From 808b09c403f3bbecc9aaa38a3eec9baf040bf913 Mon Sep 17 00:00:00 2001
From: Trial97 <alexandru.tripon97@gmail.com>
Date: Tue, 9 Dec 2025 22:56:42 +0200
Subject: [PATCH] improve archive detection

Signed-off-by: Trial97 <alexandru.tripon97@gmail.com>
---
 launcher/InstanceImportTask.cpp    | 96 +++++++++++++++---------------
 launcher/InstanceImportTask.h      |  1 -
 launcher/archive/ArchiveReader.cpp |  2 +-
 3 files changed, 50 insertions(+), 49 deletions(-)

diff --git a/launcher/InstanceImportTask.cpp b/launcher/InstanceImportTask.cpp
index d3cc3bd02..554a563a8 100644
--- a/launcher/InstanceImportTask.cpp
+++ b/launcher/InstanceImportTask.cpp
@@ -108,70 +108,72 @@ void InstanceImportTask::downloadFromUrl()
     filesNetJob->start();
 }
 
-QString InstanceImportTask::getRootFromZip(QStringList files)
+QString cleanPath(QString path)
 {
-    if (!isRunning()) {
-        return {};
-    }
-    auto cleanPath = [](QString path) {
-        if (path == ".")
-            return QString();
-        QString result = path;
-        if (result.startsWith("./"))
-            result = result.mid(2);
-        return result;
-    };
-    for (auto&& fileName : files) {
-        setDetails(fileName);
-        QFileInfo fileInfo(fileName);
-        if (fileInfo.fileName() == "instance.cfg") {
-            qDebug() << "MultiMC:" << true;
-            m_modpackType = ModpackType::MultiMC;
-            return cleanPath(fileInfo.path());
-        }
-        if (fileInfo.fileName() == "manifest.json") {
-            qDebug() << "Flame:" << true;
-            m_modpackType = ModpackType::Flame;
-            return cleanPath(fileInfo.path());
-        }
-        QCoreApplication::processEvents();
-    }
-    return {};
+    if (path == ".")
+        return QString();
+    QString result = path;
+    if (result.startsWith("./"))
+        result = result.mid(2);
+    return result;
 }
 
 void InstanceImportTask::processZipPack()
 {
     setStatus(tr("Attempting to determine instance type"));
+    setDetails("");
     QDir extractDir(m_stagingPath);
     qDebug() << "Attempting to create instance from" << m_archivePath;
 
     // open the zip and find relevant files in it
     MMCZip::ArchiveReader packZip(m_archivePath);
-    if (!packZip.collectFiles()) {
-        emitFailed(tr("Unable to open supplied modpack zip file."));
-        return;
-    }
-
     qDebug() << "Attempting to determine instance type";
 
     QString root;
-
     // NOTE: Prioritize modpack platforms that aren't searched for recursively.
     // Especially Flame has a very common filename for its manifest, which may appear inside overrides for example
     // https://docs.modrinth.com/docs/modpacks/format_definition/#storage
-    if (packZip.exists("/modrinth.index.json")) {
-        // process as Modrinth pack
-        qDebug() << "Modrinth:" << true;
-        m_modpackType = ModpackType::Modrinth;
-    } else if (packZip.exists("/bin/modpack.jar") || packZip.exists("/bin/version.json")) {
-        // process as Technic pack
-        qDebug() << "Technic:" << true;
-        extractDir.mkpath("minecraft");
-        extractDir.cd("minecraft");
-        m_modpackType = ModpackType::Technic;
-    } else {
-        root = getRootFromZip(packZip.getFiles());
-        setDetails("");
+    auto detectInstance = [this, &extractDir, &root](MMCZip::ArchiveReader::File* f, bool& stop) {
+        if (!isRunning()) {
+            stop = true;
+            return true;
+        }
+        auto fileName = f->filename();
+        if (fileName == "/modrinth.index.json") {
+            // process as Modrinth pack
+            qDebug() << "Modrinth:" << true;
+            m_modpackType = ModpackType::Modrinth;
+            stop = true;
+        } else if (fileName == "/bin/modpack.jar" || fileName == "/bin/version.json") {
+            // process as Technic pack
+            qDebug() << "Technic:" << true;
+            extractDir.mkpath("minecraft");
+            extractDir.cd("minecraft");
+            m_modpackType = ModpackType::Technic;
+            stop = true;
+        } else {
+            QFileInfo fileInfo(fileName);
+            if (fileInfo.fileName() == "instance.cfg") {
+                qDebug() << "MultiMC:" << true;
+                m_modpackType = ModpackType::MultiMC;
+                root = cleanPath(fileInfo.path());
+                stop = true;
+                return true;
+            }
+            if (fileInfo.fileName() == "manifest.json") {
+                qDebug() << "Flame:" << true;
+                m_modpackType = ModpackType::Flame;
+                root = cleanPath(fileInfo.path());
+                stop = true;
+                return true;
+            }
+        }
+        QCoreApplication::processEvents();
+        return true;
+    };
+    if (!packZip.parse(detectInstance)) {
+        emitFailed(tr("Unable to open supplied modpack zip file."));
+        return;
     }
     if (m_modpackType == ModpackType::Unknown) {
         emitFailed(tr("Archive does not contain a recognized modpack type."));
diff --git a/launcher/InstanceImportTask.h b/launcher/InstanceImportTask.h
index 4c9e6feb5..c92e229a0 100644
--- a/launcher/InstanceImportTask.h
+++ b/launcher/InstanceImportTask.h
@@ -56,7 +56,6 @@ class InstanceImportTask : public InstanceTask {
     void processTechnic();
     void processFlame();
     void processModrinth();
-    QString getRootFromZip(QStringList files);
 
    private slots:
     void processZipPack();
diff --git a/launcher/archive/ArchiveReader.cpp b/launcher/archive/ArchiveReader.cpp
index a866b49c5..26ea9840f 100644
--- a/launcher/archive/ArchiveReader.cpp
+++ b/launcher/archive/ArchiveReader.cpp
@@ -165,7 +165,7 @@ bool ArchiveReader::parse(std::function<bool(File*, bool&)> doStuff)
 
     bool breakControl = false;
     while (f->readNextHeader() == ARCHIVE_OK) {
-        if (!doStuff(f.get(), breakControl)) {
+        if (f && !doStuff(f.get(), breakControl)) {
             qCritical() << "Failed to parse file:" << f->filename() << "-" << f->error();
             return false;
         }