import 'package:abawo_bt_app/model/firmware_file_selection.dart';
import 'package:abawo_bt_app/model/shifter_types.dart';
import 'package:flutter/material.dart';

class FirmwareUpdateFullscreen extends StatelessWidget {
  const FirmwareUpdateFullscreen({
    super.key,
    required this.progress,
    required this.selectedFirmware,
    required this.phaseText,
    required this.statusText,
    required this.formattedProgressBytes,
    required this.expectedOffsetHex,
    required this.onDismiss,
    this.doneLabel = 'Done',
    this.failedLabel = 'Back to device',
  });

  final DfuUpdateProgress progress;
  final BootloaderDfuPreparedFirmware? selectedFirmware;
  final String phaseText;
  final String? statusText;
  final String formattedProgressBytes;
  final String expectedOffsetHex;
  final VoidCallback onDismiss;
  final String doneLabel;
  final String failedLabel;

  bool get _isTerminal =>
      progress.state == DfuUpdateState.completed ||
      progress.state == DfuUpdateState.failed;

  bool get _isRunning => !_isTerminal && progress.state != DfuUpdateState.idle;

  String? get _bootloaderStatusText {
    final status = progress.bootloaderStatus;
    if (status == null) {
      return null;
    }
    final codeLabel = switch (status.code) {
      DfuBootloaderStatusCode.ok => 'OK',
      DfuBootloaderStatusCode.parseError => 'parse error',
      DfuBootloaderStatusCode.stateError => 'state error',
      DfuBootloaderStatusCode.boundsError => 'bounds error',
      DfuBootloaderStatusCode.crcError => 'CRC error',
      DfuBootloaderStatusCode.flashError => 'flash error',
      DfuBootloaderStatusCode.unsupportedError => 'unsupported flags',
      DfuBootloaderStatusCode.vectorError => 'vector table error',
      DfuBootloaderStatusCode.queueFull => 'queue full',
      DfuBootloaderStatusCode.bootMetadataError => 'boot metadata error',
      DfuBootloaderStatusCode.unknown =>
        'unknown 0x${status.rawCode.toRadixString(16).padLeft(2, '0').toUpperCase()}',
    };
    return '$codeLabel  •  session ${status.sessionId}  •  offset 0x${status.expectedOffset.toRadixString(16).padLeft(8, '0').toUpperCase()}';
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colorScheme = theme.colorScheme;
    final isFailed = progress.state == DfuUpdateState.failed;

