rand.js

function randomize(seed) {
    var KK = 100;
    var LL = 37;

    var mod_sum = function (x, y) {
        return x + y - (x + y | 0);
    };

    var ran_u = Array(KK);

    var ranf_array = function (aa, n) {
        var i, j;
        for (j = 0; j < KK; j++)
            aa[j] = ran_u[j];
        for (; j < n; j++)
            aa[j] = aa[j - KK] + aa[j - LL] - (aa[j - KK] + aa[j - LL] | 0);
        for (i = 0; i < LL; i++, j++)
            ran_u[i] = aa[j - KK] + aa[j - LL] - (aa[j - KK] + aa[j - LL] | 0);
        for (; i < KK; i++, j++)
            ran_u[i] = aa[j - KK] + ran_u[i - LL] - (aa[j - KK] + ran_u[i - LL] | 0);
    };

    var ranf_start = function (seed) {
        var t, s, j;
        var u = Array(KK + KK - 1);
        var ulp = (1.0 / (1 << 30)) / (1 << 22); /* 2 to the -52 */
        var ss = 2.0 * ulp * ((seed & 0x3fffffff) + 2);
        var TT = 70; /* guaranteed separation between streams */

        function is_odd(s) {
            return ((s) & 1);
        }

        for (j = 0; j < KK; j++) {
            u[j] = ss; /* bootstrap the buffer */
            ss += ss;
            if (ss >= 1.0) ss -= 1.0 - 2 * ulp; /* cyclic shift of 51 bits */
        }
        u[1] += ulp; /* make u[1] (and only u[1]) "odd" */
        for (s = seed & 0x3fffffff, t = TT - 1; t;) {
            for (j = KK - 1; j > 0; j--)
                u[j + j] = u[j], u[j + j - 1] = 0.0; /* "square" */
            for (j = KK + KK - 2; j >= KK; j--) {
                u[j - (KK - LL)] = mod_sum(u[j - (KK - LL)], u[j]);
                u[j - KK] = mod_sum(u[j - KK], u[j]);
            }
            if (is_odd(s)) { /* "multiply by z" */
                for (j = KK; j > 0; j--) u[j] = u[j - 1];
                u[0] = u[KK]; /* shift the buffer cyclically */
                u[LL] = mod_sum(u[LL], u[KK]);
            }
            if (s) s >>= 1;
            else t--;
        }
        for (j = 0; j < LL; j++) ran_u[j + KK - LL] = u[j];
        for (; j < KK; j++) ran_u[j - LL] = u[j];
        for (j = 0; j < 10; j++) ranf_array(u, KK + KK - 1); /* warm things up */
    };


    function getHashCode(s) {
        var hash = 0;
        if (s.length == 0) return hash;
        for (i = 0; i < s.length; i++) {
            char = s.charCodeAt(i);
            hash = ((hash << 5) - hash) + char;
            hash = hash & hash; // Convert to 32bit integer
        }
        return hash;
    }

    /* Usage */
    var a = Array(1009),
        i = 0;
    ranf_start(getHashCode(seed.toLowerCase()));
    ranf_array(a, 1009);
    window.random = function () {
        1009 === i && (seed = a[i - 1], i = 0, ranf_start(seed), ranf_array(a, 1009));
        return a[i++];
    };
};

randomize("1236");

function shuffle(array) {
    var counter = array.length,
        temp, index;

    // While there are elements in the array
    while (counter--) {
        // Pick a random index
        index = (random() * counter) | 0;

        // And swap the last element with it
        temp = array[counter];
        array[counter] = array[index];
        array[index] = temp;
    }

    return array;
}