// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef __CREDENTIALS_HPP__
#define __CREDENTIALS_HPP__

#include <string>
#include <vector>

#include <stout/option.hpp>
#include <stout/path.hpp>
#include <stout/protobuf.hpp>
#include <stout/try.hpp>

#include <stout/os/permissions.hpp>
#include <stout/os/read.hpp>

namespace mesos {
namespace internal {
namespace credentials {

inline Result<Credentials> read(const Path& path)
{
  LOG(INFO) << "Loading credentials for authentication from '" << path << "'";

  Try<std::string> read = os::read(path.string());
  if (read.isError()) {
    return Error("Failed to read credentials file '" + path.string() +
                 "': " + read.error());
  } else if (read->empty()) {
    return None();
  }

  Try<os::Permissions> permissions = os::permissions(path.string());
  if (permissions.isError()) {
    LOG(WARNING) << "Failed to stat credentials file '" << path
                 << "': " << permissions.error();
  } else if (permissions->others.rwx) {
    LOG(WARNING) << "Permissions on credentials file '" << path
                 << "' are too open; it is recommended that your"
                 << " credentials file is NOT accessible by others";
  }

  Try<JSON::Object> json = JSON::parse<JSON::Object>(read.get());
  if (json.isError()) {
    return Error("Invalid json format: " + json.error());
  }

  Try<Credentials> credentials = ::protobuf::parse<Credentials>(json.get());
  if (credentials.isError()) {
    return Error("Failed to parse credentials: "
                 + credentials.error());
  }
  return credentials.get();
}


inline Result<Credential> readCredential(const Path& path)
{
  LOG(INFO) << "Loading credential for authentication from '" << path << "'";

  Try<std::string> read = os::read(path.string());
  if (read.isError()) {
    return Error("Failed to read credential file '" + path.string() +
                 "': " + read.error());
  } else if (read->empty()) {
    return None();
  }

  Try<os::Permissions> permissions = os::permissions(path.string());
  if (permissions.isError()) {
    LOG(WARNING) << "Failed to stat credential file '" << path
                 << "': " << permissions.error();
  } else if (permissions->others.rwx) {
    LOG(WARNING) << "Permissions on credential file '" << path
                 << "' are too open; it is recommended that your"
                 << " credential file is NOT accessible by others";
  }

  Try<JSON::Object> json = JSON::parse<JSON::Object>(read.get());
  if (json.isError()) {
    return Error("Invalid json format: " + json.error());
  }

  Try<Credential> credential = ::protobuf::parse<Credential>(json.get());
  if (credential.isError()) {
    return Error("Failed to parse credential: "
                 + credential.error());
  }
  return credential.get();
}

} // namespace credentials {
} // namespace internal {
} // namespace mesos {

#endif // __CREDENTIALS_HPP__