/**
 * Wire contract for idempotent Runtime Postgres -> Convex Run Ledger delivery.
 *
 * Producers must use these builders and API boundaries must use these
 * validators. Keeping the format here prevents the scheduler and runtime route
 * from admitting different lifecycle-event keys.
 */

const UUID_PATTERN =
  /^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
const SHA256_HEX_PATTERN = /^[0-9a-f]{64}$/i;

function requireRunId(runId: string): void {
  if (!runId.trim()) {
    throw new Error('Run Ledger projection idempotency key requires a run id.');
  }
}

function requireDeliveryKey(deliveryKey: string): void {
  if (!UUID_PATTERN.test(deliveryKey)) {
    throw new Error(
      'Run Ledger projection delivery key must be a canonical UUID.',
    );
  }
}

export function buildRunLedgerStartIdempotencyKey(input: {
  runId: string;
  deliveryKey: string;
}): string {
  requireRunId(input.runId);
  requireDeliveryKey(input.deliveryKey);
  return `run-started:${input.runId}:${input.deliveryKey}`;
}

export function buildRunLedgerTerminalIdempotencyKey(input: {
  runId: string;
  deliveryKey: string;
}): string {
  requireRunId(input.runId);
  requireDeliveryKey(input.deliveryKey);
  return `run-terminal:${input.runId}:${input.deliveryKey}`;
}

/**
 * Compatibility key for the one-row projector. The `run-terminal` prefix was
 * historically used for every non-start row, including lifecycle events, so
 * changing it during a retry could append the same fact twice across deploys.
 */
export function buildRunLedgerSingleEventIdempotencyKey(input: {
  runId: string;
  deliveryKey: string;
}): string {
  return buildRunLedgerTerminalIdempotencyKey(input);
}

export function buildRunLedgerEventsIdempotencyKey(input: {
  runId: string;
  deliveryDigest: string;
}): string {
  requireRunId(input.runId);
  if (!SHA256_HEX_PATTERN.test(input.deliveryDigest)) {
    throw new Error(
      'Run Ledger projection delivery digest must be a SHA-256 hex value.',
    );
  }
  return `run-events:${input.runId}:${input.deliveryDigest}`;
}

export function isValidRunLedgerStartIdempotencyKey(input: {
  runId: string;
  idempotencyKey: string;
}): boolean {
  const prefix = `run-started:${input.runId}:`;
  return (
    input.idempotencyKey.startsWith(prefix) &&
    UUID_PATTERN.test(input.idempotencyKey.slice(prefix.length))
  );
}

export function isValidRunLedgerAppendIdempotencyKey(input: {
  runId: string;
  idempotencyKey: string;
}): boolean {
  const terminalPrefix = `run-terminal:${input.runId}:`;
  if (input.idempotencyKey.startsWith(terminalPrefix)) {
    return UUID_PATTERN.test(input.idempotencyKey.slice(terminalPrefix.length));
  }

  const eventsPrefix = `run-events:${input.runId}:`;
  return (
    input.idempotencyKey.startsWith(eventsPrefix) &&
    SHA256_HEX_PATTERN.test(input.idempotencyKey.slice(eventsPrefix.length))
  );
}