Merge branch 'develop' of https://github.com/PrismLauncher/PrismLauncher into import

15 files changed, 392 insertions, 65 deletions

diff --git a/flake.lock b/flake.lock
index 91a67f08..370250c4 100644
--- a/flake.lock
+++ b/flake.lock
@@ -21,11 +21,11 @@
         "nixpkgs-lib": "nixpkgs-lib"
       },
       "locked": {
-        "lastModified": 1688254665,
-        "narHash": "sha256-8FHEgBrr7gYNiS/NzCxIO3m4hvtLRW9YY1nYo1ivm3o=",
+        "lastModified": 1688466019,
+        "narHash": "sha256-VeM2akYrBYMsb4W/MmBo1zmaMfgbL4cH3Pu8PGyIwJ0=",
         "owner": "hercules-ci",
         "repo": "flake-parts",
-        "rev": "267149c58a14d15f7f81b4d737308421de9d7152",
+        "rev": "8e8d955c22df93dbe24f19ea04f47a74adbdc5ec",
         "type": "github"
       },
       "original": {
@@ -91,11 +91,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1688221086,
-        "narHash": "sha256-cdW6qUL71cNWhHCpMPOJjlw0wzSRP0pVlRn2vqX/VVg=",
+        "lastModified": 1689413807,
+        "narHash": "sha256-exuzOvOhGAEKWQKwDuZAL4N8a1I837hH5eocaTcIbLc=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "cd99c2b3c9f160cd004318e0697f90bbd5960825",
+        "rev": "46ed466081b9cad1125b11f11a2af5cc40b942c7",
         "type": "github"
       },
       "original": {
@@ -138,11 +138,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1688386108,
-        "narHash": "sha256-Vffto9QaVonzYAcPlAzd0soqWYpPpKk60dfNLSIXcFA=",
+        "lastModified": 1689328505,
+        "narHash": "sha256-9B3+OeUn1a/CvzE3GW6nWNwS5J7PDHTyHGlpL3wV5oA=",
         "owner": "cachix",
         "repo": "pre-commit-hooks.nix",
-        "rev": "42587d3414d1747999a5f71e92a83cf6547b62da",
+        "rev": "5e28316db471d1ac234beb70031b635437421dd6",
         "type": "github"
       },
       "original": {
diff --git a/launcher/Application.cpp b/launcher/Application.cpp
index d6c135de..aeea90f1 100644
--- a/launcher/Application.cpp
+++ b/launcher/Application.cpp
@@ -1186,7 +1186,17 @@ QIcon Application::getThemedIcon(const QString& name)
     return QIcon::fromTheme(name);
 }
 
-bool Application::openJsonEditor(const QString &filename)
+QList<CatPack*> Application::getValidCatPacks()
+{
+    return m_themeManager->getValidCatPacks();
+}
+
+QString Application::getCatPack(QString catName)
+{
+    return m_themeManager->getCatPack(catName);
+}
+
+bool Application::openJsonEditor(const QString& filename)
 {
     const QString file = QDir::current().absoluteFilePath(filename);
     if (m_settings->get("JsonEditor").toString().isEmpty())
diff --git a/launcher/Application.h b/launcher/Application.h
index 527c536b..c0a980b2 100644
--- a/launcher/Application.h
+++ b/launcher/Application.h
@@ -48,6 +48,7 @@
 #include <BaseInstance.h>
 
 #include "minecraft/launch/MinecraftServerTarget.h"
+#include "ui/themes/CatPack.h"
 
 class LaunchController;
 class LocalPeer;
@@ -126,9 +127,11 @@ public:
 
     void setApplicationTheme(const QString& name);
 
-    shared_qobject_ptr<ExternalUpdater> updater() {
-        return m_updater;
-    }
+    QList<CatPack*> getValidCatPacks();
+
+    QString getCatPack(QString catName = "");
+
+    shared_qobject_ptr<ExternalUpdater> updater() { return m_updater; }
 
     void triggerUpdateCheck();
 
diff --git a/launcher/CMakeLists.txt b/launcher/CMakeLists.txt
index 05312499..302d39e6 100644
--- a/launcher/CMakeLists.txt
+++ b/launcher/CMakeLists.txt
@@ -766,6 +766,8 @@ SET(LAUNCHER_SOURCES
     ui/themes/SystemTheme.h
     ui/themes/ThemeManager.cpp
     ui/themes/ThemeManager.h
+    ui/themes/CatPack.cpp
+    ui/themes/CatPack.h
 
