import 'package:aioa_mobile/features/form/application/leave_attachment_controller.dart';
import 'package:file_picker/file_picker.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

class LeaveAttachmentSheet extends ConsumerStatefulWidget {
  const LeaveAttachmentSheet({required this.leaveRequestId, super.key});

  final String leaveRequestId;

  @override
  ConsumerState<LeaveAttachmentSheet> createState() =>
      _LeaveAttachmentSheetState();
}

class _LeaveAttachmentSheetState extends ConsumerState<LeaveAttachmentSheet> {
  @override
  void initState() {
    super.initState();
    Future.microtask(
      () => ref
          .read(leaveAttachmentProvider(widget.leaveRequestId).notifier)
          .load(),
    );
  }

  @override
  Widget build(BuildContext context) {
    final state = ref.watch(leaveAttachmentProvider(widget.leaveRequestId));
    return SafeArea(
      child: Padding(
        padding: EdgeInsets.fromLTRB(
          20,
          0,
          20,
          20 + MediaQuery.viewInsetsOf(context).bottom,
        ),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Text(
              '添加附件',
              style: Theme.of(
                context,
              ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.w700),
            ),
            const SizedBox(height: 6),
            const Text('支持 JPEG、PNG、PDF，单个文件不超过 10 MB。文件将直接上传至对象存储。'),
            if (state.error != null) ...[
              const SizedBox(height: 10),
              Text(
                state.error!,
                style: TextStyle(color: Theme.of(context).colorScheme.error),
              ),
            ],
            if (state.uploading) ...[
              const SizedBox(height: 14),
              LinearProgressIndicator(value: state.progress),
              const SizedBox(height: 6),
              Text('正在上传 ${(state.progress * 100).round()}%'),
            ],
            if (state.items.isNotEmpty) ...[
              const SizedBox(height: 14),
              for (final item in state.items)
                ListTile(
                  contentPadding: EdgeInsets.zero,
                  leading: Icon(
                    item.contentType == 'application/pdf'
                        ? Icons.picture_as_pdf_outlined
                        : Icons.image_outlined,
                  ),
                  title: Text(
                    item.fileName,
                    maxLines: 1,
                    overflow: TextOverflow.ellipsis,
                  ),
                  subtitle: Text(
                    '${_formatBytes(item.sizeBytes)} · ${item.status == 'READY' ? '已上传' : '处理中'}',
                  ),
                  trailing: item.status == 'READY'
                      ? const Icon(Icons.check_circle, color: Colors.green)
                      : null,
                ),
            ],
            const SizedBox(height: 14),
            OutlinedButton.icon(
              onPressed: state.uploading ? null : _pickAndUpload,
              icon: const Icon(Icons.attach_file),
              label: const Padding(
                padding: EdgeInsets.symmetric(vertical: 12),
                child: Text('选择附件'),
              ),
            ),
            const SizedBox(height: 8),
            FilledButton(
              onPressed: state.uploading ? null : () => Navigator.pop(context),
              child: const Text('完成'),
            ),
          ],
        ),
      ),
    );
  }

  Future<void> _pickAndUpload() async {
    final result = await FilePicker.platform.pickFiles(
      type: FileType.custom,
      allowedExtensions: const ['jpg', 'jpeg', 'png', 'pdf'],
      withData: true,
    );
    if (result == null || !mounted) return;
    final file = result.files.single;
    final bytes = file.bytes;
    if (bytes == null) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(const SnackBar(content: Text('无法读取所选文件')));
      return;
    }
    final contentType = switch (file.extension?.toLowerCase()) {
      'jpg' || 'jpeg' => 'image/jpeg',
      'png' => 'image/png',
      'pdf' => 'application/pdf',
      _ => null,
    };
    if (contentType == null) return;
    await ref
        .read(leaveAttachmentProvider(widget.leaveRequestId).notifier)
        .upload(fileName: file.name, contentType: contentType, bytes: bytes);
  }

  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(1)} MB';
  }
}