import 'package:flutter/material.dart';
import 'package:miler/views/helpers/constants/Colorconstants.dart';
import 'package:get/get.dart';
import 'package:package_info_plus/package_info_plus.dart';
import 'package:shared_preferences/shared_preferences.dart';

import 'package:miler/controllers/auth.dart';
import 'package:miler/views/introscreens/introscreen.dart';
import 'package:miler/views/onboardscreens/Mpin.dart';
import 'package:miler/views/onboardscreens/Sign_in.dart';
import 'package:miler/widget/Bottom_page.dart';

/// Decides which screen the app opens on, and nothing else.
///
/// This replaces the old animated splash screen. The splash held two very
/// different jobs: a four-second brand animation, and the routing rules that
/// decide login vs. intro vs. home. Only the second one is load-bearing.
///
/// The four seconds were pure cost for a rider who opens this app 30–50 times
/// a shift — the native launch image already covers the cold-start gap, so the
/// animation was time added on top of it, every single time. Removing it is
/// the single biggest latency win on the whole flow.
///
/// What survives is the routing, unchanged in behaviour:
///  • app version changed since last run  → force re-verification (MPIN if the
///    rider was signed in, otherwise Sign In)
///  • signed in + on duty                  → straight to the dashboard
///  • signed in + off duty                 → the go-on-duty banner
///  • signed out, intro already seen       → Sign In
///  • first ever launch                    → Introscreen
class AppBootstrap extends StatefulWidget {
  const AppBootstrap({super.key});

  @override
  State<AppBootstrap> createState() => _AppBootstrapState();
}

class _AppBootstrapState extends State<AppBootstrap> {
  bool _routed = false;

  @override
  void initState() {
    super.initState();
    // Route on the first frame — GetX needs a built navigator before `offAll`.
    WidgetsBinding.instance.addPostFrameCallback((_) => _resolveStartScreen());
  }

  Future<void> _resolveStartScreen() async {
    if (_routed) return;
    _routed = true;

    final prefs = await SharedPreferences.getInstance();
    final bool isLoggedOut = prefs.getBool('logged_out') ?? false;
    final bool hasSeenIntro = prefs.getBool('has_seen_intro') ?? false;
    final int? savedUserId = prefs.getInt('userid');

    // ── App update → force re-verification ──
    try {
      final packageInfo = await PackageInfo.fromPlatform();
      final currentVersion = packageInfo.version;
      final lastRunVersion = prefs.getString('last_run_version');

      if (lastRunVersion != null && lastRunVersion != currentVersion) {
        debugPrint(
          '[BOOTSTRAP] App update detected: $lastRunVersion -> $currentVersion. '
          'Forcing re-verification.',
        );

        final String? savedPhone = prefs.getString('contactno');
        await prefs.setString('last_run_version', currentVersion);

        if (savedUserId != null &&
            savedPhone != null &&
            savedPhone.isNotEmpty) {
          debugPrint(
            '[BOOTSTRAP] User was logged in. Redirecting to MPIN page.',
          );

          final auth = Get.put(AuthController());
          auth.currentPhone = savedPhone;

          await prefs.remove('userid');
          await prefs.remove('partnerid');
          await prefs.remove('onduty');
          await prefs.setBool('logged_out', true);

          if (mounted) Get.offAll(() => Mpin());
          return;
        }

        debugPrint(
          '[BOOTSTRAP] User was not logged in. Redirecting to Sign In.',
        );
        if (mounted) Get.offAll(() => const SignIn());
        return;
      }
      await prefs.setString('last_run_version', currentVersion);
    } catch (e) {
      debugPrint('[BOOTSTRAP] Version check error: $e');
    }

    if (!mounted) return;

    // ── Normal launch ──
    //
    // A signed-in rider lands on the tabs whether or not he is on duty. The
    // duty gate that used to sit here made "open the app" and "start working"
    // the same decision, so a rider checking his earnings between shifts had to
    // pass a slider that put him back on the clock. Duty is a switch in Home's
    // app bar, on the screen where the work is.
    if (!isLoggedOut && savedUserId != null && savedUserId > 0) {
      Get.offAll(() => const BottomPage());
    } else {
      Get.offAll(() => hasSeenIntro ? const SignIn() : Introscreen());
    }
  }

  @override
  Widget build(BuildContext context) {
    // Held for the few milliseconds the prefs read takes. Plain white so it is
    // indistinguishable from the native launch image — the rider should never
    // perceive a screen here at all.
    return Scaffold(
      backgroundColor: ColorConstants.pureSurface,
      body: SizedBox.expand(),
    );
  }
}