import {Client, Permissions} from "discord.js";
import $, {unreact} from "./core/lib";
import setup from "./setup";
import FileManager from "./core/storage";
import {Config, Storage} from "./core/structures";

(async() => {
	// Setup //
	await setup.init();
	const client = new Client();
	const commands = await FileManager.loadCommands();
	client.login(Config.token).catch(setup.again);
	
	client.on("message", async message => {
		// Message Setup //
		if(message.author.bot)
			return;
		
		const prefix = Storage.getGuild(message.guild?.id || "N/A").prefix || Config.prefix;
		
		if(!message.content.startsWith(prefix))
			return;
		
		const [header, ...args] = message.content.substring(prefix.length).split(/ +/);
		
		if(!commands.has(header))
			return;
		if(message.channel.type === "text" && !message.channel.permissionsFor(client.user || "")?.has(Permissions.FLAGS.SEND_MESSAGES))
		{
			let status;
			
			if(message.member?.hasPermission(Permissions.FLAGS.ADMINISTRATOR))
				status = "Because you're a server admin, you have the ability to change that channel's permissions to match if that's what you intended.";
			else
				status = "Try using a different channel or contacting a server admin to change permissions of that channel if you think something's wrong.";
			
			return message.author.send(`I don't have permission to send messages in ${message.channel.toString()}. ${status}`);
		}
		
		$.log(`${message.author.username}#${message.author.discriminator} executed the command "${header}" with arguments "${args}".`);
		
		// Subcommand Recursion //
		let command = commands.get(header);
		if(!command) return $.warn(`Command "${header}" was called but for some reason it's still undefined!`);
		const params: any[] = [];
		let isEndpoint = false;
		
		for(let param of args)
		{
			if(command.endpoint)
			{
				if(command.subcommands || command.user || command.number || command.any)
					$.warn(`An endpoint cannot have subcommands! Check ${prefix}${header} again.`);
				isEndpoint = true;
				break;
			}
			
			if(command.subcommands?.[param])
				command = command.subcommands[param];
			// Any Discord ID format will automatically format to a user ID.
			else if(command.user && (/\d{17,19}/.test(param)))
			{
				const id = param.match(/\d+/g)![0];
				command = command.user;
				try {params.push(await client.users.fetch(id))}
				catch(error) {return message.channel.send(`No user found by the ID \`${id}\`!`)}
			}
			// Disallow infinity and allow for 0.
			else if(command.number && (Number(param) || param === "0") && !param.includes("Infinity"))
			{
				command = command.number;
				params.push(Number(param));
			}
			else if(command.any)
			{
				command = command.any;
				params.push(param);
			}
			else
				params.push(param);
		}
		
		if(isEndpoint)
			return message.channel.send("Too many arguments!");
		
		// Execute with dynamic library attached. //
		// The purpose of using $.bind($) is to clone the function so as to not modify the original $.
		// The cloned function doesn't copy the properties, so Object.assign() is used.
		// Object.assign() modifies the first element and returns that, the second element applies its properties and the third element applies its own overriding the second one.
		command.execute(Object.assign($.bind($), {
			args: params,
			author: message.author,
			channel: message.channel,
			client: client,
			guild: message.guild,
			member: message.member,
			message: message
		}, $));
	});
	
	client.once("ready", () => {
		if(client.user)
		{
			$.ready(`Logged in as ${client.user.username}#${client.user.discriminator}.`);
			client.user.setActivity({
				type: "LISTENING",
				name: `${Config.prefix}help`
			});
		}
	});
	
	client.on("messageReactionRemove", unreact);
})()