01_basic_usage.dart

import 'dart:io';
import 'package:glyph_path/glyph_path.dart';

const String _text = 'Hello Dart';
const double _fontSize = 48.0;

void main(List<String> args) {
  if (args.isEmpty) {
    stderr.writeln(
      'Usage: dart run example/01_basic_usage.dart <font.ttf>\n'
      '  <font.ttf>  Path to a TrueType/OpenType font file.\n'
      '              Free fonts: https://fonts.google.com  (download *.ttf)\n'
      '                          https://notofonts.github.io',
    );
    exit(1);
  }

  final File fontFile = File(args[0]);
  if (!fontFile.existsSync()) {
    stderr.writeln('Error: font not found at ${args[0]}');
    exit(1);
  }

  final Font font = Font.parse(fontFile.readAsBytesSync());

  // --- generateGlyphPaths: iterate PathCommand subtypes ---
  final TextPathResult result = font.generateGlyphPaths(
    _text,
    fontSize: _fontSize,
  );

  final Map<String, int> counts = <String, int>{};
  for (final PathCommand cmd in result.commands) {
    final String type = switch (cmd) {
      MoveTo() => 'MoveTo',
      LineTo() => 'LineTo',
      QuadTo() => 'QuadTo',
      CubicTo() => 'CubicTo',
      ClosePath() => 'ClosePath',
    };
    counts[type] = (counts[type] ?? 0) + 1;
  }

  stdout.writeln('generateGlyphPaths("$_text", fontSize: $_fontSize)');
  stdout.writeln('  total commands : ${result.commands.length}');
  for (final MapEntry<String, int> e in counts.entries) {
    stdout.writeln('  ${e.key.padRight(10)}: ${e.value}');
  }
  stdout.writeln('  unitsPerEm     : ${result.unitsPerEm}');
  stdout.writeln('  ascender       : ${result.ascender}');
  stdout.writeln('  descender      : ${result.descender}');

  // --- measureText: advance width without generating paths ---
  final TextMeasurement advance = font.measureText(_text, fontSize: _fontSize);
  stdout.writeln(
    '\nmeasureText("$_text", fontSize: $_fontSize) → ${advance.width}',
  );
}