ng-eventually/packages/client/src/shared-wallet/physical.ts

/**
 * physical — the polyfill's OWN machinery, operating on the PHYSICAL user.
 *
 * ── Two levels, two APIs, and only one of them is the app's ───────────────
 * NextGraph sees exactly one user: the physical one, whose wallet everybody opens.
 * On top of it the library fabricates **virtual users** — what the consumer calls
 * an identity. Those are two different levels, and conflating them is how a
 * boundary gets a hole in it:
 *
 * | | Level | Who calls it | Guarded |
 * |---|---|---|---|
 * | `docs.*`, `subscribeDoc` | the **virtual user** | the consumer app, and the library on the user's behalf | YES — confined to the connected user (`reach.ts`) |
 * | this module | the **physical user** | the library's own machinery, and nothing else | no — it *is* the machinery the boundary is built on |
 *
 * **Nothing here is exported from the package.** `index.ts` must never re-export
 * this module: an app holding these functions could read any document of any
 * virtual user, which is precisely the boundary they exist below.
 *
 * ── Why a separate module rather than exemptions ──────────────────────────
 * The store-root pointer and the doc-shim — the index of virtual users — cannot be
 * subject to the boundary: resolving *which* documents a virtual user owns is what
 * makes virtual users exist at all. An earlier version handled that with a list of
 * exempt NURIs consulted by the guard. Separating the FUNCTIONS is stronger: the
 * machinery does not call the guarded primitive and get waved through, it calls a
 * different primitive that was never guarded. There is no exemption list to widen,
 * to get wrong, or to infer.
 *
 * The rule for deciding which side a call belongs to:
 *
 *   > Does this operate on the index of virtual users (the shim), or on the content
 *   > of one virtual user? The first is machinery; everything else is the user's,
 *   > and is confined.
 *
 * A virtual user's own stores, its inbox and its documents are the user's — they go
 * through `docs.*` and are guarded, even though the library is what calls them.
 *
 * At migration this module disappears with the shim: there is no physical/virtual
 * split once each user opens their own wallet.
 */

import { getConfig } from "../polyfill";
import { logAccess } from "./access-log";
import { isNuri } from "../model/nuri";
import type { Nuri } from "../model/types";

/**
 * Create a document as the PHYSICAL user — the shim's own documents (the doc-shim,
 * a virtual user's store documents at provisioning time, an inbox document).
 *
 * Creation is the one operation with no boundary to check: the document does not
 * exist yet, so nobody can hold its cap. What matters is who is credited with it
 * afterwards, which the caller decides by filing the cap among the caps that holder holds.
 */
export async function physicalCreate(
  sessionId: string,
  crdt = "Graph",
  cls = "data:graph",
  dest = "store",
  store?: unknown,
): Promise<Nuri> {
  const { ng } = getConfig();
  const nuri = await ng.doc_create(sessionId, crdt, cls, dest, store);
  if (typeof nuri !== "string" || !isNuri(nuri)) {
    throw new Error(
      `[ng-eventually] physicalCreate: the broker returned something that is not a NextGraph reference: ${JSON.stringify(nuri)}`,
    );
  }
  logAccess("WRITE", nuri, "physicalCreate");
  return nuri;
}

/**
 * Read as the PHYSICAL user — for the shim only (the store-root pointer, the
 * doc-shim's account records).
 *
 * Unguarded by design: this is how the library learns which documents a virtual
 * user owns, so it cannot itself depend on knowing that. Do not reach for it to
 * read a virtual user's content — that is `docs.sparqlQuery`, which is confined.
 */
export async function physicalQuery(
  sessionId: string,
  query: string,
  base: string | undefined,
  anchor: Nuri,
  label = "physicalQuery",
): Promise<unknown> {
  const { ng } = getConfig();
  const result = await ng.sparql_query(sessionId, query, base, anchor);
  logAccess("READ", anchor, label, " (physical)");
  return result;
}

/** Write as the PHYSICAL user — the shim's own records. See {@link physicalQuery}. */
export async function physicalUpdate(
  sessionId: string,
  query: string,
  anchor: Nuri,
  label = "physicalUpdate",
): Promise<void> {
  const { ng } = getConfig();
  logAccess("WRITE", anchor, label, " (physical)");
  return ng.sparql_update(sessionId, query, anchor);
}