/* apt-utils.cpp
 *
 * Copyright (c) 2009 Daniel Nicoletti <dantti12@gmail.com>
 * Copyright (c) 2014-2022 Matthias Klumpp <mak@debian.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include "apt-utils.h"

#include <apt-pkg/fileutl.h>
#include <apt-pkg/error.h>
#include <apt-pkg/pkgsystem.h>
#include <apt-pkg/version.h>
#include <apt-pkg/acquire-item.h>
#include <glib/gstdio.h>

#include <ctime>
#include <fstream>
#include <iomanip>
#include <regex>

PkGroupEnum get_enum_group(string group)
{
    if (group.compare("admin") == 0) {
        return PK_GROUP_ENUM_ADMIN_TOOLS;
    } else if (group.compare("base") == 0) {
        return PK_GROUP_ENUM_SYSTEM;
    } else if (group.compare("cli-mono") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("comm") == 0) {
        return PK_GROUP_ENUM_COMMUNICATION;
    } else if (group.compare("database") == 0) {
        return PK_GROUP_ENUM_ADMIN_TOOLS;
    } else if (group.compare("debug") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("devel") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("doc") == 0) {
        return PK_GROUP_ENUM_DOCUMENTATION;
    } else if (group.compare("editors") == 0) {
        return PK_GROUP_ENUM_PUBLISHING;
    } else if (group.compare("education") == 0) {
        return PK_GROUP_ENUM_EDUCATION;
    } else if (group.compare("electronics") == 0) {
        return PK_GROUP_ENUM_ELECTRONICS;
    } else if (group.compare("embedded") == 0) {
        return PK_GROUP_ENUM_SYSTEM;
    } else if (group.compare("fonts") == 0) {
        return PK_GROUP_ENUM_FONTS;
    } else if (group.compare("games") == 0) {
        return PK_GROUP_ENUM_GAMES;
    } else if (group.compare("gnome") == 0) {
        return PK_GROUP_ENUM_DESKTOP_GNOME;
    } else if (group.compare("gnu-r") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("gnustep") == 0) {
        return PK_GROUP_ENUM_DESKTOP_OTHER;
    } else if (group.compare("golang") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("graphics") == 0) {
        return PK_GROUP_ENUM_GRAPHICS;
    } else if (group.compare("hamradio") == 0) {
        return PK_GROUP_ENUM_COMMUNICATION;
    } else if (group.compare("haskell") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("httpd") == 0) {
        return PK_GROUP_ENUM_SERVERS;
    } else if (group.compare("interpreters") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("introspection") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("java") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("javascript") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("kde") == 0) {
        return PK_GROUP_ENUM_DESKTOP_KDE;
    } else if (group.compare("kernel") == 0) {
        return PK_GROUP_ENUM_SYSTEM;
    } else if (group.compare("libdevel") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("libs") == 0) {
        return PK_GROUP_ENUM_SYSTEM;
    } else if (group.compare("lisp") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("mail") == 0) {
        return PK_GROUP_ENUM_INTERNET;
    } else if (group.compare("math") == 0) {
        return PK_GROUP_ENUM_SCIENCE;
    } else if (group.compare("misc") == 0) {
        return PK_GROUP_ENUM_OTHER;
    } else if (group.compare("net") == 0) {
        return PK_GROUP_ENUM_NETWORK;
    } else if (group.compare("news") == 0) {
        return PK_GROUP_ENUM_INTERNET;
    } else if (group.compare("ocaml") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("oldlibs") == 0) {
        return PK_GROUP_ENUM_LEGACY;
    } else if (group.compare("otherosfs") == 0) {
        return PK_GROUP_ENUM_SYSTEM;
    } else if (group.compare("perl") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("php") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("python") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("ruby") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("rust") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("science") == 0) {
        return PK_GROUP_ENUM_SCIENCE;
    } else if (group.compare("shells") == 0) {
        return PK_GROUP_ENUM_SYSTEM;
    } else if (group.compare("sound") == 0) {
        return PK_GROUP_ENUM_MULTIMEDIA;
    } else if (group.compare("tex") == 0) {
        return PK_GROUP_ENUM_PUBLISHING;
    } else if (group.compare("text") == 0) {
        return PK_GROUP_ENUM_PUBLISHING;
    } else if (group.compare("utils") == 0) {
        return PK_GROUP_ENUM_ACCESSORIES;
    } else if (group.compare("vcs") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("video") == 0) {
        return PK_GROUP_ENUM_MULTIMEDIA;
    } else if (group.compare("web") == 0) {
        return PK_GROUP_ENUM_INTERNET;
    } else if (group.compare("x11") == 0) {
        return PK_GROUP_ENUM_DESKTOP_OTHER;
    } else if (group.compare("xfce") == 0) {
        return PK_GROUP_ENUM_DESKTOP_XFCE;
    } else if (group.compare("zope") == 0) {
        return PK_GROUP_ENUM_PROGRAMMING;
    } else if (group.compare("alien") == 0) {
        return PK_GROUP_ENUM_UNKNOWN; // FIXME alien is an unknown group?
    } else if (group.compare("translations") == 0) {
        return PK_GROUP_ENUM_LOCALIZATION;
    } else if (group.compare("metapackages") == 0) {
        return PK_GROUP_ENUM_COLLECTIONS;
    } else {
        return PK_GROUP_ENUM_UNKNOWN;
    }
}

