const path = require('path');
const { getCalendarWeek } = require('./utils');

function getPdfBaseDir() {
  const configured = process.env.PDF_BASE_DIR && String(process.env.PDF_BASE_DIR).trim();
  if (configured) return path.resolve(configured);
  return path.resolve(path.join(__dirname, '..', 'pdf-cache'));
}

function asciiSafe(value) {
  const s = String(value || '')
    .normalize('NFKD')
    .replace(/[\u0300-\u036f]/g, '');
  return s.replace(/[^A-Za-z0-9_-]+/g, '_').replace(/_+/g, '_').replace(/^_+|_+$/g, '');
}

function getYearFromDate(dateStr) {
  const d = new Date(dateStr);
  const year = d.getFullYear();
  return Number.isFinite(year) ? String(year) : 'unknown-year';
}

function buildTimesheetPdfLocation(timesheetRow) {
  if (!timesheetRow) throw new Error('timesheetRow is required');
  const baseDir = getPdfBaseDir();

  const userId = timesheetRow.user_id;
  const year = getYearFromDate(timesheetRow.week_start);
  const kw = getCalendarWeek(timesheetRow.week_start);
  const version = timesheetRow.version || 1;

  const first = asciiSafe(timesheetRow.firstname || '');
  const last = asciiSafe(timesheetRow.lastname || '');
  const namePart = [last, first].filter(Boolean).join('_') || `user_${userId}`;

  const filename = `${namePart}_timesheet_${timesheetRow.id}_v${version}_KW${String(kw).padStart(2, '0')}_${year}.pdf`;
  const relativePath = path.join(year, String(userId), filename);
  const absolutePath = path.join(baseDir, relativePath);

  return {
    baseDir,
    year,
    kw,
    filename,
    relativePath,
    absolutePath,
    directory: path.dirname(absolutePath),
  };
}

module.exports = {
  getPdfBaseDir,
  buildTimesheetPdfLocation,
};