chore: rename and better comments

Signed-off-by: gfanton <8671905+gfanton@users.noreply.github.com>

contribs/gnodev/pkg/watcher/watch.go

@@ -19,32 +19,15 @@ type PackageWatcher struct {
 	PackagesUpdate <-chan PackageUpdateList
 	Errors         <-chan error
 
+	ctx  context.Context
+	stop context.CancelFunc
+
 	logger  log.Logger
 	watcher *fsnotify.Watcher
-	pkgs    []string
-	ctx     context.Context
-	stop    context.CancelFunc
+	pkgsDir []string
 	emitter events.Emitter
 }
 
-type PackageUpdateList []events.PackageUpdate
-
-func (pkgsu PackageUpdateList) PackagesPath() []string {
-	pkgs := make([]string, len(pkgsu))
-	for i, pkg := range pkgsu {
-		pkgs[i] = pkg.Package
-	}
-	return pkgs
-}
-
-func (pkgsu PackageUpdateList) FilesPath() []string {
-	files := make([]string, 0)
-	for _, pkg := range pkgsu {
-		files = append(files, pkg.Files...)
-	}
-	return files
-}
-
 func NewPackageWatcher(logger log.Logger, emitter events.Emitter) (*PackageWatcher, error) {
 	watcher, err := fsnotify.NewWatcher()
 	if err != nil {
@@ -53,7 +36,7 @@ func NewPackageWatcher(logger log.Logger, emitter events.Emitter) (*PackageWatch
 
 	ctx, cancel := context.WithCancel(context.Background())
 	p := &PackageWatcher{
-		pkgs:    []string{},
+		pkgsDir: []string{},
 		logger:  logger,
 		watcher: watcher,
 		ctx:     ctx,
@@ -70,6 +53,10 @@ func (p *PackageWatcher) Stop() {
 	p.stop()
 }
 
+// AddPackages adds new packages to the watcher.
+// Packages are sorted by their length in descending order to facilitate easier
+// and more efficient matching with corresponding paths. The longest paths are
+// compared first.
 func (p *PackageWatcher) AddPackages(pkgs ...gnomod.Pkg) error {
 	for _, pkg := range pkgs {
 		dir := pkg.Dir
@@ -79,17 +66,17 @@ func (p *PackageWatcher) AddPackages(pkgs ...gnomod.Pkg) error {
 			return fmt.Errorf("unable to get absolute path of %q: %w", dir, err)
 		}
 
-		// Find the correct insertion point using sorting search
-		index := sort.Search(len(p.pkgs), func(i int) bool {
-			return len(p.pkgs[i]) <= len(dir)
+		// Use binary search to find the correct insertion point
+		index := sort.Search(len(p.pkgsDir), func(i int) bool {
+			return len(p.pkgsDir[i]) <= len(dir) // Longest paths first
 		})
 
-		// Check if the string already exists at the insertion point
-		if index < len(p.pkgs) && (p.pkgs)[index] == dir {
-			continue // Skip as it's a duplicate
+		// Check for duplicates at the insertion point to avoid redundancy
+		if index < len(p.pkgsDir) && p.pkgsDir[index] == dir {
+			continue // Skip
 		}
 
-		// Add the pakcage to the watcher
+		// Add the package to the watcher and handle any errors
 		if err := p.watcher.Add(abs); err != nil {
 			return fmt.Errorf("unable to watch %q: %w", pkg.Dir, err)
 		}
@@ -99,15 +86,14 @@ func (p *PackageWatcher) AddPackages(pkgs ...gnomod.Pkg) error {
 }
 
 func (p *PackageWatcher) startWatching() {
-	const timeout = time.Millisecond * 500
-
-	cerrs := make(chan error, 1)
+	const timeout = time.Millisecond * 500 // Debounce interval
 
-	cwatch := make(chan PackageUpdateList)
+	cErrors := make(chan error, 1)
+	cPkgUpdate := make(chan PackageUpdateList)
 
 	go func() {
-		defer close(cerrs)
-		defer close(cwatch)
+		defer close(cErrors)
+		defer close(cPkgUpdate)
 
 		var debounceTimer <-chan time.Time
 		var pathList = []string{}
@@ -120,50 +106,59 @@ func (p *PackageWatcher) startWatching() {
 			case watchErr := <-p.watcher.Errors:
 				err = fmt.Errorf("watch error: %w", watchErr)
 			case <-debounceTimer:
+				// Process and emit package updates after the debounce interval
 				updates := p.generatePackagesUpdateList(pathList)
 				for _, update := range updates {
 					p.logger.Error("packages update",
 						"pkg", update.Package,
 						"files", update.Files,
 					)
 				}
-				panic(fmt.Sprintf("%+v", updates))
-
-				cwatch <- updates
 
-				// Notify that we have some packages update
+				// Send updates
+				cPkgUpdate <- updates
 				p.emitter.Emit(events.NewPackagesUpdateEvent(updates))
 
-				// Reset pathList and debounceTimer
+				// Reset the path list and debounce timer
 				pathList = []string{}
 				debounceTimer = nil
 			case evt := <-p.watcher.Events:
+				// Only handle write operations
 				if evt.Op != fsnotify.Write {
 					continue
 				}
 
 				pathList = append(pathList, evt.Name)
+
+				// Set up the debounce timer
 				debounceTimer = time.After(timeout)
 			}
 		}
 
-		cerrs <- err
+		cErrors <- err // Send any final error to the channel
 	}()
 
-	p.PackagesUpdate = cwatch
-	p.Errors = cerrs
+	// Set update channels
+	p.PackagesUpdate = cPkgUpdate
+	p.Errors = cErrors
 }
 
 func (p *PackageWatcher) generatePackagesUpdateList(paths []string) PackageUpdateList {
 	pkgsUpdate := []events.PackageUpdate{}
 
-	mpkgs := map[string]*events.PackageUpdate{} // pkg -> update
+	mpkgs := map[string]*events.PackageUpdate{} // Pkg -> Update
 	for _, path := range paths {
-		for _, pkg := range p.pkgs {
+		for _, pkg := range p.pkgsDir {
+			// Check if the path is inside the package directory
 			if !strings.HasPrefix(pkg, path) {
 				continue
 			}
 
+			if len(pkg) == len(path) {
+				continue // Skip if pkg == path
+			}
+
+			// Accumulate file updates for each package
 			pkgu, ok := mpkgs[pkg]
 			if !ok {
 				pkgsUpdate = append(pkgsUpdate, events.PackageUpdate{
@@ -173,13 +168,27 @@ func (p *PackageWatcher) generatePackagesUpdateList(paths []string) PackageUpdat
 				pkgu = &pkgsUpdate[len(pkgsUpdate)-1]
 			}
 
-			if len(pkg) == len(path) {
-				continue
-			}
-
 			pkgu.Files = append(pkgu.Files, path)
 		}
 	}
 
 	return pkgsUpdate
 }
+
+type PackageUpdateList []events.PackageUpdate
+
+func (pkgsu PackageUpdateList) PackagesPath() []string {
+	pkgs := make([]string, len(pkgsu))
+	for i, pkg := range pkgsu {
+		pkgs[i] = pkg.Package
+	}
+	return pkgs
+}
+
+func (pkgsu PackageUpdateList) FilesPath() []string {
+	files := make([]string, 0)
+	for _, pkg := range pkgsu {
+		files = append(files, pkg.Files...)
+	}
+	return files
+}