import 'dart:convert';
import 'dart:io';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:path_provider/path_provider.dart';
import 'package:share_plus/share_plus.dart';
import '../core/app_controller.dart';
import '../l10n/strings.dart';
import '../models/server_profile.dart';
import '../services/net/measure.dart';
import 'common.dart';

const _mime = {
  ReportFormat.txt: 'text/plain',
  ReportFormat.csv: 'text/csv',
  ReportFormat.json: 'application/json',
};

/// Offers a report as text on the clipboard, through the share sheet, or
/// saved to a place the user picks on the device. Nothing is sent anywhere
/// without that explicit choice.
Future<void> showExportSheet(
  BuildContext context,
  AppController c, {
  required String baseName,
  required String Function(ReportFormat) build,
}) async {
  final origin = _origin(context);
  final choice = await showModalBottomSheet<(String, ReportFormat)>(
    context: context,
    isScrollControlled: true,
    builder: (ctx) => SafeArea(
      child: SingleChildScrollView(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            ListTile(
              title: Text(
                ctx.tr('exportResults'),
                style: Theme.of(ctx).textTheme.titleMedium,
              ),
            ),
            for (final f in ReportFormat.values) ...[
              ListTile(
                leading: const Icon(Icons.save_alt),
                title: Text(
                  '${ctx.tr('saveToDevice')} · ${f.name.toUpperCase()}',
                ),
                onTap: () => Navigator.pop(ctx, ('save', f)),
              ),
              ListTile(
                leading: const Icon(Icons.ios_share),
                title: Text('${ctx.tr('shareFile')} · ${f.name.toUpperCase()}'),
                onTap: () => Navigator.pop(ctx, ('share', f)),
              ),
            ],
            ListTile(
              leading: const Icon(Icons.copy),
              title: Text('${ctx.tr('copyResults')} · TXT'),
              onTap: () => Navigator.pop(ctx, ('copy', ReportFormat.txt)),
            ),
          ],
        ),
      ),
    ),
  );
  if (choice == null || !context.mounted) return;
  final (action, format) = choice;
  final text = build(format);
  final name = '$baseName.${format.name}';
  try {
    switch (action) {
      case 'copy':
        await Clipboard.setData(ClipboardData(text: text));
        if (context.mounted) _done(context, 'copied');
      case 'save':
        final saved = await c.withSystemDialog(
          () =>
              c.documents.saveAs(name, utf8.encode(text), mime: _mime[format]),
        );
        if (saved != null && context.mounted) _done(context, 'savedToDevice');
      case 'share':
        await shareText(c, name, text, origin);
    }
  } catch (e) {
    if (context.mounted) showFailure(context, e);
  }
}

Rect _origin(BuildContext context) {
  final box = context.findRenderObject() as RenderBox?;
  final o = box?.localToGlobal(Offset.zero) ?? Offset.zero;
  return Rect.fromLTWH(o.dx, o.dy, 1, 1);
}

void _done(BuildContext context, String key) => ScaffoldMessenger.of(
  context,
).showSnackBar(SnackBar(content: Text(context.tr(key))));

/// Shares [text] as a file named [name] through the system share sheet. The
/// temporary copy is deleted afterwards.
Future<void> shareText(
  AppController c,
  String name,
  String text,
  Rect origin,
) => shareBytes(c, name, utf8.encode(text), origin);

Future<void> shareBytes(
  AppController c,
  String name,
  List<int> bytes,
  Rect origin,
) async {
  final temp = await getTemporaryDirectory();
  final dir = await Directory('${temp.path}/sm-transfer-${newId()}').create();
  try {
    final file = File('${dir.path}/$name');
    await file.writeAsBytes(bytes, flush: true);
    await c.withSystemDialog(
      () => SharePlus.instance.share(
        ShareParams(files: [XFile(file.path)], sharePositionOrigin: origin),
      ),
    );
  } finally {
    if (await dir.exists()) await dir.delete(recursive: true);
  }
}