import 'package:flutter/services.dart' show rootBundle;
import 'package:pdf/widgets.dart' as pw;

/// Fonts and theme shared by every generated PDF (labels, catalog, recovery
/// sheet). [theme] is the document-wide default; [bold] is exposed for the few
/// places that set a heading weight explicitly — merging against [theme] keeps
/// its script fallbacks, so bold Arabic/CJK still renders.
typedef PdfFonts = ({pw.ThemeData theme, pw.Font bold});

/// Loads the PDF fonts.
///
/// The base face is DejaVu (Latin extended, Cyrillic, Greek) with Noto Arabic
/// and Noto CJK registered as per-glyph fallbacks, so vernacular species names,
/// user notes, and localized labels in Arabic (RTL) or CJK render instead of
/// showing tofu boxes. The `pdf` package subsets fonts to the glyphs actually
/// used, so bundling the full Noto faces does not bloat the output file.
///
/// Fonts are a per-locale resource, extensible to any script — widen the
/// fallback list as more scripts land.
Future<PdfFonts> loadPdfFonts() async {
  final base = pw.Font.ttf(
    await rootBundle.load('assets/fonts/DejaVuSans.ttf'),
  );
  final bold = pw.Font.ttf(
    await rootBundle.load('assets/fonts/DejaVuSans-Bold.ttf'),
  );
  final arabic = pw.Font.ttf(
    await rootBundle.load('assets/fonts/NotoSansArabic.ttf'),
  );
  final cjk = pw.Font.ttf(await rootBundle.load('assets/fonts/NotoSansJP.ttf'));
  final theme = pw.ThemeData.withFont(
    base: base,
    bold: bold,
    italic: base,
    fontFallback: [arabic, cjk],
  );
  return (theme: theme, bold: bold);
}