// 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/>.

#include "libdnf5/comps/environment/environment.hpp"

#include "solv/pool.hpp"
#include "utils/xml.hpp"

#include "libdnf5/base/base.hpp"
#include "libdnf5/base/base_weak.hpp"
#include "libdnf5/comps/environment/query.hpp"
#include "libdnf5/utils/bgettext/bgettext-mark-domain.h"

extern "C" {
#include <solv/dataiterator.h>
#include <solv/knownid.h>
#include <solv/pool.h>
#include <solv/solvable.h>
}

#include <libxml/tree.h>
#include <limits.h>

#include <set>
#include <string>
#include <string_view>
#include <vector>


namespace libdnf5::comps {

class Environment::Impl {
public:
    explicit Impl(const libdnf5::BaseWeakPtr & base) : base(base) {}

private:
    friend Environment;

    libdnf5::BaseWeakPtr base;

    // Corresponds to solvable ids for this environment (libsolv doesn't merge groups, so there are multiple solvables
    // for one environmentid).
    // The order is given by the repoids of the originating repositories. The repoids that come later in the alphabet
    // are preferred (e.g. the description is taken from solvable from repository "B", even though there is a different
    // description in repository "A"). A notable case are repositories "fedora" and "updates" where the "updates"
    // repository is preferred, and coincidentally, this is what we want, because "updates" contains more up-to-date
    // definitions.
    std::vector<EnvironmentId> environment_ids;

    std::vector<std::string> groups;
    std::vector<std::string> optional_groups;
};


Environment::Environment(const libdnf5::BaseWeakPtr & base) : p_impl(std::make_unique<Impl>(base)) {}

Environment::Environment(libdnf5::Base & base) : Environment(base.get_weak_ptr()) {}

Environment::~Environment() = default;

Environment::Environment(const Environment & src) : p_impl(new Impl(*src.p_impl)) {}
Environment::Environment(Environment && src) noexcept = default;

Environment & Environment::operator=(const Environment & src) {
    if (this != &src) {
        if (p_impl) {
            *p_impl = *src.p_impl;
        } else {
            p_impl = std::make_unique<Impl>(*src.p_impl);
        }
    }

    return *this;
}
Environment & Environment::operator=(Environment && src) noexcept = default;

Environment & Environment::operator+=(const Environment & rhs) {
    p_impl->environment_ids.insert(
        p_impl->environment_ids.begin(), rhs.p_impl->environment_ids.begin(), rhs.p_impl->environment_ids.end());
    return *this;
}

bool Environment::operator==(const Environment & rhs) const noexcept {
    return p_impl->environment_ids == rhs.p_impl->environment_ids && p_impl->base == rhs.p_impl->base;
}

bool Environment::operator!=(const Environment & rhs) const noexcept {
    return p_impl->environment_ids != rhs.p_impl->environment_ids || p_impl->base != rhs.p_impl->base;
}

bool Environment::operator<(const Environment & rhs) const {
    return get_environmentid() < rhs.get_environmentid() || get_repos() < rhs.get_repos();
}

libdnf5::BaseWeakPtr Environment::get_base() {
    return p_impl->base;
}

std::string Environment::get_environmentid() const {
    return solv::CompsPool::split_solvable_name(
               get_comps_pool(p_impl->base).lookup_first_id_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_NAME))
        .second;
}


std::string Environment::get_name() const {
    return get_comps_pool(p_impl->base).lookup_first_id_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_SUMMARY);
}


std::string Environment::get_description() const {
    return get_comps_pool(p_impl->base)
        .lookup_first_id_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_DESCRIPTION);
}


std::string Environment::get_translated_name(const char * lang) const {
    return get_comps_pool(p_impl->base)
        .get_translated_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_SUMMARY, lang);
}


// TODO(pkratoch): Test this
std::string Environment::get_translated_name() const {
    return get_comps_pool(p_impl->base).get_translated_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_SUMMARY);
}


std::string Environment::get_translated_description(const char * lang) const {
    return get_comps_pool(p_impl->base)
        .get_translated_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_DESCRIPTION, lang);
}


std::string Environment::get_translated_description() const {
    return get_comps_pool(p_impl->base)
        .get_translated_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_DESCRIPTION);
}


std::string Environment::get_order() const {
    return get_comps_pool(p_impl->base).lookup_first_id_str<EnvironmentId>(p_impl->environment_ids, SOLVABLE_ORDER);
}


int Environment::get_order_int() const {
    try {
        return std::stoi(get_order());
    } catch (const std::invalid_argument &) {
        return INT_MAX;
    } catch (const std::out_of_range &) {
        return INT_MAX;
    }
}


std::vector<std::string> load_groups_from_pool(
    libdnf5::solv::CompsPool & pool, const std::vector<EnvironmentId> & environment_ids, bool required = true) {
    std::set<std::string> groups;
    std::string_view group_solvable_name;

    for (auto environment_id : environment_ids) {
        Solvable * solvable = pool.id2solvable(environment_id.id);
        Offset offset;
        if (required) {
            offset = solvable->dep_requires;
        } else {
            offset = solvable->dep_suggests;
        }

        if (offset) {
            for (Id * r_id = solvable->repo->idarraydata + offset; *r_id; ++r_id) {
                group_solvable_name = pool.id2str(*r_id);
                groups.emplace(solv::CompsPool::split_solvable_name(group_solvable_name).second);
            }
        }
    }

