/**
 * Anthropic API model id → the Officer id that most nearly names it.
 *
 * Two id spaces meet here. A transcript records what the API served (`claude-opus-5`); Officer's picker
 * offers what the CLI accepts (`claude-code/opus`, `claude-code/opus[1m]`). This translates one to the
 * other, and it is **deliberately lossy in one direction only** — that is the whole reason
 * `chat_session_models` exists:
 *
 *   - `opus` and `opus[1m]` both serve `claude-opus-5`, so the 1M variant cannot be recovered.
 *   - `opusplan` serves whichever of opus/sonnet answered that turn, so it cannot be recognised at all.
 *   - `mythos` has no Officer entry (Project Glasswing only), so it resolves to null rather than to a
 *     neighbouring family — offering a model this machine may not reach is worse than offering none.
 *
 * So this is the FALLBACK for a session that has not taken a turn since the table landed, and the seed for
 * the backfill. A real turn overwrites its guess with the exact alias the user picked. Never use it to
 * decide what to run — only to decide what to display.
 *
 * Matching is by FAMILY PREFIX rather than an exhaustive id list, because the API ids are not uniform:
 * `claude-haiku-4-5-20251001` carries a date suffix while `claude-fable-5` does not, and new versions ship
 * without warning. A prefix match keeps a model released tomorrow resolving to the right family instead of
 * to null.
 */

/** Claude Code's own marker for an entry it generated itself. Not a model, and must never be stored. */
export const SYNTHETIC_MODEL = '<synthetic>';

const FAMILIES: { prefix: string; officerId: string }[] = [
  { prefix: 'claude-fable', officerId: 'claude-code/fable' },
  { prefix: 'claude-opus', officerId: 'claude-code/opus' },
  { prefix: 'claude-sonnet', officerId: 'claude-code/sonnet' },
  { prefix: 'claude-haiku', officerId: 'claude-code/haiku' },
];

/**
 * The Officer model id for an API model id, or null when there is no honest answer.
 *
 * Null for `<synthetic>`, for mythos, for an OpenCode model, and for anything unrecognised. Callers treat
 * null as "we do not know", which renders as no model rather than as a guess.
 */
export function officerModelForApiModel(apiModel: string | null | undefined): string | null {
  if (!apiModel || apiModel === SYNTHETIC_MODEL) return null;
  const id = apiModel.trim().toLowerCase();
  if (!id) return null;
  const family = FAMILIES.find((f) => id.startsWith(f.prefix));
  return family?.officerId ?? null;
}

/** Whether a transcript entry's model is a real model rather than Claude Code's synthetic marker. */
export const isRealModel = (apiModel: string | null | undefined): boolean => !!apiModel && apiModel !== SYNTHETIC_MODEL;