Add FUSE external mapping support, BG3/Oblivion Remastered fixes, fomod-plus and NaK integration

FUSE VFS now deploys non-data-dir mod mappings (Paks, OBSE, UE4SS, etc.)
via real symlinks and injects file-level data-dir mappings (plugins.txt,
loadorder.txt) into the VFS tree. Fixes game launches for Oblivion
Remastered (Root Builder path resolution, script extender support) and
BG3 (Wine prefix documents directory, file mapper symlinks on Linux).

Vendors mo2-fomod-plus plugin and NaK crate for FOMOD installer and
game finder/runtime support.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 334 insertions, 0 deletions

diff --git a/libs/nak/src/installers/mod.rs b/libs/nak/src/installers/mod.rs
new file mode 100644
index 0000000..cf3eb85
--- /dev/null
+++ b/libs/nak/src/installers/mod.rs
@@ -0,0 +1,334 @@
+//! Mod manager installation logic
+//!
+//! Stripped for Fluorine: no common.rs, mo2.rs, plugin.rs, compatdata_scanner.rs.
+
+pub mod symlinks;
+
+mod prefix_setup;
+
+pub use prefix_setup::{
+    apply_dpi, apply_registry_for_game_path, auto_apply_game_registries, cleanup_prefix_drives,
+    install_all_dependencies, kill_wineserver, known_game_names, launch_dpi_test_app, DPI_PRESETS,
+};
+
+use std::error::Error;
+use std::fs;
+use std::sync::atomic::AtomicBool;
+use std::sync::Arc;
+
+use crate::logging::log_install;
+use crate::steam::SteamProton;
+
+// ============================================================================
+// Shared Types
+// ============================================================================
+
+/// Context for background installation tasks
+#[derive(Clone)]
+pub struct TaskContext {
+    pub status_callback: Arc<dyn Fn(String) + Send + Sync>,
+    pub log_callback: Arc<dyn Fn(String) + Send + Sync>,
+    pub progress_callback: Arc<dyn Fn(f32) + Send + Sync>,
+    pub cancel_flag: Arc<AtomicBool>,
+}
+
+impl TaskContext {
+    pub fn new(
+        status: impl Fn(String) + Send + Sync + 'static,
+        log: impl Fn(String) + Send + Sync + 'static,
+        progress: impl Fn(f32) + Send + Sync + 'static,
+        cancel: Arc<AtomicBool>,
+    ) -> Self {
+        Self {
+            status_callback: Arc::new(status),
+            log_callback: Arc::new(log),
+            progress_callback: Arc::new(progress),
+            cancel_flag: cancel,
+        }
+    }
+
+    pub fn set_status(&self, msg: String) {
+        (self.status_callback)(msg);
+    }
+
+    pub fn log(&self, msg: String) {
+        (self.log_callback)(msg);
+    }
+
+    pub fn set_progress(&self, p: f32) {
+        (self.progress_callback)(p);
+    }
+
+    pub fn is_cancelled(&self) -> bool {
+        self.cancel_flag.load(std::sync::atomic::Ordering::Relaxed)
+    }
+
+    /// Run a command that can be killed if the user cancels.
+    pub fn run_cancellable(&self, mut cmd: std::process::Command) -> Result<std::process::ExitStatus, Box<dyn std::error::Error>> {
+        let mut child = cmd.spawn()?;
+
+        loop {
+            match child.try_wait()? {
+                Some(status) => return Ok(status),
+                None => {
+                    if self.is_cancelled() {
+                        let _ = child.kill();
+                        let _ = child.wait();
+                        return Err("Cancelled".into());
+                    }
+                    std::thread::sleep(std::time::Duration::from_millis(250));
+                }
+            }
+        }
+    }
+}
+
+// ============================================================================
+// Shared Wine Registry Settings
+// ============================================================================
+
+/// Wine registry settings
+pub const WINE_SETTINGS_REG: &str = r#"Windows Registry Editor Version 5.00
+
+[HKEY_CURRENT_USER\Software\Wine\DllOverrides]
+"dwrite.dll"="native,builtin"
+"dwrite"="native,builtin"
+"winmm.dll"="native,builtin"
+"winmm"="native,builtin"
+"version.dll"="native,builtin"
+"version"="native,builtin"
+"ArchiveXL.dll"="native,builtin"
+"ArchiveXL"="native,builtin"
+"Codeware.dll"="native,builtin"
+"Codeware"="native,builtin"
+"TweakXL.dll"="native,builtin"
+"TweakXL"="native,builtin"
+"input_loader.dll"="native,builtin"
+"input_loader"="native,builtin"
+"RED4ext.dll"="native,builtin"
+"RED4ext"="native,builtin"
+"mod_settings.dll"="native,builtin"
+"mod_settings"="native,builtin"
+"scc_lib.dll"="native,builtin"
+"scc_lib"="native,builtin"
+"dxgi.dll"="native,builtin"
+"dxgi"="native,builtin"
+"dbghelp.dll"="native,builtin"
+"dbghelp"="native,builtin"
+"d3d12.dll"="native,builtin"
+"d3d12"="native,builtin"
+"wininet.dll"="native,builtin"
+"wininet"="native,builtin"
+"winhttp.dll"="native,builtin"
+"winhttp"="native,builtin"
+"dinput.dll"="native,builtin"
+"dinput8"="native,builtin"
+"dinput8.dll"="native,builtin"
+
+[HKEY_CURRENT_USER\Software\Wine]
+"ShowDotFiles"="Y"
+
+[HKEY_CURRENT_USER\Control Panel\Desktop]
+"FontSmoothing"="2"
+"FontSmoothingGamma"=dword:00000578
+"FontSmoothingOrientation"=dword:00000001
+"FontSmoothingType"=dword:00000002
+
+[HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers]
+@="~ HIGHDPIAWARE"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\Pandora Behaviour Engine+.exe\X11 Driver]
+"Decorated"="N"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\Vortex.exe\X11 Driver]
