import express, { Request, Response } from 'express';
import { prisma, __path, log } from '../../../../index.js';
import { UploadedFile } from 'express-fileupload';
import { parse, transform } from 'csv';
import { Status, Category, PrismaPromise } from '@prisma/client';

export default (req: Request, res: Response) => {
	// Decide wether its post or get
	if (req.method === 'POST') {
		// Handle file upload and import
		console.log(req.files)
		if (!req.files || Object.keys(req.files).length === 0) {
			return res.status(400).send('No files were uploaded.');
		}

		const file: UploadedFile = req.files.formFile as UploadedFile;
		const csv = file.data.toString();
		parse(csv, { columns: true }, function (err, records) {
			if (err) {
				res.send(err);
				return;
			}
			// Find all categories and save them into a set
			const categories = new Set<string>();
			records.forEach((record: any) => {
				categories.add(record.category);
			});
			// Remove categories that already exists in the database
			prisma.category.findMany({
				where: {
					name: {
						in: Array.from(categories)
					}
				}
			}).then((values) => {
				values.forEach((value) => {
					categories.delete(value.name);
				});

				const categoryPromises: PrismaPromise<Category>[] = [];
				categories.forEach((category: string) => {
					const promise = prisma.category.create({
						data: {
							name: category
						}
					})
					categoryPromises.push(promise);
				});
				Promise.all(categoryPromises).then((values) => {
					// Create items
					const listOfPromises = [];

					for (let i = 0; i < records.length; i++) {
						const record = records[i];
						const promise = prisma.item.create({
							data: {
								name: record.name,
								Amount: parseInt(record.amount),
								Comment: record.comment,
								category: {
									connect: {
										name: record.category
									}
								},
								SKU: record.sku,
								manufacturer: record.manufacturer,
								status: Status.normal,
								importedBy: "CSV Import"
							}
						});
						listOfPromises.push(promise);
					}
					Promise.all(listOfPromises).then((values) => {
						console.log(values);
						res.send('ok');
					}).catch((err) => {
						res.send('failed to create items');
						log.db.error(err);
						return;
					});
				}).catch((err) => {
					// res.send('failed to create categories');
					log.db.error(err);

				});


			}).catch((err) => {
				res.send('failed to find categories');
				log.db.error(err);
				return;
			});

		});


	} else {
		// Render page
		res.render(__path + '/src/frontend/manage/imports/csvImport.eta.html');
	}

};