// SPDX-License-Identifier: GPL-3.0-only
/*
 *  Prism Launcher - Minecraft Launcher
 *  Copyright (C) 2022 Sefa Eyeoglu <contact@scrumplex.net>
 *
 *  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 <QDir>
#include <QFileInfo>
#include <QString>
#include <QStringList>

#include <settings/Setting.h>

#include <QDebug>
#include "Application.h"
#include "BuildConfig.h"
#include "FileSystem.h"
#include "java/JavaInstallList.h"
#include "java/JavaUtils.h"

#define IBUS "@im=ibus"

JavaUtils::JavaUtils() {}

QString stripVariableEntries(QString name, QString target, QString remove)
{
    char delimiter = ':';
#ifdef Q_OS_WIN32
    delimiter = ';';
#endif

    auto targetItems = target.split(delimiter);
    auto toRemove = remove.split(delimiter);

    for (QString item : toRemove) {
        bool removed = targetItems.removeOne(item);
        if (!removed)
            qWarning() << "Entry" << item << "could not be stripped from variable" << name;
    }
    return targetItems.join(delimiter);
}

QProcessEnvironment CleanEnviroment()
{
    // prepare the process environment
    QProcessEnvironment rawenv = QProcessEnvironment::systemEnvironment();
    QProcessEnvironment env;

    QStringList ignored = { "JAVA_ARGS", "CLASSPATH",     "CONFIGPATH",   "JAVA_HOME",
                            "JRE_HOME",  "_JAVA_OPTIONS", "JAVA_OPTIONS", "JAVA_TOOL_OPTIONS" };

    QStringList stripped = {
#if defined(Q_OS_LINUX) || defined(Q_OS_FREEBSD) || defined(Q_OS_OPENBSD)
        "LD_LIBRARY_PATH", "LD_PRELOAD",
#endif
        "QT_PLUGIN_PATH", "QT_FONTPATH"
    };
    for (auto key : rawenv.keys()) {
        auto value = rawenv.value(key);
        // filter out dangerous java crap
        if (ignored.contains(key)) {
            qDebug() << "Env: ignoring" << key << value;
            continue;
        }

        // These are used to strip the original variables
        // If there is "LD_LIBRARY_PATH" and "LAUNCHER_LD_LIBRARY_PATH", we want to
        // remove all values in "LAUNCHER_LD_LIBRARY_PATH" from "LD_LIBRARY_PATH"
        if (key.startsWith("LAUNCHER_")) {
            qDebug() << "Env: ignoring" << key << value;
            continue;
        }
        if (stripped.contains(key)) {
            QString newValue = stripVariableEntries(key, value, rawenv.value("LAUNCHER_" + key));

            qDebug() << "Env: stripped" << key << value << "to" << newValue;

            value = newValue;
        }
#if defined(Q_OS_LINUX) || defined(Q_OS_FREEBSD) || defined(Q_OS_OPENBSD)
        // Strip IBus
        // IBus is a Linux IME framework. For some reason, it breaks MC?
        if (key == "XMODIFIERS" && value.contains(IBUS)) {
            QString save = value;
            value.replace(IBUS, "");
            qDebug() << "Env: stripped" << IBUS << "from" << save << ":" << value;
        }
#endif
        // qDebug() << "Env: " << key << value;
        env.insert(key, value);
    }
#ifdef Q_OS_LINUX
    // HACK: Workaround for QTBUG-42500
    if (!env.contains("LD_LIBRARY_PATH")) {
        env.insert("LD_LIBRARY_PATH", "");
    }
#endif

    return env;
}

JavaInstallPtr JavaUtils::MakeJavaPtr(QString path, QString id, QString arch)
{
    JavaInstallPtr javaVersion(new JavaInstall());

    javaVersion->id = id;
    javaVersion->arch = arch;
    javaVersion->path = path;

    return javaVersion;
}

JavaInstallPtr JavaUtils::GetDefaultJava()
{
    JavaInstallPtr javaVersion(new JavaInstall());

    javaVersion->id = "java";
    javaVersion->arch = "unknown";
#if defined(Q_OS_WIN32)
    javaVersion->path = "javaw";
#else
    javaVersion->path = "java";
#endif

