Add support for image popovers (#854)

* feat(popover): Add support for images

* fix: run prettier

* feat(popover): use switch logic for content types & adjust styles

* feat(popover): Add content type data tag for popover-inner class

docs/features/popover previews.md

@@ -8,6 +8,8 @@ By default, Quartz only fetches previews for pages inside your vault due to [COR
 
 When [[creating components|creating your own components]], you can include this `popover-hint` class to also include it in the popover.
 
+Similar to Obsidian, [[quartz layout.png|images referenced using wikilinks]] can also be viewed as popups.
+
 ## Configuration
 
 - Remove popovers: set the `enablePopovers` field in `quartz.config.ts` to be `false`.

quartz/components/scripts/popover.inline.ts

@@ -37,9 +37,7 @@ async function mouseEnterHandler(
   targetUrl.hash = ""
   targetUrl.search = ""
 
-  const contents = await fetch(`${targetUrl}`)
-    .then((res) => res.text())
-    .catch((err) => {
+  const response = await fetch(`${targetUrl}`).catch((err) => {
     console.error(err)
   })
 
@@ -48,18 +46,38 @@ async function mouseEnterHandler(
     return
   }
 
-  if (!contents) return
-  const html = p.parseFromString(contents, "text/html")
-  normalizeRelativeURLs(html, targetUrl)
-  const elts = [...html.getElementsByClassName("popover-hint")]
-  if (elts.length === 0) return
+  if (!response) return
+  const contentType = response.headers.get("Content-Type")
+  const contentTypeCategory = contentType?.split("/")[0] ?? "text"
 
   const popoverElement = document.createElement("div")
   popoverElement.classList.add("popover")
   const popoverInner = document.createElement("div")
   popoverInner.classList.add("popover-inner")
   popoverElement.appendChild(popoverInner)
+
+  popoverInner.dataset.contentType = contentTypeCategory
+
+  switch (contentTypeCategory) {
+    case "image":
+      const img = document.createElement("img")
+
+      response.blob().then((blob) => {
+        img.src = URL.createObjectURL(blob)
+      })
+      img.alt = targetUrl.pathname
+
+      popoverInner.appendChild(img)
+      break
+    default:
+      const contents = await response.text()
+      const html = p.parseFromString(contents, "text/html")
+      normalizeRelativeURLs(html, targetUrl)
+      const elts = [...html.getElementsByClassName("popover-hint")]
+      if (elts.length === 0) return
+
       elts.forEach((elt) => popoverInner.appendChild(elt))
+  }
 
   setPosition(popoverElement)
   link.appendChild(popoverElement)

quartz/components/styles/popover.scss

@@ -38,6 +38,17 @@
     white-space: normal;
   }
 
+  & > .popover-inner[data-content-type="image"] {
+    padding: 0;
+    max-height: 100%;
+
+    img {
+      margin: 0;
+      border-radius: 0;
+      display: block;
+    }
+  }
+
   h1 {
     font-size: 1.5rem;
   }