package dev.plutorocks;

import com.google.gson.Gson;
import com.google.gson.JsonSyntaxException;
import com.mojang.brigadier.context.CommandContext;
import com.mojang.brigadier.arguments.StringArgumentType;

import net.fabricmc.api.ClientModInitializer;
import net.fabricmc.fabric.api.client.command.v2.ClientCommandRegistrationCallback;
import net.fabricmc.fabric.api.client.command.v2.FabricClientCommandSource;
import net.fabricmc.fabric.api.client.message.v1.ClientSendMessageEvents;
import net.fabricmc.loader.api.FabricLoader;

import net.minecraft.client.MinecraftClient;
import net.minecraft.text.MutableText;
import net.minecraft.text.Text;
import net.minecraft.util.Formatting;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.io.Reader;
import java.io.Writer;
import java.nio.file.Files;
import java.nio.file.Path;

import static net.fabricmc.fabric.api.client.command.v2.ClientCommandManager.argument;
import static net.fabricmc.fabric.api.client.command.v2.ClientCommandManager.literal;

public class MinecraftIRC implements ClientModInitializer {
	public static final String MOD_ID = "minecraftirc";

	public static final Logger LOGGER = LoggerFactory.getLogger(MOD_ID);

	private static final Gson GSON = new Gson();
	private static final Path CONFIG_PATH = FabricLoader.getInstance().getConfigDir().resolve("minecraftirc.json");

	public static String ircHost = "irc.libera.chat";
	public static final int ircPort = 6667;
	public static String ircChannel = "#chat";
	public static String ircNick = "Player";

	public static IrcClient IRC_CLIENT;

	@Override
	public void onInitializeClient() {
		loadConfig();

		IRC_CLIENT = new IrcClient(ircHost, ircPort, ircChannel, ircNick);
		IRC_CLIENT.connect();

		ClientSendMessageEvents.CHAT.register(message -> {
			if (message.startsWith("!")) {
				if (IRC_CLIENT != null && IRC_CLIENT.isConnected()) {
					IRC_CLIENT.sendChannelMessage(message.substring(1));
				} else {
					sendIrcMessage("Not connected.");
				}
			}
		});

		ClientCommandRegistrationCallback.EVENT.register((dispatcher, registryAccess) -> {
			dispatcher.register(
					literal("irc")
							.then(literal("connect").executes(this::handleConnect))
							.then(literal("disconnect").executes(this::handleDisconnect))
							.then(literal("status").executes(this::handleStatus))
							.then(literal("host")
									.then(argument("host", StringArgumentType.word())
											.executes(this::handleSetHost)))
							.then(literal("channel")
									.then(argument("channel", StringArgumentType.word())
											.executes(this::handleSetChannel)))
							.then(literal("nick")
									.then(argument("nick", StringArgumentType.word())
											.executes(this::handleSetNick)))
			);
		});

		LOGGER.info("MinecraftIRC loaded!");
	}

	private static void loadConfig() {
		if (!Files.exists(CONFIG_PATH)) {
			applyDefaultsFromSession();
			saveConfig();
			return;
		}

		try (Reader reader = Files.newBufferedReader(CONFIG_PATH)) {
			Config cfg = GSON.fromJson(reader, Config.class);
			if (cfg == null) {
				applyDefaultsFromSession();
				saveConfig();
				return;
			}

			if (cfg.host != null && !cfg.host.isEmpty()) {
				ircHost = cfg.host;
			} else {
				ircHost = "irc.libera.chat";
			}

			if (cfg.channel != null && !cfg.channel.isEmpty()) {
				ircChannel = normalizeChannel(cfg.channel);
			} else {
				ircChannel = normalizeChannel("chat");
			}

			if (cfg.nick != null && !cfg.nick.isEmpty()) {
				ircNick = cfg.nick;
			} else {
				ircNick = defaultNickFromSession();
			}
		} catch (IOException | JsonSyntaxException e) {
			LOGGER.warn("Failed to read MinecraftIRC config, using defaults", e);
			applyDefaultsFromSession();
		}
	}

	private static void saveConfig() {
		Config cfg = new Config();
		cfg.host = ircHost;
		cfg.channel = ircChannel;
		cfg.nick = ircNick;