    return javaVersion;
}

QStringList addJavasFromEnv(QList<QString> javas)
{
    auto env = QProcessEnvironment::systemEnvironment().value(QStringLiteral("%1_JAVA_PATHS").arg(BuildConfig.LAUNCHER_ENVNAME));
#if defined(Q_OS_WIN32)
    QList<QString> javaPaths = env.replace("\\", "/").split(QLatin1String(";"));

    auto envPath = qEnvironmentVariable("PATH");
    QList<QString> javaPathsfromPath = envPath.replace("\\", "/").split(QLatin1String(";"));
    for (QString string : javaPathsfromPath) {
        javaPaths.append(string + "/javaw.exe");
    }
#else
    QList<QString> javaPaths = env.split(QLatin1String(":"));
#endif
    for (QString i : javaPaths) {
        javas.append(i);
    };
    return javas;
}

#if defined(Q_OS_WIN32)
QList<JavaInstallPtr> JavaUtils::FindJavaFromRegistryKey(DWORD keyType, QString keyName, QString keyJavaDir, QString subkeySuffix)
{
    QList<JavaInstallPtr> javas;

    QString archType = "unknown";
    if (keyType == KEY_WOW64_64KEY)
        archType = "64";
    else if (keyType == KEY_WOW64_32KEY)
        archType = "32";

    for (HKEY baseRegistry : { HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE }) {
        HKEY jreKey;
        if (RegOpenKeyExW(baseRegistry, keyName.toStdWString().c_str(), 0, KEY_READ | keyType | KEY_ENUMERATE_SUB_KEYS, &jreKey) ==
            ERROR_SUCCESS) {
            // Read the current type version from the registry.
            // This will be used to find any key that contains the JavaHome value.

            WCHAR subKeyName[255];
            DWORD subKeyNameSize, numSubKeys, retCode;

            // Get the number of subkeys
            RegQueryInfoKeyW(jreKey, NULL, NULL, NULL, &numSubKeys, NULL, NULL, NULL, NULL, NULL, NULL, NULL);

            // Iterate until RegEnumKeyEx fails
            if (numSubKeys > 0) {
                for (DWORD i = 0; i < numSubKeys; i++) {
                    subKeyNameSize = 255;
                    retCode = RegEnumKeyExW(jreKey, i, subKeyName, &subKeyNameSize, NULL, NULL, NULL, NULL);
                    QString newSubkeyName = QString::fromWCharArray(subKeyName);
                    if (retCode == ERROR_SUCCESS) {
                        // Now open the registry key for the version that we just got.
                        QString newKeyName = keyName + "\\" + newSubkeyName + subkeySuffix;

                        HKEY newKey;
                        if (RegOpenKeyExW(baseRegistry, newKeyName.toStdWString().c_str(), 0, KEY_READ | keyType, &newKey) ==
                            ERROR_SUCCESS) {
                            // Read the JavaHome value to find where Java is installed.
                            DWORD valueSz = 0;
                            if (RegQueryValueExW(newKey, keyJavaDir.toStdWString().c_str(), NULL, NULL, NULL, &valueSz) == ERROR_SUCCESS) {
                                WCHAR* value = new WCHAR[valueSz];
                                RegQueryValueExW(newKey, keyJavaDir.toStdWString().c_str(), NULL, NULL, (BYTE*)value, &valueSz);

                                QString newValue = QString::fromWCharArray(value);
                                delete[] value;

                                // Now, we construct the version object and add it to the list.
                                JavaInstallPtr javaVersion(new JavaInstall());

                                javaVersion->id = newSubkeyName;
                                javaVersion->arch = archType;
                                javaVersion->path = QDir(FS::PathCombine(newValue, "bin")).absoluteFilePath("javaw.exe");
                                javas.append(javaVersion);
                            }

                            RegCloseKey(newKey);
                        }
                    }
                }
            }

            RegCloseKey(jreKey);
        }
    }

    return javas;
}

QList<QString> JavaUtils::FindJavaPaths()
{
    QList<JavaInstallPtr> java_candidates;

