Smart File Size Filter for VueJS

smart-file-size-filter.js

var Vue = require('vue');

var UNITS = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
var STEP = 1024;

function format(value, power) {
    return (value / Math.pow(STEP, power)).toFixed(2) + UNITS[power];
}

Vue.filter('smart-file-size', {
    read: function (value) {
        value = parseFloat(value, 10);
        for (var i = 0; i < UNITS.length; i++) {
            if (value < Math.pow(STEP, i)) {
                if (UNITS[i - 1]) {
                    return format(value, i - 1);
                }
                return value + UNITS[i];
            }
        }
        return format(value, i - 1);
    },
    write: function (value, oldValue) {
        var exp = new RegExp('^(\\d+(?:\\.\\d+)?)(' + UNITS.join('|') +')$', 'i');
        var ret = value.match(exp);
        if (ret) {
            var i = UNITS.indexOf(ret[2].toUpperCase());
            if (i >= 0) {
                return parseFloat(ret[1], 10) * Math.pow(STEP, i);
            }
        }
        return oldValue;
    }
});

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