Refactor clawx (#344)

Co-authored-by: ashione <skyzlxuan@gmail.com>

src/lib/host-api.ts

@@ -0,0 +1,42 @@
+const HOST_API_PORT = 3210;
+const HOST_API_BASE = `http://127.0.0.1:${HOST_API_PORT}`;
+
+async function parseResponse<T>(response: Response): Promise<T> {
+  if (!response.ok) {
+    let message = `${response.status} ${response.statusText}`;
+    try {
+      const payload = await response.json() as { error?: string };
+      if (payload?.error) {
+        message = payload.error;
+      }
+    } catch {
+      // ignore body parse failure
+    }
+    throw new Error(message);
+  }
+
+  if (response.status === 204) {
+    return undefined as T;
+  }
+
+  return await response.json() as T;
+}
+
+export async function hostApiFetch<T>(path: string, init?: RequestInit): Promise<T> {
+  const response = await fetch(`${HOST_API_BASE}${path}`, {
+    ...init,
+    headers: {
+      'Content-Type': 'application/json',
+      ...(init?.headers || {}),
+    },
+  });
+  return parseResponse<T>(response);
+}
+
+export function createHostEventSource(path = '/api/events'): EventSource {
+  return new EventSource(`${HOST_API_BASE}${path}`);
+}
+
+export function getHostApiBase(): string {
+  return HOST_API_BASE;
+}