/*
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#ifndef CLASS_LOADER__MULTI_LIBRARY_CLASS_LOADER_HPP_
#define CLASS_LOADER__MULTI_LIBRARY_CLASS_LOADER_HPP_

#include <cstddef>
#include <map>
#include <memory>
#include <string>
#include <vector>

// TODO(mikaelarguedas) remove this once console_bridge complies with this
// see https://github.com/ros/console_bridge/issues/55
#ifdef __clang__
# pragma clang diagnostic push
# pragma clang diagnostic ignored "-Wgnu-zero-variadic-macro-arguments"
#endif
#include "console_bridge/console.h"
#ifdef __clang__
# pragma clang diagnostic pop
#endif

#include "class_loader/class_loader.hpp"
#include "class_loader/visibility_control.hpp"

namespace class_loader
{

typedef std::string LibraryPath;
typedef std::map<LibraryPath, class_loader::ClassLoader *> LibraryToClassLoaderMap;
typedef std::vector<ClassLoader *> ClassLoaderVector;

class MultiLibraryClassLoaderImpl;

/**
* @class MultiLibraryClassLoader
* @brief A ClassLoader that can bind more than one runtime library
*/
class CLASS_LOADER_PUBLIC MultiLibraryClassLoader
{
public:
  /**
   * @brief Constructor for the class
   *
   * @param enable_ondemand_loadunload - Flag indicates if classes are to be loaded/unloaded automatically as class_loader are created and destroyed
   */
  explicit MultiLibraryClassLoader(bool enable_ondemand_loadunload);

  /**
  * @brief Virtual destructor for class
  */
  virtual ~MultiLibraryClassLoader();

  /**
   * @brief Creates an instance of an object of given class name with ancestor class Base
   * This version does not look in a specific library for the factory, but rather the first open
   * library that defines the classs
   *
   * @param Base - polymorphic type indicating base class
   * @param class_name - the name of the concrete plugin class we want to instantiate
   * @return A std::shared_ptr<Base> to newly created plugin
   */
  template<class Base>
  std::shared_ptr<Base> createInstance(const std::string & class_name)
  {
    CONSOLE_BRIDGE_logDebug(
      "class_loader::MultiLibraryClassLoader: "
      "Attempting to create instance of class type %s.",
      class_name.c_str());
    ClassLoader * loader = getClassLoaderForClass<Base>(class_name);
    if (nullptr == loader) {
      throw class_loader::CreateClassException(
              "MultiLibraryClassLoader: Could not create object of class type " +
              class_name +
              " as no factory exists for it. Make sure that the library exists and " +
              "was explicitly loaded through MultiLibraryClassLoader::loadLibrary()");
    }

    return loader->createInstance<Base>(class_name);
  }

  /**
   * @brief Creates an instance of an object of given class name with ancestor class Base
   * This version takes a specific library to make explicit the factory being used
   *
   * @param Base - polymorphic type indicating base class
   * @param class_name - the name of the concrete plugin class we want to instantiate
   * @param library_path - the library from which we want to create the plugin
   * @return A std::shared_ptr<Base> to newly created plugin
   */
  template<class Base>
  std::shared_ptr<Base> createInstance(
    const std::string & class_name, const std::string & library_path)
  {
    ClassLoader * loader = getClassLoaderForLibrary(library_path);
    if (nullptr == loader) {
      throw class_loader::NoClassLoaderExistsException(
              "Could not create instance as there is no ClassLoader in "
              "MultiLibraryClassLoader bound to library " + library_path +
              " Ensure you called MultiLibraryClassLoader::loadLibrary()");
    }
    return loader->createInstance<Base>(class_name);
  }

