// Renders the progress bar in the states an operator actually meets
// and writes PNGs to build/progress/, so the visual result can be
// judged without launching the desktop app and stealing focus.
//
// Not a golden comparison: there is no committed reference to diff
// against. It exists to produce evidence, and to guard that every one
// of these states renders at all in both themes.

import 'dart:io';
import 'dart:ui' as ui;

import 'package:chain_studio/theme/theme.dart';
import 'package:chain_studio/widgets/chain_progress_bar.dart';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter_test/flutter_test.dart';

class _Case {
  final String label;
  final Widget bar;
  const _Case(this.label, this.bar);
}

const _cases = <_Case>[
  _Case(
    'Nichts messbar: unbestimmt statt leer',
    ChainProgressBar(stage: 'Modul wird gesucht'),
  ),
  _Case(
    'Download mit Groesse',
    ChainProgressBar(
      value: 0.42,
      stage: 'Wird heruntergeladen',
      detail: '5,0 von 12,0 MB',
    ),
  ),
  _Case(
    'Wert steht, Arbeit laeuft weiter',
    ChainProgressBar(value: 0.74, stage: 'Wird geprueft und entpackt'),
  ),
  _Case(
    'Fertig: nichts bewegt sich mehr',
    ChainProgressBar(value: 1.0, busy: false, stage: 'Fertig'),
  ),
];

Widget _sheet(ThemeData theme, String title) => MaterialApp(
  theme: theme,
  debugShowCheckedModeBanner: false,
  home: Scaffold(
    body: RepaintBoundary(
      key: const ValueKey('sheet'),
      child: Center(
        child: SizedBox(
          width: 520,
          child: Card(
            margin: const EdgeInsets.all(24),
            child: Padding(
              padding: const EdgeInsets.all(24),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.stretch,
                mainAxisSize: MainAxisSize.min,
                children: [
                  Text(title, style: theme.textTheme.titleMedium),
                  const SizedBox(height: 20),
                  for (final c in _cases) ...[
                    Text(c.label, style: theme.textTheme.labelSmall),
                    const SizedBox(height: 6),
                    c.bar,
                    const SizedBox(height: 22),
                  ],
                ],
              ),
            ),
          ),
        ),
      ),
    ),
  ),
);

Future<void> _capture(WidgetTester tester, String name) async {
  final boundary = tester.renderObject<RenderRepaintBoundary>(
    find.byKey(const ValueKey('sheet')),
  );
  // toImage is real asynchronous engine work. Awaiting it directly in a
  // widget test leaves the binding waiting forever afterwards, which
  // showed up as this file passing in six seconds and then sitting
  // there until the ten-minute timeout killed the whole suite.
  final image = await tester.runAsync(() => boundary.toImage(pixelRatio: 2));
  if (image == null) return;
  final bytes = await tester.runAsync(
    () => image.toByteData(format: ui.ImageByteFormat.png),
  );
  final dir = Directory('build/progress')..createSync(recursive: true);
  File('${dir.path}/$name.png').writeAsBytesSync(bytes!.buffer.asUint8List());
}

void main() {
  // One capture per run: a second toImage() in the same test binding
  // never completes, so the theme comes from the environment and the
  // sheet is rendered twice from outside:
  //
  //   flutter test test/progress_bar_visual_test.dart
  //   PROGRESS_THEME=dark flutter test test/progress_bar_visual_test.dart
  testWidgets('renders every waiting state', (tester) async {
    final dark = Platform.environment['PROGRESS_THEME'] == 'dark';
    tester.view.physicalSize = const Size(1100, 900);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.reset);

    await tester.pumpWidget(
      _sheet(
        dark ? ChainTheme.dark() : ChainTheme.light(),
        dark ? 'Dunkel' : 'Hell',
      ),
    );
    // Mid-sweep, so the highlight sits inside the bar in the capture.
    await tester.pump(const Duration(milliseconds: 900));
    expect(find.byType(ChainProgressBar), findsNWidgets(_cases.length));
    await _capture(tester, dark ? 'states-dark' : 'states-light');
    await tester.pumpWidget(const SizedBox());
  });
}