stylus/apply.js
2015-03-04 14:03:29 -06:00

116 lines
3.7 KiB
JavaScript

chrome.extension.sendMessage({method: "getStyles", matchUrl: location.href, enabled: true, asHash: true}, applyStyles);
chrome.extension.onMessage.addListener(function(request, sender, sendResponse) {
switch (request.method) {
case "styleDeleted":
removeStyle(request.id, document);
break;
case "styleUpdated":
removeStyle(request.style.id, document);
//fallthrough
case "styleAdded":
if (request.style.enabled == "true") {
chrome.extension.sendMessage({method: "getStyles", matchUrl: location.href, enabled: true, id: request.style.id, asHash: true}, applyStyles);
}
break;
case "styleApply":
for (var styleId in request.styles) {
applySections(styleId, request.styles[styleId]);
}
break;
case "styleReplaceAll":
replaceAll(request.styles);
break;
}
});
function removeStyle(id, doc) {
var e = doc.getElementById("stylish-" + id);
if (e) {
e.parentNode.removeChild(e);
}
getDynamicIFrames(doc).forEach(function(iframe) {
removeStyle(id, iframe.contentDocument);
});
}
function applyStyles(styleHash) {
for (var styleId in styleHash) {
applySections(styleId, styleHash[styleId]);
}
}
function applySections(styleId, sections) {
var styleElement = document.getElementById("stylish-" + styleId);
// Already there.
if (styleElement) {
return;
}
if (document.documentElement instanceof SVGSVGElement) {
// SVG document, make an SVG style element.
styleElement = document.createElementNS("http://www.w3.org/2000/svg", "style");
} else {
// This will make an HTML style element. If there's SVG embedded in an HTML document, this works on the SVG too.
styleElement = document.createElement("style");
}
styleElement.setAttribute("id", "stylish-" + styleId);
styleElement.setAttribute("class", "stylish");
styleElement.setAttribute("type", "text/css");
styleElement.appendChild(document.createTextNode(sections.map(function(section) {
return section.code;
}).join("\n")));
addStyleElement(styleElement, document);
}
function addStyleElement(styleElement, doc) {
doc.documentElement.appendChild(doc.importNode(styleElement, true));
getDynamicIFrames(doc).forEach(function(iframe) {
addStyleElement(styleElement, iframe.contentDocument);
});
}
// Only dynamic iframes get the parent document's styles. Other ones should get styles based on their own URLs.
function getDynamicIFrames(doc) {
return Array.prototype.filter.call(doc.getElementsByTagName('iframe'), iframeIsDynamic);
}
function iframeIsDynamic(f) {
var href;
try {
href = f.contentDocument.location.href;
} catch (ex) {
// Cross-origin, so it's not a dynamic iframe
return false;
}
return href == document.location.href || href.indexOf("about:") == 0;
}
function replaceAll(newStyles, doc) {
Array.prototype.forEach.call(doc.querySelectorAll("STYLE.stylish"), function(style) {
style.parentNode.removeChild(style);
});
applyStyles(newStyles);
getDynamicIFrames(doc).forEach(function(iframe) {
replaceAll(newStyles, iframe.contentDocument);
});
}
// Observe dynamic IFRAMEs being added
var iframeObserver = new MutationObserver(function(mutations) {
var styles = Array.prototype.slice.call(document.querySelectorAll('STYLE.stylish'));
if (styles.length == 0) {
return;
}
mutations.filter(function(mutation) {
return "childList" === mutation.type;
}).forEach(function(mutation) {
Array.prototype.filter.call(mutation.addedNodes, function(node) { return "IFRAME" === node.tagName; }).filter(iframeIsDynamic).forEach(function(iframe) {
var doc = iframe.contentDocument;
styles.forEach(function(style) {
doc.documentElement.appendChild(doc.importNode(style, true));
});
});
});
});
iframeObserver.observe(document, {childList: true, subtree: true});