import "package:flutter/widgets.dart";
import "package:flutter_test/flutter_test.dart";
import "package:garage_ui/garage_ui.dart";

import "support/test_scheme.dart";

// A segmented control lives in a PropertyRow: bounded WIDTH, unbounded height.
// That combination is the whole point of these tests - `expands: true` drops
// the IntrinsicHeight that gives `stretch` something to stretch to, and the
// buttons collapse to nothing.
Widget _host(Widget child) => Directionality(
      textDirection: TextDirection.ltr,
      child: GarageTheme(
        data: ThemeData(colorScheme: testScheme, density: const Density()),
        child: Align(
          alignment: Alignment.topLeft,
          child: SizedBox(width: 300, child: child),
        ),
      ),
    );

Widget _seg(String label) => Button(
      style: const ButtonStyle.outline(),
      alignment: Alignment.center,
      onPressed: () {},
      child: Text(label),
    );

void main() {
  testWidgets("fill splits the main axis evenly", (tester) async {
    await tester.pumpWidget(
      _host(
        ButtonGroup.horizontal(
          fill: true,
          children: [_seg("Off"), _seg("Optional"), _seg("Required")],
        ),
      ),
    );

    expect(tester.takeException(), isNull);

    final off = tester.getSize(find.widgetWithText(Button, "Off"));
    final optional = tester.getSize(find.widgetWithText(Button, "Optional"));
    final required = tester.getSize(find.widgetWithText(Button, "Required"));

    // an even share of the 300, not a share of the label lengths
    expect(off.width, closeTo(100, 1));
    expect(optional.width, closeTo(100, 1));
    expect(required.width, closeTo(100, 1));

    // and a real height, which is what collapsed before
    expect(off.height, greaterThan(0));
  });

  testWidgets("it survives a narrow field without overflowing", (
    tester,
  ) async {
    // a phone-width property row. Three segments that each want ~90px of
    // label in 200px is where a fill would blow the right edge off.
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: GarageTheme(
          data: ThemeData(colorScheme: testScheme, density: const Density()),
          child: Align(
            alignment: Alignment.topLeft,
            child: SizedBox(
              width: 200,
              child: ButtonGroup.horizontal(
                fill: true,
                children: [_seg("Off"), _seg("Optional"), _seg("Required")],
              ),
            ),
          ),
        ),
      ),
    );

    expect(tester.takeException(), isNull);
    final group = tester.getSize(find.byType(ButtonGroup));
    expect(group.width, closeTo(200, 1));
    for (final label in ["Off", "Optional", "Required"]) {
      final seg = tester.getSize(find.widgetWithText(Button, label));
      expect(seg.width, closeTo(200 / 3, 1), reason: label);
      expect(seg.height, greaterThan(0), reason: label);
    }
  });

  testWidgets("without fill it still shrink wraps to its labels", (
    tester,
  ) async {
    await tester.pumpWidget(
      _host(
        ButtonGroup.horizontal(
          children: [_seg("Off"), _seg("Optional"), _seg("Required")],
        ),
      ),
    );

    expect(tester.takeException(), isNull);
    final off = tester.getSize(find.widgetWithText(Button, "Off"));
    final required = tester.getSize(find.widgetWithText(Button, "Required"));
    expect(off.width, lessThan(required.width));
  });
}