     # Processes
     LaunchController.h
diff --git a/launcher/minecraft/auth/AuthSession.cpp b/launcher/minecraft/auth/AuthSession.cpp
index 6bea74a3..2c06beaa 100644
--- a/launcher/minecraft/auth/AuthSession.cpp
+++ b/launcher/minecraft/auth/AuthSession.cpp
@@ -26,6 +26,7 @@ bool AuthSession::MakeOffline(QString offline_playername)
         return false;
     }
     session = "-";
+    access_token = "0";
     player_name = offline_playername;
     status = PlayableOffline;
     return true;
diff --git a/launcher/minecraft/auth/MinecraftAccount.cpp b/launcher/minecraft/auth/MinecraftAccount.cpp
index 3b050ac0..d7b061e5 100644
--- a/launcher/minecraft/auth/MinecraftAccount.cpp
+++ b/launcher/minecraft/auth/MinecraftAccount.cpp
@@ -37,6 +37,7 @@
 
 #include "MinecraftAccount.h"
 
+#include <QCryptographicHash>
 #include <QUuid>
 #include <QJsonObject>
 #include <QJsonArray>
@@ -100,7 +101,7 @@ MinecraftAccountPtr MinecraftAccount::createOffline(const QString &username)
     account->data.yggdrasilToken.extra["clientToken"] = QUuid::createUuid().toString().remove(QRegularExpression("[{}-]"));
     account->data.minecraftEntitlement.ownsMinecraft = true;
     account->data.minecraftEntitlement.canPlayMinecraft = true;
-    account->data.minecraftProfile.id = QUuid::createUuid().toString().remove(QRegularExpression("[{}-]"));
+    account->data.minecraftProfile.id = uuidFromUsername(username).toString().remove(QRegularExpression("[{}-]"));
     account->data.minecraftProfile.name = username;
     account->data.minecraftProfile.validity = Katabasis::Validity::Certain;
     return account;
@@ -334,3 +335,32 @@ void MinecraftAccount::incrementUses()
         qWarning() << "Profile" << data.profileId() << "is now in use.";
     }
 }
+
+QUuid MinecraftAccount::uuidFromUsername(QString username) {
+    auto input = QString("OfflinePlayer:%1").arg(username).toUtf8();
+
+    // basically a reimplementation of Java's UUID#nameUUIDFromBytes
+    QByteArray digest = QCryptographicHash::hash(input, QCryptographicHash::Md5);
+
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+    auto bOr = [](QByteArray& array, int index, char value) {
+        array[index] = array.at(index) | value;
+    };
+    auto bAnd = [](QByteArray& array, int index, char value) {
+        array[index] = array.at(index) & value;
+    };
+#else
+    auto bOr = [](QByteArray& array, qsizetype index, char value) {
+        array[index] |= value;
+    };
+    auto bAnd = [](QByteArray& array, qsizetype index, char value) {
+        array[index] &= value;
+    };
+#endif
+    bAnd(digest, 6, (char) 0x0f); // clear version
+    bOr(digest, 6, (char) 0x30); // set to version 3
+    bAnd(digest, 8, (char) 0x3f); // clear variant
+    bOr(digest, 8, (char) 0x80); // set to IETF variant
+
+    return QUuid::fromRfc4122(digest);
+}
diff --git a/launcher/minecraft/auth/MinecraftAccount.h b/launcher/minecraft/auth/MinecraftAccount.h
index 0dcaeb53..67623a5a 100644
--- a/launcher/minecraft/auth/MinecraftAccount.h
+++ b/launcher/minecraft/auth/MinecraftAccount.h
@@ -98,6 +98,8 @@ public: /* construction */
     static MinecraftAccountPtr loadFromJsonV2(const QJsonObject &json);
     static MinecraftAccountPtr loadFromJsonV3(const QJsonObject &json);
 
+    static QUuid uuidFromUsername(QString username);
+
     //! Saves a MinecraftAccount to a JSON object and returns it.
     QJsonObject saveToJson() const;
 
diff --git a/launcher/ui/instanceview/InstanceView.cpp b/launcher/ui/instanceview/InstanceView.cpp
index 1911dd59..05f0004d 100644
--- a/launcher/ui/instanceview/InstanceView.cpp
+++ b/launcher/ui/instanceview/InstanceView.cpp
@@ -48,7 +48,6 @@
 #include <QAccessible>
 
