Improve OS detection and add APPIMAGE support to pathing code (#1003)

* Added get_app_path, tweaked pathing to adjust itself for Linux, ...

* Added get_app_path
  * This should be used instead of QCoreApplication::applicationDirPath()
* Tweaked pathing to adjust itself for Linux

* Append separator to base path

* Moved headers where they are needed. (Dunno why they were here.)

* Proper pathing for AppImage

src/file_functions.cpp

@@ -1,5 +1,9 @@
 #include "file_functions.h"
 
+#include <QCoreApplication>
+#include <QDir>
+#include <QFileInfo>
+
 bool file_exists(QString file_path)
 {
   if (file_path.isEmpty())
@@ -31,24 +35,47 @@ bool exists(QString p_path)
   return file.exists();
 }
 
-QString get_base_path()
+QString get_app_path()
 {
-  QString base_path;
-#ifdef ANDROID
-  QString sdcard_storage = getenv("SECONDARY_STORAGE");
-  if (dir_exists(sdcard_storage + "/base/"))
+  QString path = QCoreApplication::applicationDirPath();
+
+#ifdef Q_OS_ANDROID
+  QString storage_path = qgetenv("SECONDARY_STORAGE");
+  if (dir_exists(storage_path))
   {
-    base_path = sdcard_storage + "/base/";
+    path = storage_path;
   }
   else
   {
-    QString external_storage = getenv("EXTERNAL_STORAGE");
-    base_path = external_storage + "/base/";
+    QString external_path = qgetenv("EXTERNAL_STORAGE");
+    if (dir_exists(external_path))
+    {
+      path = external_path;
+    }
   }
-#elif defined(__APPLE__)
-  base_path = QCoreApplication::applicationDirPath() + "/../../../base/";
-#else
-  base_path = QCoreApplication::applicationDirPath() + "/base/";
 #endif
-  return base_path;
+
+#ifdef Q_OS_LINUX
+  QString app_path = qgetenv("APPIMAGE");
+  if (!app_path.isEmpty())
+  {
+    path = QFileInfo(app_path).absoluteDir().path();
+  }
+#endif
+
+#ifdef Q_OS_MAC
+  path += "/../../..";
+#endif
+
+  if (path.endsWith(QDir::separator()))
+  {
+    path.chop(1);
+  }
+
+  return path;
+}
+
+QString get_base_path()
+{
+  return QDir(get_app_path()).absoluteFilePath("base") + "/";
 }

src/file_functions.h

@@ -1,11 +1,10 @@
 #pragma once
 
-#include <QCoreApplication>
-#include <QDir>
-#include <QFileInfo>
 #include <QString>
 
 bool file_exists(QString file_path);
 bool dir_exists(QString file_path);
 bool exists(QString p_path);
+
+QString get_app_path();
 QString get_base_path();

src/lobby.cpp

@@ -425,7 +425,7 @@ void Lobby::on_demo_clicked(QTreeWidgetItem *item, int column)
     return;
   }
 
-  QString l_filepath = (QApplication::applicationDirPath() + "/logs/%1/%2").arg(item->data(0, Qt::DisplayRole).toString(), item->data(1, Qt::DisplayRole).toString());
+  QString l_filepath = (get_app_path() + "/logs/%1/%2").arg(item->data(0, Qt::DisplayRole).toString(), item->data(1, Qt::DisplayRole).toString());
   ao_app->demo_server->start_server();
   ServerInfo demo_server;
   demo_server.ip = "127.0.0.1";

src/text_file_functions.cpp

@@ -133,7 +133,7 @@ bool AOApplication::append_to_file(QString p_text, QString p_file, bool make_dir
 
 QMultiMap<QString, QString> AOApplication::load_demo_logs_list() const
 {
-  QString l_log_path = applicationDirPath() + "/logs/";
+  QString l_log_path = get_app_path() + "/logs/";
   QDir l_log_folder(l_log_path);
   l_log_folder.setFilter(QDir::NoDotAndDotDot | QDir::Dirs);
 

src/widgets/aooptionsdialog.cpp

@@ -436,12 +436,12 @@ void AOOptionsDialog::setupUI()
 
   FROM_UI(QPushButton, mount_add);
   connect(ui_mount_add, &QPushButton::clicked, this, [this] {
-    QString path = QFileDialog::getExistingDirectory(this, tr("Select a base folder"), QApplication::applicationDirPath(), QFileDialog::ShowDirsOnly);
+    QString path = QFileDialog::getExistingDirectory(this, tr("Select a base folder"), get_app_path(), QFileDialog::ShowDirsOnly);
     if (path.isEmpty())
     {
       return;
     }
-    QDir dir(QApplication::applicationDirPath());
+    QDir dir(get_app_path());
     QString relative = dir.relativeFilePath(path);
     if (!relative.contains("../"))
     {