1 files changed, 99 insertions, 0 deletions
diff --git a/libs/nak/src/logging.rs b/libs/nak/src/logging.rs
new file mode 100644
index 0000000..8c0f91a
--- /dev/null
+++ b/libs/nak/src/logging.rs
@@ -0,0 +1,99 @@
+//! Logging for Fluorine Manager.
+//!
+//! All log messages are:
+//! 1. Written to `~/.var/app/com.fluorine.manager/logs/nak.log` (always)
+//! 2. Forwarded to an optional callback set via `set_log_callback()` (for MOBase::log)
+
+use std::fs;
+use std::io::Write;
+use std::path::PathBuf;
+use std::sync::Mutex;
+
+/// Signature for the log callback: (level, message)
+///
+/// Levels: "info", "warning", "error", "install", "action", "download"
+type LogCallback = Box<dyn Fn(&str, &str) + Send + Sync>;
+
+static LOG_CALLBACK: Mutex<Option<LogCallback>> = Mutex::new(None);
+
+/// Set the global log callback. Call once at startup from FFI.
+pub fn set_log_callback(cb: impl Fn(&str, &str) + Send + Sync + 'static) {
+    if let Ok(mut guard) = LOG_CALLBACK.lock() {
+        *guard = Some(Box::new(cb));
+    }
+}
+
+/// Get the log directory path.
+fn log_dir() -> PathBuf {
+    let home = std::env::var("HOME").unwrap_or_else(|_| "/tmp".to_string());
+    PathBuf::from(home).join(".var/app/com.fluorine.manager/logs")
+}
+
+/// Get the log file path.
+fn log_file_path() -> PathBuf {
+    log_dir().join("nak.log")
+}
+
+fn emit(level: &str, message: &str) {
+    // Write to file (always, even before callback is set)
+    write_to_file(level, message);
+
+    // Forward to callback if set
+    if let Ok(guard) = LOG_CALLBACK.lock() {
+        if let Some(ref cb) = *guard {
+            cb(level, message);
+        }
+    }
+}
+
+fn write_to_file(level: &str, message: &str) {
+    let path = log_file_path();
+
+    // Ensure log directory exists (only try once per message, cheap no-op if exists)
+    if let Some(parent) = path.parent() {
+        let _ = fs::create_dir_all(parent);
+    }
+
+    // Rotate if over 2MB
+    if let Ok(meta) = fs::metadata(&path) {
+        if meta.len() > 2 * 1024 * 1024 {
+            let old = path.with_extension("log.old");
+            let _ = fs::rename(&path, &old);
+        }
+    }
+
+    let Ok(mut file) = fs::OpenOptions::new()
+        .create(true)
+        .append(true)
+        .open(&path)
+    else {
+        return;
+    };
+
+    let timestamp = chrono::Local::now().format("%H:%M:%S");
+    let _ = writeln!(file, "[{}] [{}] {}", timestamp, level.to_uppercase(), message);
+}
+
+pub fn log_info(message: &str) {
+    emit("info", message);
+}
+
+pub fn log_warning(message: &str) {
+    emit("warning", message);
+}
+
+pub fn log_error(message: &str) {
+    emit("error", message);
+}
+
+pub fn log_install(message: &str) {
+    emit("install", message);
+}
+
+pub fn log_action(message: &str) {
+    emit("action", message);
+}
+
+pub fn log_download(message: &str) {
+    emit("download", message);
+}