 #include "VisualGroup.h"
-#include "ui/themes/ThemeManager.h"
 #include <QDebug>
 
 #include <Application.h>
@@ -504,7 +503,7 @@ void InstanceView::setPaintCat(bool visible)
 {
     m_catVisible = visible;
     if (visible)
-        m_catPixmap.load(QString(":/backgrounds/%1").arg(ThemeManager::getCatImage()));
+        m_catPixmap.load(APPLICATION->getCatPack());
     else
         m_catPixmap = QPixmap();
 }
diff --git a/launcher/ui/setupwizard/ThemeWizardPage.cpp b/launcher/ui/setupwizard/ThemeWizardPage.cpp
index c3e0a524..1c336921 100644
--- a/launcher/ui/setupwizard/ThemeWizardPage.cpp
+++ b/launcher/ui/setupwizard/ThemeWizardPage.cpp
@@ -61,7 +61,7 @@ void ThemeWizardPage::updateIcons()
 void ThemeWizardPage::updateCat()
 {
     qDebug() << "Setting Cat";
-    ui->catImagePreviewButton->setIcon(QIcon(QString(R"(:/backgrounds/%1)").arg(ThemeManager::getCatImage())));
+    ui->catImagePreviewButton->setIcon(QIcon(QString(R"(%1)").arg(APPLICATION->getCatPack())));
 }
 
