From 3a29f4c86ee7ed13fb8683b2728a856581e32de7 Mon Sep 17 00:00:00 2001
From: Jacky Zhao <j.zhao2k19@gmail.com>
Date: Fri, 9 Jun 2023 19:58:58 -0700
Subject: [PATCH] add custom spa solution

---
 quartz/bootstrap-cli.mjs                |   4 +
 quartz/components/Head.tsx              |   6 +-
 quartz/components/scripts/spa.inline.ts | 133 +++++++++++++++++++++++-
 quartz/plugins/index.ts                 |   1 +
 4 files changed, 138 insertions(+), 6 deletions(-)
diff --git a/quartz/bootstrap-cli.mjs b/quartz/bootstrap-cli.mjs
index e9cda4e09..e6bb3f0a8 100755
--- a/quartz/bootstrap-cli.mjs
+++ b/quartz/bootstrap-cli.mjs
@@ -71,6 +71,10 @@ yargs(hideBin(process.argv))
           setup(build) {
             build.onLoad({ filter: /\.inline\.(ts|js)$/ }, async (args) => {
               let text = await promises.readFile(args.path, 'utf8')
+              // remove default exports that we manually inserted
+              text = text.replace('export default', '')
+              text = text.replace('export', '')
+
               const transpiled = await esbuild.build({
                 stdin: {
                   contents: text,
diff --git a/quartz/components/Head.tsx b/quartz/components/Head.tsx
index c56b8cbc0..37c0abaae 100644
--- a/quartz/components/Head.tsx
+++ b/quartz/components/Head.tsx
@@ -9,7 +9,7 @@ export default function Head({ fileData, externalResources }: QuartzComponentPro
   const baseDir = resolveToRoot(slug)
   const iconPath = baseDir + "/static/icon.png"
   const ogImagePath = baseDir + "/static/og-image.png"
-
+  
   return <head>
     <title>{title}</title>
     <meta charSet="utf-8" />
@@ -24,7 +24,7 @@ export default function Head({ fileData, externalResources }: QuartzComponentPro
     <meta name="generator" content="Quartz" />
     <link rel="preconnect" href="https://fonts.googleapis.com" />
     <link rel="preconnect" href="https://fonts.gstatic.com" />
-    {css.map(href => <link key={href} href={href} rel="stylesheet" type="text/css" />)}
-    {js.filter(resource => resource.loadTime === "beforeDOMReady").map(resource => <script key={resource.src} {...resource} />)}
+    {css.map(href => <link key={href} href={href} rel="stylesheet" type="text/css" spa-preserve />)}
+    {js.filter(resource => resource.loadTime === "beforeDOMReady").map(resource => <script key={resource.src} {...resource} spa-preserve />)}
   </head>
 }
diff --git a/quartz/components/scripts/spa.inline.ts b/quartz/components/scripts/spa.inline.ts
index 4020c2305..2063a15c7 100644
--- a/quartz/components/scripts/spa.inline.ts
+++ b/quartz/components/scripts/spa.inline.ts
@@ -1,3 +1,130 @@
-import flamethrower from 'flamethrower-router'
-const router = flamethrower()
-export default "SpaScript"
+import micromorph from "micromorph"
+
+// adapted from `micromorph`
+// https://github.com/natemoo-re/micromorph
+
+const NODE_TYPE_ELEMENT = 1
+let announcer = document.createElement('route-announcer')
+const isElement = (target: EventTarget | null): target is Element => (target as Node)?.nodeType === NODE_TYPE_ELEMENT
+const isLocalUrl = (href: string) => {
+  try {
+    const url = new URL(href)
+    if (window.location.origin === url.origin) {
+      if (url.pathname === window.location.pathname) {
+        return !url.hash
+      }
+      return true
+    }
+  } catch (e) { }
+  return false
+}
+
+const getOpts = ({ target }: Event): { url: URL, scroll?: boolean } | undefined => {
+  if (!isElement(target)) return
+  const a = target.closest("a")
+  if (!a) return
+  if ('routerIgnore' in a.dataset) return
+  const { href } = a
+  if (!isLocalUrl(href)) return
+  return { url: new URL(href), scroll: 'routerNoscroll' in a.dataset ? false : undefined }
+}
+
+let p: DOMParser
+async function navigate(url: URL, isBack: boolean = false) {
+  p = p || new DOMParser()
+  const contents = await fetch(`${url}`)
+    .then((res) => res.text())
+    .catch(() => {
+      window.location.assign(url)
+    })
+  if (!contents) return;
+  if (!isBack) {
+    history.pushState({}, "", url)
+    window.scrollTo({ top: 0 })
+  }
+  const html = p.parseFromString(contents, "text/html")
+  let title = html.querySelector("title")?.textContent
+  if (title) {
+    document.title = title
+  } else {
+    const h1 = document.querySelector('h1')
+    title = h1?.innerText ?? h1?.textContent ?? url.pathname
+  }
+  if (announcer.textContent !== title) {
+    announcer.textContent = title
+  }
+  announcer.dataset.persist = ''
+  html.body.appendChild(announcer)
+
+  micromorph(document.body, html.body)
+
+  // now, patch head 
+  const elementsToRemove = document.head.querySelectorAll(':not([spa-preserve])')
+  elementsToRemove.forEach(el => el.remove())
+  const elementsToAdd = html.head.querySelectorAll(':not([spa-preserve])')
+  elementsToAdd.forEach(el => document.head.appendChild(el))
+
+  if (!document.activeElement?.closest('[data-persist]')) {
+    document.body.focus()
+  }
+  delete announcer.dataset.persist
+}
+
+function createRouter() {
+  if (typeof window !== "undefined") {
+    window.addEventListener("click", async (event) => {
+      const { url } = getOpts(event) ?? {}
+      if (!url) return
+      event.preventDefault()
+      try {
+        navigate(url, false)
+      } catch (e) {
+        window.location.assign(url)
+      }
+    })
+
+    window.addEventListener("popstate", () => {
+      if (window.location.hash) return
+      try {
+        navigate(new URL(window.location.toString()), true)
+      } catch (e) {
+        window.location.reload()
+      }
+      return
+    })
+  }
+  return new class Router {
+    go(pathname: string) {
+      const url = new URL(pathname, window.location.toString())
+      return navigate(url, false)
+    }
+
+    back() {
+      return window.history.back()
+    }
+
+    forward() {
+      return window.history.forward()
+    }
+  }
+}
+
+createRouter()
+
+if (!customElements.get('route-announcer')) {
+  const attrs = {
+    'aria-live': 'assertive',
+    'aria-atomic': 'true',
+    'style': 'position: absolute; left: 0; top: 0; clip: rect(0 0 0 0); clip-path: inset(50%); overflow: hidden; white-space: nowrap; width: 1px; height: 1px'
+  }
+  customElements.define('route-announcer', class RouteAnnouncer extends HTMLElement {
+    constructor() {
+      super()
+    }
+    connectedCallback() {
+      for (const [key, value] of Object.entries(attrs)) {
+        this.setAttribute(key, value)
+      }
+    }
+  })
+}
diff --git a/quartz/plugins/index.ts b/quartz/plugins/index.ts
index 6d5d8405a..32f8bc7e2 100644
--- a/quartz/plugins/index.ts
+++ b/quartz/plugins/index.ts
@@ -4,6 +4,7 @@ import { StaticResources } from '../resources'
 import { googleFontHref, joinStyles } from '../theme'
 import { EmitCallback, PluginTypes } from './types'
 import styles from '../styles/base.scss'
+// @ts-ignore
 import spaRouterScript from '../components/scripts/spa.inline'
 
 export type ComponentResources = {
