/**
 * Copyright (c) 2026 Niolla
 * All rights reserved.
 *
 * This source code is proprietary and confidential.
 * Unauthorized copying, modification, distribution, or use
 * of this file, via any medium, is strictly prohibited.
 */

// app/utils/validation/validateSupplier.util.js


const db = require("../../models");
const Supplier = db.Vendor;

const extractCellValue = (value) => {
  if (value && typeof value === "object") {
    return value.text || value.result || "";
  }
  return value?.toString().trim() || "";
};

const validateSupplierColumn = async (worksheet, columns) => {
  const supplierIdCol =
    columns.findIndex((col) => col.column_name === "supplier_id") + 1;

  if (!supplierIdCol) return;

  const supplierIds = new Set();
  const errors = [];

  // 🔹 Extract values (ONLY collect non-empty)
  for (let i = 2; i <= worksheet.rowCount; i++) {
    let value = extractCellValue(
      worksheet.getRow(i).getCell(supplierIdCol).value
    );

    if (value) {
      supplierIds.add(value);
    }
  }

  if (supplierIds.size === 0) return [];

  // 🔹 Batch DB validation
  const suppliers = await Supplier.findAll({
    where: {
      vendor_id: [...supplierIds],
    },
  });

  const validIds = new Set(suppliers.map((s) => s.vendor_id));

  // 🔹 Validate ONLY non-empty values
  for (let i = 2; i <= worksheet.rowCount; i++) {
    let value = extractCellValue(
      worksheet.getRow(i).getCell(supplierIdCol).value
    );

    if (value && !validIds.has(value)) {
      errors.push({
        row: i,
        column: "supplier_id",
        message: `Invalid supplier ID: ${value}`,
      });
    }
  }

  return errors;
};

module.exports = { validateSupplierColumn };