import 'dart:async';

import 'package:flutter/material.dart';
import 'package:kiwi/kiwi.dart';
import 'package:logging/logging.dart';
import 'package:nc_photos/app_localizations.dart';
import 'package:nc_photos/changelog.dart' as changelog;
import 'package:nc_photos/di_container.dart';
import 'package:nc_photos/k.dart' as k;
import 'package:nc_photos/mobile/android/activity.dart';
import 'package:nc_photos/platform/k.dart' as platform_k;
import 'package:nc_photos/pref.dart';
import 'package:nc_photos/snack_bar_manager.dart';
import 'package:nc_photos/theme.dart';
import 'package:nc_photos/use_case/compat/v29.dart';
import 'package:nc_photos/use_case/compat/v37.dart';
import 'package:nc_photos/use_case/db_compat/v5.dart';
import 'package:nc_photos/widget/home.dart';
import 'package:nc_photos/widget/processing_dialog.dart';
import 'package:nc_photos/widget/setup.dart';
import 'package:nc_photos/widget/sign_in.dart';

class Splash extends StatefulWidget {
  static const routeName = "/splash";

  const Splash({
    Key? key,
  }) : super(key: key);

  @override
  createState() => _SplashState();
}

class _SplashState extends State<Splash> {
  @override
  initState() {
    super.initState();
    WidgetsBinding.instance!.addPostFrameCallback((_) {
      _doWork();
    });
  }

  Future<void> _doWork() async {
    if (Pref().getFirstRunTime() == null) {
      await Pref().setFirstRunTime(DateTime.now().millisecondsSinceEpoch);
    }
    if (_shouldUpgrade()) {
      await _handleUpgrade();
    }
    await _migrateDb();
    _initTimedExit();
  }

  @override
  build(BuildContext context) {
    return AppTheme(
      child: Scaffold(
        body: Builder(builder: (context) => _buildContent(context)),
      ),
    );
  }

  Widget _buildContent(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 16),
      child: Center(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.center,
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(
              Icons.cloud,
              size: 96,
              color: Theme.of(context).colorScheme.primary,
            ),
            const SizedBox(height: 8),
            Text(
              L10n.global().appTitle,
              textAlign: TextAlign.center,
              style: Theme.of(context).textTheme.headline4,
            )
          ],
        ),
      ),
    );
  }

  Future<void> _initTimedExit() async {
    await Future.delayed(const Duration(seconds: 1));
    final account = Pref().getCurrentAccount();
    if (isNeedSetup()) {
      Navigator.pushReplacementNamed(context, Setup.routeName);
    } else if (account == null) {
      Navigator.pushReplacementNamed(context, SignIn.routeName);
    } else {
      Navigator.pushReplacementNamed(context, Home.routeName,
          arguments: HomeArguments(account));
      if (platform_k.isAndroid) {
        final initialRoute = await Activity.consumeInitialRoute();
        if (initialRoute != null) {
          Navigator.pushNamed(context, initialRoute);
        }
      }
    }
  }

  bool _shouldUpgrade() {
    final lastVersion = Pref().getLastVersionOr(k.version);
    return lastVersion < k.version;
  }

  Future<void> _handleUpgrade() async {
    try {
      final lastVersion = Pref().getLastVersionOr(k.version);
      await _upgrade(lastVersion);

      final change = _gatherChangelog(lastVersion);
      if (change.isNotEmpty) {
        await showDialog(
          context: context,
          builder: (context) => AlertDialog(
            title: Text(L10n.global().changelogTitle),
            content: SingleChildScrollView(
              child: Text(
                change,
                style: const TextStyle(fontSize: 14),
              ),
            ),
            actions: <Widget>[
              TextButton(
                onPressed: () {
                  Navigator.of(context).pop();
                },
                child: Text(MaterialLocalizations.of(context).okButtonLabel),
              )
            ],
          ),
        );
      }
    } catch (e, stackTrace) {
      _log.shout("[_handleUpgrade] Failed while upgrade", e, stackTrace);
    } finally {
      await Pref().setLastVersion(k.version);
    }
  }

  Future<void> _upgrade(int lastVersion) async {
    bool isShowDialog = false;
    void showUpdateDialog() {
      if (!isShowDialog) {
        isShowDialog = true;
        showDialog(
          context: context,
          builder: (_) => ProcessingDialog(
            text: L10n.global().genericProcessingDialogContent,
          ),
        );
      }
    }

    if (lastVersion < 290) {
      showUpdateDialog();
      await _upgrade29(lastVersion);
    }
    if (lastVersion < 370) {
      showUpdateDialog();
      await _upgrade37(lastVersion);
    }
    if (isShowDialog) {
      Navigator.of(context).pop();
    }
  }

  Future<void> _upgrade29(int lastVersion) async {
    try {
      _log.info("[_upgrade29] clearDefaultCache");
      await CompatV29.clearDefaultCache();
    } catch (e, stackTrace) {
      _log.shout("[_upgrade29] Failed while clearDefaultCache", e, stackTrace);
      // just leave the cache then
    }
  }

  Future<void> _upgrade37(int lastVersion) async {
    final c = KiwiContainer().resolve<DiContainer>();
    return CompatV37.setAppDbMigrationFlag(c.appDb);
  }

  Future<void> _migrateDb() async {
    bool isShowDialog = false;
    void showUpdateDialog() {
      if (!isShowDialog) {
        isShowDialog = true;
        showDialog(
          context: context,
          builder: (_) => ProcessingDialog(
            text: L10n.global().migrateDatabaseProcessingNotification,
          ),
        );
      }
    }

    final c = KiwiContainer().resolve<DiContainer>();
    if (await DbCompatV5.isNeedMigration(c.appDb)) {
      showUpdateDialog();
      try {
        await DbCompatV5.migrate(c.appDb);
      } catch (_) {
        SnackBarManager().showSnackBar(SnackBar(
          content: Text(L10n.global().migrateDatabaseFailureNotification),
          duration: k.snackBarDurationNormal,
        ));
      }
    }
    if (await CompatV37.isAppDbNeedMigration(c.appDb)) {
      showUpdateDialog();
      try {
        await CompatV37.migrateAppDb(c.appDb);
      } catch (_) {
        SnackBarManager().showSnackBar(SnackBar(
          content: Text(L10n.global().migrateDatabaseFailureNotification),
          duration: k.snackBarDurationNormal,
        ));
      }
    }
    if (isShowDialog) {
      Navigator.of(context).pop();
    }
  }

  String _gatherChangelog(int from) {
    if (from < 100) {
      from *= 10;
    }
    final fromMajor = from ~/ 10;
    try {
      return changelog.contents
          .sublist(fromMajor)
          .reversed
          .whereType<String>()
          .map((e) => e.trim())
          .join("\n\n");
    } catch (e, stacktrace) {
      _log.severe("[_gatherChangelog] Failed", e, stacktrace);
      return "";
    }
  }

  static final _log = Logger("widget.splash._SplashState");
}