// src/lib/document-status.ts
/**
 * Turns a parse outcome into the status fields written back onto an
 * uploaded document row.
 *
 * This exists because the three synchronous importers used to create
 * their audit row with `status: "processed"` hardcoded *before* a single
 * data row was inserted, and never updated it again. Production ended up
 * with 19 plant_hours batches marked processed against one actual log
 * row, and no way for anyone to notice.
 *
 * Pure: no PocketBase, no clock, no I/O. The caller supplies `now`.
 */
import type { DocumentStatus, RowError } from "./pb-types";

/** How many per-row errors we persist. Enough to fix a sheet, bounded. */
export const MAX_ROW_ERRORS = 200;

export type ParseOutcome = {
  /** Rows the parser found in the file, before validation. */
  rowsTotal: number;
  /** Rows that actually became records. */
  rowsCreated: number;
  rowErrors: RowError[];
};

export type DocumentOutcomeFields = {
  processing_status: DocumentStatus;
  processed_at: string;
  rows_total: number;
  rows_created: number;
  rows_failed: number;
  row_errors: RowError[];
  last_error: string;
};

export function resolveDocumentOutcome(
  outcome: ParseOutcome,
  now: Date,
): DocumentOutcomeFields {
  const { rowsTotal, rowsCreated, rowErrors } = outcome;
  const rowsFailed = rowErrors.length;

  let processing_status: DocumentStatus;
  let last_error: string;

  if (rowsTotal === 0) {
    // A file we could open but that held no data rows. Almost always the
    // wrong file or the wrong sheet — the operator needs to know.
    processing_status = "failed";
    last_error = "no data rows found in file";
  } else if (rowsCreated === 0) {
    // Parsed fine, landed nothing. Never call this processed.
    processing_status = "failed";
    last_error = rowErrors[0]?.reason ?? "no rows could be imported";
  } else if (rowsFailed > 0) {
    // Partial. The rows that landed are real, so this is processed — but
    // the failures are recorded and surfaced.
    processing_status = "processed";
    last_error = `${rowsFailed} of ${rowsTotal} rows failed`;
  } else {
    processing_status = "processed";
    last_error = "";
  }

  return {
    processing_status,
    processed_at: now.toISOString(),
    rows_total: rowsTotal,
    rows_created: rowsCreated,
    rows_failed: rowsFailed,
    row_errors: rowErrors.slice(0, MAX_ROW_ERRORS),
    last_error,
  };
}