const axios = require("axios");
const util = require('util');
const exec = util.promisify(require('child_process').exec);
const utils = require('./utils');

const conversions = {
    "Beutel": { unit: 'stk', factor: 1 },
    "Blatt": { unit: 'stk', factor: 1 },
    "Bund": { unit: 'stk', factor: 1 },
    "g": { unit: 'g', factor: 1},
    "Gramm": { unit: 'g', factor: 1},
    "kg": { unit: 'g', factor: 1000},
    "Kilogramm": { unit: 'g', factor: 1},
    "l": { unit: 'ml', factor: 1000},
    "Liter": { unit: 'ml', factor: 1000},
    "cm": { unit: 'cm', factor: 1},
    "m": { unit: 'cm', factor: 100},
    "Meter": { unit: 'cm', factor: 100},
    "Milliliter": { unit: 'ml', factor: 1},
    "ml": { unit: 'ml', factor: 1},
    "Paar": { unit: 'stk', factor: 1 },
    "Packung": { unit: 'stk', factor: 1 },
    "Portion": { unit: 'stk', factor: 1 },
    "Rollen": { unit: 'stk', factor: 1 },
    "Stk": { unit: 'stk', factor: 1 },
    "Stück": { unit: 'stk', factor: 1 },
    "stück": { unit: 'stk', factor: 1 },
    "Teebeutel": { unit: 'stk', factor: 1 },
    "Waschgang": { unit: 'wg', factor: 1 },
    "Zentimeter": { unit: 'cm', factor: 1 },
};

exports.getCanonical = function (item, today) {
    let quantity = 1, unit = "kg";
    if (item.grammage && item.grammage.length > 0) {
        let grammage = item.grammage.trim().replace(/\([^)]*\)/g, '').replace(",", ".").trim();
        let multiplier = 1;
        if (grammage.indexOf("x") != -1) {
            let tokens = grammage.split("x")
            multiplier = Number.parseFloat(tokens[0]);
            grammage = tokens[1];
        }

        let tokens = grammage.split(" ");
        if (tokens.length > 1) {
            quantity = Number.parseFloat(tokens[0]);
            unit = tokens[1];
        } else {
            [quantity, unit] = grammage.match(/^(\d+(?:\.\d+)?)(\D+)$/).slice(1);
            quantity = Number.parseFloat(quantity);
        }
        quantity *= multiplier;
    } else {
        quantity = 1; unit = "Stk";
    }

    let price = Number.parseFloat(item.currentPrice.split(" ")[0].replace(",", "."));
    return utils.convertUnit({
        id: item.id,
        name: item.name,
        price,
        priceHistory: [{ date: today, price }],
        isWeighted: false,
        unit,
        quantity,
        bio: false,
        url: "",
    }, conversions, "reweDe");
}

exports.fetchData = async function () {
    // For some unholy reason, Axios returns 403 when accessing the endpoint
    // Hack: use curl...
    /*const agent = new https.Agent({
        rejectUnauthorized: false
    });
    let axiosNoDefaults = axios.create({ headers: {} });
    const headers = {
        'Rd-Service-Types': 'PICKUP',
        'Rd-Market-Id': '440405',
        "User-Agent": "curl/7.84.0"
    }
    return (await axiosNoDefaults.get('https://mobile-api.rewe.de/api/v3/product-search?searchTerm=*&page=1&sorting=RELEVANCE_DESC&objectsPerPage=250&marketCode=440405&serviceTypes=PICKUP', { headers, httpsAgent: agent })).data;*/

    try {
        await exec("curl --version")
    } catch(e) {
        console.log("ERROR: Can't fetch REWE-DE data, no curl installed.");
        return [];
    }

    let pageId = 1;
    let result = (await exec(`curl -s "https://mobile-api.rewe.de/api/v3/product-search\?searchTerm\=\*\&page\=${pageId++}\&sorting\=RELEVANCE_DESC\&objectsPerPage\=250\&marketCode\=440405\&serviceTypes\=PICKUP" -H "Rd-Service-Types: PICKUP" -H "Rd-Market-Id: 440405"`)).stdout;
    const firstPage = JSON.parse(result);
    const totalPages = firstPage.totalPages;
    const items = [...firstPage.products];
    for (let i = 2; i <= totalPages; i++) {
        items.push(...JSON.parse((await exec(`curl -s "https://mobile-api.rewe.de/api/v3/product-search\?searchTerm\=\*\&page\=${pageId++}\&sorting\=RELEVANCE_DESC\&objectsPerPage\=250\&marketCode\=440405\&serviceTypes\=PICKUP" -H "Rd-Service-Types: PICKUP" -H "Rd-Market-Id: 440405"`)).stdout).products);
    }
    return items;
}