import type { AppContext } from '@voltro/runtime'

// Write the incoming CRDT update to the `body` column. The handler looks like a
// plain overwrite — but `body` is a `crdtText()` column, so the runtime's
// MutationStore intercepts the write: it reads the STORED state and folds the
// incoming update in with `mergeCrdtStates` (from @voltro/local-first) BEFORE
// persisting. That authoritative server merge is what makes concurrent edits
// converge; the reactive engine then broadcasts the merged row to every
// subscriber. This handler stays a one-liner precisely because the convergence
// lives in the write path, not here.
// No `if (row === null)` branch here, and that is deliberate. `documents` is
// `.with(tenant())`, so a keyed write the caller may not perform does not come
// back as `null` — the store THROWS `TenantRowNotFound`, identically for "no
// such row" and "someone else's row". Re-checking for `null` would be dead code,
// and answering it with a 404 would undo the point: two different answers for
// the two cases turn any keyed write into a cross-tenant existence oracle.
//
// The typed error reaches the client as itself (`_tag`, payload and prototype
// intact), so a `catchTag('TenantRowNotFound')` on the caller is the handling
// site — not a hand-rolled status here.
const execute = async (
  input: { id: string; update: Uint8Array },
  ctx: AppContext,
) => ctx.store.update('documents', input.id, { body: input.update })

export default execute