import 'package:flutter/material.dart';

import 'app_controller.dart';
import 'app_theme.dart';
import '../widgets/glass_dock.dart';
import '../features/timetable/timetable_page.dart';
import '../features/profile/profile_page.dart';

class HepanApp extends StatelessWidget {
  const HepanApp({super.key, required this.controller, this.schoolBuilder});
  final AppController controller;
  final Widget Function()? schoolBuilder;
  @override
  Widget build(BuildContext context) => MaterialApp(
    debugShowCheckedModeBanner: false,
    title: '河畔Everyday',
    theme: hepanTheme(),
    home: _Shell(controller: controller, schoolBuilder: schoolBuilder),
  );
}

class _Shell extends StatefulWidget {
  const _Shell({required this.controller, this.schoolBuilder});
  final AppController controller;
  final Widget Function()? schoolBuilder;
  @override
  State<_Shell> createState() => _ShellState();
}

class _ShellState extends State<_Shell> with WidgetsBindingObserver {
  int _tab = 0;
  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      widget.controller.refreshServices();
    }
  }

  void _school() {
    if (widget.schoolBuilder != null) {
      Navigator.push(
        context,
        MaterialPageRoute<void>(builder: (_) => widget.schoolBuilder!()),
      );
    } else {
      showDialog<void>(
        context: context,
        builder: (context) => AlertDialog(
          title: const Text('学校认证'),
          content: const Text('学校认证入口正在接入。你可以先体验示例课表或导入课表文件。'),
          actions: [
            TextButton(
              onPressed: () => Navigator.pop(context),
              child: const Text('知道了'),
            ),
          ],
        ),
      );
    }
  }

  @override
  Widget build(BuildContext context) => AnimatedBuilder(
    animation: widget.controller,
    builder: (context, _) => Scaffold(
      body: Container(
        decoration: const BoxDecoration(
          gradient: LinearGradient(
            begin: Alignment.topLeft,
            end: Alignment.bottomRight,
            colors: [Color(0xFFF0F7F5), Color(0xFFF7F8F5), Color(0xFFEFF5F3)],
          ),
        ),
        child: SafeArea(
          bottom: false,
          child: Stack(
            children: [
              Positioned.fill(
                child: Column(
                  children: [
                    if (widget.controller.lastError != null)
                      Container(
                        width: double.infinity,
                        color: const Color(0xFFF8ECE6),
                        padding: const EdgeInsets.all(12),
                        child: Column(
                          crossAxisAlignment: CrossAxisAlignment.start,
                          children: [
                            Text(
                              widget.controller.lastError!,
                              style: const TextStyle(fontSize: 12),
                            ),
                            if (!widget.controller.storageReady)
                              TextButton(
                                onPressed: widget.controller.restoreBackup,
                                child: const Text('恢复最近备份'),
                              ),
                          ],
                        ),
                      ),
                    Expanded(
                      child: IndexedStack(
                        index: _tab,
                        children: [
                          TimetablePage(controller: widget.controller),
                          ProfilePage(
                            controller: widget.controller,
                            onLogin: _school,
                          ),
                        ],
                      ),
                    ),
                  ],
                ),
              ),
              Positioned(
                left: 0,
                right: 0,
                bottom: 16 + MediaQuery.paddingOf(context).bottom,
                child: Center(
                  child: GlassDock(
                    selectedIndex: _tab,
                    onSelected: (index) => setState(() => _tab = index),
                  ),
                ),
              ),
            ],
          ),
        ),
      ),
    ),
  );
}