    // Oracle
    QList<JavaInstallPtr> JRE64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\JavaSoft\\Java Runtime Environment", "JavaHome");
    QList<JavaInstallPtr> JDK64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\JavaSoft\\Java Development Kit", "JavaHome");
    QList<JavaInstallPtr> JRE32s =
        this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\JavaSoft\\Java Runtime Environment", "JavaHome");
    QList<JavaInstallPtr> JDK32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\JavaSoft\\Java Development Kit", "JavaHome");

    // Oracle for Java 9 and newer
    QList<JavaInstallPtr> NEWJRE64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\JavaSoft\\JRE", "JavaHome");
    QList<JavaInstallPtr> NEWJDK64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\JavaSoft\\JDK", "JavaHome");
    QList<JavaInstallPtr> NEWJRE32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\JavaSoft\\JRE", "JavaHome");
    QList<JavaInstallPtr> NEWJDK32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\JavaSoft\\JDK", "JavaHome");

    // AdoptOpenJDK
    QList<JavaInstallPtr> ADOPTOPENJRE32s =
        this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\AdoptOpenJDK\\JRE", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> ADOPTOPENJRE64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\AdoptOpenJDK\\JRE", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> ADOPTOPENJDK32s =
        this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\AdoptOpenJDK\\JDK", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> ADOPTOPENJDK64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\AdoptOpenJDK\\JDK", "Path", "\\hotspot\\MSI");

    // Eclipse Foundation
    QList<JavaInstallPtr> FOUNDATIONJDK32s =
        this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\Eclipse Foundation\\JDK", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> FOUNDATIONJDK64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Eclipse Foundation\\JDK", "Path", "\\hotspot\\MSI");

    // Eclipse Adoptium
    QList<JavaInstallPtr> ADOPTIUMJRE32s =
        this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\Eclipse Adoptium\\JRE", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> ADOPTIUMJRE64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Eclipse Adoptium\\JRE", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> ADOPTIUMJDK32s =
        this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\Eclipse Adoptium\\JDK", "Path", "\\hotspot\\MSI");
    QList<JavaInstallPtr> ADOPTIUMJDK64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Eclipse Adoptium\\JDK", "Path", "\\hotspot\\MSI");

    // IBM Semeru
    QList<JavaInstallPtr> SEMERUJRE32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\Semeru\\JRE", "Path", "\\openj9\\MSI");
    QList<JavaInstallPtr> SEMERUJRE64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Semeru\\JRE", "Path", "\\openj9\\MSI");
    QList<JavaInstallPtr> SEMERUJDK32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\Semeru\\JDK", "Path", "\\openj9\\MSI");
    QList<JavaInstallPtr> SEMERUJDK64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Semeru\\JDK", "Path", "\\openj9\\MSI");

    // Microsoft
    QList<JavaInstallPtr> MICROSOFTJDK64s =
        this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Microsoft\\JDK", "Path", "\\hotspot\\MSI");

    // Azul Zulu
    QList<JavaInstallPtr> ZULU64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\Azul Systems\\Zulu", "InstallationPath");
    QList<JavaInstallPtr> ZULU32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\Azul Systems\\Zulu", "InstallationPath");

    // BellSoft Liberica
    QList<JavaInstallPtr> LIBERICA64s = this->FindJavaFromRegistryKey(KEY_WOW64_64KEY, "SOFTWARE\\BellSoft\\Liberica", "InstallationPath");
    QList<JavaInstallPtr> LIBERICA32s = this->FindJavaFromRegistryKey(KEY_WOW64_32KEY, "SOFTWARE\\BellSoft\\Liberica", "InstallationPath");

