d2-ui
Version:
247 lines (218 loc) • 7.15 kB
JavaScript
/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
var stylesInDom = {},
memoize = function(fn) {
var memo;
return function () {
if (typeof memo === "undefined") memo = fn.apply(this, arguments);
return memo;
};
},
isOldIE = memoize(function() {
return /msie [6-9]\b/.test(window.navigator.userAgent.toLowerCase());
}),
getHeadElement = memoize(function () {
return document.head || document.getElementsByTagName("head")[0];
}),
singletonElement = null,
singletonCounter = 0,
styleElementsInsertedAtTop = [];
module.exports = function(list, options) {
if(typeof DEBUG !== "undefined" && DEBUG) {
if(typeof document !== "object") throw new Error("The style-loader cannot be used in a non-browser environment");
}
options = options || {};
// Force single-tag solution on IE6-9, which has a hard limit on the # of <style>
// tags it will allow on a page
if (typeof options.singleton === "undefined") options.singleton = isOldIE();
// By default, add <style> tags to the bottom of <head>.
if (typeof options.insertAt === "undefined") options.insertAt = "bottom";
var styles = listToStyles(list);
addStylesToDom(styles, options);
return function update(newList) {
var mayRemove = [];
for(var i = 0; i < styles.length; i++) {
var item = styles[i];
var domStyle = stylesInDom[item.id];
domStyle.refs--;
mayRemove.push(domStyle);
}
if(newList) {
var newStyles = listToStyles(newList);
addStylesToDom(newStyles, options);
}
for(var i = 0; i < mayRemove.length; i++) {
var domStyle = mayRemove[i];
if(domStyle.refs === 0) {
for(var j = 0; j < domStyle.parts.length; j++)
domStyle.parts[j]();
delete stylesInDom[domStyle.id];
}
}
};
}
function addStylesToDom(styles, options) {
for(var i = 0; i < styles.length; i++) {
var item = styles[i];
var domStyle = stylesInDom[item.id];
if(domStyle) {
domStyle.refs++;
for(var j = 0; j < domStyle.parts.length; j++) {
domStyle.parts[j](item.parts[j]);
}
for(; j < item.parts.length; j++) {
domStyle.parts.push(addStyle(item.parts[j], options));
}
} else {
var parts = [];
for(var j = 0; j < item.parts.length; j++) {
parts.push(addStyle(item.parts[j], options));
}
stylesInDom[item.id] = {id: item.id, refs: 1, parts: parts};
}
}
}
function listToStyles(list) {
var styles = [];
var newStyles = {};
for(var i = 0; i < list.length; i++) {
var item = list[i];
var id = item[0];
var css = item[1];
var media = item[2];
var sourceMap = item[3];
var part = {css: css, media: media, sourceMap: sourceMap};
if(!newStyles[id])
styles.push(newStyles[id] = {id: id, parts: [part]});
else
newStyles[id].parts.push(part);
}
return styles;
}
function insertStyleElement(options, styleElement) {
var head = getHeadElement();
var lastStyleElementInsertedAtTop = styleElementsInsertedAtTop[styleElementsInsertedAtTop.length - 1];
if (options.insertAt === "top") {
if(!lastStyleElementInsertedAtTop) {
head.insertBefore(styleElement, head.firstChild);
} else if(lastStyleElementInsertedAtTop.nextSibling) {
head.insertBefore(styleElement, lastStyleElementInsertedAtTop.nextSibling);
} else {
head.appendChild(styleElement);
}
styleElementsInsertedAtTop.push(styleElement);
} else if (options.insertAt === "bottom") {
head.appendChild(styleElement);
} else {
throw new Error("Invalid value for parameter 'insertAt'. Must be 'top' or 'bottom'.");
}
}
function removeStyleElement(styleElement) {
styleElement.parentNode.removeChild(styleElement);
var idx = styleElementsInsertedAtTop.indexOf(styleElement);
if(idx >= 0) {
styleElementsInsertedAtTop.splice(idx, 1);
}
}
function createStyleElement(options) {
var styleElement = document.createElement("style");
styleElement.type = "text/css";
insertStyleElement(options, styleElement);
return styleElement;
}
function createLinkElement(options) {
var linkElement = document.createElement("link");
linkElement.rel = "stylesheet";
insertStyleElement(options, linkElement);
return linkElement;
}
function addStyle(obj, options) {
var styleElement, update, remove;
if (options.singleton) {
var styleIndex = singletonCounter++;
styleElement = singletonElement || (singletonElement = createStyleElement(options));
update = applyToSingletonTag.bind(null, styleElement, styleIndex, false);
remove = applyToSingletonTag.bind(null, styleElement, styleIndex, true);
} else if(obj.sourceMap &&
typeof URL === "function" &&
typeof URL.createObjectURL === "function" &&
typeof URL.revokeObjectURL === "function" &&
typeof Blob === "function" &&
typeof btoa === "function") {
styleElement = createLinkElement(options);
update = updateLink.bind(null, styleElement);
remove = function() {
removeStyleElement(styleElement);
if(styleElement.href)
URL.revokeObjectURL(styleElement.href);
};
} else {
styleElement = createStyleElement(options);
update = applyToTag.bind(null, styleElement);
remove = function() {
removeStyleElement(styleElement);
};
}
update(obj);
return function updateStyle(newObj) {
if(newObj) {
if(newObj.css === obj.css && newObj.media === obj.media && newObj.sourceMap === obj.sourceMap)
return;
update(obj = newObj);
} else {
remove();
}
};
}
var replaceText = (function () {
var textStore = [];
return function (index, replacement) {
textStore[index] = replacement;
return textStore.filter(Boolean).join('\n');
};
})();
function applyToSingletonTag(styleElement, index, remove, obj) {
var css = remove ? "" : obj.css;
if (styleElement.styleSheet) {
styleElement.styleSheet.cssText = replaceText(index, css);
} else {
var cssNode = document.createTextNode(css);
var childNodes = styleElement.childNodes;
if (childNodes[index]) styleElement.removeChild(childNodes[index]);
if (childNodes.length) {
styleElement.insertBefore(cssNode, childNodes[index]);
} else {
styleElement.appendChild(cssNode);
}
}
}
function applyToTag(styleElement, obj) {
var css = obj.css;
var media = obj.media;
if(media) {
styleElement.setAttribute("media", media)
}
if(styleElement.styleSheet) {
styleElement.styleSheet.cssText = css;
} else {
while(styleElement.firstChild) {
styleElement.removeChild(styleElement.firstChild);
}
styleElement.appendChild(document.createTextNode(css));
}
}
function updateLink(linkElement, obj) {
var css = obj.css;
var sourceMap = obj.sourceMap;
if(sourceMap) {
// http://stackoverflow.com/a/26603875
css += "\n/*# sourceMappingURL=data:application/json;base64," + btoa(unescape(encodeURIComponent(JSON.stringify(sourceMap)))) + " */";
}
var blob = new Blob([css], { type: "text/css" });
var oldSrc = linkElement.href;
linkElement.href = URL.createObjectURL(blob);
if(oldSrc)
URL.revokeObjectURL(oldSrc);
}