import type {NextApiRequest, NextApiResponse} from "next";
import {app} from "@/firebase";
import {withIronSessionApiRoute} from "iron-session/next";
import {sessionOptions} from "@/lib/session";
import {v4} from "uuid";
import {CorporateUser, Group, Type, User} from "@/interfaces/user";
import {createUserWithEmailAndPassword, getAuth} from "firebase/auth";
import ShortUniqueId from "short-unique-id";
import {getGroup, getGroups, getUserCorporate, getUserGroups, getUserNamedGroup} from "@/utils/groups.be";
import {uniq} from "lodash";
import {getSpecificUsers, getUser} from "@/utils/users.be";
import client from "@/lib/mongodb";

const DEFAULT_DESIRED_LEVELS = {
	reading: 9,
	listening: 9,
	writing: 9,
	speaking: 9,
};

const DEFAULT_LEVELS = {
	reading: 0,
	listening: 0,
	writing: 0,
	speaking: 0,
};

const auth = getAuth(app);
const db = client.db(process.env.MONGODB_DB);

export default withIronSessionApiRoute(handler, sessionOptions);

const getUsersOfType = async (admin: string, type: Type) => {
	const groups = await getUserGroups(admin);
	const participants = groups.flatMap((x) => x.participants);
	const users = await getSpecificUsers(participants);

	return users.filter((x) => x?.type === type).map((x) => x?.id);
};

async function handler(req: NextApiRequest, res: NextApiResponse) {
	if (req.method === "POST") return post(req, res);

	return res.status(404).json({ok: false});
}

async function post(req: NextApiRequest, res: NextApiResponse) {
	const maker = req.session.user;
	if (!maker) {
		return res.status(401).json({ok: false, reason: "You must be logged in to make user!"});
	}

	const corporateCorporate = await getUserCorporate(maker.id);

	const {email, passport_id, password, type, groupID, expiryDate, corporate} = req.body as {
		email: string;
		password?: string;
		passport_id: string;
		type: string;
		groupID?: string;
		corporate?: string;
		expiryDate: null | Date;
	};
	// cleaning data
	delete req.body.passport_id;
	delete req.body.groupID;
	delete req.body.expiryDate;
	delete req.body.password;
	delete req.body.corporate;

	await createUserWithEmailAndPassword(auth, email.toLowerCase(), !!password ? password : passport_id)
		.then(async (userCredentials) => {
			const userId = userCredentials.user.uid;

			const profilePicture = !corporateCorporate ? "/defaultAvatar.png" : corporateCorporate.profilePicture;

			const user = {
				...req.body,
				bio: "",
				id: userId,
				type: type,
				focus: "academic",
				status: "active",
				desiredLevels: DEFAULT_DESIRED_LEVELS,
				profilePicture,
				levels: DEFAULT_LEVELS,
				isFirstLogin: false,
				isVerified: true,
				registrationDate: new Date(),
				subscriptionExpirationDate: expiryDate || null,
				...((maker.type === "corporate" || maker.type === "mastercorporate") && type === "corporate"
					? {
							corporateInformation: {
								companyInformation: {
									name: maker.corporateInformation?.companyInformation?.name || "N/A",
									userAmount: 0,
								},
							},
					  }
					: {}),
			};

			const uid = new ShortUniqueId();
			const code = uid.randomUUID(6);

			await db.collection("users").insertOne(user);
			await db.collection("codes").insertOne({
				code,
				creator: maker.id,
				expiryDate,
				type,
				creationDate: new Date(),
				userId,
				email: email.toLowerCase(),
				name: req.body.name,
				...(!!passport_id ? {passport_id} : {}),
			});

			if (type === "corporate") {
				const students = maker.type === "corporate" ? await getUsersOfType(maker.id, "student") : [];
				const teachers = maker.type === "corporate" ? await getUsersOfType(maker.id, "teacher") : [];

				const defaultTeachersGroup: Group = {
					admin: userId,
					id: v4(),
					name: "Teachers",
					participants: teachers,
					disableEditing: true,
				};

				const defaultStudentsGroup: Group = {
					admin: userId,
					id: v4(),
					name: "Students",
					participants: students,
					disableEditing: true,
				};

				await db.collection("groups").insertMany([defaultStudentsGroup, defaultTeachersGroup]);
			}

			if (!!corporate) {
				const corporateUser = await db.collection("users").findOne<CorporateUser>({email: corporate.trim().toLowerCase()});

				if (!!corporateUser) {
					await db.collection("codes").updateOne({code}, {$set: {creator: corporateUser.id}});
					const typeGroup = await db
						.collection("groups")
						.findOne<Group>({creator: corporateUser.id, name: type === "student" ? "Students" : "Teachers"});

					if (!!typeGroup) {
						if (!typeGroup.participants.includes(userId)) {
							await db.collection("groups").updateOne({id: typeGroup.id}, {$set: {participants: [...typeGroup.participants, userId]}});
						}
					} else {
						const defaultGroup: Group = {
							admin: corporateUser.id,
							id: v4(),
							name: type === "student" ? "Students" : "Teachers",
							participants: [userId],
							disableEditing: true,
						};

						await db.collection("groups").insertOne(defaultGroup);
					}
				}
			}

			if (maker.type === "corporate") {
				await db.collection("codes").updateOne({code}, {$set: {creator: maker.id}});
				const typeGroup = await getUserNamedGroup(maker.id, type === "student" ? "Students" : "Teachers");

				if (!!typeGroup) {
					if (!typeGroup.participants.includes(userId)) {
						await db.collection("groups").updateOne({id: typeGroup.id}, {$set: {participants: [...typeGroup.participants, userId]}});
					}
				} else {
					const defaultGroup: Group = {
						admin: maker.id,
						id: v4(),
						name: type === "student" ? "Students" : "Teachers",
						participants: [userId],
						disableEditing: true,
					};

					await db.collection("groups").insertOne(defaultGroup);
				}
			}

			if (!!corporateCorporate && corporateCorporate.type === "mastercorporate" && type === "corporate") {
				const corporateGroup = await getUserNamedGroup(corporateCorporate.id, "Corporate");

				if (!!corporateGroup) {
					if (!corporateGroup.participants.includes(userId)) {
						await db
							.collection("groups")
							.updateOne({id: corporateGroup.id}, {$set: {participants: [...corporateGroup.participants, userId]}});
					}
				} else {
					const defaultGroup: Group = {
						admin: corporateCorporate.id,
						id: v4(),
						name: "Corporate",
						participants: [userId],
						disableEditing: true,
					};

					await db.collection("groups").insertOne(defaultGroup);
				}
			}

			if (!!groupID) {
				const group = await getGroup(groupID);
				if (!!group) await db.collection("groups").updateOne({id: group.id}, {$set: {participants: [...group.participants, userId]}});
			}

			console.log(`Returning - ${email}`);
			return res.status(200).json({ok: true});
		})
		.catch((error) => {
			if (error.code.includes("email-already-in-use")) return res.status(403).json({error, message: "E-mail is already in the platform."});

			console.log(`Failing - ${email}`);
			console.log(error);
			return res.status(401).json({error});
		});
}