lepu-test-platform-web/node_modules/postcss-zindex/lib/layerCache.js

49 lines
1.1 KiB
JavaScript

'use strict';
var has = require('has');
var uniq = require('uniqs');
function LayerCache (opts) {
if (!(this instanceof LayerCache)) {
return new LayerCache(opts);
}
this._values = [];
this._startIndex = opts.startIndex || 1;
}
function ascending (a, b) {
return a - b;
}
function reduceValues (list, value, index) {
list[value] = index + this._startIndex;
return list;
}
LayerCache.prototype._findValue = function (value) {
if (has(this._values, value)) {
return this._values[value];
}
return false;
};
LayerCache.prototype.optimizeValues = function () {
this._values = uniq(this._values).sort(ascending).reduce(reduceValues.bind(this), {});
};
LayerCache.prototype.addValue = function (value) {
var parsedValue = parseInt(value, 10);
// pass only valid values
if (!parsedValue || parsedValue < 0) {
return;
}
this._values.push(parsedValue);
};
LayerCache.prototype.getValue = function (value) {
var parsedValue = parseInt(value, 10);
return this._findValue(parsedValue) || value;
};
module.exports = LayerCache;