    // List x64 before x86
    java_candidates.append(JRE64s);
    java_candidates.append(NEWJRE64s);
    java_candidates.append(ADOPTOPENJRE64s);
    java_candidates.append(ADOPTIUMJRE64s);
    java_candidates.append(SEMERUJRE64s);
    java_candidates.append(MakeJavaPtr("C:/Program Files/Java/jre8/bin/javaw.exe"));
    java_candidates.append(MakeJavaPtr("C:/Program Files/Java/jre7/bin/javaw.exe"));
    java_candidates.append(MakeJavaPtr("C:/Program Files/Java/jre6/bin/javaw.exe"));
    java_candidates.append(JDK64s);
    java_candidates.append(NEWJDK64s);
    java_candidates.append(ADOPTOPENJDK64s);
    java_candidates.append(FOUNDATIONJDK64s);
    java_candidates.append(ADOPTIUMJDK64s);
    java_candidates.append(SEMERUJDK64s);
    java_candidates.append(MICROSOFTJDK64s);
    java_candidates.append(ZULU64s);
    java_candidates.append(LIBERICA64s);

    java_candidates.append(JRE32s);
    java_candidates.append(NEWJRE32s);
    java_candidates.append(ADOPTOPENJRE32s);
    java_candidates.append(ADOPTIUMJRE32s);
    java_candidates.append(SEMERUJRE32s);
    java_candidates.append(MakeJavaPtr("C:/Program Files (x86)/Java/jre8/bin/javaw.exe"));
    java_candidates.append(MakeJavaPtr("C:/Program Files (x86)/Java/jre7/bin/javaw.exe"));
    java_candidates.append(MakeJavaPtr("C:/Program Files (x86)/Java/jre6/bin/javaw.exe"));
    java_candidates.append(JDK32s);
    java_candidates.append(NEWJDK32s);
    java_candidates.append(ADOPTOPENJDK32s);
    java_candidates.append(FOUNDATIONJDK32s);
    java_candidates.append(ADOPTIUMJDK32s);
    java_candidates.append(SEMERUJDK32s);
    java_candidates.append(ZULU32s);
    java_candidates.append(LIBERICA32s);

    java_candidates.append(MakeJavaPtr(this->GetDefaultJava()->path));

    QList<QString> candidates;
    for (JavaInstallPtr java_candidate : java_candidates) {
        if (!candidates.contains(java_candidate->path)) {
            candidates.append(java_candidate->path);
        }
    }

    candidates.append(getMinecraftJavaBundle());
    candidates.append(getPrismJavaBundle());
    candidates = addJavasFromEnv(candidates);
    candidates.removeDuplicates();
    return candidates;
}

#elif defined(Q_OS_MAC)
QList<QString> JavaUtils::FindJavaPaths()
{
    QList<QString> javas;
    javas.append(this->GetDefaultJava()->path);
    javas.append("/Applications/Xcode.app/Contents/Applications/Application Loader.app/Contents/MacOS/itms/java/bin/java");
    javas.append("/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin/java");
    javas.append("/System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/java");
    QDir libraryJVMDir("/Library/Java/JavaVirtualMachines/");
    QStringList libraryJVMJavas = libraryJVMDir.entryList(QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QString& java : libraryJVMJavas) {
        javas.append(libraryJVMDir.absolutePath() + "/" + java + "/Contents/Home/bin/java");
        javas.append(libraryJVMDir.absolutePath() + "/" + java + "/Contents/Home/jre/bin/java");
    }
    QDir systemLibraryJVMDir("/System/Library/Java/JavaVirtualMachines/");
    QStringList systemLibraryJVMJavas = systemLibraryJVMDir.entryList(QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QString& java : systemLibraryJVMJavas) {
        javas.append(systemLibraryJVMDir.absolutePath() + "/" + java + "/Contents/Home/bin/java");
        javas.append(systemLibraryJVMDir.absolutePath() + "/" + java + "/Contents/Commands/java");
    }

    auto home = qEnvironmentVariable("HOME");

    // javas downloaded by sdkman
    QString sdkmanDir = qEnvironmentVariable("SDKMAN_DIR", FS::PathCombine(home, ".sdkman"));
    QDir sdkmanJavaDir(FS::PathCombine(sdkmanDir, "candidates/java"));
    QStringList sdkmanJavas = sdkmanJavaDir.entryList(QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QString& java : sdkmanJavas) {
        javas.append(sdkmanJavaDir.absolutePath() + "/" + java + "/bin/java");
    }

