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// Cache system is a bit outdated and could do with work
export default (window, options, logger) => {
let cache = null;
if (options.env !== 'development') {
try {
cache = (typeof window.localStorage === 'undefined') ? null : window.localStorage;
} catch (_) {}
}
return {
setCSS: function(path, lastModified, modifyVars, styles) {
if (cache) {
logger.info(`saving ${path} to cache.`);
try {
cache.setItem(path, styles);
cache.setItem(`${path}:timestamp`, lastModified);
if (modifyVars) {
cache.setItem(`${path}:vars`, JSON.stringify(modifyVars));
}
} catch (e) {
// TODO - could do with adding more robust error handling
logger.error(`failed to save "${path}" to local storage for caching.`);
}
}
},
getCSS: function(path, webInfo, modifyVars) {
const css = cache && cache.getItem(path);
const timestamp = cache && cache.getItem(`${path}:timestamp`);
let vars = cache && cache.getItem(`${path}:vars`);
modifyVars = modifyVars || {};
vars = vars || "{}"; // if not set, treat as the JSON representation of an empty object
if (timestamp && webInfo.lastModified &&
(new Date(webInfo.lastModified).valueOf() ===
new Date(timestamp).valueOf()) &&
JSON.stringify(modifyVars) === vars) {
// Use local copy
return css;
}
}
};
};