import 'dart:convert';
import 'dart:typed_data';

import 'package:dio/dio.dart';

/// Sequential fake adapter for deterministic Dio unit tests.
typedef AdapterHandler =
    Future<ResponseBody> Function(
      RequestOptions options,
      Stream<Uint8List>? requestStream,
      Future<void>? cancelFuture,
    );

class QueueHttpClientAdapter implements HttpClientAdapter {
  QueueHttpClientAdapter(List<AdapterHandler> handlers)
    : _handlers = List<AdapterHandler>.from(handlers);

  final List<AdapterHandler> _handlers;
  int fetchCount = 0;

  @override
  void close({bool force = false}) {}

  @override
  Future<ResponseBody> fetch(
    RequestOptions options,
    Stream<Uint8List>? requestStream,
    Future<void>? cancelFuture,
  ) async {
    if (fetchCount >= _handlers.length) {
      throw StateError(
        'No queued response for ${options.method} ${options.path} at call $fetchCount',
      );
    }

    final AdapterHandler handler = _handlers[fetchCount];
    fetchCount += 1;
    return handler(options, requestStream, cancelFuture);
  }
}

ResponseBody jsonResponse(
  int statusCode,
  Map<String, dynamic> body, {
  Map<String, List<String>> headers = const <String, List<String>>{},
}) {
  return ResponseBody.fromString(
    jsonEncode(body),
    statusCode,
    headers: <String, List<String>>{
      Headers.contentTypeHeader: <String>[Headers.jsonContentType],
      ...headers,
    },
  );
}