[frontend] Unify cmdline parsing (#4424)

Addresses #4383.

Makes it so both the Qt and SDL frontends now share the same options (bar `-hlaunch` and `-qlaunch`).

Signed-off-by: lizzie <lizzie@eden-emu.dev>

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4424
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: Maufeat <sahyno1996@gmail.com>

1 files changed, 18 insertions, 68 deletions

diff --git a/src/yuzu/main_window.cpp b/src/yuzu/main_window.cpp
index 1d579239a1..e2807e80ff 100644
--- a/src/yuzu/main_window.cpp
+++ b/src/yuzu/main_window.cpp
@@ -3,6 +3,7 @@
 
 // Static Qt on macOS doesn't use Vulkan
 // Other platforms do, and thus have conflicting VulkanMemoryAllocator symbols
+#include "core/launch_params.h"
 #if defined(QT_STATICPLUGIN) && !defined(__APPLE__)
 #undef VMA_IMPLEMENTATION
 #endif
@@ -515,79 +516,28 @@ MainWindow::MainWindow(bool has_broken_vulkan)
     // to prevent the UI from blowing up.
     UpdateUITheme();
 
-    QStringList args = QApplication::arguments();
+    if (QStringList args = QApplication::arguments(); args.size() >= 2) {
+        QList<QByteArray> qba{};
+        for (auto const& e : args)
+            qba.push_back(e.toUtf8());
+        std::vector<char*> args_cstr{};
+        for (auto& e : qba)
+            args_cstr.push_back(e.data());
 
-    if (args.size() < 2) {
-        return;
-    }
+        auto const lp = Core::ParseLaunchParams(*QtCommon::system, args_cstr.size(), args_cstr.data(), nullptr);
 
-    QString game_path;
-    bool should_launch_qlaunch = false;
-    bool should_launch_hlaunch = false;
-    bool should_launch_setup = false;
-    bool has_gamepath = false;
-    bool is_fullscreen = false;
-
-    // Preserves drag/drop functionality
-    for (int i = 1; i < args.size(); ++i) {
-        if (args[i] == QStringLiteral("-f")) {
-            // Launch game in fullscreen mode
-            is_fullscreen = true;
-        } else if (args[i] == QStringLiteral("-u") && i < args.size() - 1) {
-            // Launch game with a specific user
-            int user_arg_idx = ++i;
-            bool argument_ok;
-            std::size_t selected_user = args[user_arg_idx].toUInt(&argument_ok);
-            if (!argument_ok) {
-                // try to look it up by username, only finds the first username that matches.
-                std::string const user_arg_str = args[user_arg_idx].toStdString();
-                auto const user_idx =
-                    QtCommon::system->GetProfileManager().GetUserIndex(user_arg_str);
-                if (user_idx != std::nullopt) {
-                    selected_user = user_idx.value();
-                } else {
-                    LOG_ERROR(Frontend, "Invalid user argument '{}'", user_arg_str);
-                    continue;
-                }
-            }
-            if (QtCommon::system->GetProfileManager().UserExistsIndex(selected_user)) {
-                Settings::values.current_user = s32(selected_user);
-                user_flag_cmd_line = true;
-            } else {
-                LOG_ERROR(Frontend, "Selected user {} doesn't exist", selected_user);
-            }
-        } else if (args[i] == QStringLiteral("-g") && i < args.size() - 1) {
-            // Launch game at path
-            game_path = args[++i];
-            has_gamepath = true;
-        } else if (args[i] == QStringLiteral("-input-profile") && i < args.size() - 1) {
-            auto& players = Settings::values.players.GetValue();
-            players[0].profile_name = args[++i].toStdString();
-        } else if (args[i] == QStringLiteral("-qlaunch")) {
-            should_launch_qlaunch = true;
-        } else if (args[i] == QStringLiteral("-hlaunch")) {
-            should_launch_hlaunch = true;
-        } else if (args[i] == QStringLiteral("-setup")) {
-            should_launch_setup = true;
-        } else {
-            game_path = args[i];
-            has_gamepath = true;
+        // Override fullscreen setting if gamepath or argument is provided
+        if (!lp.filepath.empty() || lp.fullscreen) {
+            ui->action_Fullscreen->setChecked(lp.fullscreen);
         }
-    }
 
-    // Override fullscreen setting if gamepath or argument is provided
-    if (has_gamepath || is_fullscreen) {
-        ui->action_Fullscreen->setChecked(is_fullscreen);
-    }
-
-    if (should_launch_setup) {
-        LaunchFirmwareApplet(u64(Service::AM::AppletProgramId::Starter), std::nullopt);
-    } else {
-        if (!game_path.isEmpty()) {
-            BootGame(game_path, ApplicationAppletParameters());
-        } else if (should_launch_qlaunch) {
+        if (!lp.filepath.empty()) {
+            BootGame(QString::fromStdString(lp.filepath), ApplicationAppletParameters());
+        } else if (lp.launch_setup) {
+            LaunchFirmwareApplet(u64(Service::AM::AppletProgramId::Starter), std::nullopt);
+        } else if (lp.launch_qlaunch) {
             LaunchFirmwareApplet(u64(Service::AM::AppletProgramId::QLaunch), std::nullopt);
-        } else if (should_launch_hlaunch) {
+        } else if (lp.launch_hlaunch) {
             std::filesystem::path const sd_dir =
                 Common::FS::GetEdenPathString(Common::FS::EdenPath::SDMCDir);
             auto const hbl_path = (sd_dir / "atmosphere" / "hbl.nsp").string();