import { ATTRIBUTION_FILENAME, type AttributionRecord } from "./attribution";
import { sidecar, sidecarField } from "./sidecar-server";

// Validate the SHAPE, not just the parse. A half-written sidecar must read as
// absent everywhere — the same rule diarization-server.ts's hasDiarization
// encodes, and here it matters for a second reason: a malformed file that read
// as "present" would also read as a DOWNGRADE guard, and could block the
// diarized lane from ever writing a real record.
export function coerceAttribution(value: unknown): AttributionRecord | null {
  const parsed = value as Partial<AttributionRecord> | null;
  if (
    typeof parsed?.videoId === "string" &&
    typeof parsed.generatedAt === "string" &&
    Array.isArray(parsed.speakers) &&
    Array.isArray(parsed.segments) &&
    !!parsed.provenance &&
    typeof parsed.provenance.method === "string"
  ) {
    return parsed as AttributionRecord;
  }
  return null;
}

// Compact (one line + "\n"), as it always was. The write is atomic (tmp +
// rename), which is what lets loadAttribution treat "parsed but wrong shape"
// as a real anomaly rather than the expected state of a file being written.
export const attributionSidecar = sidecar(
  ATTRIBUTION_FILENAME,
  sidecarField(coerceAttribution),
  { indent: 0 },
);

export const {
  path: attributionPath,
  load: loadAttribution,
  write: writeAttribution,
} = attributionSidecar;