fix: share board offline state between post form and reply modal

src/components/board-offline-alert/board-offline-alert.tsx

@@ -0,0 +1,67 @@
+import { useMemo } from 'react';
+import useSubplebbitsStore from '@bitsocialhq/bitsocial-react-hooks/dist/stores/subplebbits';
+import { normalizeBoardAddress, useDirectoryByAddress } from '../../hooks/use-directories';
+import useIsSubplebbitOffline from '../../hooks/use-is-subplebbit-offline';
+import { useResolvedSubplebbitAddress } from '../../hooks/use-resolved-subplebbit-address';
+
+const BOARD_ALIAS_SUFFIXES = ['.bso', '.eth'] as const;
+
+const getBoardAddressCandidates = (addresses: Array<string | undefined>) => {
+  const uniqueCandidates = new Set<string>();
+
+  const addCandidate = (candidate: string | undefined) => {
+    if (candidate) {
+      uniqueCandidates.add(candidate);
+    }
+  };
+
+  addresses.forEach((address) => {
+    if (!address) {
+      return;
+    }
+
+    addCandidate(address);
+
+    const normalizedAddress = normalizeBoardAddress(address);
+    addCandidate(normalizedAddress);
+    BOARD_ALIAS_SUFFIXES.forEach((suffix) => addCandidate(`${normalizedAddress}${suffix}`));
+  });
+
+  return Array.from(uniqueCandidates);
+};
+
+interface BoardOfflineAlertProps {
+  className: string;
+  hidden?: boolean;
+  subplebbitAddress?: string;
+}
+
+const BoardOfflineAlert = ({ className, hidden = false, subplebbitAddress }: BoardOfflineAlertProps) => {
+  const resolvedSubplebbitAddress = useResolvedSubplebbitAddress();
+  const directoryEntry = useDirectoryByAddress(resolvedSubplebbitAddress || subplebbitAddress);
+  const addressCandidates = useMemo(
+    () => getBoardAddressCandidates([resolvedSubplebbitAddress, directoryEntry?.address, subplebbitAddress]),
+    [directoryEntry?.address, resolvedSubplebbitAddress, subplebbitAddress],
+  );
+
+  // Probe common aliases first so loading/offline state stays consistent across route and post payload address formats.
+  const subplebbit = useSubplebbitsStore((state) => {
+    for (const candidate of addressCandidates) {
+      const matchedSubplebbit = state.subplebbits[candidate];
+      if (matchedSubplebbit) {
+        return matchedSubplebbit;
+      }
+    }
+
+    return undefined;
+  });
+  const { isOffline, isOnlineStatusLoading, offlineTitle } = useIsSubplebbitOffline(subplebbit);
+
+  if (hidden || (!isOffline && !isOnlineStatusLoading)) {
+    return null;
+  }
+
+  return <div className={className}>{offlineTitle}</div>;
+};
+
+export default BoardOfflineAlert;