require("dotenv").config();
const { DISCORD_TOKEN, MATRIX_BASE_URL, MATRIX_SERVER_NAME, MATRIX_ADMIN_TOKEN } = process.env;
const colors = require("colors");
const Path = require("path")
const Discord = require("discord.js");
const Client = new Discord.Client({
	intents: []
});
const {
	REST,
	Routes
} = require('discord.js');

const rest = new REST({
	version: '10'
}).setToken(DISCORD_TOKEN);

var whoami;

var matrixHeaders = {
	"Authorization": `Bearer ${MATRIX_ADMIN_TOKEN}`
};

Client.on("ready", async () => {
	console.log(`${colors.cyan("[Info]")} Logged in as ${Client.user.displayName}`);

	const commands = [
		{
			"name": "matrix-register",
			"description": "Create an account on matrix.litenet.tel",
			"type": 1,
			"options": [
				{
					"name": "username",
					"description": "@<username>:litenet.tel. Be warned, you can't change this once it's set.",
					"type": Discord.ApplicationCommandOptionType.String,
					"required": true
				}
			]
		}
	]

	//Register commands
	await (async () => {
		try {
			console.log(`${colors.cyan("[Info]")} Registering Commands...`)
			//Global
			await rest.put(Routes.applicationCommands(Client.user.id), { body: commands })
			console.log(`${colors.cyan("[Info]")} Successfully registered commands.`);
		} catch (error) {
			console.error(error);
		}
	})();

	fetch(`${MATRIX_BASE_URL}/_matrix/client/v3/account/whoami`, {
		headers: matrixHeaders
	}).then(async (response) => {
		whoami = await response.json();
	})
});
const usernameFilter = /^[a-z0-9._=\-\/+]+$/;

const formatUsername = (input) => {
	if (!usernameFilter.test(input)) throw new Error("Username does not match allowed characters");
	return `@${input}:${MATRIX_SERVER_NAME}`
}

function generatePassword(length) {
	// Define the character set
	const characters = 'abcdefghijklmnopqrstuvwxyz0123456789._=-/+';
	
	// Ensure the length is valid
	if (length <= 0) {
		throw new Error('Password length must be greater than 0');
	}

	let password = '';
	
	// Generate the password
	for (let i = 0; i < length; i++) {
	  const randomIndex = Math.floor(Math.random() * characters.length);
		password += characters[randomIndex];
	}
	
	return password;
}

async function uploadMediaToMatrix(url, filename, mimetype) {
	var data = await fetch(url);
	const response = await fetch(`${MATRIX_BASE_URL}/_matrix/media/v3/upload?filename=${filename}`, {
		method: "POST",
		headers: {
			"Authorization": `Bearer ${MATRIX_ADMIN_TOKEN}`,
			"Content-Type": mimetype
		},
		body: await data.arrayBuffer()
	});
	const json = await response.json();
	return json;
}

Client.on("interactionCreate", async (interaction) => {
	if (!interaction.isCommand()) return;
	switch (interaction.commandName) {
		case "matrix-register":
			const inputUsername = interaction.options.getString("username");
			if (!usernameFilter.test(inputUsername)) return interaction.reply({ephemeral: true, content: "Your username contains invalid characters.\nYour username MUST contain only the characters `a-z`, `0-9`, `.`, `_`, `=`, `-`, `/`, and `+`."});
			
			const mxid = formatUsername(inputUsername);

			// Check if the user exists
			const userCheck = await fetch(`${MATRIX_BASE_URL}/_synapse/admin/v2/users/${mxid}`, {
				headers: {
					"Authorization": `Bearer ${MATRIX_ADMIN_TOKEN}`
				}
			});
			if (userCheck.ok) return interaction.reply({ephemeral: true, content: "That username is taken! Please choose a different one."});

			// Check if user already has a matrix account
			const dataStoreCheck = await fetch(`${MATRIX_BASE_URL}/_matrix/client/v3/user/${whoami.user_id}/account_data/tel.litenet.discordids.${interaction.user.id}`,{
				headers: matrixHeaders
			})
			if(dataStoreCheck.status !== 404) return interaction.reply({ephemeral: true, content: `You already have an account dingus! It's \`${(await dataStoreCheck.json()).matrix_id}\`\nIf you believe this is an error, please contact an admin!`});
			const newPassword = generatePassword(32);

			// Emma@Rory&: Upload avatar to matrix:
			const avatar = interaction.user.displayAvatarURL({size: 4096});
			var filename = Path.basename(avatar);
			var mimetype;
			switch (filename.split(".").pop()) {
				case "png":
					mimetype = "image/png";
					break;
				case "jpg":
				case "jpeg":
					mimetype = "image/jpeg";
					break;
				case "gif":
					mimetype = "image/gif";
					break;
				case "webp":
					mimetype = "image/webp";
					break;
				default:
					mimetype = "image/png";
					break;
			}

			let mxcUri = undefined;
			await uploadMediaToMatrix(avatar, filename, mimetype).then((response) => {
				mxcUri = response.content_uri;
			}).catch((error) => {
				console.error("Error while uploading discord avatar to matrix:", error);
			});


			// Create the user
			const createUser = await fetch(`${MATRIX_BASE_URL}/_synapse/admin/v2/users/${mxid}`, {
				method: "PUT",
				headers: {
					"Authorization": `Bearer ${MATRIX_ADMIN_TOKEN}`
				},
				body: JSON.stringify({
					"password": newPassword,
					"displayname": interaction.user.displayName,
					avatar_url: mxcUri
				})
			});

			if (!userCheck.status.toString() == "201") {
				const createUserError = await createUser.json()
				return interaction.reply({
					ephemeral: true,
					content: `An error has occured!\n${createUserError.errcode}: ${createUserError.error}`
				})
			}
			
			// Send the user their credentials
			interaction.user.send({content: `Your matrix account has been created!\nUsername: \`${mxid}\`\nPassword: ||\`${newPassword}\`||\nServer: ${MATRIX_SERVER_NAME}\n\nYou can find a list of Matrix clients [here!](https://matrix.org/ecosystem/clients/)`}).then(() => {
				interaction.reply({ephemeral: true, content: "User created! Check your DMs!"});
			}).catch((error) => {
				interaction.reply({ephemeral: true, content: `Your matrix account has been created!\nUsername: \`${mxid}\`\nPassword: ||\`${newPassword}\`||\nServer: ${MATRIX_SERVER_NAME}\n\nYou can find a list of Matrix clients [here!](https://matrix.org/ecosystem/clients/)\n\nYour DMs were disabled, so we weren't able to send you these credentials!\n***MAKE SURE YOU SAVE THEM***`});
			})

			// Store the discord id and matrix id
			fetch(`${MATRIX_BASE_URL}/_matrix/client/v3/user/${whoami.user_id}/account_data/tel.litenet.discordids.${interaction.user.id}`,{
				headers: matrixHeaders,
				body: JSON.stringify({
					matrix_id: mxid,
					discord_id: interaction.user.id
				}),
				method: "PUT"
			})
			break;
	}
})

Client.login(DISCORD_TOKEN);