import 'package:flutter/material.dart';

import '../utils/app_update_util.dart';
import '../utils/navigation.dart';
import '../viewmodels/update_progress_view_model.dart';
import '../l10n/app_localizations.dart';
import '../l10n/app_localizations_helpers.dart';

class UpdateProgressView extends StatefulWidget {
  final UpdateInfo update;
  final bool simulate;
  final bool simulateError;

  const UpdateProgressView({
    super.key,
    required this.update,
    this.simulate = false,
    this.simulateError = false,
  });

  @override
  State<UpdateProgressView> createState() => _UpdateProgressViewState();
}

class _UpdateProgressViewState extends State<UpdateProgressView> {
  late final UpdateProgressViewModel _vm;

  @override
  void initState() {
    super.initState();
    _vm = UpdateProgressViewModel(
      update: widget.update,
      simulate: widget.simulate,
      simulateError: widget.simulateError,
    );
    _vm.addListener(_onVmChange);
    _vm.start();
  }

  void _onVmChange() {
    if (!mounted) return;

    if (_vm.phase == OtaPhase.done) {
      _showRestartDialog();
    } else if (_vm.phase == OtaPhase.error) {
      _showErrorSnackBar();
    }
  }

  void _showRestartDialog() {
    final l10n = AppLocalizations.of(context);

    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (context) => AlertDialog(
        title: Text(l10n.updateReady),
        content: Text(l10n.updateReadyDescription),
        actions: [
          TextButton(
            onPressed: () {
              Navigator.pop(context);
              this.context.popOrGo('/bar');
            },
            child: Text(l10n.later),
          ),
          FilledButton(
            onPressed: () {
              Navigator.pop(context);
            },
            child: Text(l10n.restartApp),
          ),
        ],
      ),
    );
  }

  void _showErrorSnackBar() {
    final l10n = AppLocalizations.of(context);

    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(l10n.updateError(_vm.errorMessage)),
        backgroundColor: Theme.of(context).colorScheme.error,
        action: SnackBarAction(
          label: l10n.retry,
          onPressed: () {
            _vm.cancel();
            _vm.start();
          },
        ),
      ),
    );
  }

  @override
  void dispose() {
    _vm.removeListener(_onVmChange);
    _vm.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);

    return PopScope(
      canPop: false,
      onPopInvokedWithResult: (didPop, result) {
        if (!didPop) _showCancelDialog();
      },
      child: Scaffold(
        appBar: AppBar(
          leading: IconButton(
            icon: const Icon(Icons.close),
            onPressed: () => _showCancelDialog(),
          ),
          title: Text(l10n.updating),
          centerTitle: true,
          automaticallyImplyLeading: false,
        ),
        body: ListenableBuilder(
          listenable: _vm,
          builder: (context, child) {
            return Center(
              child: ConstrainedBox(
                constraints: const BoxConstraints(maxWidth: 480),
                child: Padding(
                  padding: const EdgeInsets.all(32),
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      _buildHeader(),
                      const SizedBox(height: 40),
                      _buildProgress(_vm),
                      const SizedBox(height: 24),
                      _buildStatus(_vm),
                      const Spacer(),
                      _buildVersionInfo(_vm),
                    ],
                  ),
                ),
              ),
            );
          },
        ),
      ),
    );
  }

  Widget _buildHeader() {
    final l10n = AppLocalizations.of(context);

    return Column(
      children: [
        Container(
          padding: const EdgeInsets.all(24),
          decoration: BoxDecoration(
            color: Theme.of(context).colorScheme.primary.withValues(alpha: 0.1),
            shape: BoxShape.circle,
          ),
          child: Icon(
            Icons.system_update_alt_rounded,
            size: 56,
            color: Theme.of(context).colorScheme.primary,
          ),
        ),
        const SizedBox(height: 24),
        Text('KoolTab', style: Theme.of(context).textTheme.headlineMedium),
        const SizedBox(height: 8),
        Text(
          l10n.version(widget.update.version),
          style: Theme.of(context).textTheme.titleMedium?.copyWith(
            color: Theme.of(context).colorScheme.primary,
          ),
        ),
      ],
    );
  }

  Widget _buildProgress(UpdateProgressViewModel vm) {
    final scheme = Theme.of(context).colorScheme;
    final l10n = AppLocalizations.of(context);

    return Column(
      children: [
        SizedBox(
          width: 200,
          height: 200,
          child: Stack(
            alignment: Alignment.center,
            children: [
              SizedBox.expand(
                child: CircularProgressIndicator(
                  value: vm.phase == OtaPhase.installing ? null : vm.progress,
                  strokeWidth: 10,
                  backgroundColor: scheme.primary.withValues(alpha: 0.12),
                  color: vm.phase == OtaPhase.error
                      ? scheme.error
                      : scheme.primary,
                ),
              ),
              Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  if (vm.phase == OtaPhase.error)
                    Icon(
                      Icons.error_outline_rounded,
                      size: 48,
                      color: scheme.error,
                    )
                  else if (vm.phase == OtaPhase.installing)
                    Icon(
                      Icons.settings_rounded,
                      size: 48,
                      color: scheme.primary,
                    )
                  else
                    Text(
                      '${(vm.progress * 100).toStringAsFixed(0)}%',
                      style: Theme.of(context).textTheme.headlineLarge,
                    ),
                  const SizedBox(height: 4),
                  Text(
                    vm.phase == OtaPhase.installing ? l10n.installing : '',
                    style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                      color: scheme.onSurface.withValues(alpha: 0.6),
                    ),
                  ),
                ],
              ),
            ],
          ),
        ),
        const SizedBox(height: 24),
        if (vm.phase == OtaPhase.downloading)
          LinearProgressIndicator(
            value: vm.progress,
            minHeight: 6,
            borderRadius: BorderRadius.circular(999),
          ),
      ],
    );
  }

  Widget _buildStatus(UpdateProgressViewModel vm) {
    final scheme = Theme.of(context).colorScheme;
    final l10n = AppLocalizations.of(context);

    final color = switch (vm.phase) {
      OtaPhase.error => scheme.error,
      OtaPhase.done => Colors.green,
      _ => scheme.onSurface,
    };

    return Text(
      l10n.updateStatus(vm.statusText),
      style: Theme.of(context).textTheme.titleMedium?.copyWith(color: color),
      textAlign: TextAlign.center,
    );
  }

  Widget _buildVersionInfo(UpdateProgressViewModel vm) {
    final l10n = AppLocalizations.of(context);

    return Row(
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        Icon(
          Icons.info_outline_rounded,
          size: 14,
          color: Theme.of(context).colorScheme.onSurface.withValues(alpha: 0.4),
        ),
        const SizedBox(width: 6),
        Text(
          l10n.doNotCloseDuringUpdate,
          style: Theme.of(context).textTheme.bodySmall?.copyWith(
            color: Theme.of(
              context,
            ).colorScheme.onSurface.withValues(alpha: 0.4),
          ),
        ),
      ],
    );
  }

  void _showCancelDialog() {
    final l10n = AppLocalizations.of(context);

    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(l10n.cancelUpdate),
        content: Text(l10n.cancelUpdateDescription),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: Text(l10n.continueUpdate),
          ),
          FilledButton(
            style: FilledButton.styleFrom(
              backgroundColor: Theme.of(context).colorScheme.error,
            ),
            onPressed: () {
              Navigator.pop(context);
              _vm.cancel();
              this.context.popOrGo('/bar');
            },
            child: Text(l10n.cancelUpdateAction),
          ),
        ],
      ),
    );
  }
}