import 'package:flame/components.dart';
import 'package:flame_lua_runtime/runtime/display/runtime_viewport.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  group('RuntimeViewport', () {
    test('fits design size inside screen with letterboxing', () {
      final transform = RuntimeViewport.compute(
        screenSize: Vector2(1280, 720),
        config: const RuntimeViewportConfig(
          designWidth: 720,
          designHeight: 720,
        ),
      );

      expect(transform.x, 280);
      expect(transform.y, 0);
      expect(transform.width, 720);
      expect(transform.height, 720);
      expect(transform.scaleX, 1);
      expect(transform.scaleY, 1);
    });

    test('fills screen by preserving aspect ratio and cropping', () {
      final transform = RuntimeViewport.compute(
        screenSize: Vector2(1280, 720),
        config: const RuntimeViewportConfig(
          designWidth: 720,
          designHeight: 720,
          scaleMode: RuntimeScaleMode.fill,
        ),
      );

      expect(transform.x, 0);
      expect(transform.y, -280);
      expect(transform.width, 1280);
      expect(transform.height, 1280);
      expect(transform.scaleX, closeTo(1.777777, 0.00001));
      expect(transform.scaleY, closeTo(1.777777, 0.00001));
    });

    test('stretches design independently on both axes', () {
      final transform = RuntimeViewport.compute(
        screenSize: Vector2(1440, 720),
        config: const RuntimeViewportConfig(
          designWidth: 720,
          designHeight: 720,
          scaleMode: RuntimeScaleMode.stretch,
        ),
      );

      expect(transform.x, 0);
      expect(transform.y, 0);
      expect(transform.width, 1440);
      expect(transform.height, 720);
      expect(transform.scaleX, 2);
      expect(transform.scaleY, 1);
    });

    test('centers design without scaling', () {
      final transform = RuntimeViewport.compute(
        screenSize: Vector2(1000, 800),
        config: const RuntimeViewportConfig(
          designWidth: 720,
          designHeight: 720,
          scaleMode: RuntimeScaleMode.none,
        ),
      );

      expect(transform.x, 140);
      expect(transform.y, 40);
      expect(transform.width, 720);
      expect(transform.height, 720);
      expect(transform.scaleX, 1);
      expect(transform.scaleY, 1);
    });

    test('applies transform to root component', () {
      final root = PositionComponent();
      RuntimeViewport.apply(
        root,
        const RuntimeViewportTransform(
          x: 10,
          y: 20,
          width: 300,
          height: 400,
          scaleX: 2,
          scaleY: 3,
          scaleMode: RuntimeScaleMode.stretch,
        ),
      );

      expect(root.position, Vector2(10, 20));
      expect(root.size, Vector2(300, 400));
      expect(root.scale, Vector2(2, 3));
    });
  });
}