clientside templating

www/common/LessLoader.js

@@ -0,0 +1,64 @@
+/*@flow*/
+/*:: const define = () => {}; */
+define([
+    '/api/config',
+    '/bower_components/less/dist/less.js'
+], function (Config, Less) { /*::});module.exports = (function() {
+    const Config = (undefined:any);
+    const Less = (undefined:any);
+    */
+
+    var module = { exports: {} };
+    var key = Config.requireConf.urlArgs;
+    var localStorage = window.localStorage || {};
+
+    var fixURL = function (url) {
+        var mark = (url.indexOf('?') !== -1) ? '&' : '?';
+        return url + mark + key;
+    };
+
+    var doXHR = Less.FileManager.prototype.doXHR;
+    Less.FileManager.prototype.doXHR = function (url, type, callback, errback) {
+        url = fixURL(url);
+        //console.log("xhr: " + url);
+        return doXHR(url, type, callback, errback);
+    };
+
+    var inject = function (cssText, url) {
+        var curStyle = document.createElement('style');
+        curStyle.setAttribute('data-original-src', url);
+        curStyle.type = 'text/css';
+        curStyle.appendChild(document.createTextNode(cssText));
+        if (!document.head) { throw new Error(); }
+        document.head.appendChild(curStyle);
+    };
+
+    var checkCache = function () {
+        if (localStorage['LESS_CACHE'] === key) { return; }
+        Object.keys(localStorage).forEach(function (k) {
+            if (k.indexOf('LESS_CACHE|') !== 0) { return; }
+            delete localStorage[k];
+        });
+        localStorage['LESS_CACHE'] = key;
+    };
+
+    var load = module.exports.load = function (url /*:string*/, cb /*:()=>void*/) {
+        checkCache();
+        if (localStorage['LESS_CACHE|' + key + '|' + url]) {
+            inject(localStorage['LESS_CACHE|' + key + '|' + url], url);
+            cb();
+            return;
+        }
+        Less.render('@import (multiple) "' + url + '";', {}, function(err, css) {
+            if (err) {
+                console.log(err);
+                return;
+            }
+            localStorage['LESS_CACHE|' + key + '|' + url] = css.css;
+            inject(css.css, url);
+            cb();
+        }, window.less);
+    };
+
+    return module.exports;
+})/*::()*/;