package net.minecraft.server.commands;

import com.mojang.brigadier.CommandDispatcher;
import com.mojang.brigadier.arguments.FloatArgumentType;
import com.mojang.brigadier.arguments.IntegerArgumentType;
import java.util.Arrays;
import java.util.Locale;
import net.minecraft.commands.CommandSourceStack;
import net.minecraft.commands.Commands;
import net.minecraft.commands.SharedSuggestionProvider;
import net.minecraft.commands.arguments.TimeArgument;
import net.minecraft.network.chat.Component;
import net.minecraft.server.ServerTickRateManager;
import net.minecraft.util.TimeUtil;

public class TickCommand {
	private static final float MAX_TICKRATE = 10000.0F;
	private static final String DEFAULT_TICKRATE = String.valueOf(20);

	public static void register(final CommandDispatcher<CommandSourceStack> dispatcher) {
		dispatcher.register(
			Commands.literal("tick")
				.requires(Commands.hasPermission(Commands.LEVEL_ADMINS))
				.then(Commands.literal("query").executes(c -> tickQuery(c.getSource())))
				.then(
					Commands.literal("rate")
						.then(
							Commands.argument("rate", FloatArgumentType.floatArg(1.0F, 10000.0F))
								.suggests((c, b) -> SharedSuggestionProvider.suggest(new String[]{DEFAULT_TICKRATE}, b))
								.executes(c -> setTickingRate(c.getSource(), FloatArgumentType.getFloat(c, "rate")))
						)
				)
				.then(
					Commands.literal("step")
						.executes(c -> step(c.getSource(), 1))
						.then(Commands.literal("stop").executes(c -> stopStepping(c.getSource())))
						.then(
							Commands.argument("time", TimeArgument.time(1))
								.suggests((c, b) -> SharedSuggestionProvider.suggest(new String[]{"1t", "1s"}, b))
								.executes(c -> step(c.getSource(), IntegerArgumentType.getInteger(c, "time")))
						)
				)
				.then(
					Commands.literal("sprint")
						.then(Commands.literal("stop").executes(c -> stopSprinting(c.getSource())))
						.then(
							Commands.argument("time", TimeArgument.time(1))
								.suggests((c, b) -> SharedSuggestionProvider.suggest(new String[]{"60s", "1d", "3d"}, b))
								.executes(c -> sprint(c.getSource(), IntegerArgumentType.getInteger(c, "time")))
						)
				)
				.then(Commands.literal("unfreeze").executes(c -> setFreeze(c.getSource(), false)))
				.then(Commands.literal("freeze").executes(c -> setFreeze(c.getSource(), true)))
		);
	}

	private static String nanosToMilisString(final long nanos) {
		return String.format(Locale.ROOT, "%.1f", (float)nanos / (float)TimeUtil.NANOSECONDS_PER_MILLISECOND);
	}

	private static int setTickingRate(final CommandSourceStack source, final float rate) {
		ServerTickRateManager manager = source.getServer().tickRateManager();
		manager.setTickRate(rate);
		String tickRateString = String.format(Locale.ROOT, "%.1f", rate);
		source.sendSuccess(() -> Component.translatable("commands.tick.rate.success", tickRateString), true);
		return (int)rate;
	}

	private static int tickQuery(final CommandSourceStack source) {
		ServerTickRateManager manager = source.getServer().tickRateManager();
		String busyTime = nanosToMilisString(source.getServer().getAverageTickTimeNanos());
		float tickRate = manager.tickrate();
		String tickRateString = String.format(Locale.ROOT, "%.1f", tickRate);
		if (manager.isSprinting()) {
			source.sendSuccess(() -> Component.translatable("commands.tick.status.sprinting"), false);
			source.sendSuccess(() -> Component.translatable("commands.tick.query.rate.sprinting", tickRateString, busyTime), false);
		} else {
			if (manager.isFrozen()) {
				source.sendSuccess(() -> Component.translatable("commands.tick.status.frozen"), false);
			} else if (manager.nanosecondsPerTick() < source.getServer().getAverageTickTimeNanos()) {
				source.sendSuccess(() -> Component.translatable("commands.tick.status.lagging"), false);
			} else {
				source.sendSuccess(() -> Component.translatable("commands.tick.status.running"), false);
			}

			String milliSecondsPerTickTarget = nanosToMilisString(manager.nanosecondsPerTick());
			source.sendSuccess(() -> Component.translatable("commands.tick.query.rate.running", tickRateString, busyTime, milliSecondsPerTickTarget), false);
		}

		long[] samples = Arrays.copyOf(source.getServer().getTickTimesNanos(), source.getServer().getTickTimesNanos().length);
		Arrays.sort(samples);
		String p50 = nanosToMilisString(samples[samples.length / 2]);
		String p95 = nanosToMilisString(samples[(int)(samples.length * 0.95)]);
		String p99 = nanosToMilisString(samples[(int)(samples.length * 0.99)]);
		source.sendSuccess(() -> Component.translatable("commands.tick.query.percentiles", p50, p95, p99, samples.length), false);
		return (int)tickRate;
	}

	private static int sprint(final CommandSourceStack source, final int time) {
		boolean interrupted = source.getServer().tickRateManager().requestGameToSprint(time);
		if (interrupted) {
			source.sendSuccess(() -> Component.translatable("commands.tick.sprint.stop.success"), true);
		}

		source.sendSuccess(() -> Component.translatable("commands.tick.status.sprinting"), true);
		return 1;
	}

	private static int setFreeze(final CommandSourceStack source, final boolean freeze) {
		ServerTickRateManager manager = source.getServer().tickRateManager();
		if (freeze) {
			if (manager.isSprinting()) {
				manager.stopSprinting();
			}

			if (manager.isSteppingForward()) {
				manager.stopStepping();
			}
		}

		manager.setFrozen(freeze);
		if (freeze) {
			source.sendSuccess(() -> Component.translatable("commands.tick.status.frozen"), true);
		} else {
			source.sendSuccess(() -> Component.translatable("commands.tick.status.running"), true);
		}

		return freeze ? 1 : 0;
	}

	private static int step(final CommandSourceStack source, final int advance) {
		ServerTickRateManager manager = source.getServer().tickRateManager();
		boolean success = manager.stepGameIfPaused(advance);
		if (success) {
			source.sendSuccess(() -> Component.translatable("commands.tick.step.success", advance), true);
		} else {
			source.sendFailure(Component.translatable("commands.tick.step.fail"));
		}

		return 1;
	}

	private static int stopStepping(final CommandSourceStack source) {
		ServerTickRateManager manager = source.getServer().tickRateManager();
		boolean success = manager.stopStepping();
		if (success) {
			source.sendSuccess(() -> Component.translatable("commands.tick.step.stop.success"), true);
			return 1;
		} else {
			source.sendFailure(Component.translatable("commands.tick.step.stop.fail"));
			return 0;
		}
	}

	private static int stopSprinting(final CommandSourceStack source) {
		ServerTickRateManager manager = source.getServer().tickRateManager();
		boolean success = manager.stopSprinting();
		if (success) {
			source.sendSuccess(() -> Component.translatable("commands.tick.sprint.stop.success"), true);
			return 1;
		} else {
			source.sendFailure(Component.translatable("commands.tick.sprint.stop.fail"));
			return 0;
		}
	}
}