Casha/lib/features/onboarding/widgets/fade_slide_in.dart

import 'package:flutter/material.dart';

class FadeSlideIn extends StatefulWidget {
  final bool active;
  final Duration delay;
  final Duration duration;
  final Widget child;

  const FadeSlideIn({
    required this.active,
    required this.child,
    this.delay = Duration.zero,
    this.duration = const Duration(milliseconds: 500),
    super.key,
  });

  @override
  State<FadeSlideIn> createState() => _FadeSlideInState();
}

class _FadeSlideInState extends State<FadeSlideIn>
    with SingleTickerProviderStateMixin {
  late final AnimationController _controller;
  late final Animation<double> _opacity;
  late final Animation<Offset> _offset;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      vsync: this,
      duration: widget.duration,
    );
    _opacity = Tween<double>(begin: 0.0, end: 1.0).animate(
      CurvedAnimation(parent: _controller, curve: Curves.easeOut),
    );
    _offset = Tween<Offset>(
      begin: const Offset(0, 0.15),
      end: Offset.zero,
    ).animate(CurvedAnimation(parent: _controller, curve: Curves.easeOut));
  }

  @override
  void didUpdateWidget(covariant FadeSlideIn oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (widget.active && !oldWidget.active) {
      _controller.reset();
      Future.delayed(widget.delay, () {
        if (mounted) _controller.forward();
      });
    } else if (!widget.active && oldWidget.active) {
      _controller.reset();
    }
  }

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _controller,
      builder: (context, child) {
        return Opacity(
          opacity: _opacity.value,
          child: FractionalTranslation(
            translation: _offset.value,
            child: child,
          ),
        );
      },
      child: widget.child,
    );
  }
}