/// Smart Event Network — Flutter / Dart SDK (v1)
///
/// Add to pubspec.yaml: `http: ^1.2.0`
///
/// ```dart
/// final sen = SmartEventClient(apiKey: 'sen_live_...');
/// final events = await sen.listEvents();
/// final result = await sen.scan(eventId: '...', token: 'SEN1....');
/// ```
library smart_event_card;

import 'dart:convert';
import 'package:http/http.dart' as http;

class SmartEventApiException implements Exception {
  final String message;
  final int status;
  final dynamic body;
  SmartEventApiException(this.message, this.status, this.body);
  @override
  String toString() => 'SmartEventApiException($status): $message';
}

class SmartEventClient {
  final String apiKey;
  final String baseUrl;
  final http.Client _client;

  SmartEventClient({
    required this.apiKey,
    this.baseUrl = 'https://smarteventnetwork.com/api/public/v1',
    http.Client? client,
  }) : _client = client ?? http.Client() {
    if (!apiKey.startsWith('sen_live_')) {
      throw ArgumentError('apiKey must start with sen_live_');
    }
  }

  Map<String, String> get _headers => {
        'authorization': 'Bearer $apiKey',
        'content-type': 'application/json',
        'accept': 'application/json',
      };

  Future<dynamic> _request(String method, String path, [Map<String, dynamic>? body]) async {
    final uri = Uri.parse('$baseUrl$path');
    final res = await (method == 'GET'
        ? _client.get(uri, headers: _headers)
        : _client.post(uri, headers: _headers, body: body != null ? jsonEncode(body) : null));
    Map<String, dynamic> json;
    try {
      json = res.body.isEmpty ? {} : jsonDecode(res.body) as Map<String, dynamic>;
    } catch (_) {
      throw SmartEventApiException('Invalid JSON', res.statusCode, res.body);
    }
    if (res.statusCode >= 400) {
      throw SmartEventApiException(
          json['error']?.toString() ?? 'HTTP ${res.statusCode}', res.statusCode, json);
    }
    return json['data'] ?? json;
  }

  Future<List<dynamic>> listEvents() async => (await _request('GET', '/events')) as List;
  Future<Map<String, dynamic>> getEvent(String id) async =>
      (await _request('GET', '/events/$id')) as Map<String, dynamic>;

  Future<Map<String, dynamic>> verifyCard(String token) async =>
      (await _request('GET', '/card/verify?token=${Uri.encodeComponent(token)}'))
          as Map<String, dynamic>;

  Future<Map<String, dynamic>> scan({
    required String eventId,
    String? cardNumber,
    String? token,
  }) async {
    final body = <String, dynamic>{'event_id': eventId};
    if (cardNumber != null) body['card_number'] = cardNumber;
    if (token != null) body['token'] = token;
    return (await _request('POST', '/scan', body)) as Map<String, dynamic>;
  }

  void close() => _client.close();
}