 void ThemeWizardPage::retranslate()
diff --git a/launcher/ui/themes/CatPack.cpp b/launcher/ui/themes/CatPack.cpp
new file mode 100644
index 00000000..f0d8ddd5
--- /dev/null
+++ b/launcher/ui/themes/CatPack.cpp
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  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, version 3.
+ *
+ *  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.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ *      Copyright 2013-2021 MultiMC Contributors
+ *
+ *      Licensed under the Apache License, Version 2.0 (the "License");
+ *      you may not use this file except in compliance with the License.
+ *      You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *      Unless required by applicable law or agreed to in writing, software
+ *      distributed under the License is distributed on an "AS IS" BASIS,
+ *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *      See the License for the specific language governing permissions and
+ *      limitations under the License.
+ */
+
+#include "ui/themes/CatPack.h"
+#include <QDate>
+#include <QDir>
+#include <QFileInfo>
+#include "FileSystem.h"
+#include "Json.h"
+
+QString BasicCatPack::path()
+{
+    const auto now = QDate::currentDate();
+    const auto birthday = QDate(now.year(), 11, 30);
+    const auto xmas = QDate(now.year(), 12, 25);
+    const auto halloween = QDate(now.year(), 10, 31);
+
+    QString cat = QString(":/backgrounds/%1").arg(m_id);
+    if (std::abs(now.daysTo(xmas)) <= 4) {
+        cat += "-xmas";
+    } else if (std::abs(now.daysTo(halloween)) <= 4) {
+        cat += "-spooky";
+    } else if (std::abs(now.daysTo(birthday)) <= 12) {
+        cat += "-bday";
+    }
+    return cat;
+}
+
+JsonCatPack::PartialDate partialDate(QJsonObject date)
+{
+    auto month = Json::ensureInteger(date, "month", 1);
+    if (month > 12)
+        month = 12;
+    else if (month <= 0)
+        month = 1;
+    auto day = Json::ensureInteger(date, "day", 1);
+    if (day > 31)
+        day = 31;
+    else if (day <= 0)
+        day = 1;
+    return { month, day };
+};
+
+JsonCatPack::JsonCatPack(QFileInfo& manifestInfo) : BasicCatPack(manifestInfo.dir().dirName())
+{
+    QString path = manifestInfo.path();
+    auto doc = Json::requireDocument(manifestInfo.absoluteFilePath(), "CatPack JSON file");
+    const auto root = doc.object();
+    m_name = Json::requireString(root, "name", "Catpack name");
+    m_defaultPath = FS::PathCombine(path, Json::requireString(root, "default", "Default Cat"));
+    auto variants = Json::ensureArray(root, "variants", QJsonArray(), "Catpack Variants");
+    for (auto v : variants) {
+        auto variant = Json::ensureObject(v, QJsonObject(), "Cat variant");
+        m_variants << Variant{ FS::PathCombine(path, Json::requireString(variant, "path", "Variant path")),
+                               partialDate(Json::requireObject(variant, "startTime", "Variant startTime")),
+                               partialDate(Json::requireObject(variant, "endTime", "Variant endTime")) };
+    }
+}
+
+QDate ensureDay(int year, int month, int day)
+{
+    QDate date(year, month, 1);
+    if (day > date.daysInMonth())
+        day = date.daysInMonth();
+    return QDate(year, month, day);
+}
+
+QString JsonCatPack::path()
+{
+    const QDate now = QDate::currentDate();
+    for (auto var : m_variants) {
+        QDate startDate = ensureDay(now.year(), var.startTime.month, var.startTime.day);
+        QDate endDate = ensureDay(now.year(), var.endTime.month, var.endTime.day);
+        if (startDate > endDate) {  // it's spans over multiple years
+            if (endDate <= now)     // end date is in the past so jump one year into the future for endDate
+                endDate = endDate.addYears(1);
+            else  // end date is in the future so jump one year into the past for startDate
+                startDate = startDate.addYears(-1);
+        }
+
+        if (startDate >= now && now >= endDate)
+            return var.path;
+    }
+    return m_defaultPath;
+}
diff --git a/launcher/ui/themes/CatPack.h b/launcher/ui/themes/CatPack.h
new file mode 100644
index 00000000..b03a19f0
--- /dev/null
+++ b/launcher/ui/themes/CatPack.h
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  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, version 3.
+ *
+ *  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.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ *      Copyright 2013-2021 MultiMC Contributors
+ *
+ *      Licensed under the Apache License, Version 2.0 (the "License");
+ *      you may not use this file except in compliance with the License.
+ *      You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *      Unless required by applicable law or agreed to in writing, software
+ *      distributed under the License is distributed on an "AS IS" BASIS,
+ *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *      See the License for the specific language governing permissions and
+ *      limitations under the License.
+ */
+
+#pragma once
+
+#include <QDate>
+#include <QFileInfo>
+#include <QList>
+#include <QString>
+
+class CatPack {
+   public:
+    virtual ~CatPack() {}
+    virtual QString id() = 0;
+    virtual QString name() = 0;
+    virtual QString path() = 0;
+};
+
+class BasicCatPack : public CatPack {
+   public:
+    BasicCatPack(QString id, QString name) : m_id(id), m_name(name) {}
+    BasicCatPack(QString id) : BasicCatPack(id, id) {}
+    virtual QString id() { return m_id; };
+    virtual QString name() { return m_name; };
+    virtual QString path();
+
+   protected:
+    QString m_id;
+    QString m_name;
+};
+
+class FileCatPack : public BasicCatPack {
+   public:
+    FileCatPack(QString id, QFileInfo& fileInfo) : BasicCatPack(id), m_path(fileInfo.absoluteFilePath()) {}
+    FileCatPack(QFileInfo& fileInfo) : FileCatPack(fileInfo.baseName(), fileInfo) {}
+    virtual QString path() { return m_path; }
+
+   private:
+    QString m_path;
+};
+
+class JsonCatPack : public BasicCatPack {
+   public:
+    struct PartialDate {
+        int month;
+        int day;
+    };
+    struct Variant {
+        QString path;
+        PartialDate startTime;
+        PartialDate endTime;
+    };
+    JsonCatPack(QFileInfo& manifestInfo);
+    virtual QString path();
+
+   private:
+    QString m_defaultPath;
+    QList<Variant> m_variants;
+};
diff --git a/launcher/ui/themes/ThemeManager.cpp b/launcher/ui/themes/ThemeManager.cpp
index b50c6157..321f7db4 100644
--- a/launcher/ui/themes/ThemeManager.cpp
+++ b/launcher/ui/themes/ThemeManager.cpp
@@ -21,7 +21,10 @@
 #include <QDir>
 #include <QDirIterator>
 #include <QIcon>
+#include <QImageReader>
+#include "Exception.h"
 #include "ui/themes/BrightTheme.h"
+#include "ui/themes/CatPack.h"
 #include "ui/themes/CustomTheme.h"
 #include "ui/themes/DarkTheme.h"
 #include "ui/themes/SystemTheme.h"
@@ -32,6 +35,7 @@ ThemeManager::ThemeManager(MainWindow* mainWindow)
 {
     m_mainWindow = mainWindow;
     initializeThemes();
+    initializeCatPacks();
 }
 
