// Copyright 2015 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "buffet/http_transport_client.h"

#include <base/bind.h>
#include <chromeos/errors/error.h>
#include <chromeos/http/http_request.h>
#include <chromeos/http/http_utils.h>
#include <chromeos/streams/memory_stream.h>

#include "buffet/weave_error_conversion.h"

namespace buffet {

namespace {

using weave::provider::HttpClient;

// The number of seconds each HTTP request will be allowed before timing out.
const int kRequestTimeoutSeconds = 30;

class ResponseImpl : public HttpClient::Response {
 public:
  ~ResponseImpl() override = default;
  explicit ResponseImpl(std::unique_ptr<chromeos::http::Response> response)
      : response_{std::move(response)},
        data_{response_->ExtractDataAsString()} {}

  // HttpClient::Response implementation
  int GetStatusCode() const override { return response_->GetStatusCode(); }

  std::string GetContentType() const override {
    return response_->GetContentType();
  }

  const std::string& GetData() const override { return data_; }

 private:
  std::unique_ptr<chromeos::http::Response> response_;
  std::string data_;
  DISALLOW_COPY_AND_ASSIGN(ResponseImpl);
};

void OnSuccessCallback(const HttpClient::SuccessCallback& success_callback,
                       int id,
                       std::unique_ptr<chromeos::http::Response> response) {
  success_callback.Run(id, ResponseImpl{std::move(response)});
}

void OnErrorCallback(const HttpClient::ErrorCallback& error_callback,
                     int id,
                     const chromeos::Error* chromeos_error) {
  weave::ErrorPtr error;
  ConvertError(*chromeos_error, &error);
  error_callback.Run(id, error.get());
}

}  // anonymous namespace

HttpTransportClient::HttpTransportClient()
    : transport_{chromeos::http::Transport::CreateDefault()} {
  transport_->SetDefaultTimeout(
      base::TimeDelta::FromSeconds(kRequestTimeoutSeconds));
}

HttpTransportClient::~HttpTransportClient() {}

std::unique_ptr<HttpClient::Response> HttpTransportClient::SendRequestAndBlock(
    const std::string& method,
    const std::string& url,
    const Headers& headers,
    const std::string& data,
    weave::ErrorPtr* error) {
  chromeos::http::Request request(url, method, transport_);
  request.AddHeaders(headers);
  if (!data.empty()) {
    chromeos::ErrorPtr cromeos_error;
    if (!request.AddRequestBody(data.data(), data.size(), &cromeos_error)) {
      ConvertError(*cromeos_error, error);
      return nullptr;
    }
  }

  chromeos::ErrorPtr cromeos_error;
  auto response = request.GetResponseAndBlock(&cromeos_error);
  if (!response) {
    ConvertError(*cromeos_error, error);
    return nullptr;
  }

  return std::unique_ptr<HttpClient::Response>{
      new ResponseImpl{std::move(response)}};
}

int HttpTransportClient::SendRequest(const std::string& method,
                                     const std::string& url,
                                     const Headers& headers,
                                     const std::string& data,
                                     const SuccessCallback& success_callback,
                                     const ErrorCallback& error_callback) {
  chromeos::http::Request request(url, method, transport_);
  request.AddHeaders(headers);
  if (!data.empty()) {
    auto stream = chromeos::MemoryStream::OpenCopyOf(data, nullptr);
    CHECK(stream->GetRemainingSize());
    chromeos::ErrorPtr cromeos_error;
    if (!request.AddRequestBody(std::move(stream), &cromeos_error)) {
      weave::ErrorPtr error;
      ConvertError(*cromeos_error, &error);
      transport_->RunCallbackAsync(
          FROM_HERE,
          base::Bind(error_callback, 0, base::Owned(error.release())));
      return 0;
    }
  }
  return request.GetResponse(base::Bind(&OnSuccessCallback, success_callback),
                             base::Bind(&OnErrorCallback, error_callback));
}

}  // namespace buffet