From cab3ed4ad4f34a0f3e6ba9629c3dc9be31686796 Mon Sep 17 00:00:00 2001
From: Shinigami92 <chrissi92@hotmail.de>
Date: Sat, 10 Dec 2022 23:09:11 +0100
Subject: [PATCH] feat: improve status image quality

---
 components/status/StatusPreviewCard.vue | 13 +++++--
 server/api/og-image.ts                  | 45 +++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 2 deletions(-)
 create mode 100644 server/api/og-image.ts

diff --git a/components/status/StatusPreviewCard.vue b/components/status/StatusPreviewCard.vue
index f4719f68..83fbcc7c 100644
--- a/components/status/StatusPreviewCard.vue
+++ b/components/status/StatusPreviewCard.vue
@@ -8,11 +8,20 @@ const props = defineProps<{
   /** When it is root card in the list, not appear as a child card */
   root?: boolean
 }>()
+const image = ref(props.card.image)
 const alt = $computed(() => `${props.card.title} - ${props.card.title}`)
 const isSquare = $computed(() => props.smallPictureOnly || props.card.width === props.card.height)
 const description = $computed(() => props.card.description ? props.card.description : new URL(props.card.url).hostname)
 
 // TODO: handle card.type: 'photo' | 'video' | 'rich';
+
+$fetch<string>('/api/og-image', {
+  params: { cardUrl: props.card.url },
+}).then((ogImageUrl) => {
+  // Only override if ogImageUrl is not empty
+  if (ogImageUrl)
+    image.value = ogImageUrl
+}).catch(() => {})
 </script>
 
 <template>
@@ -29,7 +38,7 @@ const description = $computed(() => props.card.description ? props.card.descript
     target="_blank"
   >
     <div
-      v-if="card.image"
+      v-if="image"
       flex flex-col
       display-block of-hidden
 
@@ -42,7 +51,7 @@ const description = $computed(() => props.card.description ? props.card.descript
     >
       <CommonBlurhash
         :blurhash="card.blurhash"
-        :src="card.image"
+        :src="image"
         :width="card.width"
         :height="card.height"
         :alt="alt"
diff --git a/server/api/og-image.ts b/server/api/og-image.ts
new file mode 100644
index 00000000..4c194509
--- /dev/null
+++ b/server/api/og-image.ts
@@ -0,0 +1,45 @@
+const inMemoryCache = new Map<string, { url: string; lastUsed: number }>()
+
+export default defineEventHandler(async (event) => {
+  const { cardUrl } = getQuery(event)
+
+  if (!cardUrl) {
+    throw createError({
+      statusCode: 422,
+      statusMessage: 'Missing cardUrl.',
+    })
+  }
+
+  if (typeof cardUrl !== 'string') {
+    throw createError({
+      statusCode: 422,
+      statusMessage: 'cardUrl must be string.',
+    })
+  }
+
+  if (inMemoryCache.has(cardUrl)) {
+    const { url } = inMemoryCache.get(cardUrl)!
+    await send(event, url)
+
+    // Remove oldest entry if cache is too big
+    if (inMemoryCache.size > 5000) {
+      const oldestEntry = [...inMemoryCache.entries()].reduce(
+        (acc, [key, { lastUsed }]) => (lastUsed < acc.lastUsed ? { key, lastUsed } : acc),
+        { key: '', lastUsed: Infinity },
+      )
+      inMemoryCache.delete(oldestEntry.key)
+    }
+
+    return
+  }
+
+  const result = await $fetch<string>(cardUrl)
+  let ogImageUrl: string | null | undefined = null
+
+  const match = result.match(/<meta property="og:image" content="([^"]+)" \/>/)
+  ogImageUrl = match?.[1] ?? ''
+
+  inMemoryCache.set(cardUrl, { url: ogImageUrl, lastUsed: Date.now() })
+
+  await send(event, ogImageUrl)
+})