// 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_BASE_TRANSACTION_HPP
#define LIBDNF5_BASE_TRANSACTION_HPP

#include "transaction_errors.hpp"

#include "libdnf5/base/base_weak.hpp"
#include "libdnf5/base/goal_elements.hpp"
#include "libdnf5/base/log_event.hpp"
#include "libdnf5/base/solver_problems.hpp"
#include "libdnf5/common/proc.hpp"
#include "libdnf5/defs.h"
#include "libdnf5/rpm/transaction_callbacks.hpp"

#include <optional>


namespace libdnf5::rpm {
class KeyInfo;
}  // namespace libdnf5::rpm


namespace libdnf5::base {

class TransactionGroup;
class TransactionEnvironment;
class TransactionModule;
class TransactionPackage;


class LIBDNF_API Transaction {
public:
    /// enum representing Transaction run result
    enum class TransactionRunResult {
        SUCCESS,
        ERROR_RERUN,
        ERROR_RESOLVE,
        ERROR_LOCK,
        ERROR_CHECK,
        ERROR_RPM_RUN,
        ERROR_GPG_CHECK,
    };

    Transaction(const Transaction & transaction);
    Transaction(Transaction && transaction);
    ~Transaction();

    /// Return basic overview about result of resolving transaction.
    /// To get complete information, use get_resolve_logs().
    libdnf5::GoalProblem get_problems();

    /// Returns information about resolvement of Goal.
    /// @return A vector of LogEvent instances.
    const std::vector<libdnf5::base::LogEvent> & get_resolve_logs() const;

    /// Returns information about resolvement of Goal as a list of printable messages
    /// @return A vector of string representations of problems.
    std::vector<std::string> get_resolve_logs_as_strings() const;

    /// @return the transaction packages.
    // TODO(jrohel): Return reference instead of copy?
    std::vector<libdnf5::base::TransactionPackage> get_transaction_packages() const;

    /// @return the number of transaction packages.
    std::size_t get_transaction_packages_count() const;

    /// @return the transaction groups.
    std::vector<libdnf5::base::TransactionGroup> & get_transaction_groups() const;

    /// @return the transaction modules.
    std::vector<libdnf5::base::TransactionModule> & get_transaction_modules() const;

    /// @return environmental groups that are part of the transaction.
    std::vector<libdnf5::base::TransactionEnvironment> & get_transaction_environments() const;

    /// @return list of packages skipped due to broken dependencies
    std::vector<libdnf5::rpm::Package> get_broken_dependency_packages() const;

    /// @return list of packages skipped due to conflicts
    std::vector<libdnf5::rpm::Package> get_conflicting_packages() const;

    /// @return `true` if the transaction is empty.
    bool empty() const;

    /// Download all inbound packages (packages that are being installed on the
    /// system). Fails immediately on the first package download failure. Will
    /// try to resume downloads of any partially-downloaded RPMs.
    ///
    /// The destination directory for downloaded RPMs is taken from the `destdir`
    /// configuration option. If it's not specified, the standard location of
    /// repo cachedir/packages is used.
    void download();

    /// Check the transaction by running it with RPMTRANS_FLAG_TEST. The import
    /// of any necessary public keys will be requested, and transaction checks
    /// will be performed, but no changes to the installed package set will be
    /// made. These checks are performed automatically by run(); it is
    /// redundant to call test() before calling run().
    /// @return An enum describing the result of the transaction
    TransactionRunResult test();

    /// @brief Prepare, check and run the transaction.
    ///
    /// All the transaction metadata that was set (`description`, `user_id` or `comment`)
    /// is stored in the history database.
    ///
    /// To watch progress or trigger actions during specific transactions events,
    /// setup the `callbacks` object.
    ///
    /// After a successful transaction, any temporarily downloaded packages are removed
    /// if the 'keepcache' option is set to 'false' and the transaction involved an inbound action.
    /// Otherwise, the packages are preserved on the disk.
    ///
    /// @return An enum describing the result of running the transaction.
    TransactionRunResult run();