string fetchChangelogData(
    AptCacheFile &CacheFile,
    pkgAcquire &Fetcher,
    pkgCache::VerIterator Ver,
    pkgCache::VerIterator currver,
    string *update_text,
    string *updated,
    string *issued)
{
    string changelog;

    pkgAcqChangelog *c = new pkgAcqChangelog(&Fetcher, Ver);

    // try downloading it, if that fails, try third-party-changelogs location
    // FIXME: Fetcher.Run() is "Continue" even if I get a 404?!?
    Fetcher.Run();

    // error
    pkgRecords Recs(CacheFile);
    pkgCache::PkgIterator Pkg = Ver.ParentPkg();
    pkgRecords::Parser &rec = Recs.Lookup(Ver.FileList());
    string srcpkg = rec.SourcePkg().empty() ? Pkg.Name() : rec.SourcePkg();
    changelog = "Changelog for this version is not yet available";

    // return empty string if we don't have a file to read
    if (!FileExists(c->DestFile)) {
        return changelog;
    }

    if (_error->PendingError()) {
        return changelog;
    }

    ifstream in(c->DestFile.c_str());
    string line;
    g_autoptr(GRegex) regexVer = NULL;
    regexVer = g_regex_new(
        "(?'source'.+) \\((?'version'.*)\\) "
        "(?'dist'.+); urgency=(?'urgency'.+)",
        G_REGEX_CASELESS,
        G_REGEX_MATCH_ANCHORED,
        0);
    g_autoptr(GRegex) regexDate = NULL;
    regexDate = g_regex_new(
        "^ -- (?'maintainer'.+) (?'mail'<.+>)  (?'date'.+)$", G_REGEX_CASELESS, G_REGEX_MATCH_ANCHORED, 0);

    changelog = "";
    while (getline(in, line)) {
        // we don't want the additional whitespace, because it can confuse
        // some markdown parsers used by client tools
        if (starts_with(line, "  "))
            line.erase(0, 1);
        // no need to free str later, it is allocated in a static buffer
        const char *str = toUtf8(line.c_str());
        if (strcmp(str, "") == 0) {
            changelog.append("\n");
            continue;
        }

        if (starts_with(str, srcpkg.c_str())) {
            // Check to see if the the text isn't about the current package,
            // otherwise add a == version ==
            GMatchInfo *match_info;
            if (g_regex_match(regexVer, str, G_REGEX_MATCH_ANCHORED, &match_info)) {
                gchar *version;
                version = g_match_info_fetch_named(match_info, "version");

