// SPDX-License-Identifier: GPL-3.0-or-later
// SPDX-FileCopyrightText: 2026 A-La-Karte Contributors

#include "desktopimporter.h"

#include <KConfigGroup>
#include <KDesktopFile>
#include <QDir>
#include <QFile>
#include <QRegularExpression>
#include <QStandardPaths>

DesktopImporter::DesktopImporter(QObject *parent)
    : PlatformImporter(parent)
{
}

QString DesktopImporter::platformName() const
{
    return QStringLiteral("Desktop");
}

QString DesktopImporter::platformId() const
{
    return QStringLiteral("desktop");
}

bool DesktopImporter::isAvailable() const
{
    return true;
}

QStringList DesktopImporter::getDesktopFilePaths() const
{
    QStringList paths;

    // Standard XDG application directories
    QStringList appDirs = QStandardPaths::standardLocations(QStandardPaths::ApplicationsLocation);

    // Add common system locations
    appDirs << QStringLiteral("/usr/share/applications");
    appDirs << QStringLiteral("/usr/local/share/applications");
    appDirs << expandPath(QStringLiteral("~/.local/share/applications"));

    // Flatpak export directories
    appDirs << expandPath(QStringLiteral("~/.local/share/flatpak/exports/share/applications"));
    appDirs << QStringLiteral("/var/lib/flatpak/exports/share/applications");

    for (const QString &dir : appDirs) {
        QDir appDir(dir);
        if (appDir.exists()) {
            QStringList files = appDir.entryList({QStringLiteral("*.desktop")}, QDir::Files);
            for (const QString &file : files) {
                QString fullPath = appDir.absoluteFilePath(file);
                if (!paths.contains(fullPath)) {
                    paths << fullPath;
                }
            }
        }
    }

    return paths;
}

bool DesktopImporter::isGameDesktopFile(const QString &filePath) const
{
    KDesktopFile desktopFile(filePath);
    KConfigGroup desktop = desktopFile.desktopGroup();

    const QString type = desktop.readEntry(QStringLiteral("Type"));
    if (type != QStringLiteral("Application")) {
        return false;
    }

    // Check if hidden or not shown
    if (desktop.readEntry(QStringLiteral("Hidden"), false)) {
        return false;
    }
    if (desktop.readEntry(QStringLiteral("NoDisplay"), false)) {
        return false;
    }

    // Check categories for game-related entries
    const QStringList categories = desktop.readEntry(QStringLiteral("Categories")).split(QLatin1Char(';'), Qt::SkipEmptyParts);

    return hasGameCategory(categories);
}

Game *DesktopImporter::parseDesktopFile(const QString &filePath) const
{
    KDesktopFile desktopFile(filePath);
    KConfigGroup desktop = desktopFile.desktopGroup();

    const QString name = desktop.readEntry(QStringLiteral("Name"));
    QString exec = desktop.readEntry(QStringLiteral("Exec"));
    const QString icon = desktop.readEntry(QStringLiteral("Icon"));
    const QString comment = desktop.readEntry(QStringLiteral("Comment"));
    const QString genericName = desktop.readEntry(QStringLiteral("GenericName"));

    if (name.isEmpty() || exec.isEmpty()) {
        return nullptr;
    }

    // Clean up the exec command - remove field codes like %f, %u, %F, %U
    static QRegularExpression fieldCodeRegex(QStringLiteral("%[fFuUdDnNickvm]"));
    exec = exec.remove(fieldCodeRegex).trimmed();

    // Create unique ID from the desktop file name
    QFileInfo fileInfo(filePath);
    const QString desktopId = fileInfo.completeBaseName();
    QString gameId = QStringLiteral("desktop_") + desktopId;

    Game *game = new Game(gameId, name);
    game->setLaunchCommand(exec);
    game->setPlatform(platformName());
    game->setPlatformId(desktopId);

    if (!comment.isEmpty()) {
        game->setDescription(comment);
    } else if (!genericName.isEmpty()) {
        game->setDescription(genericName);
    }

    // Try to find icon
    if (!icon.isEmpty()) {
        // If it's an absolute path, use it directly
        if (QFile::exists(icon)) {
            game->setIconUrl(QUrl::fromLocalFile(icon));
        } else {
            // Try to find in standard icon locations
            QStringList iconPaths = {
                expandPath(QStringLiteral("~/.local/share/icons/hicolor/256x256/apps/") + icon + QStringLiteral(".png")),
                QStringLiteral("/usr/share/icons/hicolor/256x256/apps/") + icon + QStringLiteral(".png"),
                QStringLiteral("/usr/share/pixmaps/") + icon + QStringLiteral(".png"),
                expandPath(QStringLiteral("~/.local/share/icons/hicolor/128x128/apps/") + icon + QStringLiteral(".png")),
                QStringLiteral("/usr/share/icons/hicolor/128x128/apps/") + icon + QStringLiteral(".png"),
            };

            for (const QString &iconPath : iconPaths) {
                if (QFile::exists(iconPath)) {
                    const QUrl url = QUrl::fromLocalFile(iconPath);
                    game->setIconUrl(url);
                    if (!game->coverUrl().isValid() || game->coverUrl().isEmpty()) {
                        game->setCoverUrl(url);
                    }
                    break;
                }
            }
        }
    }

    return game;
}

QList<Game *> DesktopImporter::importGames()
{
    QList<Game *> games;

    QStringList desktopFiles = getDesktopFilePaths();
    int total = desktopFiles.count();
    int current = 0;

    for (const QString &filePath : desktopFiles) {
        current++;
        Q_EMIT importProgress(current, total);

        if (!isGameDesktopFile(filePath)) {
            continue;
        }

        Game *game = parseDesktopFile(filePath);
        if (game) {
            games.append(game);
        }
    }

    return games;
}