// Get CORPUS data from Network Rail and format the data for OwlBoard

// Network Rail Datafeed user and pass must be stored in `/srv/keys/owlboard/keys.config.js`

// FUNCTIONS
//  init()   : Exported: Uses the internal functions to return a clean CORPUS file.
//  get()    : Get the CORPUS data from Network Rail as a gzip file.
//  extract(): Extract the CORPUS JSON file from the GZIP file.
//  clean()  : Cleans the CORPUS data, removing unneccesary keys from the data.

const keys    = require('/srv/keys/owlboard/keys.configs');
const axios   = require('axios');
const zlib    = require('zlib');

async function init() {
    var gzipData = await get();
    console.log(gzipData);
    var rawData = await extract(gzipData);
    console.log(rawData);
    var cleanData = await clean(rawData);
    console.log(cleanData)
    return cleanData;
}

async function get() {
    authHead = Buffer.from(`${keys.nr_user}:${keys.nr_pass}`).toString('base64');
    const url = 'https://datafeeds.networkrail.co.uk/ntrod/SupportingFileAuthenticate?type=CORPUS'
    const options = {
        method: 'get',
        timeout: 20000,
        headers: {'Authorization': `Basic ${authHead}`},
        responseType: 'arraybuffer'
    };
    var { output } = await axios.get(url, options)
    console.log(output)
    return output;
}

async function extract(input) {
    var { data } = zlib.Gunzip(input);
    let string = data.toString()
    let obj = JSON.parse(string)
    //console.log(obj);
    return obj; // Find out how to get data out of callback -> See pinned tab on laptop2.ws
}

async function clean() {
    return "Empty Function: clean()"
}

module.exports = {
    init
}