// 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.

library io_client;

import 'dart:async';

import 'package:stack_trace/stack_trace.dart';

import 'base_client.dart';
import 'base_request.dart';
import 'exception.dart';
import 'io.dart' as io;
import 'streamed_response.dart';

/// A `dart:io`-based HTTP client.
///
/// This is the default client when running on the command line.
class IOClient extends BaseClient {
  /// The underlying `dart:io` HTTP client.
  var _inner;

  /// Creates a new HTTP client.
  ///
  /// [innerClient] must be a `dart:io` HTTP client. If it's not passed, a
  /// default one will be instantiated.
  IOClient([innerClient]) {
    io.assertSupported("IOClient");
    if (innerClient != null) {
      // TODO(nweiz): remove this assert when we can type [innerClient]
      // properly.
      assert(io.isHttpClient(innerClient));
      _inner = innerClient;
    } else {
      _inner = io.newHttpClient();
    }
  }

  /// Sends an HTTP request and asynchronously returns the response.
  Future<StreamedResponse> send(BaseRequest request) {
    var stream = request.finalize();

    return Chain.track(_inner.openUrl(request.method, request.url))
        .then((ioRequest) {
      var contentLength = request.contentLength == null ?
          -1 : request.contentLength;
      ioRequest
          ..followRedirects = request.followRedirects
          ..maxRedirects = request.maxRedirects
          ..contentLength = contentLength
          ..persistentConnection = request.persistentConnection;
      request.headers.forEach((name, value) {
        ioRequest.headers.set(name, value);
      });
      return Chain.track(stream.pipe(ioRequest));
    }).then((response) {
      var headers = {};
      response.headers.forEach((key, values) {
        headers[key] = values.join(',');
      });

      var contentLength = response.contentLength == -1 ?
          null : response.contentLength;
      return new StreamedResponse(
          response.handleError((error) =>
              throw new ClientException(error.message, error.uri),
              test: (error) => io.isHttpException(error)),
          response.statusCode,
          contentLength: contentLength,
          request: request,
          headers: headers,
          isRedirect: response.isRedirect,
          persistentConnection: response.persistentConnection,
          reasonPhrase: response.reasonPhrase);
    }).catchError((error) {
      if (!io.isHttpException(error)) throw error;
      throw new ClientException(error.message, error.uri);
    });
  }

  /// Closes the client. This terminates all active connections. If a client
  /// remains unclosed, the Dart process may not terminate.
  void close() {
    if (_inner != null) _inner.close(force: true);
    _inner = null;
  }
}