 /// @brief Adds the Theme to the list of themes
@@ -40,7 +44,10 @@ ThemeManager::ThemeManager(MainWindow* mainWindow)
 QString ThemeManager::addTheme(std::unique_ptr<ITheme> theme)
 {
     QString id = theme->id();
-    m_themes.emplace(id, std::move(theme));
+    if (m_themes.find(id) == m_themes.end())
+        m_themes.emplace(id, std::move(theme));
+    else
+        themeWarningLog() << "Theme(" << id << ") not added to prevent id duplication";
     return id;
 }
 
@@ -77,7 +84,7 @@ void ThemeManager::initializeThemes()
         QString themeFolder = QDir("./themes/").absoluteFilePath("");
         themeDebugLog() << "Theme Folder Path: " << themeFolder;
 
-        QDirIterator directoryIterator(themeFolder, QDir::Dirs | QDir::NoDotAndDotDot, QDirIterator::Subdirectories);
+        QDirIterator directoryIterator(themeFolder, QDir::Dirs | QDir::NoDotAndDotDot);
         while (directoryIterator.hasNext()) {
             QDir dir(directoryIterator.next());
             QFileInfo themeJson(dir.absoluteFilePath("theme.json"));
@@ -111,6 +118,16 @@ QList<ITheme*> ThemeManager::getValidApplicationThemes()
     return ret;
 }
 
+QList<CatPack*> ThemeManager::getValidCatPacks()
+{
+    QList<CatPack*> ret;
+    ret.reserve(m_catPacks.size());
+    for (auto&& [id, theme] : m_catPacks) {
+        ret.append(theme.get());
+    }
+    return ret;
+}
+
 void ThemeManager::setIconTheme(const QString& name)
 {
     QIcon::setThemeName(name);
@@ -137,19 +154,74 @@ void ThemeManager::setApplicationTheme(const QString& name, bool initial)
     }
 }
 
