// Copyright Contributors to the DNF5 project.
// Copyright Contributors to the libdnf project.
// SPDX-License-Identifier: LGPL-2.1-or-later
//
// This file is part of libdnf: https://github.com/rpm-software-management/libdnf/
//
// Libdnf is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 2.1 of the License, or
// (at your option) any later version.
//
// Libdnf is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with libdnf.  If not, see <https://www.gnu.org/licenses/>.

#ifndef LIBDNF5_PLUGIN_PLUGINS_HPP
#define LIBDNF5_PLUGIN_PLUGINS_HPP

#include "libdnf5/common/exception.hpp"
#include "libdnf5/conf/config_parser.hpp"
#include "libdnf5/plugin/iplugin.hpp"

#include <filesystem>
#include <memory>
#include <string>
#include <vector>


namespace libdnf5::plugin {

class PluginError : public Error {
public:
    using Error::Error;
    const char * get_domain_name() const noexcept override { return "libdnf5::plugin"; }
    const char * get_name() const noexcept override { return "PluginError"; }
};


class Plugin {
public:
    Plugin(IPlugin & iplugin_instance, ConfigParser && parser);
    virtual ~Plugin();

    Plugin(const Plugin &) = delete;
    Plugin(Plugin &&) = delete;
    Plugin & operator=(const Plugin &) = delete;
    Plugin & operator=(Plugin &&) = delete;

    IPlugin * get_iplugin() const noexcept;
    ConfigParser & get_config_parser() noexcept;

    void set_enabled(bool enabled) noexcept;
    bool get_enabled() const noexcept;

    void init();
    void pre_base_setup();
    void post_base_setup();
    void repos_configured();
    void repos_loaded();
    void pre_add_cmdline_packages(const std::vector<std::string> & paths);
    void post_add_cmdline_packages();
    void goal_resolved(const libdnf5::base::Transaction & transaction);
    void pre_transaction(const libdnf5::base::Transaction & transaction);
    void post_transaction(const libdnf5::base::Transaction & transaction);
    void finish() noexcept;

protected:
    Plugin(ConfigParser && parser) : cfg_parser(std::move(parser)) {}
    IPlugin * iplugin_instance{nullptr};
    ConfigParser cfg_parser;
    bool enabled{true};
};


/// Plugin manager
class Plugins {
public:
    Plugins(Base & base);
    ~Plugins();

    /// Registers the plugin passed by the argument.
    void register_plugin(std::unique_ptr<Plugin> && plugin);

    /// Loads plugins defined by configuration files in the directories.
    void load_plugins(const std::vector<std::filesystem::path> & config_dirs);

    /// Returns the number of registered plugins.
    size_t count() const noexcept;

    /// Call init of all allowed plugins.
    bool init();

    /// Call hook of all allowed plugins.
    void pre_base_setup();

    void post_base_setup();

    void repos_configured();

    void repos_loaded();

    void pre_add_cmdline_packages(const std::vector<std::string> & paths);

    void post_add_cmdline_packages();

    void goal_resolved(const libdnf5::base::Transaction & transaction);

    void pre_transaction(const libdnf5::base::Transaction & transaction);

    void post_transaction(const libdnf5::base::Transaction & transaction);

    /// Call finish of all allowed plugins in reverse order.
    void finish() noexcept;

private:
    std::string find_plugin_library(const std::string & plugin_name);

    /// Loads the plugin from the library defined by the file path.
    void load_plugin_library(ConfigParser && parser, const std::string & file_path, const std::string & plugin_name);

    Base * base;
    std::vector<std::unique_ptr<Plugin>> plugins;
};


inline Plugin::Plugin(IPlugin & iplugin_instance, ConfigParser && parser)
    : iplugin_instance{&iplugin_instance},
      cfg_parser(std::move(parser)) {}

inline Plugin::~Plugin() {
    finish();
}

inline IPlugin * Plugin::get_iplugin() const noexcept {
    return iplugin_instance;
}

inline ConfigParser & Plugin::get_config_parser() noexcept {
    return cfg_parser;
}

inline void Plugin::set_enabled(bool enabled) noexcept {
    this->enabled = enabled;
}

inline bool Plugin::get_enabled() const noexcept {
    return enabled;
}

inline void Plugin::init() {
    if (iplugin_instance) {
        iplugin_instance->init();
    }
}

inline void Plugin::pre_base_setup() {
    if (iplugin_instance) {
        iplugin_instance->pre_base_setup();
    }
}

inline void Plugin::post_base_setup() {
    if (iplugin_instance) {
        iplugin_instance->post_base_setup();
    }
}

inline void Plugin::repos_configured() {
    if (iplugin_instance) {
        iplugin_instance->repos_configured();
    }
}

inline void Plugin::repos_loaded() {
    if (iplugin_instance) {
        iplugin_instance->repos_loaded();
    }
}

inline void Plugin::pre_add_cmdline_packages(const std::vector<std::string> & paths) {
    if (iplugin_instance) {
        iplugin_instance->pre_add_cmdline_packages(paths);
    }
}

inline void Plugin::post_add_cmdline_packages() {
    if (iplugin_instance) {
        iplugin_instance->post_add_cmdline_packages();
    }
}

inline void Plugin::goal_resolved(const libdnf5::base::Transaction & transaction) {
    if (iplugin_instance) {
        if (auto iplugin2_1_instance = dynamic_cast<IPlugin2_1 *>(iplugin_instance)) {
            iplugin2_1_instance->goal_resolved(transaction);
        }
    }
}

inline void Plugin::pre_transaction(const libdnf5::base::Transaction & transaction) {
    if (iplugin_instance) {
        iplugin_instance->pre_transaction(transaction);
    }
}

inline void Plugin::post_transaction(const libdnf5::base::Transaction & transaction) {
    if (iplugin_instance) {
        iplugin_instance->post_transaction(transaction);
    }
}

inline void Plugin::finish() noexcept {
    if (iplugin_instance) {
        iplugin_instance->finish();
    }
}

inline Plugins::Plugins(Base & base) : base(&base) {}

inline size_t Plugins::count() const noexcept {
    return plugins.size();
}

}  // namespace libdnf5::plugin

#endif