const express = require('express');
const router = express.Router();
const pool = global.db_pool;
const log = global.log;

router.get('/getSession', async (req, res) => {
	if (!req.headers.authorization) return res.status(401).json({ status: 401, message: 'Missing Authorization Header', data: {} });
	const [hub] = await pool.query('SELECT * FROM hubs WHERE secretKey = ?', [req.headers.authorization]);
	if (!hub) return res.status(401).json({ status: 401, message: 'Invalid Authorization Header', data: {} });
	try {
		const pid = req.query.robloxPlayerId;
		if (!pid) return res.status(400).json({ status: 400, message: 'Missing Roblox Player ID' });
		log.info(`GET /hub/getSession?robloxPlayerId=${pid}`);
		const [row] = await pool.query('SELECT * FROM users WHERE robloxId = ?', [pid]);
		if (!row) {
			const pairingCode = Math.floor(100000 + Math.random() * 900000).toString();
			await pool.query('INSERT INTO users (robloxId, pairingCode) VALUES (?, ?)', [pid, pairingCode]);
			return res.status(409).json({ status: 409, message: `User is not paired! Run /link ${pairingCode} on Discord!`, pairingCode, data: {} });
		} else if (!row.discordId && !row.pairingCode) {
			const pairingCode = Math.floor(100000 + Math.random() * 900000).toString();
			await pool.query('UPDATE users SET pairingCode = ? WHERE robloxId = ?', [pairingCode, pid]);
			return res.status(409).json({ status: 409, message: `User is not paired! Run /link ${pairingCode} on Discord!`, pairingCode, data: {} });
		} else if (!row.discordId && row.pairingCode !== null) {
			return res.status(409).json({ status: 409, message: `User is not paired! Run /link ${row.pairingCode} on Discord!`, data: {} });
		} else {
			try {
				const products = await pool.query('SELECT * FROM products WHERE hubId = ?', [hub.id]);
				const purchases = await pool.query('SELECT * FROM purchases WHERE hubId = ?', [hub.id]);
				// Generate bestSeller object from purchases. Find what product id has the most sales, then make the object
				const purchaseCounts = purchases.reduce((acc, purchase) => {
					acc[purchase.productId] = (acc[purchase.productId] || 0) + 1;
					return acc;
				}, {});
				
				const bestSellerProductId = Object.keys(purchaseCounts).reduce((a, b) => purchaseCounts[a] > purchaseCounts[b] ? a : b, null);
				const bestSellerProduct = products.find(product => product.id == bestSellerProductId);
				const bestSeller = bestSellerProduct ? {
					productID: bestSellerProduct.id,
					name: bestSellerProduct.name,
					description: bestSellerProduct.description,
					devproduct_id: (bestSellerProduct.stock == 0) ? 0 : bestSellerProduct.devProductID,
					decalID: bestSellerProduct.decalId || "0",
					stock: bestSellerProduct.stock == -1 ? false : bestSellerProduct.stock,
					onsale: bestSellerProduct.stock == -1 || bestSellerProduct.stock > 0 ? true : false,
					category: bestSellerProduct.stock == -1 || bestSellerProduct.stock > 0 ? bestSellerProduct.category : "Out of Stock",
					rating: {
						currentScore: 0,
						maxScore: 0,
						amountOfReviews: 0
					},
					tags: [],
					playerData: {
						robloxId: pid,
						ownsProduct: purchases.some(purchase => purchase.productId == bestSellerProduct.id && purchase.robloxId == pid)
					}
				} : {};

				// generate array of products
				const respData = JSON.stringify({
					status: 200,
					message: "OK",
					data: {
						userData: {
							connectedUsername: row.discordDisplayName,
						},
						hubData: {
							id: hub.id,
							name: hub.name,
							description: {
								shortDescription: hub.shortDescription,
								longDescription: hub.longDescription,
							},
							config: {
								allowGiftPurchases: hub.allowGiftPurchase ? true : false,
							},
							statistics: {
								totalSales: purchases.length,
							},
							regulatory: {
								termsOfService: hub.tos
							},
						},
						productsData: {
							bestsellerProduct: bestSeller,
							allProducts: products.map(product => ({
								productID: product.id,
								name: product.name,
								description: product.description,
								devproduct_id: (product.stock == 0) ? 0 : product.devProductID,
								decalID: product.decalId || "0",
								stock: (product.stock == -1 || purchases.some(purchase => purchase.productId == product.id && purchase.robloxId == pid)) ? false : product.stock,
								onsale: product.stock == -1 || product.stock > 0 ? true : false,
								category: product.stock == -1 || product.stock > 0 ? product.category : "Out of Stock",
								rating: {
									currentScore: 0,
									maxScore: 0,
									amountOfReviews: 0
								},
								tags: [],
								playerData: {
									robloxId: pid,
									ownsProduct: purchases.some(purchase => purchase.productId == product.id && purchase.robloxId == pid)
								}
							})),
						},
						robloxGame: {
							musicId: hub.musicId,
						},
						requestedAt: new Date().toISOString(),
					}
				}, (_, v) => typeof v === 'bigint' ? v.toString() : v)

				return res.status(200).send(respData)
			} catch (error) {
				log.error(error);
				return res.status(500).json({ status: 500, message: 'Internal Server Error', data: {} });
			}
		}
	} catch (error) {
		log.error(error);
		return res.status(500).json({ status: 500, message: 'Internal Server Error', data: {} });
	}
});

module.exports = router;