Challenge: API Key Security

(function() {
    function c() {}
    var l = null,
        g = cc.prototype;
    g.Ya = function(c) {
        this.aa = c;
        this.b = c.b
    };
    g.Ya.prototype.Z = function() {};
    g.Ga = function(c) {
        this.type = c;
        this.b = c.b
    };
    var n = g.Ga.prototype;
    n.Z = function() {};
    n.Zd = function() {};
    g.e = new function() {};
    g.Qa = new function() {};
    c.prototype.jm = function(c, b, a, g) {
        b = t.encode(b);
        for (var l = 0, l = 0; l < a; l++) b = b.charAt(Math.floor(Math.random() * (b.length - 1))) + b;
        for (l = 0; l < g; l++) b += b.charAt(Math.floor(Math.random() * (b.length - 1)));
        c.ca(b)
    };
    c.prototype.fm = function(c, b) {
        null === l &&
            (l = new SHA1);
        c.ca(l.hash(b))
    };
    g.ga = new c;
    var t = {
        vc: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
        encode: function(c) {
            var b = "",
                a, g, l, d, e, k, f = 0;
            for (c = t.lm(c); f < c.length;) a = c.charCodeAt(f++), g = c.charCodeAt(f++), l = c.charCodeAt(f++), d = a >> 2, a = (a & 3) << 4 | g >> 4, e = (g & 15) << 2 | l >> 6, k = l & 63, isNaN(g) ? e = k = 64 : isNaN(l) && (k = 64), b = b + this.vc.charAt(d) + this.vc.charAt(a) + this.vc.charAt(e) + this.vc.charAt(k);
            return b
        },
        decode: function(c) {
            var b = "",
                a, g, l, d, e, k = 0;
            for (c = c.replace(/[^A-Za-z0-9\+\/\=]/g, ""); k <
                c.length;) a = this.vc.indexOf(c.charAt(k++)), g = this.vc.indexOf(c.charAt(k++)), d = this.vc.indexOf(c.charAt(k++)), e = this.vc.indexOf(c.charAt(k++)), a = a << 2 | g >> 4, g = (g & 15) << 4 | d >> 2, l = (d & 3) << 6 | e, b += String.fromCharCode(a), 64 != d && (b += String.fromCharCode(g)), 64 != e && (b += String.fromCharCode(l));
            return b = t.km(b)
        },
        lm: function(c) {
            c = c.replace(/\r\n/g, "\n");
            for (var b = "", a = 0; a < c.length; a++) {
                var g = c.charCodeAt(a);
                128 > g ? b += String.fromCharCode(g) : (127 < g && 2048 > g ? b += String.fromCharCode(g >> 6 | 192) : (b += String.fromCharCode(g >>
                    12 | 224), b += String.fromCharCode(g >> 6 & 63 | 128)), b += String.fromCharCode(g & 63 | 128))
            }
            return b
        },
        km: function(c) {
            for (var b = "", a = 0, g = 0, l = 0, d = 0; a < c.length;) g = c.charCodeAt(a), 128 > g ? (b += String.fromCharCode(g), a++) : 191 < g && 224 > g ? (l = c.charCodeAt(a + 1), b += String.fromCharCode((g & 31) << 6 | l & 63), a += 2) : (l = c.charCodeAt(a + 1), d = c.charCodeAt(a + 2), b += String.fromCharCode((g & 15) << 12 | (l & 63) << 6 | d & 63), a += 3);
            return b
        }
    }
})();
[/code:cfu0wb6o]

The basic encoding scheme seems to be looping through the initial input length and choosing pseudorandom characters from this set:
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=

I pulled the encode function straight out of the JS, but the length varies and I am not versed enough in JS (or really I don't have the right tools in hand) to trace the input variables back to the HTML.

The key function to trace back out is:
[code:cfu0wb6o]c.prototype.jm = function(c, b, a, g)[/code:cfu0wb6o]
and tracing c, b, a and g back out to the HTML inputs, from there you can just fabricate inputs and retrace the steps back down to the encode function.