/*
 * 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.
 */
#pragma once

#include <chrono>
#include <memory>
#include <mutex>
#include <utility>

#include "Credentials.h"

ROCKETMQ_NAMESPACE_BEGIN

class CredentialsProvider {
public:
  virtual ~CredentialsProvider() = default;

  virtual Credentials getCredentials() = 0;
};

using CredentialsProviderPtr = std::shared_ptr<CredentialsProvider>;

class StaticCredentialsProvider : public CredentialsProvider {
public:
  StaticCredentialsProvider(std::string access_key, std::string access_secret);

  ~StaticCredentialsProvider() override = default;

  Credentials getCredentials() override;

private:
  std::string access_key_;
  std::string access_secret_;
};

/**
 * Read credentials from environment variables ROCKETMQ_ACCESS_KEY, ROCKETMQ_ACCESS_SECRET
 */
class EnvironmentVariablesCredentialsProvider : public CredentialsProvider {
public:
  EnvironmentVariablesCredentialsProvider();

  ~EnvironmentVariablesCredentialsProvider() override = default;

  Credentials getCredentials() override;

  static const char* ENVIRONMENT_ACCESS_KEY;
  static const char* ENVIRONMENT_ACCESS_SECRET;

private:
  std::string access_key_;
  std::string access_secret_;
};

/**
 * Read credentials from configuration file: ~/rocketmq/credentials. By default, the client library would refresh every
 * 10 seconds.
 */
class ConfigFileCredentialsProvider : public CredentialsProvider {
public:
  ConfigFileCredentialsProvider();

  ConfigFileCredentialsProvider(std::string config_file, std::chrono::milliseconds refresh_interval);

  Credentials getCredentials() override;

  /**
   * For test purpose only.
   * @return
   */
  static const char* credentialFile() {
    return CREDENTIAL_FILE_;
  }

private:
  std::chrono::system_clock::duration refresh_interval_{std::chrono::seconds(10)};
  std::string access_key_;
  std::string access_secret_;
  static const char* CREDENTIAL_FILE_;
  static const char* ACCESS_KEY_FIELD_NAME;
  static const char* ACCESS_SECRET_FIELD_NAME;
};

class StsCredentialsProviderImpl;

class StsCredentialsProvider : public CredentialsProvider {
public:
  explicit StsCredentialsProvider(std::string ram_role_name);

  Credentials getCredentials() override;

private:
  std::unique_ptr<StsCredentialsProviderImpl> impl_;
};

ROCKETMQ_NAMESPACE_END