    return PopScope(
      canPop: false,
      child: Scaffold(
        backgroundColor: colorScheme.surface,
        body: SafeArea(
          child: Column(
            children: [
              if (_isRunning)
                Container(
                  width: double.infinity,
                  padding:
                      const EdgeInsets.symmetric(horizontal: 20, vertical: 12),
                  color: colorScheme.errorContainer,
                  child: Row(
                    children: [
                      Icon(Icons.warning_amber_rounded,
                          color: colorScheme.onErrorContainer, size: 20),
                      const SizedBox(width: 10),
                      Expanded(
                        child: Text(
                          'Do not close the app, lock the phone, or move away from the button.',
                          style: theme.textTheme.bodySmall?.copyWith(
                            color: colorScheme.onErrorContainer,
                            fontWeight: FontWeight.w600,
                          ),
                        ),
                      ),
                    ],
                  ),
                ),
              Expanded(
                child: SingleChildScrollView(
                  padding: const EdgeInsets.fromLTRB(24, 32, 24, 24),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: [
                      Icon(
                        _isTerminal
                            ? (isFailed
                                ? Icons.error_outline_rounded
                                : Icons.check_circle_outline_rounded)
                            : Icons.system_update_alt_rounded,
                        size: 56,
                        color: _isTerminal
                            ? (isFailed
                                ? colorScheme.error
                                : colorScheme.primary)
                            : colorScheme.primary,
                      ),
                      const SizedBox(height: 16),
                      Text(
                        _isTerminal
                            ? (isFailed ? 'Update failed' : 'Update completed')
                            : 'Updating firmware',
                        style: theme.textTheme.headlineSmall?.copyWith(
                          fontWeight: FontWeight.w700,
                        ),
                      ),
                      const SizedBox(height: 8),
                      Text(
                        phaseText,
                        style: theme.textTheme.bodyLarge?.copyWith(
                          color: colorScheme.onSurface.withValues(alpha: 0.72),
                        ),
                      ),
                      if (selectedFirmware != null) ...[
                        const SizedBox(height: 12),
                        Text(
                          '${selectedFirmware!.fileName}  •  ${_formatBytes(selectedFirmware!.fileBytes.length)}',
                          style: theme.textTheme.bodySmall,
                        ),
                      ],
                      const SizedBox(height: 24),
                      if (_isRunning) ...[
                        LinearProgressIndicator(
                          value: progress.totalBytes > 0
                              ? progress.fractionComplete
                              : null,
                          minHeight: 12,
                          borderRadius: BorderRadius.circular(999),
                        ),
                        const SizedBox(height: 12),
                        Text(
                          '${progress.percentComplete}%  •  $formattedProgressBytes',
                          style: theme.textTheme.bodyMedium?.copyWith(
                            fontWeight: FontWeight.w600,
                          ),
                        ),
                      ],
                      if (progress.state == DfuUpdateState.finishing ||
                          progress.state == DfuUpdateState.rebooting ||
                          progress.state == DfuUpdateState.verifying) ...[
                        const SizedBox(height: 20),
                        Container(
                          width: double.infinity,
                          padding: const EdgeInsets.all(14),
                          decoration: BoxDecoration(
                            color: colorScheme.primaryContainer
                                .withValues(alpha: 0.36),
                            borderRadius: BorderRadius.circular(14),
                          ),
                          child: Row(
                            children: [
                              SizedBox(
                                width: 18,
                                height: 18,
                                child: CircularProgressIndicator(
                                    strokeWidth: 2, color: colorScheme.primary),
                              ),
                              const SizedBox(width: 10),
                              Expanded(
                                child: Text(
                                  'Bootloader is verifying, resetting, and booting the new app. Keep the screen open.',
                                  style: theme.textTheme.bodySmall?.copyWith(
                                    color: colorScheme.primary,
                                    fontWeight: FontWeight.w600,
                                  ),
                                ),
                              ),
                            ],
                          ),
                        ),
                      ],
                      if (_bootloaderStatusText != null) ...[
                        const SizedBox(height: 12),
                        Text(
                          _bootloaderStatusText!,
                          style: theme.textTheme.bodySmall?.copyWith(
                            color:
                                colorScheme.onSurface.withValues(alpha: 0.56),
                          ),
                        ),
                      ],
                      if (statusText != null &&
                          statusText!.trim().isNotEmpty) ...[
                        const SizedBox(height: 20),
                        Container(
                          width: double.infinity,
                          padding: const EdgeInsets.all(14),
                          decoration: BoxDecoration(
                            color: isFailed
                                ? colorScheme.errorContainer
                                : colorScheme.surfaceContainerHighest,
                            borderRadius: BorderRadius.circular(14),
                          ),
                          child: Text(
                            statusText!,
                            style: theme.textTheme.bodyMedium?.copyWith(
                              color: isFailed
                                  ? colorScheme.onErrorContainer
                                  : null,
                            ),
                          ),
                        ),
                      ],
                      if (_isTerminal) ...[
                        const SizedBox(height: 32),
                        SizedBox(
                          width: double.infinity,
                          child: FilledButton.icon(
                            onPressed: onDismiss,
                            icon: Icon(isFailed
                                ? Icons.arrow_back_rounded
                                : Icons.check_rounded),
                            label: Text(isFailed ? failedLabel : doneLabel),
                          ),
                        ),
                      ],
                    ],
                  ),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  String _formatBytes(int bytes) {
    if (bytes < 1024) return '$bytes B';
    if (bytes < 1024 * 1024) return '${(bytes / 1024).toStringAsFixed(1)} KB';
    return '${(bytes / (1024 * 1024)).toStringAsFixed(2)} MB';
  }
}