  /// Creates an instance of an object of given class name with ancestor class Base
  /**
   * This version does not look in a specific library for the factory, but rather the first open
   * library that defines the class
   *
   * @param Base - polymorphic type indicating base class
   * @param class_name - the name of the concrete plugin class we want to instantiate
   * @return A unique pointer to newly created plugin
   */
  template<class Base>
  ClassLoader::UniquePtr<Base> createUniqueInstance(const std::string & class_name)
  {
    CONSOLE_BRIDGE_logDebug(
      "class_loader::MultiLibraryClassLoader: Attempting to create instance of class type %s.",
      class_name.c_str());
    ClassLoader * loader = getClassLoaderForClass<Base>(class_name);
    if (nullptr == loader) {
      throw class_loader::CreateClassException(
              "MultiLibraryClassLoader: Could not create object of class type " + class_name +
              " as no factory exists for it. "
              "Make sure that the library exists and was explicitly loaded through "
              "MultiLibraryClassLoader::loadLibrary()");
    }
    return loader->createUniqueInstance<Base>(class_name);
  }

  /// Creates an instance of an object of given class name with ancestor class Base
  /**
   * This version takes a specific library to make explicit the factory being used
   *
   * @param Base - polymorphic type indicating base class
   * @param class_name - the name of the concrete plugin class we want to instantiate
   * @param library_path - the library from which we want to create the plugin
   * @return A unique pointer to newly created plugin
   */
  template<class Base>
  ClassLoader::UniquePtr<Base>
  createUniqueInstance(const std::string & class_name, const std::string & library_path)
  {
    ClassLoader * loader = getClassLoaderForLibrary(library_path);
    if (nullptr == loader) {
      throw class_loader::NoClassLoaderExistsException(
              "Could not create instance as there is no ClassLoader in "
              "MultiLibraryClassLoader bound to library " + library_path +
              " Ensure you called MultiLibraryClassLoader::loadLibrary()");
    }
    return loader->createUniqueInstance<Base>(class_name);
  }

  /**
   * @brief Creates an instance of an object of given class name with ancestor class Base
   * This version does not look in a specific library for the factory, but rather the first open
   * library that defines the class
   * This version should not be used as the plugin system cannot do automated safe loading/unloadings
   *
   * @param Base - polymorphic type indicating base class
   * @param class_name - the name of the concrete plugin class we want to instantiate
   * @return An unmanaged Base* to newly created plugin
   */
  template<class Base>
  Base * createUnmanagedInstance(const std::string & class_name)
  {
    ClassLoader * loader = getClassLoaderForClass<Base>(class_name);
    if (nullptr == loader) {
      throw class_loader::CreateClassException(
              "MultiLibraryClassLoader: Could not create class of type " + class_name);
    }
    return loader->createUnmanagedInstance<Base>(class_name);
  }

  /**
   * @brief Creates an instance of an object of given class name with ancestor class Base
   * This version takes a specific library to make explicit the factory being used
   * This version should not be used as the plugin system cannot do automated safe loading/unloadings
   *
   * @param Base - polymorphic type indicating Base class
   * @param class_name - name of class for which we want to create instance
   * @param library_path - the fully qualified path to the runtime library
   */
  template<class Base>
  Base * createUnmanagedInstance(const std::string & class_name, const std::string & library_path)
  {
    ClassLoader * loader = getClassLoaderForLibrary(library_path);
    if (nullptr == loader) {
      throw class_loader::NoClassLoaderExistsException(
              "Could not create instance as there is no ClassLoader in MultiLibraryClassLoader "
              "bound to library " + library_path +
              " Ensure you called MultiLibraryClassLoader::loadLibrary()");
    }
    return loader->createUnmanagedInstance<Base>(class_name);
  }

  /**
   * @brief Indicates if a class has been loaded and can be instantiated
   *
   * @param Base - polymorphic type indicating Base class
   * @param class_name - name of class that is be inquired about
   * @return true if loaded, false otherwise
   */
  template<class Base>
  bool isClassAvailable(const std::string & class_name) const
  {
    std::vector<std::string> available_classes = getAvailableClasses<Base>();
    return available_classes.end() != std::find(
      available_classes.begin(), available_classes.end(), class_name);
  }

