feat(steamdb): create HTML scraper to extract version and build ID from SteamDB

lib/steamdb/scrape.ts

@@ -0,0 +1,91 @@
+import { getCachedVersion, setCachedVersion, isOnCooldown, setCooldown, setExtendedCooldown } from "./cache"
+
+const STEAMDB_APP_URL = "https://steamdb.info/app"
+
+interface ScrapeResult {
+  versionString: string | null
+  buildId: string | null
+}
+
+export async function scrapeSteamDBVersion(steamAppId: number): Promise<ScrapeResult & { cached: boolean }> {
+  // Check cache first
+  const cached = getCachedVersion(steamAppId)
+  if (cached) {
+    return { versionString: cached.versionString, buildId: cached.buildId, cached: true }
+  }
+
+  // Check cooldown
+  if (isOnCooldown(steamAppId)) {
+    return { versionString: null, buildId: null, cached: true }
+  }
+
+  // If scraping is disabled via env, skip
+  if (process.env.STEAMDB_SCRAPING_ENABLED === "false") {
+    return { versionString: null, buildId: null, cached: true }
+  }
+
+  try {
+    const res = await fetch(`${STEAMDB_APP_URL}/${steamAppId}/`, {
+      headers: {
+        "User-Agent": "DeckyVault/1.0 (deckyvault.xyz; game version lookup)",
+        "Accept": "text/html",
+      },
+      signal: AbortSignal.timeout(10000),
+    })
+
+    if (res.status === 429 || res.status === 403) {
+      setExtendedCooldown(steamAppId)
+      return { versionString: null, buildId: null, cached: true }
+    }
+
+    if (!res.ok) {
+      setCooldown(steamAppId, 30)
+      return { versionString: null, buildId: null, cached: true }
+    }
+
+    const html = await res.text()
+    const result = parseSteamDBHtml(html)
+
+    setCachedVersion(steamAppId, result.versionString, result.buildId)
+    return { ...result, cached: false }
+  } catch {
+    setCooldown(steamAppId, 30)
+    return { versionString: null, buildId: null, cached: true }
+  }
+}
+
+function parseSteamDBHtml(html: string): ScrapeResult {
+  let versionString: string | null = null
+  let buildId: string | null = null
+
+  // Strategy 1: Look for "Last known name" in meta or table rows
+  const lastKnownMatch = html.match(/Last known name[^<]*<[^>]*>([^<]+)</i)
+  if (lastKnownMatch) {
+    versionString = lastKnownMatch[1].trim()
+  }
+
+  // Strategy 2: Try JSON-LD for version
+  const jsonLdMatch = html.match(/<script type="application\/ld\+json">([\s\S]*?)<\/script>/)
+  if (jsonLdMatch) {
+    try {
+      const parsed = JSON.parse(jsonLdMatch[1])
+      if (parsed.version) {
+        versionString = versionString || parsed.version
+      }
+    } catch {
+      // JSON-LD parse failure is non-fatal
+    }
+  }
+
+  // Strategy 3: Extract build ID from the page
+  const buildMatch = html.match(/Build\s*ID[^<]*<\/td>\s*<td[^>]*>(\d+)/i)
+     || html.match(/buildid[^>]*>(\d+)/i)
+  if (buildMatch) {
+    buildId = buildMatch[1].trim()
+  }
+
+  return { versionString, buildId }
+}
+
+// Export for testing
+export const _parseSteamDBHtml = parseSteamDBHtml