                // Compare if the current version is shown in the changelog, to not
                // display old changelog information
                if (_system != 0
                    && _system->VS->DoCmpVersion(
                           version,
                           version + strlen(version),
                           currver.SourceVerStr(),
                           currver.SourceVerStr() + strlen(currver.SourceVerStr()))
                           <= 0) {
                    g_free(version);
                    break;
                } else {
                    if (!update_text->empty()) {
                        update_text->append("\n\n");
                    }
                    update_text->append(" == ");
                    update_text->append(version);
                    update_text->append(" ==");
                    g_free(version);
                }
            }
            g_match_info_free(match_info);
        } else if (starts_with(str, " --")) {
            // Parse the text to know when the update was issued,
            // and when it got updated
            GMatchInfo *match_info;
            if (g_regex_match(regexDate, str, G_REGEX_MATCH_ANCHORED, &match_info)) {
                const string date = g_match_info_fetch_named(match_info, "date");
                const string date_iso = changelogDateToIso8601(date);
                if (!date_iso.empty()) {
                    *issued = date_iso;
                    if (updated->empty()) {
                        *updated = date_iso;
                    }
                }
            }
            g_match_info_free(match_info);

            update_text->append("\n\n");
            update_text->append(str);
        } else {
            update_text->append("\n");
            update_text->append(str);
        }

        changelog.append(str);
        changelog.append("\n");
    }

    changelog.erase(changelog.find_last_not_of(" \t\n") + 1);
    return changelog;
}

GPtrArray *getCVEUrls(const string &changelog)
{
    GPtrArray *cve_urls = g_ptr_array_new();

    // Regular expression to find cve references
    GRegex *regex;
    GMatchInfo *match_info;
    regex = g_regex_new("CVE-\\d{4}-\\d{4,}", G_REGEX_CASELESS, G_REGEX_MATCH_NEWLINE_ANY, 0);
    g_regex_match(regex, changelog.c_str(), G_REGEX_MATCH_NEWLINE_ANY, &match_info);
    while (g_match_info_matches(match_info)) {
        gchar *cve = g_match_info_fetch(match_info, 0);
        gchar *cveLink;

        cveLink = g_strdup_printf("https://web.nvd.nist.gov/view/vuln/detail?vulnId=%s", cve);
        g_ptr_array_add(cve_urls, (gpointer)cveLink);

        g_free(cve);
        g_match_info_next(match_info, NULL);
    }
    g_match_info_free(match_info);
    g_regex_unref(regex);

    // NULL terminate
    g_ptr_array_add(cve_urls, NULL);

    return cve_urls;
}

GPtrArray *getBugzillaUrls(const string &changelog)
{
    GPtrArray *bugzilla_urls = g_ptr_array_new();

    // Matches Ubuntu bugs
    GRegex *regex;
    GMatchInfo *match_info;
    regex = g_regex_new("LP:\\s+(?:[,\\s*]?#(?'bug'\\d+))*", G_REGEX_CASELESS, G_REGEX_MATCH_NEWLINE_ANY, 0);
    g_regex_match(regex, changelog.c_str(), G_REGEX_MATCH_NEWLINE_ANY, &match_info);
    while (g_match_info_matches(match_info)) {
        gchar *bug = g_match_info_fetch_named(match_info, "bug");
        gchar *bugLink;

        bugLink = g_strdup_printf("https://bugs.launchpad.net/bugs/%s", bug);
        g_ptr_array_add(bugzilla_urls, (gpointer)bugLink);

        g_free(bug);
        g_match_info_next(match_info, NULL);
    }
    g_match_info_free(match_info);
    g_regex_unref(regex);

    // Debian bugs
    // Regular expressions to detect bug numbers in changelogs according to the
    // Debian Policy Chapter 4.4. For details see the footnote 15:
    // https://www.debian.org/doc/debian-policy/footnotes.html#f15
    // /closes:\s*(?:bug)?\#?\s?\d+(?:,\s*(?:bug)?\#?\s?\d+)*/i
    regex = g_regex_new(
        "closes:\\s*(?:bug)?\\#?\\s?(?'bug1'\\d+)(?:,\\s*(?:bug)?\\#?\\s?(?'bug2'\\d+))*",
        G_REGEX_CASELESS,
        G_REGEX_MATCH_NEWLINE_ANY,
        0);
    g_regex_match(regex, changelog.c_str(), G_REGEX_MATCH_NEWLINE_ANY, &match_info);
    while (g_match_info_matches(match_info)) {
        gchar *bug1 = g_match_info_fetch_named(match_info, "bug1");
        gchar *bugLink1;

        bugLink1 = g_strdup_printf("https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=%s", bug1);
        g_ptr_array_add(bugzilla_urls, (gpointer)bugLink1);

        g_free(bug1);

        gchar *bug2 = g_match_info_fetch_named(match_info, "bug2");
        if (bug2 != NULL && bug2[0] != '\0') {
            gchar *bugLink2;

            bugLink2 = g_strdup_printf("https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=%s", bug2);
            g_ptr_array_add(bugzilla_urls, (gpointer)bugLink2);

            g_free(bug2);
        }

        g_match_info_next(match_info, NULL);
    }
    g_match_info_free(match_info);
    g_regex_unref(regex);

