import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';

import 'package:fuel_tax_tracker/widgets/onboarding_tour_overlay.dart';

/// Unit-level coverage of the tour's presentational overlay widget,
/// independent of MainShell's step-sequencing/navigation logic (covered
/// in main_shell_test.dart's onboarding-tour group instead).
void main() {
  Widget wrap(Widget child) => MaterialApp(home: Scaffold(body: child));

  testWidgets('shows the title, description, and step count', (tester) async {
    final targetKey = GlobalKey();

    await tester.pumpWidget(wrap(
      OnboardingTourOverlay(
        targetKeys: [targetKey],
        title: 'Example Title',
        description: 'Example description text.',
        stepNumber: 2,
        totalSteps: 4,
        onNext: () {},
        onSkip: () {},
      ),
    ));

    expect(find.text('Example Title'), findsOneWidget);
    expect(find.text('Example description text.'), findsOneWidget);
    expect(find.text('Step 2 of 4'), findsOneWidget);
  });

  testWidgets('shows "Next" before the last step and "Got It" on the last step', (tester) async {
    final targetKey = GlobalKey();

    await tester.pumpWidget(wrap(
      OnboardingTourOverlay(
        targetKeys: [targetKey],
        title: 'T',
        description: 'D',
        stepNumber: 1,
        totalSteps: 3,
        onNext: () {},
        onSkip: () {},
      ),
    ));
    expect(find.widgetWithText(FilledButton, 'Next'), findsOneWidget);
    expect(find.widgetWithText(FilledButton, 'Got It'), findsNothing);

    await tester.pumpWidget(wrap(
      OnboardingTourOverlay(
        targetKeys: [targetKey],
        title: 'T',
        description: 'D',
        stepNumber: 3,
        totalSteps: 3,
        onNext: () {},
        onSkip: () {},
      ),
    ));
    expect(find.widgetWithText(FilledButton, 'Got It'), findsOneWidget);
    expect(find.widgetWithText(FilledButton, 'Next'), findsNothing);
  });

  testWidgets('invokes onNext/onSkip when their buttons are tapped', (tester) async {
    var nextTapped = false;
    var skipTapped = false;
    final targetKey = GlobalKey();

    await tester.pumpWidget(wrap(
      OnboardingTourOverlay(
        targetKeys: [targetKey],
        title: 'T',
        description: 'D',
        stepNumber: 1,
        totalSteps: 2,
        onNext: () => nextTapped = true,
        onSkip: () => skipTapped = true,
      ),
    ));

    await tester.tap(find.widgetWithText(TextButton, 'Skip Tour'));
    expect(skipTapped, isTrue);

    await tester.tap(find.widgetWithText(FilledButton, 'Next'));
    expect(nextTapped, isTrue);
  });

  testWidgets(
      'renders without crashing when the target key has no RenderObject yet — falls back to a '
      'centered card', (tester) async {
    final targetKey = GlobalKey(); // never attached to anything

    await tester.pumpWidget(wrap(
      OnboardingTourOverlay(
        targetKeys: [targetKey],
        title: 'T',
        description: 'D',
        stepNumber: 1,
        totalSteps: 1,
        onNext: () {},
        onSkip: () {},
      ),
    ));

    expect(find.text('T'), findsOneWidget);
  });

  testWidgets('tapping the dimmed barrier does not invoke onNext or onSkip', (tester) async {
    var nextTapped = false;
    var skipTapped = false;
    final targetKey = GlobalKey();

    await tester.pumpWidget(wrap(
      OnboardingTourOverlay(
        targetKeys: [targetKey],
        title: 'T',
        description: 'D',
        stepNumber: 1,
        totalSteps: 1,
        onNext: () => nextTapped = true,
        onSkip: () => skipTapped = true,
      ),
    ));

    // Top-left corner — away from the card, which sits mid/lower-screen.
    await tester.tapAt(const Offset(5, 5));
    await tester.pump();

    expect(nextTapped, isFalse);
    expect(skipTapped, isFalse);
  });

  testWidgets('highlights every key in targetKeys, not just the first', (tester) async {
    final topKey = GlobalKey();
    final bottomKey = GlobalKey();

    Widget buildTree({required bool showOverlay}) => MaterialApp(
          home: Scaffold(
            body: Stack(
              children: [
                Positioned(top: 0, left: 0, child: SizedBox(key: topKey, width: 40, height: 40)),
                Positioned(
                    bottom: 0, left: 0, child: SizedBox(key: bottomKey, width: 40, height: 40)),
                if (showOverlay)
                  OnboardingTourOverlay(
                    targetKeys: [topKey, bottomKey],
                    title: 'Both Highlighted',
                    description: 'D',
                    stepNumber: 1,
                    totalSteps: 1,
                    onNext: () {},
                    onSkip: () {},
                  ),
              ],
            ),
          ),
        );

    // Two frames, matching how MainShell actually uses this: the target
    // keys' RenderBoxes need to already exist and be laid out (from a
    // prior frame) before the overlay's own build() can find their real
    // position — querying them in the very same frame they're first
    // mounted finds nothing yet (layout hasn't run for that frame at
    // build time).
    await tester.pumpWidget(buildTree(showOverlay: false));
    await tester.pumpWidget(buildTree(showOverlay: true));

    // One highlight border per resolved key.
    expect(find.byType(DecoratedBox), findsNWidgets(2));
    expect(find.text('Both Highlighted'), findsOneWidget);
  });

  testWidgets('still renders correctly when only some of targetKeys resolve', (tester) async {
    final resolvedKey = GlobalKey();
    final unresolvedKey = GlobalKey(); // never attached to anything

    Widget buildTree({required bool showOverlay}) => MaterialApp(
          home: Scaffold(
            body: Stack(
              children: [
                SizedBox(key: resolvedKey, width: 40, height: 40),
                if (showOverlay)
                  OnboardingTourOverlay(
                    targetKeys: [resolvedKey, unresolvedKey],
                    title: 'T',
                    description: 'D',
                    stepNumber: 1,
                    totalSteps: 1,
                    onNext: () {},
                    onSkip: () {},
                  ),
              ],
            ),
          ),
        );

    await tester.pumpWidget(buildTree(showOverlay: false));
    await tester.pumpWidget(buildTree(showOverlay: true));

    expect(find.byType(DecoratedBox), findsNWidgets(1), reason: 'only the resolved key gets a border');
    expect(find.text('T'), findsOneWidget);
  });
}