import * as express from 'express';
import Article from '../models/article';
import { IArticle } from '../interfaces/article';
import { Router, Request, Response } from "express";
import User from '../models/user';
import { IUser } from '../interfaces/user';

const router: Router = express.Router();

router.get('/', async (req: Request, res: Response) => {
    try {
        const offset: number = req.query.offset ? parseInt(req.query.offset) : 0;
        const limit: number = req.query.limit ? parseInt(req.query.limit) : 0;
        const filter: {[key: string]: any} = req.query.filter ? JSON.parse(req.query.filter) : {};
        const sort: {[key: string]: number} = (req.query.sort && req.query.order)
            ? {[req.query.sort]: req.query.order}
            : {};

        const articles: IArticle[] = await Article
            .find(filter)
            .skip(offset)
            .limit(limit)
            .sort(sort)
            .populate({
                path: 'author',
                select: '-articles'
            });

        if (articles.length === 0) {
            res.sendStatus(404);
            return;
        }

        if (limit > 0) {
            //Content-Range: <unit> <range-start>-<range-end>/<size>
            const contenRangeHeader: string = 'articles '  + (offset + 1) + '-' + (offset + articles.length) + '/' + articles.length;
            res.setHeader('Content-Range', contenRangeHeader);
        }

        res.json(articles);
    } catch (error) {
        res.status(500).json({ error });
    }
});

// ...