// notifications_page.dart — 通知(占位屏)
//
// TODO(spec-3): 列表来自 GET /v1/notices，已读态本地持久化。当前为 3 条静态示例，
// 仅供 IA 走查——接后端前不接任何真实业务逻辑。
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../l10n/app_text.dart';
import '../pangolin_theme.dart';
import '../widgets/pangolin_icons.dart';
import '../widgets/status_pill.dart';

typedef _Notice = ({
  IconData icon,
  PangolinStatus status,
  String typeLabel,
  String title,
  String sub,
  bool read,
});

class NotificationsScreen extends ConsumerWidget {
  const NotificationsScreen({super.key, required this.t, this.onBack, this.embedded = false});
  final AppText t;
  final VoidCallback? onBack;
  final bool embedded;

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final c = context.pangolin;

    // 静态示例数据(占位):News / Feature / Important 各一条,类型 pill 文案走 t.notifType*。
    final notices = <_Notice>[
      (
        icon: PangolinIcons.bell,
        status: PangolinStatus.neutral,
        typeLabel: t.notifTypeNews,
        title: 'Product update', // TODO(spec-3): placeholder
        sub: '2 days ago',
        read: false,
      ),
      (
        icon: PangolinIcons.zap,
        status: PangolinStatus.connected,
        typeLabel: t.notifTypeFeature,
        title: 'New feature released', // TODO(spec-3): placeholder
        sub: '5 days ago',
        read: false,
      ),
      (
        icon: PangolinIcons.alertTriangle,
        status: PangolinStatus.error,
        typeLabel: t.notifTypeImportant,
        title: 'Important notice', // TODO(spec-3): placeholder
        sub: '1 week ago',
        read: true,
      ),
    ];

    Widget empty() => Padding(
          padding: const EdgeInsets.only(top: 60),
          child: Column(children: [
            Container(
              width: 56,
              height: 56,
              decoration: BoxDecoration(color: c.bgSubtle, shape: BoxShape.circle),
              child: Icon(PangolinIcons.bell, size: 26, color: c.fg3),
            ),
            const SizedBox(height: 14),
            Text(t.notifEmpty, style: PangolinText.sm.copyWith(color: c.fg3)),
          ]),
        );

    Widget row(_Notice n, bool divider) {
      return Container(
        decoration: BoxDecoration(border: divider ? Border(bottom: BorderSide(color: c.border)) : null),
        padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 13),
        child: Row(crossAxisAlignment: CrossAxisAlignment.start, children: [
          Stack(clipBehavior: Clip.none, children: [
            Container(
              width: 38,
              height: 38,
              decoration: BoxDecoration(color: c.accentSubtle, borderRadius: BorderRadius.circular(PangolinRadius.md)),
              child: Icon(n.icon, size: 18, color: c.accent),
            ),
            if (!n.read)
              Positioned(
                top: -2,
                right: -2,
                child: Container(
                  width: 8,
                  height: 8,
                  decoration: BoxDecoration(color: c.danger, shape: BoxShape.circle),
                ),
              ),
          ]),
          const SizedBox(width: 12),
          Expanded(
            child: Column(crossAxisAlignment: CrossAxisAlignment.start, mainAxisSize: MainAxisSize.min, children: [
              Row(children: [
                Expanded(
                  child: Text(n.title,
                      overflow: TextOverflow.ellipsis,
                      style: PangolinText.sm.copyWith(
                          color: c.fg1, fontWeight: n.read ? FontWeight.w500 : FontWeight.w700, fontSize: 14.5)),
                ),
                const SizedBox(width: 8),
                StatusPill(label: n.typeLabel, status: n.status),
              ]),
              const SizedBox(height: 4),
              Text(n.sub, style: PangolinText.caption.copyWith(color: c.fg3, fontWeight: FontWeight.w400)),
            ]),
          ),
        ]),
      );
    }

    Widget content() => ListView(
          padding: const EdgeInsets.fromLTRB(20, 8, 20, 24),
          children: [
            if (notices.isEmpty)
              empty()
            else
              Container(
                decoration: BoxDecoration(
                  color: c.surface,
                  borderRadius: BorderRadius.circular(PangolinRadius.lg),
                  border: Border.all(color: c.border),
                  boxShadow: PangolinShadow.sm,
                ),
                clipBehavior: Clip.antiAlias,
                child: Column(children: [
                  for (var i = 0; i < notices.length; i++) row(notices[i], i < notices.length - 1),
                ]),
              ),
          ],
        );

    if (embedded) return content();
    return Scaffold(
      backgroundColor: c.bg,
      body: SafeArea(
        child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
          Padding(
            padding: const EdgeInsets.fromLTRB(8, 6, 16, 10),
            child: Row(children: [
              IconButton(
                onPressed: onBack ?? () => Navigator.of(context).maybePop(),
                icon: Icon(PangolinIcons.arrowLeft, size: 22, color: c.fg1),
              ),
              Text(t.notifTitle, style: PangolinText.h3.copyWith(color: c.fg1, fontWeight: FontWeight.w700)),
            ]),
          ),
          Expanded(child: content()),
        ]),
      ),
    );
  }
}