// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'base_client.dart';
import 'base_request.dart';

/// The base class for HTTP responses.
///
/// Subclasses of [BaseResponse] are usually not constructed manually; instead,
/// they're returned by [BaseClient.send] or other HTTP client methods.
abstract class BaseResponse {
  /// The (frozen) request that triggered this response.
  final BaseRequest? request;

  /// The HTTP status code for this response.
  final int statusCode;

  /// The reason phrase associated with the status code.
  final String? reasonPhrase;

  /// The size of the response body, in bytes.
  ///
  /// If the size of the request is not known in advance, this is `null`.
  final int? contentLength;

  // TODO(nweiz): automatically parse cookies from headers

  /// The HTTP headers returned by the server.
  ///
  /// The header names are converted to lowercase and stored with their
  /// associated header values.
  ///
  /// If the server returns multiple headers with the same name then the header
  /// values will be associated with a single key and seperated by commas and
  /// possibly whitespace. For example:
  /// ```dart
  /// // HTTP/1.1 200 OK
  /// // Fruit: Apple
  /// // Fruit: Banana
  /// // Fruit: Grape
  /// final values = response.headers['fruit']!.split(RegExp(r'\s*,\s*'));
  /// // values = ['Apple', 'Banana', 'Grape']
  /// ```
  ///
  /// If a header value contains whitespace then that whitespace may be replaced
  /// by a single space. Leading and trailing whitespace in header values are
  /// always removed.
  // TODO(nweiz): make this a HttpHeaders object.
  final Map<String, String> headers;

  final bool isRedirect;

  /// Whether the server requested that a persistent connection be maintained.
  final bool persistentConnection;

  BaseResponse(this.statusCode,
      {this.contentLength,
      this.request,
      this.headers = const {},
      this.isRedirect = false,
      this.persistentConnection = true,
      this.reasonPhrase}) {
    if (statusCode < 100) {
      throw ArgumentError('Invalid status code $statusCode.');
    } else if (contentLength != null && contentLength! < 0) {
      throw ArgumentError('Invalid content length $contentLength.');
    }
  }
}