first commit

watcher/watcher.go

@@ -0,0 +1,60 @@
+package watcher
+
+import (
+	"context"
+	"log/slog"
+	"os"
+	"path/filepath"
+
+	"git.savin.nyc/alex/go-iar-notificator/bus"
+	"github.com/fsnotify/fsnotify"
+)
+
+const (
+	EventNewMP3 = "new_mp3" // Event name for new MP3 detection
+)
+
+func WatchDirectory(ctx context.Context, dirToWatch string, eb *bus.CustomEventBus, logger *slog.Logger) {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		logger.Error("Failed to create directory watcher", "error", err)
+		return
+	}
+	defer watcher.Close()
+
+	// Ensure the directory exists
+	if err := os.MkdirAll(dirToWatch, os.ModePerm); err != nil {
+		logger.Error("Failed to create watched directory", "error", err, "dir", dirToWatch)
+		return
+	}
+
+	if err := watcher.Add(dirToWatch); err != nil {
+		logger.Error("Failed to add watch on directory", "error", err, "dir", dirToWatch)
+		return
+	}
+
+	logger.Info("Watching directory for MP3 files", "dir", dirToWatch)
+
+	for {
+		select {
+		case <-ctx.Done():
+			logger.Info("Stopping directory watcher")
+			return
+		case event, ok := <-watcher.Events:
+			if !ok {
+				return
+			}
+			// Trigger on file creation or write (e.g., when saved)
+			if (event.Op&fsnotify.Create == fsnotify.Create || event.Op&fsnotify.Write == fsnotify.Write) &&
+				filepath.Ext(event.Name) == ".mp3" {
+				logger.Info("Detected new or saved MP3 file", "path", event.Name)
+				eb.Publish(EventNewMP3, event.Name)
+			}
+		case err, ok := <-watcher.Errors:
+			if !ok {
+				return
+			}
+			logger.Error("Directory watcher error", "error", err)
+		}
+	}
+}