/// State model for the problems panel.
///
/// Aggregates diagnostic information from pql.doctor and
/// pql.decisions.validate (via pql.decisions.sync which reports
/// broken refs). Refreshes on demand.
library;

import 'dart:async';

import 'package:clide/kernel/kernel.dart';
import 'package:flutter/foundation.dart';

class Problem {
  const Problem({required this.source, required this.message, this.hint});
  final String source;
  final String message;
  final String? hint;

  Map<String, Object?> toJson() => {
        'source': source,
        'message': message,
        if (hint != null) 'hint': hint,
      };
}

class ProblemsController extends ChangeNotifier {
  ProblemsController({required this.ipc});

  final DaemonClient ipc;

  List<Problem> _problems = const [];
  List<Problem> get problems => _problems;

  bool _loading = false;
  bool get loading => _loading;

  String? _error;
  String? get error => _error;

  Future<void> refresh() async {
    _loading = true;
    notifyListeners();

    final found = <Problem>[];

    final doctor = await ipc.request('pql.doctor');
    if (doctor.ok) {
      final db = (doctor.data['db'] as Map?)?.cast<String, Object?>();
      if (db != null && db['exists'] == false) {
        found.add(const Problem(
          source: 'pql',
          message: 'pql index database not found',
          hint: 'Run pql to build the index.',
        ));
      }
      final skill = (doctor.data['skill'] as Map?)?.cast<String, Object?>();
      if (skill != null) {
        final project = (skill['project'] as Map?)?.cast<String, Object?>();
        if (project != null) {
          final state = project['state'] as String?;
          if (state == 'stale') {
            found.add(const Problem(
              source: 'pql',
              message: 'pql skill is stale — newer version available',
              hint: 'Run: pql skill install',
            ));
          } else if (state == 'missing') {
            found.add(const Problem(
              source: 'pql',
              message: 'pql skill not installed',
              hint: 'Run: pql init --with-skill=yes',
            ));
          }
        }
      }
    } else {
      found.add(Problem(
        source: 'pql',
        message: 'pql doctor failed',
        hint: doctor.error?.message,
      ));
    }

    final sync = await ipc.request('pql.decisions.sync');
    if (sync.ok) {
      final broken = (sync.data['broken'] as num?)?.toInt() ?? 0;
      if (broken > 0) {
        found.add(Problem(
          source: 'decisions',
          message: '$broken broken cross-reference(s) in decisions/',
          hint: 'Run: pql decisions validate',
        ));
      }
    }

    _loading = false;
    _error = null;
    _problems = found;
    notifyListeners();
  }
}