-QString ThemeManager::getCatImage(QString catName)
+QString ThemeManager::getCatPack(QString catName)
+{
+    auto catIter = m_catPacks.find(!catName.isEmpty() ? catName : APPLICATION->settings()->get("BackgroundCat").toString());
+    if (catIter != m_catPacks.end()) {
+        auto& catPack = catIter->second;
+        themeDebugLog() << "applying catpack" << catPack->id();
+        return catPack->path();
+    } else {
+        themeWarningLog() << "Tried to get invalid catPack:" << catName;
+    }
+
+    return m_catPacks.begin()->second->path();
+}
+
+QString ThemeManager::addCatPack(std::unique_ptr<CatPack> catPack)
 {
-    QDateTime now = QDateTime::currentDateTime();
-    QDateTime birthday(QDate(now.date().year(), 11, 30), QTime(0, 0));
-    QDateTime xmas(QDate(now.date().year(), 12, 25), QTime(0, 0));
-    QDateTime halloween(QDate(now.date().year(), 10, 31), QTime(0, 0));
-    QString cat = !catName.isEmpty() ? catName : APPLICATION->settings()->get("BackgroundCat").toString();
-    if (std::abs(now.daysTo(xmas)) <= 4) {
-        cat += "-xmas";
-    } else if (std::abs(now.daysTo(halloween)) <= 4) {
-        cat += "-spooky";
-    } else if (std::abs(now.daysTo(birthday)) <= 12) {
-        cat += "-bday";
+    QString id = catPack->id();
+    if (m_catPacks.find(id) == m_catPacks.end())
+        m_catPacks.emplace(id, std::move(catPack));
+    else
+        themeWarningLog() << "CatPack(" << id << ") not added to prevent id duplication";
+    return id;
+}
+
+void ThemeManager::initializeCatPacks()
+{
+    QList<std::pair<QString, QString>> defaultCats{ { "kitteh", QObject::tr("Background Cat (from MultiMC)") },
+                                                    { "rory", QObject::tr("Rory ID 11 (drawn by Ashtaka)") },
+                                                    { "rory-flat", QObject::tr("Rory ID 11 (flat edition, drawn by Ashtaka)") },
+                                                    { "teawie", QObject::tr("Teawie (drawn by SympathyTea)") } };
+    for (auto [id, name] : defaultCats) {
+        addCatPack(std::unique_ptr<CatPack>(new BasicCatPack(id, name)));
+    }
+    QDir catpacksDir("catpacks");
+    QString catpacksFolder = catpacksDir.absoluteFilePath("");
+    themeDebugLog() << "CatPacks Folder Path:" << catpacksFolder;
+
+    QStringList supportedImageFormats;
+    for (auto format : QImageReader::supportedImageFormats()) {
+        supportedImageFormats.append("*." + format);
+    }
+    auto loadFiles = [this, supportedImageFormats](QDir dir) {
+        // Load image files directly
+        QDirIterator ImageFileIterator(dir.absoluteFilePath(""), supportedImageFormats, QDir::Files);
+        while (ImageFileIterator.hasNext()) {
+            QFile customCatFile(ImageFileIterator.next());
+            QFileInfo customCatFileInfo(customCatFile);
+            themeDebugLog() << "Loading CatPack from:" << customCatFileInfo.absoluteFilePath();
+            addCatPack(std::unique_ptr<CatPack>(new FileCatPack(customCatFileInfo)));
+        }
+    };
+
+    loadFiles(catpacksDir);
+
+    QDirIterator directoryIterator(catpacksFolder, QDir::Dirs | QDir::NoDotAndDotDot);
+    while (directoryIterator.hasNext()) {
+        QDir dir(directoryIterator.next());
+        QFileInfo manifest(dir.absoluteFilePath("catpack.json"));
+        if (manifest.isFile()) {
+            try {
+                // Load background manifest
+                themeDebugLog() << "Loading background manifest from:" << manifest.absoluteFilePath();
+                addCatPack(std::unique_ptr<CatPack>(new JsonCatPack(manifest)));
+            } catch (const Exception& e) {
+                themeWarningLog() << "Couldn't load catpack json:" << e.cause();
+            }
+        } else {
+            loadFiles(dir);
+        }
     }
-    return cat;
 }
diff --git a/launcher/ui/themes/ThemeManager.h b/launcher/ui/themes/ThemeManager.h
index d2a6fb70..1ce8c6f4 100644
--- a/launcher/ui/themes/ThemeManager.h
+++ b/launcher/ui/themes/ThemeManager.h
@@ -20,6 +20,7 @@
 #include <QString>
 
 #include "ui/MainWindow.h"
+#include "ui/themes/CatPack.h"
 #include "ui/themes/ITheme.h"
 
 inline auto themeDebugLog()
@@ -40,18 +41,20 @@ class ThemeManager {
     void applyCurrentlySelectedTheme(bool initial = false);
     void setApplicationTheme(const QString& name, bool initial = false);
 
-    /// <summary>
-    /// Returns the cat based on selected cat and with events (Birthday, XMas, etc.)
-    /// </summary>
-    /// <param name="catName">Optional, if you need a specific cat.</param>
-    /// <returns></returns>
-    static QString getCatImage(QString catName = "");
+    /// @brief Returns the background based on selected and with events (Birthday, XMas, etc.)
+    /// @param catName Optional, if you need a specific background.
+    /// @return
+    QString getCatPack(QString catName = "");
+    QList<CatPack*> getValidCatPacks();
 
    private:
     std::map<QString, std::unique_ptr<ITheme>> m_themes;
+    std::map<QString, std::unique_ptr<CatPack>> m_catPacks;
     MainWindow* m_mainWindow;
 
     void initializeThemes();
+    void initializeCatPacks();
     QString addTheme(std::unique_ptr<ITheme> theme);
     ITheme* getTheme(QString themeId);
+    QString addCatPack(std::unique_ptr<CatPack> catPack);
 };
diff --git a/launcher/ui/widgets/ThemeCustomizationWidget.cpp b/launcher/ui/widgets/ThemeCustomizationWidget.cpp
index 3bfcd821..291f8ed9 100644
--- a/launcher/ui/widgets/ThemeCustomizationWidget.cpp
+++ b/launcher/ui/widgets/ThemeCustomizationWidget.cpp
@@ -95,9 +95,14 @@ void ThemeCustomizationWidget::applyWidgetTheme(int index) {
     emit currentWidgetThemeChanged(index);
 }
 
