import 'dart:convert';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:accessible_terminal/models/saved_connection.dart';

// Key for SharedPreferences
const String _kSavedConnectionsKey = 'saved_connections';

class SavedConnectionsNotifier extends StateNotifier<List<SavedConnection>> {
  SavedConnectionsNotifier() : super([]) {
    _loadConnections();
  }

  Future<void> _loadConnections() async {
    final prefs = await SharedPreferences.getInstance();
    final String? jsonString = prefs.getString(_kSavedConnectionsKey);
    if (jsonString != null) {
      try {
        final List<dynamic> jsonList = jsonDecode(jsonString);
        state = jsonList.map((e) => SavedConnection.fromJson(e)).toList();
      } catch (e) {
        // Handle corruption or format change gracefully
        state = [];
      }
    }
  }

  Future<void> addConnection({
    required String host,
    required int port,
    required String username,
    String? privateKey,
  }) async {
    // Check for duplicates (simple check based on host/user/port)
    final exists = state.any((c) => 
      c.host == host && c.port == port && c.username == username
    );
    
    if (exists) return; // Don't save if already exists
    
    // Use timestamp for simple ID generation
    final simpleId = DateTime.now().millisecondsSinceEpoch.toString();
     final connection = SavedConnection(
      id: simpleId,
      host: host,
      port: port,
      username: username,
      privateKey: privateKey,
    );

    state = [...state, connection];
    await _saveToDisk();
  }

  Future<void> removeConnection(String id) async {
    state = state.where((c) => c.id != id).toList();
    await _saveToDisk();
  }

  Future<void> _saveToDisk() async {
    final prefs = await SharedPreferences.getInstance();
    final jsonList = state.map((c) => c.toJson()).toList();
    await prefs.setString(_kSavedConnectionsKey, jsonEncode(jsonList));
  }
}

final savedConnectionsProvider = StateNotifierProvider<SavedConnectionsNotifier, List<SavedConnection>>((ref) {
  return SavedConnectionsNotifier();
});