang.management.ManagementFactory;
import java.lang.management.ThreadInfo;
import java.lang.management.ThreadMXBean;
import java.nio.file.Path;
import java.util.Locale;
import java.util.Timer;
import java.util.TimerTask;
import java.util.stream.Collectors;
import net.minecraft.CrashReport;
import net.minecraft.CrashReportCategory;
import net.minecraft.CrashReportDetail;
import net.minecraft.ReportType;
import net.minecraft.Util;
import net.minecraft.server.Bootstrap;
import net.minecraft.util.TimeUtil;
import net.minecraft.world.level.GameRules;
import org.slf4j.Logger;

public class ServerWatchdog implements Runnable {
	private static final Logger LOGGER = LogUtils.getLogger();
	private static final long MAX_SHUTDOWN_TIME = 10000L;
	private static final int SHUTDOWN_STATUS = 1;
	private final DedicatedServer server;
	private final long maxTickTimeNanos;

	public ServerWatchdog(DedicatedServer server) {
		this.server = server;
		this.maxTickTimeNanos = server.getMaxTickLength() * TimeUtil.NANOSECONDS_PER_MILLISECOND;
	}

	public void run() {
		while (this.server.isRunning()) {
			long l = this.server.getNextTickTime();
			long m = Util.getNanos();
			long n = m - l;
			if (n > this.maxTickTimeNanos) {
				LOGGER.error(
					LogUtils.FATAL_MARKER,
					"A single server tick took {} seconds (should be max {})",
					String.format(Locale.ROOT, "%.2f", (float)n / (float)TimeUtil.NANOSECONDS_PER_SECOND),
					String.format(Locale.ROOT, "%.2f", this.server.tickRateManager().millisecondsPerTick() / (float)TimeUtil.MILLISECONDS_PER_SECOND)
				);
				LOGGER.error(LogUtils.FATAL_MARKER, "Considering it to be crashed, server will forcibly shutdown.");
				CrashReport crashReport = createWatchdogCrashReport("Watching Server", this.server.getRunningThread().threadId());
				this.server.fillSystemReport(crashReport.getSystemReport());
				CrashReportCategory crashReportCategory = crashReport.addCategory("Performance stats");
				crashReportCategory.setDetail(
					"Random tick rate", (CrashReportDetail<String>)(() -> this.server.getWorldData().getGameRules().getRule(GameRules.RULE_RANDOMTICKING).toString())
				);
				crashReportCategory.setDetail(
					"Level stats",
					(CrashReportDetail<String>)(() -> (String)Streams.stream(this.server.getAllLevels())
						.map(serverLevel -> serverLevel.dimension().location() + ": " + serverLevel.getWatchdogStats())
						.collect(Collectors.joining(",\n")))
				);
				Bootstrap.realStdoutPrintln("Crash report:\n" + crashReport.getFriendlyReport(ReportType.CRASH));
				Path path = this.server.getServerDirectory().resolve("crash-reports").resolve("crash-" + Util.getFilenameFormattedDateTime() + "-server.txt");
				if (crashReport.saveToFile(path, ReportType.CRASH)) {
					LOGGER.error("This crash report has been saved to: {}", path.toAbsolutePath());
				} else {
					LOGGER.error("We were unable to save this crash report to disk.");
				}

				this.exit();
			}

			try {
				Thread.sleep((l + this.maxTickTimeNanos - m) / TimeUtil.NANOSECONDS_PER_MILLISECOND);
			} catch (InterruptedException var10) {
			}
		}
	}

	public static CrashReport createWatchdogCrashReport(String title, long threadId) {
		ThreadMXBean threadMXBean = ManagementFactory.getThreadMXBean();
		ThreadInfo[] threadInfos = threadMXBean.dumpAllThreads(true, true);
		StringBuilder stringBuilder = new StringBuilder();
		Error error = new Error("Watchdog");

		for (ThreadInfo threadInfo : threadInfos) {
			if (threadInfo.getThreadId() == threadId) {
				error.setStackTrace(threadInfo.getStackTrace());
			}

			stringBuilder.append(threadInfo);
			stringBuilder.append("\n");
		}

		CrashReport crashReport = new CrashReport(title, error);
		CrashReportCategory crashReportCategory = crashReport.addCategory("Thread Dump");
		crashReportCategory.setDetail("Threads", stringBuilder);
		return crashReport;
	}

	private void exit() {
		try {
			Timer timer = new Timer();
			timer.schedule(new TimerTask() {
				public void run() {
					Runtime.getRuntime().halt(1);
				}
			}, 10000L);
			System.exit(1);
		} catch (Throwable var2) {
			Runtime.getRuntime().halt(1);
		}
	}
}