refactor(auto-thumbnail): [PKG-AUTO-THUMB-03] type internal extraction contracts

packages/artplayer-plugin-auto-thumbnail/src/video.ts

@@ -0,0 +1,24 @@
+import type { ExtractionJob } from './types'
+
+export default function createVideo(job: ExtractionJob) {
+  const video = document.createElement('video')
+  job.own(() => video.remove())
+  job.own(() => video.load())
+  job.own(() => video.removeAttribute('src'))
+  job.own(() => video.pause())
+  for (const property of ['onloadedmetadata', 'onloadeddata', 'onseeked', 'onerror'] as const)
+    job.own(() => { video[property] = null })
+  if (!job.active())
+    return video
+  video.crossOrigin = 'anonymous'
+  video.muted = true
+  video.playsInline = true
+  video.tabIndex = -1
+  video.setAttribute('aria-hidden', 'true')
+  // WebKit needs a rendered box; display:none and a 1px box lose decoded pixels.
+  video.style.cssText = 'position:fixed;left:0;top:0;visibility:hidden;pointer-events:none;display:block;width:auto;height:auto;max-width:none;max-height:none'
+  document.documentElement.appendChild(video)
+  if (!job.active())
+    video.remove()
+  return video
+}