animeheaven

const got = require('got');
const querystring = require('querystring');

const ANIME_NAME = 'A Certain Magical Index'; // This is case-sensitive and must be exact
const ANIME_EPISODE = 2;
const ENCRYPTION_KEY = 'ysdgetcfc'; // Seems to be static? It works for all the series I've tried

const QUERY = querystring.stringify({
    a: ANIME_NAME,
    e: ANIME_EPISODE
});

const STREAM_1_REGEX = /var soienfu="(.*)";/;
const STREAM_2_REGEX = /var iusfdb="(.*)";/;
const STREAM_3_REGEX = /var ufbjhse="(.*)";/;

// https://stackoverflow.com/a/4209150
String.prototype.decodeEscapeSequence = function() {
    return this.replace(/\\x([0-9A-Fa-f]{2})/g, function() {
        return String.fromCharCode(parseInt(arguments[1], 16));
    });
};

(async () => {
    const streams = {};

    console.log(`Searching for streams for ${ANIME_NAME}, episode ${ANIME_EPISODE}...`);

    const response = await got(`http://animeheaven.eu/watch.php?${QUERY}`);
    const body = response.body;

    let STREAM_REGEX_DATA = STREAM_1_REGEX.exec(body);
    if (STREAM_REGEX_DATA) {
        let encoded = STREAM_REGEX_DATA[1].decodeEscapeSequence();
        encoded = encoded.replace(/\|/g, "0");
        const encrypted = base64Decode(encoded);
        streams.stream_1 = decrypt(ENCRYPTION_KEY, encrypted);
    }

    STREAM_REGEX_DATA = STREAM_2_REGEX.exec(body);
    if (STREAM_REGEX_DATA) {
        let encoded = STREAM_REGEX_DATA[1].decodeEscapeSequence();
        encoded = encoded.replace(/\|/g, "0");
        const encrypted = base64Decode(encoded);
        streams.stream_2 = decrypt(ENCRYPTION_KEY, encrypted);
    }

    STREAM_REGEX_DATA = STREAM_3_REGEX.exec(body);
    if (STREAM_REGEX_DATA) {
        let encoded = STREAM_REGEX_DATA[1].decodeEscapeSequence();
        encoded = encoded.replace(/\|/g, "0");
        const encrypted = base64Decode(encoded);
        streams.stream_3 = decrypt(ENCRYPTION_KEY, encrypted);
    }

    console.log(streams);
})();

function base64Decode(base64) {
    return Buffer.from(base64, 'base64').toString('binary');
}

function decrypt(key, crypted) {
    const unknown_3 = [];
    let j = 0;
    let unknown_1;
    let unknown_2 = '';

    for (let i = 0; i < 256; i++) {
        unknown_3[i] = i;
    }
    for (i = 0; i < 256; i++) {
        j = (j + unknown_3[i] + key.charCodeAt(i % key.length)) % 256;
        unknown_1 = unknown_3[i];
        unknown_3[i] = unknown_3[j];
        unknown_3[j] = unknown_1;
    }

    i = 0;
    j = 0;

    for (let k = 0; k < crypted.length; k++) {
        i = (i + 1) % 256;
        j = (j + unknown_3[i]) % 256;
        unknown_1 = unknown_3[i];
        unknown_3[i] = unknown_3[j];
        unknown_3[j] = unknown_1;
        unknown_2 += String.fromCharCode(crypted.charCodeAt(k) ^ unknown_3[(unknown_3[i] + unknown_3[j]) % 256]);
    }

    return unknown_2;
}