import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';

import '../api.dart';
import '../pickers.dart';
import '../theme.dart';
import '../widgets.dart';

const _tabs = {
  'pending': 'Waiting',
  'needs_info': 'Asked for more',
  'approved': 'Approved',
  'rejected': 'Rejected',
};

/// Singers and creators asking to be verified (the "I'm a singer" form in the app).
class ApplicationsScreen extends StatefulWidget {
  const ApplicationsScreen({super.key});

  @override
  State<ApplicationsScreen> createState() => _ApplicationsScreenState();
}

class _ApplicationsScreenState extends State<ApplicationsScreen> {
  String _status = 'pending';
  late Future<List<CreatorApplication>> _data = AdminApi.applications(_status);

  void _reload() => setState(() => _data = AdminApi.applications(_status));

  Future<void> _approve(CreatorApplication app) async {
    final artists = await AdminApi.artists();
    if (!mounted) return;
    var link = <String>[if (app.artistId != null) app.artistId!];
    final note = TextEditingController();
    final ok = await showDialog<bool>(
      context: context,
      builder: (context) => StatefulBuilder(
        builder: (context, setLocal) => AlertDialog(
          title: Text('Approve ${app.stageName}'),
          content: DialogBody(children: [
            const Text('If this singer is already in the catalog, choose them so their songs are linked to this '
                'account. Otherwise a new verified singer is created.'),
            SingerPicker(
              artists: artists,
              selected: link,
              onChanged: (v) => setLocal(() => link = v.isEmpty ? v : [v.last]),
            ),
            TextField(controller: note, decoration: const InputDecoration(labelText: 'Note (optional)')),
          ]),
          actions: [
            TextButton(onPressed: () => Navigator.pop(context, false), child: const Text('Cancel')),
            FilledButton(onPressed: () => Navigator.pop(context, true), child: const Text('Approve')),
          ],
        ),
      ),
    );
    if (ok == true) {
      await _review(app, 'approved', trimmedOrNull(note.text), link.isEmpty ? null : link.single);
    }
  }

  Future<void> _decline(CreatorApplication app, String decision) async {
    final note = TextEditingController();
    final ask = decision == 'needs_info';
    final ok = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(ask ? 'Ask ${app.stageName} for more' : 'Reject ${app.stageName}'),
        content: DialogBody(children: [
          TextField(
            controller: note,
            autofocus: true,
            maxLines: 3,
            decoration: InputDecoration(labelText: ask ? 'What do you need from them?' : 'Reason'),
          ),
        ]),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context, false), child: const Text('Cancel')),
          FilledButton(
            style: ask ? null : FilledButton.styleFrom(backgroundColor: NkColors.roofRed, foregroundColor: NkColors.cream),
            onPressed: () => Navigator.pop(context, true),
            child: Text(ask ? 'Send back' : 'Reject'),
          ),
        ],
      ),
    );
    if (ok == true) await _review(app, decision, trimmedOrNull(note.text), null);
  }

  Future<void> _review(CreatorApplication app, String decision, String? note, String? artistId) async {
    try {
      await AdminApi.reviewApplication(app.id, decision, note: note, artistId: artistId);
      if (mounted) showMessage(context, '${app.stageName}: ${_tabs[decision]!.toLowerCase()}');
      _reload();
    } catch (e) {
      if (mounted) showError(context, e);
    }
  }

  Future<void> _openDocument(String path) async {
    try {
      await launchUrl(Uri.parse(await AdminApi.idDocumentUrl(path)));
    } catch (e) {
      if (mounted) showError(context, e);
    }
  }

  @override
  Widget build(BuildContext context) => Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          PageHeader('Creator applications', subtitle: 'Verify singers and creators before they can upload', actions: [
            SegmentedButton<String>(
              segments: [for (final e in _tabs.entries) ButtonSegment(value: e.key, label: Text(e.value))],
              selected: {_status},
              onSelectionChanged: (s) {
                _status = s.first;
                _reload();
              },
            ),
          ]),
          Expanded(
            child: Loader(
              future: _data,
              onRetry: _reload,
              builder: (context, apps) => apps.isEmpty
                  ? const EmptyState('No applications here.', icon: Icons.how_to_reg_outlined)
                  : ListView.separated(
                      padding: const EdgeInsets.fromLTRB(24, 0, 24, 24),
                      itemCount: apps.length,
                      separatorBuilder: (_, _) => const SizedBox(height: 12),
                      itemBuilder: (context, i) => _card(apps[i]),
                    ),
            ),
          ),
        ],
      );

  Widget _card(CreatorApplication a) {
    final small = Theme.of(context).textTheme.bodySmall;
    final open = a.status == 'pending' || a.status == 'needs_info';
    Widget fact(String label, String? value, {String? link}) => value == null || value.isEmpty
        ? const SizedBox.shrink()
        : Padding(
            padding: const EdgeInsets.only(bottom: 4),
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                SizedBox(width: 120, child: Text(label, style: small)),
                Expanded(
                  child: link == null
                      ? SelectableText(value)
                      : InkWell(
                          onTap: () => launchUrl(Uri.parse(link)),
                          child: Text(value, style: const TextStyle(color: NkColors.sun, decoration: TextDecoration.underline)),
                        ),
                ),
              ],
            ),
          );
    String? web(String? s) => s == null || s.isEmpty ? null : (s.startsWith('http') ? s : 'https://$s');
    String? instagram(String? s) =>
        s == null || s.isEmpty ? null : (s.startsWith('http') ? s : 'https://instagram.com/${s.replaceAll('@', '')}');
    String? whatsapp(String? s) =>
        s == null || s.isEmpty ? null : 'https://wa.me/${s.replaceAll(RegExp(r'[^0-9]'), '')}';

    return Card(
      child: Padding(
        padding: const EdgeInsets.all(20),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Expanded(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(a.stageName, style: Theme.of(context).textTheme.titleLarge),
                      Text('Applied ${formatDate(a.createdAt)}', style: small),
                    ],
                  ),
                ),
                if (a.idDocumentPath != null)
                  OutlinedButton.icon(
                    onPressed: () => _openDocument(a.idDocumentPath!),
                    icon: const Icon(Icons.badge_outlined, size: 18),
                    label: const Text('View ID'),
                  )
                else
                  const Tag('No ID uploaded', color: NkColors.roofRed),
              ],
            ),
            const SizedBox(height: 14),
            fact('Real name', a.realName),
            fact('Account', [?a.displayName, ?a.email].join(' · ')),
            fact('Phone', a.phone),
            fact('Village / hatti', a.hattiName),
            fact('Instagram', a.instagram, link: instagram(a.instagram)),
            fact('WhatsApp', a.whatsapp, link: whatsapp(a.whatsapp)),
            for (final l in a.workLinks) fact('Work', l, link: web(l)),
            fact('Their songs', a.claimedSongs),
            fact('Message', a.message),
            fact('Review note', a.reviewNote),
            if (open) ...[
              const SizedBox(height: 12),
              Wrap(
                spacing: 8,
                runSpacing: 8,
                children: [
                  FilledButton.icon(
                    onPressed: () => _approve(a),
                    icon: const Icon(Icons.verified_outlined, size: 18),
                    label: const Text('Approve'),
                  ),
                  if (a.status == 'pending')
                    OutlinedButton(onPressed: () => _decline(a, 'needs_info'), child: const Text('Ask for more')),
                  OutlinedButton(onPressed: () => _decline(a, 'rejected'), child: const Text('Reject')),
                ],
              ),
            ],
          ],
        ),
      ),
    );
  }
}