    /// @brief Setup callbacks to be called during rpm transaction.
    /// @param callbacks Implemented callbacks object.
    void set_callbacks(std::unique_ptr<libdnf5::rpm::TransactionCallbacks> && callbacks);

    /// @brief Setup a description of the transaction.
    /// @param description Value could be the console command for CLI or verbose description for API usage.
    void set_description(const std::string & description);

    /// @brief Setup the id of the user that started the transaction. If not set, current login user UID is used.
    /// @param user_id UID value.
    void set_user_id(const uint32_t user_id);

    /// @brief Setup a comment to store in the history database along with the transaction.
    /// @param comment Any string value.
    void set_comment(const std::string & comment);

    /// Return string representation of the TransactionRunResult enum
    static std::string transaction_result_to_string(const TransactionRunResult result);

    /// Retrieve list of problems that occurred during transaction run attempt
    std::vector<std::string> get_transaction_problems() const noexcept;

    /// @brief Check signatures of packages in the resolved transaction.
    ///
    /// @return True if all packages have correct signatures or checking is turned off with `pkg_gpgcheck` option,
    /// otherwise false. More info about occurred problems can be retrieved using the `get_gpg_signature_problems`
    /// method.
    bool check_gpg_signatures();

    /// Retrieve a list of the problems that occurred during `check_gpg_signatures` procedure.
    std::vector<std::string> get_gpg_signature_problems() const noexcept;

    /// @warning This method is experimental/unstable and should not be relied on. It may be removed without warning
    /// Serialize the transaction into a json data format which can be later loaded
    /// into a `libdnf5::Goal` and replayed.
    /// @param packages_path If provided it is assumed all packages in this transaction are present there and
    ///                      the resulting serialized transaction will contain paths to those packages.
    /// @param comps_path If provided it is assumed all comps in this transaction are present there and
    ///                   the resulting serialized transaction will contain paths to those xml comps files
    ///                   (they can be stored using the `store_comps` method).
    /// @param repo_prefix If provided each repository id (except for @System repo) used in this transaction
    ///                    will be wrapped in brackets and prefix by repo_prefix.
    std::string serialize(
        const std::filesystem::path & packages_path = "",
        const std::filesystem::path & comps_path = "",
        const std::string repo_prefix = "") const;

    /// @warning This method is experimental/unstable and should not be relied on. It may be removed without warning
    /// Store each group and environment in this transaction as a separate xml file in the
    /// specified path.
    void store_comps(const std::filesystem::path & comps_path) const;

    /// Set whether local packages should be copied to the destination directory during the download().
    ///
    /// Default: false
    void set_download_local_pkgs(bool value);
    bool get_download_local_pkgs() const noexcept;

    /// Retrieve output of the last executed rpm scriptlet.
    std::string get_last_script_output();

    /// Retrieve captured RPM log messages
    std::vector<std::string> get_rpm_messages();

private:
    friend class TransactionEnvironment;
    friend class TransactionGroup;
    friend class TransactionModule;
    friend class TransactionPackage;
    friend class libdnf5::Goal;
    friend class libdnf5::rpm::
        Transaction;  // to access clear_last_script_output() from the rpm transaction SCRIPT_START callback

    LIBDNF_LOCAL Transaction(const libdnf5::BaseWeakPtr & base);

    class LIBDNF_LOCAL Impl;
    std::unique_ptr<Impl> p_impl;

    std::unique_ptr<libdnf5::rpm::TransactionCallbacks> callbacks;
    std::optional<uint32_t> user_id;
    std::string comment;
    std::string description;

    /// Clear the recorded last scriptlet output
    LIBDNF_LOCAL void clear_last_script_output();

    /// Store captured RPM log messages
    LIBDNF_LOCAL void set_rpm_messages(std::vector<std::string> && rpm_messages);
};

}  // namespace libdnf5::base

#endif  // LIBDNF5_BASE_TRANSACTION_HPP