求问这段js代码有什么用的
(function() {var e = window,
f = "push",
k = "length",
l = "prototype",
q = function(a) {
if (a.get && a.set) {
this.clear();
var d = a.get("buildHitTask");
a.set("buildHitTask", n(this, d));
a.set("_rlt", p(this, a.get("_rlt")))
}
},
r = {
action: "pa",
promoAction: "promoa",
id: "ti",
affiliation: "ta",
revenue: "tr",
tax: "tt",
shipping: "ts",
coupon: "tcc",
step: "cos",
label: "col",
option: "col",
options: "col",
list: "pal",
listSource: "pls"
},
t = {
id: "id",
name: "nm",
brand: "br",
category: "ca",
variant: "va",
position: "ps",
price: "pr",
quantity: "qt",
coupon: "cc",
"dimension(\\d+)": "cd",
"metric(\\d+)": "cm"
},
u = {
id: "id",
name: "nm",
creative: "cr",
position: "ps"
},
v = function(a, d) {
this.name = a;
this.source = d;
this.e = []
},
w = "detail checkout checkout_option click add remove purchase refund".split(" ");
q[l].clear = function() {
this.b = void 0;
this.f = [];
this.a = [];
this.g = [];
this.d = void 0
};
q[l].h = function(a, d) {
var b = d || {};
"promo_click" == a ? b.promoAction = "click": b.action = a;
this.b = x(b)
};
q[l].j = function(a) { (a = x(a)) && this.f[f](a)
};
q[l].i = function(a) {
var d = x(a);
if (d) {
var b, c = a.list || "";
a = a.listSource || "";
for (var g = 0; g < this.a[k]; g++) if (this.a[g].name == c) {
b = this.a[g];
break
}
b || (b = new v(c, a), this.a[f](b));
b.e[f](d)
}
};
q[l].c = function(a) { (a = x(a)) && this.g[f](a)
};
var y = function(a, d, b) {
if ("[object Array]" == Object[l].toString.call(Object(a))) for (var c = 0; c < a[k]; c++) d.call(b, a[c])
};
q[l].data = function(a) {
if (a && a.ecommerce) {
a = a.ecommerce;
a.promoView && y(a.promoView.promotions, this.c, this);
a.promoClick && (this.h("promo_click", a.promoClick.actionField), y(a.promoClick.promotions, this.c, this));
for (var d = 0; d < w[k]; d++) {
var b = a[w[d]];
if (b) {
this.h(w[d], b.actionField);
y(b.products, this.j, this);
break
}
}
y(a.impressions, this.i, this);
a.currencyCode && (this.d = a.currencyCode)
}
};
var n = function(a, d) {
return function(b) {
var c, g, h;
a.b && z(r, a.b, b, "&");
for (c = 0; c < a.f[k]; c++) g = "&pr" + (c + 1),
z(t, a.f[c], b, g);
for (c = 0; c < a.a[k]; c++) {
h = a.a[c];
g = "&il" + (c + 1);
h.name && b.set(g + "nm", h.name, !0);
h.source && b.set(g + "ls", h.source, !0);
for (var m = 0; m < h.e[k]; m++) z(t, h.e[m], b, g + "pi" + (m + 1))
}
for (c = 0; c < a.g[k]; c++) g = "&promo" + (c + 1),
z(u, a.g[c], b, g);
a.d && b.set("&cu", a.d, !0);
a.clear();
return d(b)
}
},
p = function(a, d) {
return function(b) {
var c = a.b && a.b.action;
if ("purchase" != c && "refund" != c) return d(b)
}
},
x = function(a) {
var d = 0,
b = {};
if (a && "object" == typeof a) for (var c in a) a.hasOwnProperty(c) && (b[c] = a[c], d++);
return d ? b: void 0
},
z = function(a, d, b, c) {
for (var g in d) if (d.hasOwnProperty(g)) for (var h in a) if (a.hasOwnProperty(h)) {
var m = g.match("^" + h + "$");
m && b.set(c + a[h] + m.slice(1).join(""), d[g], !0)
}
}; (function() {
e.gaplugins = e.gaplugins || {};
e.gaplugins.EC = q;
q[l].setAction = q[l].h;
q[l].addProduct = q[l].j;
q[l].addImpression = q[l].i;
q[l].addPromo = q[l].c;
q[l].clear = q[l].clear;
q[l].data = q[l].data;
var a = e.GoogleAnalyticsObject || "ga";
e[a] = e[a] ||
function() { (e[a].q = e[a].q || [])[f](arguments)
};
e[a]("provide", "ec", q)
})();
})();
