import 'dart:async';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:url_launcher/url_launcher.dart';

import '../../../core/navigation/broker_navigation.dart';
import '../../../data/models/home/activity_banner.dart';

/// 底部 Tab 根路由 — 点击 banner 跳转这些路径时用 go() 切换 tab
const _tabRoutes = {'/','market', '/market', '/futures', '/copy-trading', '/asset'};

/// 首页 Banner 轮播 — 从接口获取图片，支持 internal/external 跳转
class ActivityCarousel extends ConsumerStatefulWidget {
  const ActivityCarousel({super.key, required this.banners});

  final List<ActivityBanner> banners;

  @override
  ConsumerState<ActivityCarousel> createState() => _ActivityCarouselState();
}

class _ActivityCarouselState extends ConsumerState<ActivityCarousel> {
  final _controller = PageController();
  int _currentPage = 0;
  Timer? _timer;

  @override
  void initState() {
    super.initState();
    _startAutoPlay();
  }

  @override
  void didUpdateWidget(covariant ActivityCarousel old) {
    super.didUpdateWidget(old);
    if (old.banners.length != widget.banners.length) {
      _timer?.cancel();
      _currentPage = 0;
      _startAutoPlay();
    }
  }

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

  void _startAutoPlay() {
    if (widget.banners.length <= 1) return;
    _timer = Timer.periodic(const Duration(seconds: 4), (_) {
      if (!mounted) return;
      final next = (_currentPage + 1) % widget.banners.length;
      _controller.animateToPage(
        next,
        duration: const Duration(milliseconds: 350),
        curve: Curves.easeInOut,
      );
    });
  }

  Future<void> _onTap(ActivityBanner banner) async {
    if (banner.linkUrl.isEmpty) return;
    if (banner.isExternal) {
      launchUrl(Uri.parse(banner.linkUrl), mode: LaunchMode.externalApplication);
      return;
    }

    final url = banner.linkUrl;

    // ── 经纪商页需要先验证身份 ────────────────────────────
    if (url == '/broker' || url.startsWith('/broker')) {
      await openBrokerEntry(context, ref);
      return;
    }

    // ── Tab 级路由用 go() 切换底部导航选中项 ──────────────
    if (!mounted) return;
    final isTabRoute = _tabRoutes.any((r) => url == r || url.startsWith('$r/'));
    if (isTabRoute) {
      context.go(url);
    } else {
      context.push(url);
    }
  }

  @override
  Widget build(BuildContext context) {
    if (widget.banners.isEmpty) return const SizedBox.shrink();

    final cs = Theme.of(context).colorScheme;
    final count = widget.banners.length;

    return Padding(
      padding: const EdgeInsets.fromLTRB(16, 4, 16, 12),
      child: Column(
        children: [
          ClipRRect(
            borderRadius: BorderRadius.circular(14),
            child: SizedBox(
              height: 120,
              child: PageView.builder(
                controller: _controller,
                onPageChanged: (i) => setState(() => _currentPage = i),
                itemCount: count,
                itemBuilder: (context, index) {
                  final banner = widget.banners[index];
                  return GestureDetector(
                    onTap: () => _onTap(banner),
                    child: banner.imageUrl.isNotEmpty
                        ? CachedNetworkImage(
                            imageUrl: banner.imageUrl,
                            fit: BoxFit.cover,
                            width: double.infinity,
                            placeholder: (_, __) => Container(
                              color: cs.surface,
                              child: Center(
                                child: Icon(
                                  Icons.image_outlined,
                                  color: cs.onSurface.withAlpha(60),
                                  size: 32,
                                ),
                              ),
                            ),
                            errorWidget: (_, __, ___) => Container(
                              color: cs.surface,
                              child: Center(
                                child: Column(
                                  mainAxisSize: MainAxisSize.min,
                                  children: [
                                    Icon(Icons.broken_image_outlined,
                                        color: cs.onSurface.withAlpha(80),
                                        size: 28),
                                    const SizedBox(height: 4),
                                    Text(
                                      banner.title,
                                      style: TextStyle(
                                        color: cs.onSurface.withAlpha(120),
                                        fontSize: 12,
                                      ),
                                    ),
                                  ],
                                ),
                              ),
                            ),
                          )
                        : Container(
                            color: cs.surface,
                            child: Center(
                              child: Text(
                                banner.title,
                                style: TextStyle(
                                  color: cs.onSurface,
                                  fontSize: 15,
                                  fontWeight: FontWeight.w600,
                                ),
                              ),
                            ),
                          ),
                  );
                },
              ),
            ),
          ),
          if (count > 1) ...[
            const SizedBox(height: 8),
            // 圆点指示器
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: List.generate(count, (i) {
                final active = i == _currentPage;
                return Container(
                  width: active ? 16 : 6,
                  height: 6,
                  margin: const EdgeInsets.symmetric(horizontal: 2),
                  decoration: BoxDecoration(
                    color: active
                        ? cs.onSurface
                        : cs.onSurface.withAlpha(60),
                    borderRadius: BorderRadius.circular(3),
                  ),
                );
              }),
            ),
          ],
        ],
      ),
    );
  }
}