		try (Writer writer = Files.newBufferedWriter(CONFIG_PATH)) {
			GSON.toJson(cfg, writer);
		} catch (IOException e) {
			LOGGER.warn("Failed to save MinecraftIRC config", e);
		}
	}

	private static void applyDefaultsFromSession() {
		ircHost = "irc.libera.chat";
		ircChannel = normalizeChannel("chat");
		ircNick = defaultNickFromSession();
	}

	private static String defaultNickFromSession() {
		MinecraftClient client = MinecraftClient.getInstance();
		if (client != null && client.getSession() != null) {
			String name = client.getSession().getUsername();
			if (name != null && !name.isEmpty()) {
				return name;
			}
		}
		return "Player";
	}

	private int handleConnect(CommandContext<FabricClientCommandSource> ctx) {
		if (IRC_CLIENT != null && IRC_CLIENT.isConnected()) {
			IRC_CLIENT.disconnect();
		}

		IRC_CLIENT = new IrcClient(ircHost, ircPort, ircChannel, ircNick);

		sendCmdFeedback(ctx, "Connecting to " + ircHost + " " + ircChannel
				+ " as " + ircNick + " (port " + ircPort + ")...");
		IRC_CLIENT.connect();
		return 1;
	}

	private int handleDisconnect(CommandContext<FabricClientCommandSource> ctx) {
		if (IRC_CLIENT == null || !IRC_CLIENT.isConnected()) {
			sendCmdFeedback(ctx, "Already disconnected.");
			return 1;
		}

		IRC_CLIENT.disconnect();
		sendCmdFeedback(ctx, "Disconnected.");
		return 1;
	}

	private int handleStatus(CommandContext<FabricClientCommandSource> ctx) {
		String state = (IRC_CLIENT != null && IRC_CLIENT.isConnected()) ? "Connected" : "Not connected";
		sendCmdFeedback(ctx, state + ". Host=" + ircHost
				+ " Channel=" + ircChannel + " Nick=" + ircNick
				+ " Port=" + ircPort);
		return 1;
	}

	private int handleSetHost(CommandContext<FabricClientCommandSource> ctx) {
		ircHost = StringArgumentType.getString(ctx, "host");
		saveConfig();
		sendCmdFeedback(ctx, "Host set to " + ircHost + ". Use /irc connect to apply.");
		return 1;
	}

	private static String normalizeChannel(String raw) {
		raw = raw.trim();
		if (raw.isEmpty()) return "#chat";
		if (!raw.startsWith("#")) raw = "#" + raw;
		return raw;
	}

	private int handleSetChannel(CommandContext<FabricClientCommandSource> ctx) {
		String raw = StringArgumentType.getString(ctx, "channel");
		ircChannel = normalizeChannel(raw);
		saveConfig();
		sendCmdFeedback(ctx, "Channel set to " + ircChannel + ". Use /irc connect to apply.");
		return 1;
	}

	private int handleSetNick(CommandContext<FabricClientCommandSource> ctx) {
		ircNick = StringArgumentType.getString(ctx, "nick");
		saveConfig();
		sendCmdFeedback(ctx, "Nick set to " + ircNick + ". Use /irc connect to apply.");
		return 1;
	}

	private void sendCmdFeedback(CommandContext<FabricClientCommandSource> ctx, String grayMessage) {
		MutableText prefix = Text.literal("[IRC] ").formatted(Formatting.AQUA);
		MutableText body = Text.literal(grayMessage).formatted(Formatting.GRAY);
		ctx.getSource().sendFeedback(prefix.append(body));
	}

	private void sendIrcMessage(String grayMessage) {
		MinecraftClient client = MinecraftClient.getInstance();
		if (client == null) return;

		client.execute(() -> {
			if (client.inGameHud != null) {
				MutableText prefix = Text.literal("[IRC] ").formatted(Formatting.AQUA);
				MutableText body = Text.literal(grayMessage).formatted(Formatting.GRAY);
				client.inGameHud.getChatHud().addMessage(prefix.append(body));
			}
		});
	}

	private static class Config {
		String host;
		String channel;
		String nick;
	}
}