  /**
   * @brief Indicates if a library has been loaded into memory
   *
   * @param library_path - The full qualified path to the runtime library
   * @return true if library is loaded, false otherwise
   */
  bool isLibraryAvailable(const std::string & library_path) const;

  /**
   * @brief Gets a list of all classes that are loaded by the class loader
   *
   * @param Base - polymorphic type indicating Base class
   * @return A vector<string> of the available classes
   */
  template<class Base>
  std::vector<std::string> getAvailableClasses() const
  {
    std::vector<std::string> available_classes;
    for (auto & loader : getAllAvailableClassLoaders()) {
      std::vector<std::string> loader_classes = loader->getAvailableClasses<Base>();
      available_classes.insert(
        available_classes.end(), loader_classes.begin(), loader_classes.end());
    }
    return available_classes;
  }

  /**
   * @brief Gets a list of all classes loaded for a particular library
   *
   * @param Base - polymorphic type indicating Base class
   * @return A vector<string> of the available classes in the passed library
   */
  template<class Base>
  std::vector<std::string> getAvailableClassesForLibrary(const std::string & library_path)
  {
    ClassLoader * loader = getClassLoaderForLibrary(library_path);
    if (nullptr == loader) {
      throw class_loader::NoClassLoaderExistsException(
              "There is no ClassLoader in MultiLibraryClassLoader bound to library " +
              library_path +
              " Ensure you called MultiLibraryClassLoader::loadLibrary()");
    }
    return loader->getAvailableClasses<Base>();
  }

  /**
   * @brief Gets a list of all libraries opened by this class loader
   *
   * @return A list of libraries opened by this class loader
   */
  std::vector<std::string> getRegisteredLibraries() const;

  /**
   * @brief Loads a library into memory for this class loader
   *
   * @param library_path - the fully qualified path to the runtime library
   */
  void loadLibrary(const std::string & library_path);

  /**
   * @brief Unloads a library for this class loader
   *
   * @param library_path - the fully qualified path to the runtime library
   * @return The number of times more unloadLibrary() has to be called for it to be unbound from
   *   this MultiLibraryClassLoader
   */
  int unloadLibrary(const std::string & library_path);

private:
  /**
   * @brief Indicates if on-demand (lazy) load/unload is enabled so libraries are loaded/unloaded
   *
   *    automatically as needed
   * @return true if ondemand load and unload is active, otherwise false
   */
  bool isOnDemandLoadUnloadEnabled() const;

  /**
   * @brief Gets a handle to the class loader corresponding to a specific runtime library
   *
   * @param library_path - the library from which we want to create the plugin
   * @return A pointer to the ClassLoader*, == nullptr if not found
   */
  ClassLoader * getClassLoaderForLibrary(const std::string & library_path);

  /// Gets a handle to the class loader corresponding to a specific class.
  /**
   * @param class_name name of class for which we want to create instance.
   * @return A pointer to the ClassLoader, or NULL if not found.
   */
  template<typename Base>
  ClassLoader * getClassLoaderForClass(const std::string & class_name)
  {
    ClassLoaderVector loaders = getAllAvailableClassLoaders();
    for (ClassLoaderVector::iterator i = loaders.begin(); i != loaders.end(); ++i) {
      if (!(*i)->isLibraryLoaded()) {
        (*i)->loadLibrary();
      }
      if ((*i)->isClassAvailable<Base>(class_name)) {
        return *i;
      }
    }
    return nullptr;
  }

  /**
   * @brief Gets all class loaders loaded within scope
   *
   * @return vector with available ClassLoader pointers
   */
  ClassLoaderVector getAllAvailableClassLoaders() const;

  /**
   * @brief Destroys all ClassLoaders
   */
  void shutdownAllClassLoaders();

  MultiLibraryClassLoaderImpl * impl_;
};


}  // namespace class_loader
#endif  // CLASS_LOADER__MULTI_LIBRARY_CLASS_LOADER_HPP_