import 'package:flutter/material.dart';

import '../tokens.dart';

/// Dark pill toast, matching the prototype's transient confirmations.
class DmToast {
  DmToast._();

  static OverlayEntry? _entry;

  static void show(BuildContext context, String message) {
    final overlay = Overlay.maybeOf(context);
    if (overlay == null) return;

    _entry?.remove();
    final entry = OverlayEntry(
      builder: (context) => _ToastBody(message: message),
    );
    _entry = entry;
    overlay.insert(entry);

    Future<void>.delayed(const Duration(milliseconds: 2400), () {
      if (_entry == entry) {
        entry.remove();
        _entry = null;
      }
    });
  }

  /// Called when the app is torn down in tests.
  static void dismiss() {
    _entry?.remove();
    _entry = null;
  }
}

class _ToastBody extends StatefulWidget {
  const _ToastBody({required this.message});
  final String message;

  @override
  State<_ToastBody> createState() => _ToastBodyState();
}

class _ToastBodyState extends State<_ToastBody>
    with SingleTickerProviderStateMixin {
  late final AnimationController _c = AnimationController(
    vsync: this,
    duration: const Duration(milliseconds: 240),
  )..forward();

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

  @override
  Widget build(BuildContext context) {
    final bottom = MediaQuery.of(context).viewInsets.bottom;
    return Positioned(
      left: 20,
      right: 20,
      bottom: 96 + bottom,
      child: FadeTransition(
        opacity: _c,
        child: SlideTransition(
          position: Tween(
            begin: const Offset(0, 0.3),
            end: Offset.zero,
          ).animate(CurvedAnimation(parent: _c, curve: Curves.easeOutCubic)),
          child: Center(
            child: Material(
              color: Colors.transparent,
              child: Container(
                padding: const EdgeInsets.symmetric(
                  horizontal: 18,
                  vertical: 11,
                ),
                decoration: BoxDecoration(
                  color: const Color(0xF0191716),
                  borderRadius: DmRadius.all(DmRadius.sm),
                ),
                child: Text(
                  widget.message,
                  textAlign: TextAlign.center,
                  style: DmText.label.copyWith(
                    fontSize: 13.5,
                    color: Colors.white,
                  ),
                ),
              ),
            ),
          ),
        ),
      ),
    );
  }
}

/// Bottom sheet with the prototype's grip, radius and padding.
Future<T?> showDmSheet<T>({
  required BuildContext context,
  required WidgetBuilder builder,
  bool isScrollControlled = true,
}) {
  return showModalBottomSheet<T>(
    context: context,
    isScrollControlled: isScrollControlled,
    backgroundColor: DmColors.canvas,
    barrierColor: DmColors.scrim,
    elevation: 0,
    shape: const RoundedRectangleBorder(
      borderRadius: BorderRadius.vertical(top: Radius.circular(DmRadius.xl)),
    ),
    clipBehavior: Clip.antiAlias,
    builder: (context) => Padding(
      padding: EdgeInsets.only(
        bottom: MediaQuery.of(context).viewInsets.bottom,
      ),
      child: SafeArea(
        top: false,
        child: ConstrainedBox(
          constraints: BoxConstraints(
            maxHeight: MediaQuery.of(context).size.height * 0.86,
          ),
          child: Padding(
            padding: const EdgeInsets.fromLTRB(
              DmSpace.pad,
              10,
              DmSpace.pad,
              20,
            ),
            child: Column(
              mainAxisSize: MainAxisSize.min,
              crossAxisAlignment: CrossAxisAlignment.stretch,
              children: [
                const _SheetGrip(),
                Flexible(child: builder(context)),
              ],
            ),
          ),
        ),
      ),
    ),
  );
}

class _SheetGrip extends StatelessWidget {
  const _SheetGrip();

  @override
  Widget build(BuildContext context) {
    return Container(
      width: 36,
      height: 4,
      margin: const EdgeInsets.only(top: 2, bottom: 18),
      decoration: BoxDecoration(
        color: DmColors.border,
        borderRadius: DmRadius.all(2),
      ),
    );
  }
}

/// Sheet heading + supporting line.
class DmSheetHeader extends StatelessWidget {
  const DmSheetHeader({super.key, required this.title, this.subtitle});

  final String title;
  final String? subtitle;

  @override
  Widget build(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(title, style: DmText.sheetTitle),
        if (subtitle != null) ...[
          const SizedBox(height: 3),
          Text(subtitle!, style: DmText.tiny),
        ],
        const SizedBox(height: 18),
      ],
    );
  }
}