feat: initial version

Signed-off-by: Sebastian <krupinski01@gmail.com>

src/services/viewer.ts

@@ -0,0 +1,54 @@
+import { useIntegrationStore } from '@KTXC'
+import type { ModuleIntegrationItem } from '@KTXC/types/moduleTypes'
+
+export const MEDIA_VIEWER_FORMAT_POINT = 'media_viewer_format'
+
+function mimeMatchesPattern(mime: string, pattern: string): boolean {
+  if (pattern.endsWith('/*')) {
+    // e.g. 'image/*' matches 'image/png', 'image/jpeg', …
+    return mime.startsWith(pattern.slice(0, -1))
+  }
+  return mime === pattern
+}
+
+function viewerMatchesMime(
+  mime: string,
+  mimeTypes?: string[],
+  mimePatterns?: string[],
+): boolean {
+  if (mimeTypes?.includes(mime)) return true
+  if (mimePatterns) {
+    for (const pattern of mimePatterns) {
+      if (mimeMatchesPattern(mime, pattern)) return true
+    }
+  }
+  return false
+}
+
+/**
+ * Returns the highest-priority registered viewer that can handle `mime`,
+ * or `null` if none is found.
+ */
+export function findViewer(mime: string): ModuleIntegrationItem | null {
+  const integrationStore = useIntegrationStore()
+  // getItems() already returns items sorted by priority (ascending)
+  const viewers = integrationStore.getItems(MEDIA_VIEWER_FORMAT_POINT) as ModuleIntegrationItem[]
+  for (const viewer of viewers) {
+    if (
+      viewerMatchesMime(
+        mime,
+        viewer.meta?.mimeTypes as string[] | undefined,
+        viewer.meta?.mimePatterns as string[] | undefined,
+      )
+    ) {
+      return viewer
+    }
+  }
+  return null
+}
+
+/** True if any registered viewer can render this MIME type. */
+export function hasViewer(mime: string): boolean {
+  if (!mime) return false
+  return findViewer(mime) !== null
+}