Embeds

@kowloon/client/embeds is a pure, client-side registry -- no HTTP calls of its own. It's the single, shared recognizer for "what's embeddable" -- the exact same code is used by the server's /preview endpoint, the web frontend, and the mobile app, so the definition of what gets rendered as a rich embed versus a plain link lives in exactly one audited place rather than being reimplemented three times.

`resolveEmbed(url)`

import { resolveEmbed, isEmbeddable } from '@kowloon/client/embeds'

const embed = resolveEmbed(url)
// { provider, mode: 'inline' | 'linkout', embedUrl?, thumbnail?, aspectRatio, title?, allow?, sandbox? }
// or null if the URL isn't recognized by any provider

aspectRatio defaults to 16/9 if the provider doesn't specify one. A null result means: render this as a plain link, not an embed.

isEmbeddable(url) is a boolean convenience wrapper over the same check.

Providers

Only youtube is registered today. The YouTube provider recognizes a broad set of URL shapes:

youtube.com/watch?v=...
youtu.be/...
/shorts/...
/embed/...
/live/...
/v/...
music.youtube.com/...

It also parses t/start query params into a playback start offset, accepting several formats: 90 (bare seconds), 90s, 1m30s, 1h2m3s.

EMBED_WEBVIEW_USER_AGENT is also exported -- a spoofed desktop-Chrome user-agent string. Android's native WebView identifies itself with a "wv" token in its user agent, and YouTube specifically rejects playback for that token ("video unavailable"). Mobile embeds need to send this spoofed UA to work at all; the web frontend doesn't need it since it's already running in a real browser.

Adding a provider

Drop a new file under providers/ exporting { name, hosts, match(url), embed(match) }, and register it in the PROVIDERS list. match() determines whether a URL belongs to this provider (and extracts whatever embed() needs); embed() builds the final descriptor.