31 lines
853 B
JavaScript
31 lines
853 B
JavaScript
var meta = require('./meta');
|
|
var clamp = require('./clamp');
|
|
var trim = require('./trim');
|
|
var each = require('./each');
|
|
var map = require('./map');
|
|
var isNaN = require('./isNaN');
|
|
exports = function() {
|
|
var viewport = meta('viewport');
|
|
if (!viewport) return 1;
|
|
viewport = map(viewport.split(','), function(val) {
|
|
return trim(val);
|
|
});
|
|
var minScale = 0.25,
|
|
maxScale = 5,
|
|
initialScale = 1;
|
|
each(viewport, function(val) {
|
|
val = val.split('=');
|
|
var key = val[0];
|
|
val = val[1];
|
|
if (key === 'initial-scale') initialScale = +val;
|
|
if (key === 'maximum-scale') maxScale = +val;
|
|
if (key === 'minimum-scale') minScale = +val;
|
|
});
|
|
var ret = clamp(initialScale, minScale, maxScale);
|
|
|
|
if (isNaN(ret)) return 1;
|
|
return ret;
|
|
};
|
|
|
|
module.exports = exports;
|