    // javas downloaded by asdf
    QString asdfDataDir = qEnvironmentVariable("ASDF_DATA_DIR", FS::PathCombine(home, ".asdf"));
    QDir asdfJavaDir(FS::PathCombine(asdfDataDir, "installs/java"));
    QStringList asdfJavas = asdfJavaDir.entryList(QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QString& java : asdfJavas) {
        javas.append(asdfJavaDir.absolutePath() + "/" + java + "/bin/java");
    }

    // java in user library folder (like from intellij downloads)
    QDir userLibraryJVMDir(FS::PathCombine(home, "Library/Java/JavaVirtualMachines/"));
    QStringList userLibraryJVMJavas = userLibraryJVMDir.entryList(QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QString& java : userLibraryJVMJavas) {
        javas.append(userLibraryJVMDir.absolutePath() + "/" + java + "/Contents/Home/bin/java");
        javas.append(userLibraryJVMDir.absolutePath() + "/" + java + "/Contents/Commands/java");
    }

    javas.append(getMinecraftJavaBundle());
    javas.append(getPrismJavaBundle());
    javas = addJavasFromEnv(javas);
    javas.removeDuplicates();
    return javas;
}

#elif defined(Q_OS_LINUX) || defined(Q_OS_OPENBSD) || defined(Q_OS_FREEBSD)
QList<QString> JavaUtils::FindJavaPaths()
{
    QList<QString> javas;
    javas.append(this->GetDefaultJava()->path);
    auto scanJavaDir = [&javas](
                           const QString& dirPath,
                           const std::function<bool(const QFileInfo&)>& filter = [](const QFileInfo&) { return true; }) {
        QDir dir(dirPath);
        if (!dir.exists())
            return;
        auto entries = dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
        for (auto& entry : entries) {
            if (!filter(entry))
                continue;

            QString prefix;
            prefix = entry.canonicalFilePath();
            javas.append(FS::PathCombine(prefix, "jre/bin/java"));
            javas.append(FS::PathCombine(prefix, "bin/java"));
        }
    };
    // java installed in a snap is installed in the standard directory, but underneath $SNAP
    auto snap = qEnvironmentVariable("SNAP");
    auto scanJavaDirs = [scanJavaDir, snap](const QString& dirPath) {
        scanJavaDir(dirPath);
        if (!snap.isNull()) {
            scanJavaDir(snap + dirPath);
        }
    };
#if defined(Q_OS_LINUX)
    // oracle RPMs
    scanJavaDirs("/usr/java");
    // general locations used by distro packaging
    scanJavaDirs("/usr/lib/jvm");
    scanJavaDirs("/usr/lib64/jvm");
    scanJavaDirs("/usr/lib32/jvm");
    // Gentoo's locations for openjdk and openjdk-bin respectively
    auto gentooFilter = [](const QFileInfo& info) {
        QString fileName = info.fileName();
        return fileName.startsWith("openjdk-") || fileName.startsWith("openj9-");
    };
    // AOSC OS's locations for openjdk
    auto aoscFilter = [](const QFileInfo& info) {
        QString fileName = info.fileName();
        return fileName == "java" || fileName.startsWith("java-");
    };
    scanJavaDir("/usr/lib64", gentooFilter);
    scanJavaDir("/usr/lib", gentooFilter);
    scanJavaDir("/opt", gentooFilter);
    scanJavaDir("/usr/lib", aoscFilter);
    // javas stored in Prism Launcher's folder
    scanJavaDirs("java");
    // manually installed JDKs in /opt
    scanJavaDirs("/opt/jdk");
    scanJavaDirs("/opt/jdks");
    scanJavaDirs("/opt/ibm");  // IBM Semeru Certified Edition
    // flatpak
    scanJavaDirs("/app/jdk");
#elif defined(Q_OS_OPENBSD) || defined(Q_OS_FREEBSD)
    // ports install to /usr/local on OpenBSD & FreeBSD
    scanJavaDirs("/usr/local");
#endif
    auto home = qEnvironmentVariable("HOME");