+"Decorated"="N"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\SSEEdit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\SSEEdit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\FO4Edit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\FO4Edit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\TES4Edit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\TES4Edit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xEdit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\SF1Edit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\FNVEdit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\FNVEdit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xFOEdit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xFOEdit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xSFEEdit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xSFEEdit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xTESEdit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\xTESEdit64.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\FO3Edit.exe]
+"Version"="winxp"
+
+[HKEY_CURRENT_USER\Software\Wine\AppDefaults\FO3Edit64.exe]
+"Version"="winxp"
+
+; =============================================================================
+; Native file browser integration (opens folders in native file manager)
+; =============================================================================
+[HKEY_CLASSES_ROOT\Folder\shell\explore\command]
+@="C:\\windows\\system32\\winebrowser.exe -nohome \"%1\""
+
+[HKEY_CLASSES_ROOT\Directory\shell\explore\command]
+@="C:\\windows\\system32\\winebrowser.exe -nohome \"%1\""
+
+[HKEY_CLASSES_ROOT\Folder\shell\open\command]
+@="C:\\windows\\system32\\winebrowser.exe -nohome \"%1\""
+
+[HKEY_CLASSES_ROOT\Directory\shell\open\command]
+@="C:\\windows\\system32\\winebrowser.exe -nohome \"%1\""
+
+; =============================================================================
+; Native text editor integration (opens text files in native editor)
+; =============================================================================
+[HKEY_CLASSES_ROOT\txtfile\shell\open\command]
+@="C:\\windows\\system32\\winebrowser.exe \"%1\""
+
+[HKEY_CLASSES_ROOT\inifile\shell\open\command]
+@="C:\\windows\\system32\\winebrowser.exe \"%1\""
+
+[HKEY_CLASSES_ROOT\.txt]
+@="txtfile"
+
+[HKEY_CLASSES_ROOT\.ini]
+@="inifile"
+
+[HKEY_CLASSES_ROOT\.cfg]
+@="txtfile"
+
+[HKEY_CLASSES_ROOT\.log]
+@="txtfile"
+
+[HKEY_CLASSES_ROOT\.xml]
+@="txtfile"
+
+[HKEY_CLASSES_ROOT\.json]
+@="txtfile"
+
+[HKEY_CLASSES_ROOT\.yml]
+@="txtfile"
+
+[HKEY_CLASSES_ROOT\.yaml]
+@="txtfile"
+"#;
+
+// ============================================================================
+// Shared Functions
+// ============================================================================
+
+/// Apply Wine registry settings to a prefix
+pub fn apply_wine_registry_settings(
+    prefix_path: &std::path::Path,
+    proton: &SteamProton,
+    log_callback: &impl Fn(String),
+    _app_id: Option<u32>,
+) -> Result<(), Box<dyn Error>> {
+    use std::io::Write;
+    use crate::config::AppConfig;
+    use crate::logging::{log_error, log_warning};
+    use crate::runtime_wrap;
+
+    let tmp_dir = AppConfig::get_tmp_path();
+    fs::create_dir_all(&tmp_dir)?;
+    let reg_file = tmp_dir.join("wine_settings.reg");
+
+    let mut file = fs::File::create(&reg_file)?;
+    file.write_all(WINE_SETTINGS_REG.as_bytes())?;
+
+    let wine_bin = proton.wine_binary().ok_or_else(|| {
+        let err_msg = format!(
+            "Wine binary not found for Proton '{}' (checked files/bin/wine and dist/bin/wine)",
+            proton.name
+        );
+        log_callback(format!("Error: {}", err_msg));
+        err_msg
+    })?;
+
+    let wineserver_bin = proton.wineserver_binary().unwrap_or_else(|| {
+        wine_bin.with_file_name("wineserver")
+    });
+
+    let bin_dir = proton.bin_dir().ok_or_else(|| {
+        let err_msg = "Could not determine Proton bin directory";
+        log_callback(format!("Error: {}", err_msg));
+        err_msg
+    })?;
+
+    let path_env = format!(
+        "{}:{}",
+        bin_dir.to_string_lossy(),
+        std::env::var("PATH").unwrap_or_default()
+    );
+
+    log_callback("Applying Wine registry settings...".to_string());
+    log_install("Running wine regedit...");
+
+    let reg_envs: Vec<(&str, String)> = vec![
+        ("WINEPREFIX", prefix_path.display().to_string()),
+        ("WINE", wine_bin.display().to_string()),
+        ("WINESERVER", wineserver_bin.display().to_string()),
+        ("PATH", path_env),
+        ("WINEDLLOVERRIDES", "mshtml=d".to_string()),
+        ("PROTON_USE_XALIA", "0".to_string()),
+    ];
+    let regedit_status = runtime_wrap::build_command(&wine_bin, &reg_envs)
+        .arg("regedit")
+        .arg(&reg_file)
+        .status();
+
+    match regedit_status {
+        Ok(status) => {
+            if status.success() {
+                log_callback("Registry settings applied successfully".to_string());
+                log_install("Wine registry settings applied successfully");
+            } else {
+                let msg = format!("regedit exited with code {:?}", status.code());
+                log_callback(format!("Warning: {}", msg));
+                log_warning(&msg);
+            }
+        }
+        Err(e) => {
+            let msg = format!("Failed to run regedit: {}", e);
+            log_callback(format!("Error: {}", msg));
+            log_error(&msg);
+            return Err(msg.into());
+        }
+    }
+
+    let _ = fs::remove_file(&reg_file);
+    Ok(())
+}