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

#include "steamgriddb.h"
#include "app.h"
#include "game.h"

#include <KConfigGroup>
#include <KSharedConfig>
#include <QDir>
#include <QJsonArray>
#include <QJsonDocument>
#include <QJsonObject>
#include <QNetworkReply>
#include <QSaveFile>
#include <QStandardPaths>
#include <QUrlQuery>

static const QString STEAMGRIDDB_API_BASE = QStringLiteral("https://www.steamgriddb.com/api/v2");

SteamGridDB::SteamGridDB(QObject *parent)
    : QObject(parent)
    , m_networkManager(new QNetworkAccessManager(this))
{
    loadSettings();
}

QString SteamGridDB::apiKey() const
{
    return m_apiKey;
}

void SteamGridDB::setApiKey(const QString &key)
{
    if (m_apiKey != key) {
        m_apiKey = key;
        saveSettings();
        Q_EMIT apiKeyChanged();
    }
}

bool SteamGridDB::enabled() const
{
    return m_enabled;
}

void SteamGridDB::setEnabled(bool enabled)
{
    if (m_enabled != enabled) {
        m_enabled = enabled;
        saveSettings();
        Q_EMIT enabledChanged();
    }
}

bool SteamGridDB::preferSteamGridDB() const
{
    return m_preferSteamGridDB;
}

void SteamGridDB::setPreferSteamGridDB(bool prefer)
{
    if (m_preferSteamGridDB != prefer) {
        m_preferSteamGridDB = prefer;
        saveSettings();
        Q_EMIT preferSteamGridDBChanged();
    }
}

bool SteamGridDB::busy() const
{
    return m_busy;
}

void SteamGridDB::fetchCover(Game *game)
{
    if (!game || m_apiKey.isEmpty() || !m_enabled) {
        return;
    }

    // Skip if game already has a cover and we don't prefer SteamGridDB
    if (game->coverUrl().isValid() && !m_preferSteamGridDB) {
        return;
    }

    m_pendingGames.append(game);

    if (!m_busy) {
        m_totalGames = m_pendingGames.count();
        m_processedGames = 0;
        processNextGame();
    }
}

void SteamGridDB::fetchAllCovers()
{
    if (m_apiKey.isEmpty() || !m_enabled) {
        return;
    }

    GameModel *gameModel = App::instance()->gameModel();
    for (int i = 0; i < gameModel->rowCount(); ++i) {
        Game *game = gameModel->gameAt(i);
        if (game && (!game->coverUrl().isValid() || m_preferSteamGridDB)) {
            m_pendingGames.append(game);
        }
    }

    if (!m_pendingGames.isEmpty() && !m_busy) {
        m_totalGames = m_pendingGames.count();
        m_processedGames = 0;
        processNextGame();
    }
}

void SteamGridDB::processNextGame()
{
    if (m_pendingGames.isEmpty()) {
        m_busy = false;
        m_currentGame = nullptr;
        Q_EMIT busyChanged();
        return;
    }

    m_busy = true;
    Q_EMIT busyChanged();

    m_currentGame = m_pendingGames.takeFirst();
    searchGame(m_currentGame);
}

void SteamGridDB::searchGame(Game *game)
{
    QString encodedName = QString::fromUtf8(QUrl::toPercentEncoding(game->name()));
    QUrl url(STEAMGRIDDB_API_BASE + QStringLiteral("/search/autocomplete/") + encodedName);

    QNetworkRequest request(url);
    request.setRawHeader("Authorization", QStringLiteral("Bearer %1").arg(m_apiKey).toUtf8());

    QNetworkReply *reply = m_networkManager->get(request);
    reply->setProperty("game", QVariant::fromValue(game));
    connect(reply, &QNetworkReply::finished, this, &SteamGridDB::onSearchFinished);
}

void SteamGridDB::onSearchFinished()
{
    QNetworkReply *reply = qobject_cast<QNetworkReply *>(sender());
    if (!reply) {
        processNextGame();
        return;
    }

    reply->deleteLater();

    Game *game = reply->property("game").value<Game *>();
    if (!game) {
        processNextGame();
        return;
    }

    if (reply->error() != QNetworkReply::NoError) {
        Q_EMIT fetchError(game, reply->errorString());
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    QJsonDocument doc = QJsonDocument::fromJson(reply->readAll());
    QJsonObject root = doc.object();

    if (!root[QStringLiteral("success")].toBool()) {
        Q_EMIT fetchError(game, QStringLiteral("Search failed"));
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    QJsonArray data = root[QStringLiteral("data")].toArray();
    if (data.isEmpty()) {
        Q_EMIT fetchError(game, QStringLiteral("No results found"));
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    // Use the first result
    QJsonObject firstResult = data.first().toObject();
    int gameId = firstResult[QStringLiteral("id")].toInt();

    fetchGrids(game, gameId);
}

void SteamGridDB::fetchGrids(Game *game, int gameId)
{
    // Request vertical grids (600x900) for game covers
    QUrl url(STEAMGRIDDB_API_BASE + QStringLiteral("/grids/game/%1").arg(gameId));
    QUrlQuery query;
    query.addQueryItem(QStringLiteral("dimensions"), QStringLiteral("600x900"));
    query.addQueryItem(QStringLiteral("types"), QStringLiteral("static"));
    url.setQuery(query);