    // javas downloaded by IntelliJ
    scanJavaDirs(FS::PathCombine(home, ".jdks"));
    // javas downloaded by sdkman
    QString sdkmanDir = qEnvironmentVariable("SDKMAN_DIR", FS::PathCombine(home, ".sdkman"));
    scanJavaDirs(FS::PathCombine(sdkmanDir, "candidates/java"));
    // javas downloaded by asdf
    QString asdfDataDir = qEnvironmentVariable("ASDF_DATA_DIR", FS::PathCombine(home, ".asdf"));
    scanJavaDirs(FS::PathCombine(asdfDataDir, "installs/java"));
    // javas downloaded by gradle (toolchains)
    QString gradleUserHome = qEnvironmentVariable("GRADLE_USER_HOME", FS::PathCombine(home, ".gradle"));
    scanJavaDirs(FS::PathCombine(gradleUserHome, "jdks"));

    javas.append(getMinecraftJavaBundle());
    javas.append(getPrismJavaBundle());
    javas = addJavasFromEnv(javas);
    javas.removeDuplicates();
    return javas;
}
#else
QList<QString> JavaUtils::FindJavaPaths()
{
    qDebug() << "Unknown operating system build - defaulting to \"java\"";

    QList<QString> javas;
    javas.append(this->GetDefaultJava()->path);

    javas.append(getMinecraftJavaBundle());
    javas.append(getPrismJavaBundle());
    javas.removeDuplicates();
    return addJavasFromEnv(javas);
}
#endif

QString JavaUtils::getJavaCheckPath()
{
    return APPLICATION->getJarPath("JavaCheck.jar");
}

QStringList getMinecraftJavaBundle()
{
    QStringList processpaths;
#if defined(Q_OS_MACOS)
    processpaths << FS::PathCombine(QDir::homePath(), FS::PathCombine("Library", "Application Support", "minecraft", "runtime"));
#elif defined(Q_OS_WIN32)

    auto appDataPath = QProcessEnvironment::systemEnvironment().value("APPDATA", "");
    processpaths << FS::PathCombine(QFileInfo(appDataPath).absoluteFilePath(), ".minecraft", "runtime");

    // add the microsoft store version of the launcher to the search. the current path is:
    // C:\Users\USERNAME\AppData\Local\Packages\Microsoft.4297127D64EC6_8wekyb3d8bbwe\LocalCache\Local\runtime
    auto localAppDataPath = QProcessEnvironment::systemEnvironment().value("LOCALAPPDATA", "");
    auto minecraftMSStorePath =
        FS::PathCombine(QFileInfo(localAppDataPath).absoluteFilePath(), "Packages", "Microsoft.4297127D64EC6_8wekyb3d8bbwe");
    processpaths << FS::PathCombine(minecraftMSStorePath, "LocalCache", "Local", "runtime");
#else
    processpaths << FS::PathCombine(QDir::homePath(), ".minecraft", "runtime");
#endif

    QStringList javas;
    while (!processpaths.isEmpty()) {
        auto dirPath = processpaths.takeFirst();
        QDir dir(dirPath);
        if (!dir.exists())
            continue;
        auto entries = dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
        auto binFound = false;
        for (auto& entry : entries) {
            if (entry.baseName() == "bin") {
                javas.append(FS::PathCombine(entry.canonicalFilePath(), JavaUtils::javaExecutable));
                binFound = true;
                break;
            }
        }
        if (!binFound) {
            for (auto& entry : entries) {
                processpaths << entry.canonicalFilePath();
            }
        }
    }
    return javas;
}

#if defined(Q_OS_WIN32)
const QString JavaUtils::javaExecutable = "javaw.exe";
#else
const QString JavaUtils::javaExecutable = "java";
#endif

QStringList getPrismJavaBundle()
{
    QList<QString> javas;

    auto scanDir = [&javas](QString prefix) {
        javas.append(FS::PathCombine(prefix, "jre", "bin", JavaUtils::javaExecutable));
        javas.append(FS::PathCombine(prefix, "bin", JavaUtils::javaExecutable));
        javas.append(FS::PathCombine(prefix, JavaUtils::javaExecutable));
    };
    auto scanJavaDir = [scanDir](const QString& dirPath) {
        QDir dir(dirPath);
        if (!dir.exists())
            return;
        auto entries = dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
        for (auto& entry : entries) {
            scanDir(entry.canonicalFilePath());
        }
    };

    scanJavaDir(APPLICATION->javaPath());

    return javas;
}