    // NULL terminate
    g_ptr_array_add(bugzilla_urls, NULL);

    return bugzilla_urls;
}

bool ends_with(const string &str, const char *end)
{
    size_t endSize = strlen(end);
    return str.size() >= endSize && (memcmp(str.data() + str.size() - endSize, end, endSize) == 0);
}

bool starts_with(const string &str, const char *start)
{
    size_t startSize = strlen(start);
    return str.size() >= startSize && (strncmp(str.data(), start, startSize) == 0);
}

bool utilRestartRequired(const string &packageName)
{
    if (starts_with(packageName, "linux-image-") || starts_with(packageName, "nvidia-") || packageName == "libc6"
        || packageName == "dbus" || packageName == "dbus-broker") {
        return true;
    }
    return false;
}

string utilBuildPackageOriginId(pkgCache::VerFileIterator vf)
{
    if (vf.File().Origin() == nullptr)
        return string("local");
    if (vf.File().Archive() == nullptr)
        return string("local");
    if (vf.File().Component() == nullptr)
        return string("invalid");

    // https://wiki.debian.org/DebianRepository/Format
    // Optional field indicating the origin of the repository, a single line of free form text.
    // e.g. "Debian" or "Google Inc."
    auto origin = string(vf.File().Origin());
    // The Suite field may describe the suite. A suite is a single word.
    // e.g. "jessie" or "sid"
    auto suite = string(vf.File().Archive());
    // An area within the repository. May be prefixed by parts of the path
    // following the directory beneath dists.
    // e.g. "main" or "non-free"
    // NOTE: this may need the slash stripped, currently having a slash doesn't
    //    seem a problem though. we'll allow them until otherwise indicated
    auto component = string(vf.File().Component());

    // Origin is defined as 'a single line of free form text'.
    // Sanitize it!
    // All space characters, control characters and punctuation get replaced
    // with underscore.
    // In particular the punctuations ':', ';' and ',' may be used as list separators
    // so we must not have them appear in our package_ids as that would cause
    // breakage down the line.
    std::transform(origin.begin(), origin.end(), origin.begin(), ::tolower);
    origin = std::regex_replace(origin, std::regex("[[:space:][:cntrl:][:punct:]]+"), "_");

    string res = origin + "-" + suite + "-" + component;
    return res;
}

const char *toUtf8(const char *str)
{
    static __thread char *_str = NULL;
    if (str == NULL)
        return NULL;

    if (g_utf8_validate(str, -1, NULL) == true)
        return str;

    g_free(_str);
    _str = NULL;
    _str = g_locale_to_utf8(str, -1, NULL, NULL, NULL);
    return _str;
}

string changelogDateToIso8601(const string &date)
{
    if (date.empty()) {
        return {};
    }

    std::istringstream date_ss(date);
    date_ss.imbue(std::locale("C")); // Dates are always in English locale
    tm time = {};
    date_ss >> get_time(&time, "%a, %d %b %Y %H:%M:%S ");
    if (date_ss.fail()) {
        return {};
    }

    // Timezone is not parsed by get_time(), so it remains at the end of the stream
    string tz_str;
    date_ss >> tz_str;
    g_autoptr(GTimeZone) tz = g_time_zone_new_identifier(tz_str.c_str());
    if (!tz) {
        tz = g_time_zone_new_utc();
    }

    g_autoptr(GDateTime) dateTime = g_date_time_new(
        tz, time.tm_year + 1900, time.tm_mon + 1, time.tm_mday, time.tm_hour, time.tm_min, time.tm_sec);

    if (dateTime == NULL) {
        return {};
    }

    return string(g_date_time_format_iso8601(dateTime));
}
