import 'package:drift/native.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:glp1_companion/core/database/app_database.dart';
import 'package:glp1_companion/features/meal_planner/presentation/screens/meal_planner_screen.dart';

/// Regression tests for the desktop resize overflow (yellow/black hatched
/// stripes): the meal planner must reflow into scrollable layouts at short
/// window heights instead of overflowing a rigid `Column`.
///
/// RenderFlex overflows raise a [FlutterError] inside widget tests, so a
/// clean run also proves the stripes are gone.
void main() {
  late AppDatabase database;

  setUp(() {
    database = AppDatabase.forTesting(NativeDatabase.memory());
  });

  tearDown(() => database.close());

  Future<void> pumpScreen(
    WidgetTester tester, {
    required Size logicalSize,
  }) async {
    tester.view.physicalSize = logicalSize;
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);
    addTearDown(tester.view.resetDevicePixelRatio);

    await tester.pumpWidget(
      ProviderScope(
        overrides: [appDatabaseProvider.overrideWithValue(database)],
        child: const MaterialApp(home: MealPlannerScreen()),
      ),
    );
    // Let the initial drift loads (watch stream + microtask refresh) settle.
    await tester.pump();
    await tester.pump(const Duration(milliseconds: 50));
    await tester.pump(const Duration(milliseconds: 50));
  }

  /// Unmounts the tree and flushes the zero-duration timer drift schedules
  /// when its query streams are cancelled during container disposal
  /// (`StreamQueryStore.markAsClosed`), which would otherwise trip the test
  /// framework's pending-timers invariant.
  Future<void> unmountAndFlushTimers(WidgetTester tester) async {
    await tester.pumpWidget(const SizedBox());
    await tester.pump(const Duration(milliseconds: 1));
  }

  testWidgets(
      'short compact window collapses into a scrollable page without overflow',
      (tester) async {
    await pumpScreen(tester, logicalSize: const Size(480, 400));

    expect(find.byType(MealPlannerScreen), findsOneWidget);
    expect(find.text('Saved Recipes'), findsOneWidget);
    expect(tester.takeException(), isNull);

    // The whole page scrolls: drag upward and verify the content moved up.
    final before = tester.getTopLeft(find.text('Saved Recipes')).dy;
    await tester.drag(find.text('Saved Recipes'), const Offset(0, -200));
    await tester.pump();
    final after = tester.getTopLeft(find.text('Saved Recipes')).dy;

    expect(after, lessThan(before),
        reason: 'the page should scroll vertically when the window is short');
    expect(tester.takeException(), isNull);
    await unmountAndFlushTimers(tester);
  });

  testWidgets(
      'short wide window keeps the 7-day grid with scrollable day columns',
      (tester) async {
    await pumpScreen(tester, logicalSize: const Size(1100, 420));

    // Wide breakpoint: all seven weekday headers render at once.
    for (final label in const [
      'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday',
    ]) {
      expect(find.textContaining(label), findsWidgets);
    }
    expect(tester.takeException(), isNull);

    // The outer page scrolls so the calendar area is reachable when the
    // window is shorter than the fixed top sections + calendar.
    final before = tester.getTopLeft(find.text('Saved Recipes')).dy;
    await tester.drag(find.text('Saved Recipes'), const Offset(0, -200));
    await tester.pump();
    expect(tester.getTopLeft(find.text('Saved Recipes')).dy, lessThan(before));
    expect(tester.takeException(), isNull);
    await unmountAndFlushTimers(tester);
  });

  testWidgets('tall window uses the pinned layout without overflow',
      (tester) async {
    await pumpScreen(tester, logicalSize: const Size(1000, 900));

    expect(find.text('Saved Recipes'), findsOneWidget);
    for (final label in const [
      'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday',
    ]) {
      expect(find.textContaining(label), findsWidgets);
    }
    expect(tester.takeException(), isNull);
    await unmountAndFlushTimers(tester);
  });

  testWidgets('extremely short window still renders without overflow',
      (tester) async {
    await pumpScreen(tester, logicalSize: const Size(1280, 320));

    expect(find.byType(MealPlannerScreen), findsOneWidget);
    expect(tester.takeException(), isNull);
    await unmountAndFlushTimers(tester);
  });
}