import db from "db/connection";
import { timeouts, users } from "db/schema";
import {
	and,
	between,
	count,
	desc,
	eq,
	type InferSelectModel,
	inArray,
	ne,
	type SQL,
	sql,
} from "drizzle-orm";
import { itemarray, type items } from "items";
import { ANIVNAMES } from "lib/handleAnivMessage";
import type User from "user";

/** Use this function to both ensure existance and to retreive data */
export async function getUserRecord(user: User) {
	const data = await db.query.users.findFirst({
		where: eq(users.id, parseInt(user.id, 10)),
	});
	if (!data) return createUserRecord(user);

	if (
		Object.keys(data.inventory).sort().toString() !==
		itemarray.sort().toString()
	) {
		// If the items in the user inventory are missing an item.
		itemarray.forEach((key) => {
			if (!(key in data.inventory)) data.inventory[key] = 0;
		});
	}

	return data;
}

export async function getAllUserRecords() {
	return await db.select().from(users);
}

async function createUserRecord(user: User) {
	return await db
		.insert(users)
		.values({
			id: parseInt(user.id, 10),
			username: user.username,
		})
		.returning()
		.then((a) => {
			if (!a[0]) throw Error("Something went horribly wrong");
			return a[0];
		});
}

export type UserRecord = InferSelectModel<typeof users>;

export async function updateUserRecord(user: User, newData: UserRecord) {
	await db
		.update(users)
		.set(newData)
		.where(eq(users.id, parseInt(user.id, 10)));
	return true;
}

export async function getBalanceLeaderboard() {
	return await db.select().from(users).orderBy(desc(users.balance)).limit(10);
}

export async function getKDLeaderboard(monthData?: string) {
	let condition: SQL<unknown> | undefined = ne(timeouts.item, "silverbullet");
	if (monthData) {
		const begin = Date.parse(monthData);
		const end = new Date(begin).setMonth(new Date(begin).getMonth() + 1);
		condition = and(
			condition,
			between(timeouts.created, new Date(begin), new Date(end)),
		);
	}

	const usersGotShot = await db
		.select({
			userId: users.id,
			amount: count(timeouts.target),
		})
		.from(users)
		.innerJoin(timeouts, eq(users.id, timeouts.target))
		.groupBy(users.id)
		.having(sql`count(${timeouts.id}) > 5`)
		.where(condition);

	const usersThatShot = await db
		.select({
			userId: users.id,
			amount: count(timeouts.user),
		})
		.from(users)
		.innerJoin(timeouts, eq(users.id, timeouts.user))
		.groupBy(users.id)
		.where(
			and(
				condition,
				inArray(
					users.id,
					usersGotShot.map((a) => a.userId),
				),
			),
		);

	const lookup = new Map(usersThatShot.map((a) => [a.userId, a.amount]));
	const result = usersGotShot.map((user) => ({
		userId: user.userId,
		KD: lookup.get(user.userId)! / user.amount,
	}));

	result.map((user) => {
		if (Number.isNaN(user.KD)) user.KD = 0;
		return user;
	});

	return result;
}

type ItemCounts = Record<items, number>;

export async function getTotalItemCounts(): Promise<ItemCounts> {
	const allUsers = await db
		.select({ username: users.username, inventory: users.inventory })
		.from(users);

	const filteredUsers = allUsers.filter(
		(user) =>
			!Array.from<string>(ANIVNAMES).includes(user.username.toLowerCase()),
	);

	const counts = itemarray.reduce((acc, item) => {
		acc[item] = filteredUsers.reduce((sum, user) => {
			return sum + (user.inventory[item] || 0);
		}, 0);
		return acc;
	}, {} as ItemCounts);

	return counts;
}