-void ThemeCustomizationWidget::applyCatTheme(int index) {
+void ThemeCustomizationWidget::applyCatTheme(int index)
+{
     auto settings = APPLICATION->settings();
-    settings->set("BackgroundCat", m_catOptions[index].first);
+    auto originalCat = settings->get("BackgroundCat").toString();
+    auto newCat = ui->backgroundCatComboBox->currentData().toString();
+    if (originalCat != newCat) {
+        settings->set("BackgroundCat", newCat);
+    }
 
     emit currentCatChanged(index);
 }
@@ -135,10 +140,10 @@ void ThemeCustomizationWidget::loadSettings()
     }
 
     auto cat = settings->get("BackgroundCat").toString();
-    for (auto& catFromList : m_catOptions) {
-        QIcon catIcon = QIcon(QString(":/backgrounds/%1").arg(ThemeManager::getCatImage(catFromList.first)));
-        ui->backgroundCatComboBox->addItem(catIcon, catFromList.second);
-        if (cat == catFromList.first) {
+    for (auto& catFromList : APPLICATION->getValidCatPacks()) {
+        QIcon catIcon = QIcon(QString("%1").arg(catFromList->path()));
+        ui->backgroundCatComboBox->addItem(catIcon, catFromList->name(), catFromList->id());
+        if (cat == catFromList->id()) {
             ui->backgroundCatComboBox->setCurrentIndex(ui->backgroundCatComboBox->count() - 1);
         }
     }
diff --git a/launcher/ui/widgets/ThemeCustomizationWidget.h b/launcher/ui/widgets/ThemeCustomizationWidget.h
index 6c33c3c5..af47c788 100644
--- a/launcher/ui/widgets/ThemeCustomizationWidget.h
+++ b/launcher/ui/widgets/ThemeCustomizationWidget.h
@@ -53,25 +53,17 @@ class ThemeCustomizationWidget : public QWidget {
    private:
     Ui::ThemeCustomizationWidget* ui;
 
-    //TODO finish implementing
-    QList<std::pair<QString, QString>> m_iconThemeOptions{ 
-        { "pe_colored",     QObject::tr("Simple (Colored Icons)") }, 
-        { "pe_light",       QObject::tr("Simple (Light Icons)") },     
-        { "pe_dark",        QObject::tr("Simple (Dark Icons)") },
-        { "pe_blue",        QObject::tr("Simple (Blue Icons)") },    
-        { "breeze_light",   QObject::tr("Breeze Light") }, 
-        { "breeze_dark",    QObject::tr("Breeze Dark") },
-        { "OSX",            QObject::tr("OSX") },        
-        { "iOS",            QObject::tr("iOS") },          
-        { "flat",           QObject::tr("Flat") },
-        { "flat_white",     QObject::tr("Flat (White)") }, 
-        { "multimc",        QObject::tr("Legacy") },      
-        { "custom",         QObject::tr("Custom") } 
-    };
-    QList<std::pair<QString, QString>> m_catOptions{ 
-        { "kitteh",     QObject::tr("Background Cat (from MultiMC)") }, 
-        { "rory",       QObject::tr("Rory ID 11 (drawn by Ashtaka)") }, 
-        { "rory-flat",  QObject::tr("Rory ID 11 (flat edition, drawn by Ashtaka)") },
-        { "teawie",     QObject::tr("Teawie (drawn by SympathyTea)") }
-    };
+    // TODO finish implementing
+    QList<std::pair<QString, QString>> m_iconThemeOptions{ { "pe_colored", QObject::tr("Simple (Colored Icons)") },
+                                                           { "pe_light", QObject::tr("Simple (Light Icons)") },
+                                                           { "pe_dark", QObject::tr("Simple (Dark Icons)") },
+                                                           { "pe_blue", QObject::tr("Simple (Blue Icons)") },
+                                                           { "breeze_light", QObject::tr("Breeze Light") },
+                                                           { "breeze_dark", QObject::tr("Breeze Dark") },
+                                                           { "OSX", QObject::tr("OSX") },
+                                                           { "iOS", QObject::tr("iOS") },
+                                                           { "flat", QObject::tr("Flat") },
+                                                           { "flat_white", QObject::tr("Flat (White)") },
+                                                           { "multimc", QObject::tr("Legacy") },
+                                                           { "custom", QObject::tr("Custom") } };
 };