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import { ApiError } from "@/client/lib/api-contract";
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import { getStoredBookmark, setStoredBookmark } from "@/client/lib/storage";
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export const D1_BOOKMARK_HEADER = "x-anvil-d1-bookmark";
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export const SESSION_EXPIRED_EVENT = "anvil:session-expired";
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interface ErrorEnvelope {
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  error?: {
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    code?: string;
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    message?: string;
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    details?: unknown;
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  };
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}
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export interface RequestOptions<T> {
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  path: string;
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  method: "GET" | "POST" | "PATCH" | "PUT" | "DELETE";
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  body?: unknown;
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  decode?: (value: unknown) => T;
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}
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const parseErrorResponse = async (response: Response): Promise<ApiError> => {
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  let payload: ErrorEnvelope | null = null;
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  try {
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    payload = (await response.json()) as ErrorEnvelope;
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  } catch {
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    // Keep the HTTP status fallback when the error body is empty or malformed.
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  }
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  return new ApiError(
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    response.status,
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    payload?.error?.code ?? `http_${response.status}`,
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    payload?.error?.message ?? `Request failed with status ${response.status}.`,
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    payload?.error?.details,
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  );
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};
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export const request = async <T>({ path, method, body, decode }: RequestOptions<T>): Promise<T> => {
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  const headers = new Headers({
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    accept: "application/json",
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  });
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  const bookmark = getStoredBookmark();
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  if (bookmark) {
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    headers.set(D1_BOOKMARK_HEADER, bookmark);
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  }
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  if (body !== undefined) {
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    headers.set("content-type", "application/json; charset=utf-8");
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  }
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  let response: Response;
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  try {
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    response = await fetch(path, {
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      method,
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      headers,
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      body: body === undefined ? undefined : JSON.stringify(body),
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      credentials: "same-origin",
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    });
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  } catch (error) {
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    throw new ApiError(503, "network_error", "Request failed. The backend may not be ready yet.", error);
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  }
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  const nextBookmark = response.headers.get(D1_BOOKMARK_HEADER);
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  if (nextBookmark) {
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    setStoredBookmark(nextBookmark);
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  }
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  if (!response.ok) {
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    const apiError = await parseErrorResponse(response);
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    if (apiError.code === "invalid_session") {
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      window.dispatchEvent(new CustomEvent(SESSION_EXPIRED_EVENT));
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    }
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    throw apiError;
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  }
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  if (!decode) {
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    return undefined as T;
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  }
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  let payload: unknown;
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  try {
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    payload = (await response.json()) as unknown;
87
  } catch (error) {
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    throw new ApiError(500, "invalid_response", "Server returned malformed JSON.", error);
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  }
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  try {
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    return decode(payload);
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  } catch (error) {
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    throw new ApiError(500, "invalid_response", "Server response failed contract validation.", error);
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  }
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};