package com.keuin.ohmyvanillamc;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonIOException;
import com.mojang.brigadier.Command;
import com.mojang.brigadier.CommandDispatcher;
import com.mojang.brigadier.context.CommandContext;
import com.mojang.brigadier.exceptions.CommandSyntaxException;
import net.fabricmc.api.ModInitializer;
import net.fabricmc.fabric.api.command.v1.CommandRegistrationCallback;
import net.minecraft.server.command.CommandManager;
import net.minecraft.server.command.ServerCommandSource;
import net.minecraft.text.LiteralText;

import java.io.*;
import java.nio.charset.StandardCharsets;
import java.util.logging.Logger;

public class OhMyVanillaMinecraft implements ModInitializer {

	private static final Logger LOGGER = Logger.getLogger("OhMyVanillaMinecraft");

	private static OmvmConfiguration configuration = null;
	private static final OmvmConfiguration defaultConfiguration = new OmvmConfiguration();

	public static OmvmConfiguration getConfiguration() {
		return configuration != null ? configuration : defaultConfiguration;
	}

	@Override
	public void onInitialize() {
		// This code runs as soon as Minecraft is in a mod-load-ready state.
		// However, some things (like resources) may still be uninitialized.
		// Proceed with mild caution.

		LOGGER.info("Loading configuration...");

		// load configuration

		final String fileName = "omvm.json";
		final File file = new File(fileName);
		if (!file.exists()) {
			LOGGER.info("Configuration file does not exist! Use default configuration.");
			try (FileOutputStream fileOutputStream = new FileOutputStream(file)) {
				final String jsonString = (new GsonBuilder().setPrettyPrinting().create()).toJson(defaultConfiguration);
				try (OutputStreamWriter outputStreamWriter = new OutputStreamWriter(fileOutputStream)) {
					outputStreamWriter.write(jsonString);
				}
			} catch (FileNotFoundException e) {
				LOGGER.severe("Cannot write default configuration to file `" + fileName + "`: " + e);
			} catch (IOException e) {
				LOGGER.severe("Failed to write default configuration to file `" + fileName + "`: " + e);
			}
		} else {
			try (FileInputStream fileInputStream = new FileInputStream(file)) {
				try (InputStreamReader inputStreamReader = new InputStreamReader(fileInputStream, StandardCharsets.UTF_8)) {
					try (BufferedReader reader = new BufferedReader(inputStreamReader)) {
						configuration = (new Gson()).fromJson(reader, OmvmConfiguration.class);
					}
				}
			} catch (IOException e) {
				LOGGER.severe("Failed to read config file `" + fileName + "`: " + e);
			} catch (JsonIOException e) {
				LOGGER.severe("Failed to decode config json file `" + fileName + "`: " + e);
			}
		}

		if (configuration == null) {
			configuration = defaultConfiguration;
		}

		LOGGER.info("Configuration: \n==========\n" + configuration + "\n==========");

		CommandRegistrationCallback.EVENT.register(new CommandRegistrationCallback() {
			@Override
			public void register(CommandDispatcher<ServerCommandSource> commandDispatcher, boolean b) {
				commandDispatcher.register(CommandManager.literal("omvm").executes(new Command<ServerCommandSource>() {
					@Override
					public int run(CommandContext<ServerCommandSource> context) throws CommandSyntaxException {
						String text = "OhMyVanillaMinecraft\n==========\n" + getConfiguration() + "\n==========";
						context.getSource().sendFeedback(new LiteralText(text), false);
						return 1; // 1: success, -1: fail
					}
				}));
			}
		});

	}
}