// ==UserScript==
// @name        dzunlock
// @namespace   io.github.uhwot.dzunlock
// @description enables deezer hifi features lol
// @author      uh wot
// @version     1.3.2
// @license     GPL-3.0-only
// @homepageURL https://git.freezer.life/uhwot/dzunlock
// @downloadURL https://git.freezer.life/uhwot/dzunlock/raw/branch/master/dzunlock.user.js
// @icon        https://cdns-files.dzcdn.net/cache/images/common/favicon/favicon-96x96.852baf648e79894b668670e115e4a375.png
// @include     /^https:\/\/www\.deezer\.com\/[a-z]{2}\/($|track|album|artist|playlist|episode|show|profile|channels|podcasts|radio)/
// @match       https://www.deezer.com/search/*
// @match       https://www.deezer.com/account/*
// @match       https://www.deezer.com/concert/*
// @match       https://www.deezer.com/smarttracklist/*
// @require     https://cdnjs.cloudflare.com/ajax/libs/aes-js/3.1.2/index.min.js
// @grant       GM_getValue
// @run-at      document-start
// ==/UserScript==

const debug = false

function log(...args) {
    if (debug) {
        return console.log(...args)
    }
}

// https://github.com/werk85/fetch-intercept/blob/develop/src/attach.js modified for browser support
let interceptors = [];

function interceptor(fetch, ...args) {
    const reversedInterceptors = interceptors.reduce((array, interceptor) => [interceptor].concat(array), []);
    let promise = Promise.resolve(args);

    // Register request interceptors
    reversedInterceptors.forEach(({ request, requestError }) => {
        if (request || requestError) {
            promise = promise.then(args => request(...args), requestError);
        }
    });

    // Register fetch call
    promise = promise.then(args => {
        const request = new Request(...args);
        return fetch(request).then(response => {
            response.request = request;
            return response;
        }).catch(error => {
            error.request = request;
            return Promise.reject(error);
        });
    });

    // Register response interceptors
    reversedInterceptors.forEach(({ response, responseError }) => {
        if (response || responseError) {
            promise = promise.then(response, responseError);
        }
    });

    return promise;
}

unsafeWindow.fetch = (function (fetch) {
    return function (...args) {
        return interceptor(fetch, ...args);
    };
})(unsafeWindow.fetch);

fetchIntercept = {
    register: function (interceptor) {
        interceptors.push(interceptor);
        return () => {
            const index = interceptors.indexOf(interceptor);
            if (index >= 0) {
                interceptors.splice(index, 1);
            }
        };
    },
    clear: function () {
        interceptors = [];
    }
};

// main code starts here

const playerTokenKey = [102, 228, 95, 242, 215, 50, 122, 26, 57, 216, 206, 38, 164, 237, 200, 85]
const cipher = new aesjs.ModeOfOperation.ecb(playerTokenKey)

const quality_to_format = {
    "standard": "MP3_128",
    "high": "MP3_320",
    "lossless": "FLAC"
}

function str2bin(str) {
    return Array.from(str).map(function (item) {
        return item.charCodeAt(0);
    })
}

function bin2str(bin) {
    return String.fromCharCode.apply(String, bin);
}

function decryptHex(hex) {
    hex = aesjs.utils.hex.toBytes(hex)
    return bin2str(cipher.decrypt(hex)).replace(/\0+$/, '')     // removes zero-padding
}

function encryptHex(str) {
    // zero-padding
    if (str.length % 16) {
        str += '\x00'.repeat(16 - str.length % 16)
    }

    return aesjs.utils.hex.fromBytes(cipher.encrypt(str2bin(str)))
}

function playerTokenPatch(playerToken) {
    playerToken = JSON.parse(decryptHex(playerToken))

    // enables 320/flac quality selection
    playerToken.audio_qualities.wifi_streaming = ['low', 'standard', 'high', 'lossless']
    // disables previews
    playerToken.streaming = true
    playerToken.limited = false

    log(playerToken)

    return encryptHex(JSON.stringify(playerToken))
}

window.addEventListener('DOMContentLoaded', (_) => {
    unsafeWindow.dzPlayer.setTrackList = (function (old) {
        return function (data, ...args) {
            // needed for deezer's player to accept 320/flac responses

            for (let i = 0; i < data.data.length; i++) {
                const id = parseInt(data.data[i].SNG_ID)
                if (id >= 0) {      // don't change filesizes on user-upped tracks
                    data.data[i].FILESIZE_MP3_320 = '1'
                    data.data[i].FILESIZE_FLAC = '1'
                }
            }

            log(data)

            return old(data, ...args)
        };
    })(unsafeWindow.dzPlayer.setTrackList);
});

fetchIntercept.register({
    request: function (url, config) {
        // Modify the url or config here
        if (url === 'https://media.deezer.com/v1/get_url') {
            const quality = unsafeWindow.dzPlayer.control.getAudioQuality()
            const track = unsafeWindow.dzPlayer.getCurrentSong()
            const id = parseInt(track.SNG_ID)

            let is_subbed = !unsafeWindow.dzPlayer.user_status.can_subscribe
            let is_quality_available = unsafeWindow.dzPlayer.user_status.audio_qualities.wifi_download.includes(quality)
            // STREAM_ADS_AVAILABLE is used to check if track is restricted to premium/hifi
            if (track.RIGHTS.STREAM_ADS_AVAILABLE !== true && !is_subbed) {
                is_quality_available = false
            }

            if (id >= 0 && !is_quality_available) {
                const media_server = GM_getValue('media_server', 'https://dzmedia.herokuapp.com')
                url = `${media_server}/get_url`

                const body = {
                    formats: ['FLAC', 'MP3_320', 'MP3_128', 'MP3_64', 'MP3_MISC'],
                    ids: [id]
                }

                for (let i = 0; i < body.formats.length; i++) {
                    if (body.formats[0] !== quality_to_format[quality]) {
                        body.formats.shift()
                    } else {
                        break
                    }
                }

                config.body = JSON.stringify(body)
            }
        }

        return [url, config];
    },

    requestError: function (error) {
        // Called when an error occured during another 'request' interceptor call

        return Promise.reject(error);
    },

    response: async function (response) {
        // Modify the response object

        if (response.url.startsWith('https://www.deezer.com/ajax/gw-light.php?method=deezer.getUserData')) {
            let json = await response.json()

            // removes upgrade popup stuff
            json.results.USER.ENTRYPOINTS = {}
            // needed to play premium-restricted albums like https://www.deezer.com/album/801279
            json.results.OFFER_ID = 600
            // disables ads
            json.results.USER.OPTIONS.ads_display = false
            json.results.USER.OPTIONS.ads_audio = false

            json.results.PLAYER_TOKEN = playerTokenPatch(json.results.PLAYER_TOKEN)

            log(json)

            return new Response(JSON.stringify(json))
        }

        if (response.url.startsWith('https://www.deezer.com/ajax/gw-light.php?method=log.listen')) {
            const json = await response.json()

            if (typeof json.results === 'string') {
                json.results = playerTokenPatch(json.results)
            }

            return new Response(JSON.stringify(json))
        }

        return response;
    },

    responseError: function (error) {
        // Handle an fetch error

        return Promise.reject(error);
    }
});