    QNetworkRequest request(url);
    request.setRawHeader("Authorization", QStringLiteral("Bearer %1").arg(m_apiKey).toUtf8());

    QNetworkReply *reply = m_networkManager->get(request);
    reply->setProperty("game", QVariant::fromValue(game));
    connect(reply, &QNetworkReply::finished, this, &SteamGridDB::onGridsFinished);
}

void SteamGridDB::onGridsFinished()
{
    QNetworkReply *reply = qobject_cast<QNetworkReply *>(sender());
    if (!reply) {
        processNextGame();
        return;
    }

    reply->deleteLater();

    Game *game = reply->property("game").value<Game *>();
    if (!game) {
        processNextGame();
        return;
    }

    if (reply->error() != QNetworkReply::NoError) {
        Q_EMIT fetchError(game, reply->errorString());
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    QJsonDocument doc = QJsonDocument::fromJson(reply->readAll());
    QJsonObject root = doc.object();

    if (!root[QStringLiteral("success")].toBool()) {
        Q_EMIT fetchError(game, QStringLiteral("Failed to fetch grids"));
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    QJsonArray data = root[QStringLiteral("data")].toArray();
    if (data.isEmpty()) {
        Q_EMIT fetchError(game, QStringLiteral("No covers available"));
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    // Use the first (highest rated) result
    QJsonObject firstGrid = data.first().toObject();
    QString imageUrl = firstGrid[QStringLiteral("url")].toString();

    downloadImage(game, QUrl(imageUrl));
}

void SteamGridDB::downloadImage(Game *game, const QUrl &imageUrl)
{
    QNetworkRequest request(imageUrl);
    QNetworkReply *reply = m_networkManager->get(request);
    reply->setProperty("game", QVariant::fromValue(game));
    connect(reply, &QNetworkReply::finished, this, &SteamGridDB::onImageDownloaded);
}

void SteamGridDB::onImageDownloaded()
{
    QNetworkReply *reply = qobject_cast<QNetworkReply *>(sender());
    if (!reply) {
        processNextGame();
        return;
    }

    reply->deleteLater();

    Game *game = reply->property("game").value<Game *>();
    if (!game) {
        processNextGame();
        return;
    }

    if (reply->error() != QNetworkReply::NoError) {
        Q_EMIT fetchError(game, reply->errorString());
        m_processedGames++;
        Q_EMIT fetchProgress(m_processedGames, m_totalGames);
        processNextGame();
        return;
    }

    // Save image to covers directory
    QString coversPath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation) + QStringLiteral("/covers");
    QDir dir(coversPath);
    if (!dir.exists()) {
        if (!dir.mkpath(coversPath)) {
            Q_EMIT fetchError(game, QStringLiteral("Failed to create covers directory"));
            m_processedGames++;
            Q_EMIT fetchProgress(m_processedGames, m_totalGames);
            processNextGame();
            return;
        }
    }

    QString fileName = game->id() + QStringLiteral(".jpg");
    QString filePath = coversPath + QStringLiteral("/") + fileName;

    const QByteArray payload = reply->readAll();
    QSaveFile file(filePath);
    if (file.open(QIODevice::WriteOnly | QIODevice::Truncate)) {
        if (file.write(payload) != payload.size() || !file.commit()) {
            Q_EMIT fetchError(game, QStringLiteral("Failed to save cover image"));
            m_processedGames++;
            Q_EMIT fetchProgress(m_processedGames, m_totalGames);
            processNextGame();
            return;
        }

        QUrl localUrl = QUrl::fromLocalFile(filePath);
        game->setCoverUrl(localUrl);
        App::instance()->saveLibrary();

        Q_EMIT coverFetched(game, localUrl);
    } else {
        Q_EMIT fetchError(game, QStringLiteral("Failed to save cover image"));
    }

    m_processedGames++;
    Q_EMIT fetchProgress(m_processedGames, m_totalGames);
    processNextGame();
}

void SteamGridDB::saveSettings()
{
    const auto config = KSharedConfig::openConfig(QStringLiteral("alakarterc"));
    KConfigGroup group(config, QStringLiteral("SteamGridDB"));
    group.writeEntry(QStringLiteral("apiKey"), m_apiKey);
    group.writeEntry(QStringLiteral("enabled"), m_enabled);
    group.writeEntry(QStringLiteral("preferSteamGridDB"), m_preferSteamGridDB);
    config->sync();
}

void SteamGridDB::loadSettings()
{
    const auto config = KSharedConfig::openConfig(QStringLiteral("alakarterc"));
    const KConfigGroup group(config, QStringLiteral("SteamGridDB"));
    m_apiKey = group.readEntry(QStringLiteral("apiKey"), QString());
    m_enabled = group.readEntry(QStringLiteral("enabled"), false);
    m_preferSteamGridDB = group.readEntry(QStringLiteral("preferSteamGridDB"), false);
}