add ndk provider

src/libs/ndk/provider.tsx

@@ -0,0 +1,44 @@
+// source: https://github.com/nostr-dev-kit/ndk-react/
+import NDK from '@nostr-dev-kit/ndk';
+import { PropsWithChildren, createContext, useContext } from 'react';
+
+import { NDKInstance } from '@libs/ndk/instance';
+
+interface NDKContext {
+  ndk: NDK;
+  relayUrls: string[];
+  loadNdk: (_: string[]) => void;
+}
+
+const NDKContext = createContext<NDKContext>({
+  ndk: new NDK({}),
+  relayUrls: [],
+  loadNdk: undefined,
+});
+
+const NDKProvider = ({ children }: PropsWithChildren<object>) => {
+  const { ndk, relayUrls, loadNdk } = NDKInstance();
+
+  if (ndk)
+    return (
+      <NDKContext.Provider
+        value={{
+          ndk,
+          relayUrls,
+          loadNdk,
+        }}
+      >
+        {children}
+      </NDKContext.Provider>
+    );
+};
+
+const useNDK = () => {
+  const context = useContext(NDKContext);
+  if (context === undefined) {
+    throw new Error('import NDKProvider to use useNDK');
+  }
+  return context;
+};
+
+export { NDKProvider, useNDK };