Fix directory navigation and path initialization

- Initialize browser path to the actual startup directory instead of '/'
- Improve '..' navigation to be relative to the filesystem root
- Fix path duplication issues by avoiding redundant absolute path joining

cmd/pad/main.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"log"
 	"os"
+	"path/filepath"
 	"sync"
 
 	"gioui.org/app"
@@ -40,10 +41,18 @@ func run(w *app.Window) error {
 	rootDir := flag.String("root", startpath, "root directory for the filesystem")
 	flag.Parse()
 
-	fs := real.NewRealFileSystem(*rootDir)
-	log.Printf("using filesystem at %s", fs.WorkingDir)
+	// Initialize the real filesystem rooted at the system root "/"
+	// so that the browser can navigate the entire system.
+	fs := real.NewRealFileSystem("/")
 	
-	logic := editor.NewLogic(fs)
+	// Get the absolute path of the startup directory
+	startAbs, err := filepath.Abs(*rootDir)
+	if err != nil {
+		startAbs = *rootDir
+	}
+	log.Printf("using filesystem at / (startup directory: %s)", startAbs)
+
+	logic := editor.NewLogic(fs, startAbs)
 	renderer := ui.New(ui.Theme{FontSize: 14}, shaper, logic.State())
 	var mu sync.Mutex
 	var elems []ui.Element

internal/browser/handlers.go

@@ -3,8 +3,6 @@ package browser
 import (
 	"fmt"
 	"path/filepath"
-	"strings"
-
 	"pad/internal/ui"
 )
 
@@ -81,11 +79,24 @@ func HandleBrowserTap(bm *BrowserManager, s *BrowserState, index int) {
 		// Navigate into directory or up
 		var newPath string
 		if entry.Name == ".." {
-			newPath = filepath.Dir(s.CurrentPath)
+			// If we are at the root (".") stay there
+			if s.CurrentPath == "." || s.CurrentPath == "" {
+				newPath = "."
+			} else {
+				// Get parent directory
+				parent := filepath.Dir(s.CurrentPath)
+				if parent == "." || parent == "/" {
+					newPath = "."
+				} else {
+					newPath = parent
+				}
+			}
 		} else {
-			newPath = filepath.Join(s.CurrentPath, entry.Name)
-			if !strings.HasPrefix(newPath, "/") {
-				newPath = "/" + newPath
+			// Join child entry name
+			if s.CurrentPath == "." {
+				newPath = entry.Name
+			} else {
+				newPath = filepath.Join(s.CurrentPath, entry.Name)
 			}
 		}
 		bm.NavigateTo(newPath)

internal/browser/manager.go

@@ -26,7 +26,8 @@ func NewBrowserManager(state *BrowserState, wp *pool.WorkerPool, fs pool.FileSys
 }
 
 func (bm *BrowserManager) NavigateTo(dirPath string) {
-	fmt.Printf("NavigateTo: %s\n", dirPath)
+	fmt.Printf("NavigateTo: dirPath=%s, state.CurrentPath=%s\n", dirPath, bm.state.CurrentPath)
+	
 	bm.state.CurrentPath = dirPath
 	navigateToDirectory(bm.state, dirPath)
 	bm.state.Loading = true
@@ -86,7 +87,6 @@ func (bm *BrowserManager) HandleResult(result pool.Result) {
 }
 
 func (bm *BrowserManager) handleBuildIndexSuccess(result pool.Result) {
-	fmt.Printf("handleBuildIndexSuccess: TotalEntries=%d\n", len(result.Data.([]types.DirEntry)))
 	bm.state.Loading = false
 
 	// In the mock implementation, BuildIndexTask returns []types.DirEntry.
@@ -95,7 +95,9 @@ func (bm *BrowserManager) handleBuildIndexSuccess(result pool.Result) {
 	
 	var browserEntries []Entry
 	// Add ".." entry if not at root
-	if bm.state.CurrentPath != "/" && bm.state.CurrentPath != "." {
+	// We check against "/" specifically. "." is just a relative path for current dir, 
+	// which still has a parent.
+	if bm.state.CurrentPath != "/" && bm.state.CurrentPath != "" {
 		browserEntries = append(browserEntries, Entry{
 			Path:    filepath.Dir(bm.state.CurrentPath),
 			Name:    "..",
@@ -107,6 +109,7 @@ func (bm *BrowserManager) handleBuildIndexSuccess(result pool.Result) {
 	
 	for _, e := range entries {
 		info, _ := e.Info()
+		fmt.Printf("Adding entry: %s\n", e.Name())
 		browserEntries = append(browserEntries, Entry{
 			Path:    filepath.Join(bm.state.CurrentPath, e.Name()),
 			Name:    e.Name(),

internal/editor/logic.go

@@ -66,7 +66,7 @@ type Logic struct {
 }
 
 // NewLogic creates a new Logic instance, accepting an optional mockFS.
-func NewLogic(mfs pool.FileSystem) *Logic {
+func NewLogic(mfs pool.FileSystem, startPath ...string) *Logic {
 	state := NewState()
 	TheState = state
 
@@ -81,8 +81,12 @@ func NewLogic(mfs pool.FileSystem) *Logic {
 	wp := pool.NewWorkerPool(4)
 	wp.Start()
 
-	// Set browser initial path to mock root
-	state.Browser.CurrentPath = "/"
+	// Set browser initial path
+	path := "/"
+	if len(startPath) > 0 {
+		path = startPath[0]
+	}
+	state.Browser.CurrentPath = path
 	bm, _ := browser.NewBrowserManager(&state.Browser, wp, mockFS)
 
 	TheLogic = &Logic{