leptos/examples/islands_router/public/routing.js

136 lines
4.7 KiB
JavaScript

window.addEventListener("click", async (ev) => {
// confirm that this is an <a> that meets our requirements
if (
ev.defaultPrevented ||
ev.button !== 0 ||
ev.metaKey ||
ev.altKey ||
ev.ctrlKey ||
ev.shiftKey
)
return;
/** @type HTMLAnchorElement | undefined;*/
const a = ev
.composedPath()
.find(el => el instanceof Node && el.nodeName.toUpperCase() === "A");
if (!a) return;
const svg = a.namespaceURI === "http://www.w3.org/2000/svg";
const href = svg ? a.href.baseVal : a.href;
const target = svg ? a.target.baseVal : a.target;
if (target || (!href && !a.hasAttribute("state"))) return;
const rel = (a.getAttribute("rel") || "").split(/\s+/);
if (a.hasAttribute("download") || (rel && rel.includes("external"))) return;
const url = svg ? new URL(href, document.baseURI) : new URL(href);
if (
url.origin !== window.location.origin // ||
// TODO base
//(basePath && url.pathname && !url.pathname.toLowerCase().startsWith(basePath.toLowerCase()))
)
return;
ev.preventDefault();
// fetch the new page
const resp = await fetch(url);
const htmlString = await resp.text();
// Use DOMParser to parse the HTML string
const parser = new DOMParser();
// TODO parse from the request stream instead?
const doc = parser.parseFromString(htmlString, 'text/html');
// The 'doc' variable now contains the parsed DOM
const transition = document.startViewTransition(async () => {
const oldDocWalker = document.createTreeWalker(document);
const newDocWalker = doc.createTreeWalker(doc);
let oldNode = oldDocWalker.currentNode;
let newNode = newDocWalker.currentNode;
while(oldDocWalker.nextNode() && newDocWalker.nextNode()) {
oldNode = oldDocWalker.currentNode;
newNode = newDocWalker.currentNode;
// if the nodes are different, we need to replace the old with the new
// because of the typed view tree, this should never actually happen
if (oldNode.nodeType !== newNode.nodeType) {
oldNode.replaceWith(newNode);
}
// if it's a text node, just update the text with the new text
else if (oldNode.nodeType === Node.TEXT_NODE) {
oldNode.textContent = newNode.textContent;
}
// if it's an element, replace if it's a different tag, or update attributes
else if (oldNode.nodeType === Node.ELEMENT_NODE) {
/** @type Element */
const oldEl = oldNode;
/** @type Element */
const newEl = newNode;
if (oldEl.tagName !== newEl.tagName) {
oldEl.replaceWith(newEl);
}
else {
for(const attr of newEl.attributes) {
oldEl.setAttribute(attr.name, attr.value);
}
}
}
// we use comment "branch marker" nodes to distinguish between different branches in the statically-typed view tree
// if one of these marker is hit, then there are two options
// 1) it's the same branch, and we just keep walking until the end
// 2) it's a different branch, in which case the old can be replaced with the new wholesale
else if (oldNode.nodeType === Node.COMMENT_NODE) {
const oldText = oldNode.textContent;
const newText = newNode.textContent;
if(oldText.startsWith("bo") && newText !== oldText) {
oldDocWalker.nextNode();
newDocWalker.nextNode();
const oldRange = new Range();
const newRange = new Range();
let oldBranches = 1;
let newBranches = 1;
while(oldBranches > 0 && newBranches > 0) {
if(oldDocWalker.nextNode() && newDocWalker.nextNode()) {
console.log(oldDocWalker.currentNode, newDocWalker.currentNode);
if(oldDocWalker.currentNode.nodeType === Node.COMMENT_NODE) {
if(oldDocWalker.currentNode.textContent.startsWith("bo")) {
oldBranches += 1;
} else if(oldDocWalker.currentNode.textContent.startsWith("bc")) {
oldBranches -= 1;
}
}
if(newDocWalker.currentNode.nodeType === Node.COMMENT_NODE) {
if(newDocWalker.currentNode.textContent.startsWith("bo")) {
newBranches += 1;
} else if(newDocWalker.currentNode.textContent.startsWith("bc")) {
newBranches -= 1;
}
}
}
}
try {
oldRange.setStartAfter(oldNode);
oldRange.setEndBefore(oldDocWalker.currentNode);
newRange.setStartAfter(newNode);
newRange.setEndBefore(newDocWalker.currentNode);
const newContents = newRange.extractContents();
oldRange.deleteContents();
oldRange.insertNode(newContents);
oldNode.replaceWith(newNode);
oldDocWalker.currentNode.replaceWith(newDocWalker.currentNode);
} catch (e) {
console.error(e);
}
} }
}
});
await transition;
window.history.pushState(undefined, null, url);
});