    return std::vector(groups.begin(), groups.end());
}


std::vector<std::string> Environment::get_groups() {
    if (p_impl->groups.empty()) {
        p_impl->groups = load_groups_from_pool(get_comps_pool(p_impl->base), p_impl->environment_ids);
    }
    return p_impl->groups;
}


std::vector<std::string> Environment::get_optional_groups() {
    if (p_impl->optional_groups.empty()) {
        p_impl->optional_groups = load_groups_from_pool(get_comps_pool(p_impl->base), p_impl->environment_ids, false);
    }
    return p_impl->optional_groups;
}

libdnf5::transaction::TransactionItemReason Environment::get_reason() const {
    comps::EnvironmentQuery installed_query(p_impl->base);
    installed_query.filter_installed(true);
    installed_query.filter_environmentid(get_environmentid());
    if (!installed_query.empty()) {
        auto reason = p_impl->base->p_impl->get_system_state().get_environment_reason(get_environmentid());

        if (reason == libdnf5::transaction::TransactionItemReason::NONE) {
            return libdnf5::transaction::TransactionItemReason::EXTERNAL_USER;
        }

        return reason;
    }

    return libdnf5::transaction::TransactionItemReason::NONE;
}


std::set<std::string> Environment::get_repos() const {
    std::set<std::string> result;
    for (EnvironmentId environment_id : p_impl->environment_ids) {
        Solvable * solvable = get_comps_pool(p_impl->base).id2solvable(environment_id.id);
        result.emplace(solvable->repo->name);
    }
    return result;
}


bool Environment::get_installed() const {
    auto repos = get_repos();
    return repos.find("@System") != repos.end();
}


void Environment::serialize(const std::string & path) {
    // Create doc with root node "comps"
    xmlDocPtr doc = xmlNewDoc(BAD_CAST "1.0");
    xmlNodePtr node_comps = xmlNewNode(NULL, BAD_CAST "comps");
    xmlDocSetRootElement(doc, node_comps);

    // Create "environment" node
    xmlNodePtr node_environment = xmlNewNode(NULL, BAD_CAST "environment");
    xmlAddChild(node_comps, node_environment);

    // Add id, name, description, display_order
    utils::xml::add_subnode_with_text(node_environment, "id", get_environmentid());
    utils::xml::add_subnode_with_text(node_environment, "name", get_name());
    utils::xml::add_subnode_with_text(node_environment, "description", get_description());
    utils::xml::add_subnode_with_text(node_environment, "display_order", get_order());

    // Add translations
    std::set<std::string> name_langs;
    std::set<std::string> description_langs;
    std::string summary_prefix = "solvable:summary:";
    std::string description_prefix = "solvable:description:";
    std::string keyname;
    std::string lang;
    xmlNodePtr node;

    libdnf5::solv::CompsPool & pool = get_comps_pool(p_impl->base);

    for (auto environment_id : p_impl->environment_ids) {
        Dataiterator di;
        dataiterator_init(&di, *pool, 0, environment_id.id, 0, 0, 0);
        // Iterate over all data in the environment solvable
        while (dataiterator_step(&di) != 0) {
            // If the content is NULL, skip
            if (!di.kv.str) {
                continue;
            }
            keyname = pool.id2str(di.key->name);
            // If keyname starts with "solvable:summary:", it's a name translation
            if (keyname.rfind(summary_prefix, 0) == 0) {
                lang = keyname.substr(summary_prefix.length());
                // Add the lang into the set
                // If it's successful (wasn't already present), create an XML node for this translation
                if (name_langs.insert(lang).second) {
                    node = utils::xml::add_subnode_with_text(node_environment, "name", std::string(di.kv.str));
                    xmlNewProp(node, BAD_CAST "xml:lang", BAD_CAST lang.c_str());
                }
            }
            // If keyname starts with "solvable:description:", it's a description translation
            else if (keyname.rfind(description_prefix, 0) == 0) {
                lang = keyname.substr(description_prefix.length());
                // Add the lang into the set
                // If it's successful (wasn't already present), create an XML node for this translation
                if (description_langs.insert(lang).second) {
                    node = utils::xml::add_subnode_with_text(node_environment, "description", std::string(di.kv.str));
                    xmlNewProp(node, BAD_CAST "xml:lang", BAD_CAST lang.c_str());
                }
            }
        }
        dataiterator_free(&di);
    }

    // Add grouplist
    xmlNodePtr node_grouplist = xmlNewNode(NULL, BAD_CAST "grouplist");
    xmlAddChild(node_environment, node_grouplist);
    for (const auto & group : get_groups()) {
        // Create an XML node for this package
        node = utils::xml::add_subnode_with_text(node_grouplist, "groupid", group);
    }
    xmlNodePtr node_optionlist = xmlNewNode(NULL, BAD_CAST "optionlist");
    xmlAddChild(node_environment, node_optionlist);
    for (const auto & group : get_optional_groups()) {
        // Create an XML node for this package
        node = utils::xml::add_subnode_with_text(node_optionlist, "groupid", group);
    }

    // Save the document
    if (xmlSaveFormatFileEnc(path.c_str(), doc, "utf-8", 1) == -1) {
        throw utils::xml::XMLSaveError(M_("failed to save xml document for comps"));
    }

    // Memory free
    xmlFreeDoc(doc);
}

void Environment::add_environment_id(const EnvironmentId & environment_id) {
    p_impl->environment_ids.push_back(environment_id);
}

}  // namespace libdnf5::comps