import { RECORD_FIELDS, withoutRecordFields } from '../db/identity.ts';
import type { Store } from '../db/store.ts';
import type { MockServerConfig, Row } from '../types.ts';
import { isLegacyFidelity } from './fidelity.ts';

export type RowOperation = 'INSERT' | 'MODIFY' | 'DELETE';

// Stamps a row with DETAILS.OPERATION/ROW_REF, the only fields the client's
// dataServerResultFilter uses to distinguish INSERT/MODIFY/DELETE on a
// QUERY_UPDATE (both for the snapshot pages and later unsolicited pushes on
// the same SOURCE_REF — the envelope is otherwise identical). OPERATION must
// be exactly 'INSERT' | 'MODIFY' | 'DELETE'; anything else is silently
// dropped client-side. GSF puts ROW_REF in DETAILS only; clients copy it onto
// the row themselves (`row.DETAILS[rowId] ?? row[rowId]`). Legacy mode also
// set it on the row itself, as this engine did up to 15.47.
export function stampRow(row: Row, rowRef: unknown, operation: RowOperation, legacy = false): Row {
  const DETAILS = { OPERATION: operation, ROW_REF: rowRef };
  return legacy ? { ...row, ROW_REF: rowRef, DETAILS } : { ...row, DETAILS };
}

// DETAILS.ROW_REF for a row of a dataserver's source: the record's RECORD_ID
// as a string, as GSF sends it (a view row's comes from its base row). Legacy
// mode used the pk value, or the '|'-joined composite key. Read per call, so
// flipping `fidelity` on a running server applies to the next push.
export function rowRefFor(
  config: MockServerConfig,
  store: Store,
  resourceName: string,
  row: Row,
): unknown {
  return isLegacyFidelity(config)
    ? store.getRowRef(resourceName, row)
    : store.getRecordRef(resourceName, row);
}

// RECORD_ID and TIMESTAMP on a dataserver row: the real dataserver never
// sends them unless the query's fields block names them. `projected` is the
// row already narrowed to the query's columns; `source` the stored row the
// values come from.
export function dataserverRow(projected: Row, source: Row, fields: string[] | undefined): Row {
  const row = { ...withoutRecordFields(projected) };
  for (const field of RECORD_FIELDS) {
    if (fields?.includes(field) && source[field] !== undefined) row[field] = source[field];
  }
  return row;
}