fix: Wails file drop, duplicate listeners, trim drag, crop stage, preview cache/pixfmt, NSIS temp quoting

internal/preview/server_test.go

@@ -3,6 +3,7 @@ package preview
 import (
 	"io"
 	"net/http"
+	"os"
 	"os/exec"
 	"path/filepath"
 	"testing"
@@ -85,3 +86,57 @@ func TestPreviewServer_RangeThumbAndProxy(t *testing.T) {
 		t.Fatalf("expected 404, got %d", nfResp.StatusCode)
 	}
 }
+
+func TestPreviewServer_CacheInvalidationAndOddWidthProxy(t *testing.T) {
+	bins := media.FindBinaries("", "")
+	if bins.FFmpeg == "" || bins.FFprobe == "" {
+		t.Skip("ffmpeg/ffprobe not installed")
+	}
+
+	tmpDir := t.TempDir()
+	src := filepath.Join(tmpDir, "odd.mkv")
+	// Odd width (321x180) vp8 source forces libx264 transcode in /proxy
+	gen := exec.Command(bins.FFmpeg,
+		"-hide_banner", "-loglevel", "error",
+		"-f", "lavfi", "-i", "testsrc=duration=1:size=321x180:rate=30",
+		"-c:v", "libvpx", "-y", src,
+	)
+	if out, err := gen.CombinedOutput(); err != nil {
+		t.Fatalf("failed generating odd-width mkv: %v (%s)", err, string(out))
+	}
+
+	info, err := media.Probe(bins.FFprobe, src)
+	if err != nil {
+		t.Fatalf("probe failed: %v", err)
+	}
+
+	srv, err := Start(bins.FFmpeg)
+	if err != nil {
+		t.Fatalf("start failed: %v", err)
+	}
+	defer srv.Close()
+
+	id1 := srv.Register(info)
+
+	// /proxy must succeed even on odd width (321 -> 320)
+	pResp, err := http.Get(srv.BaseURL() + "/proxy?id=" + id1 + "&merge=0")
+	if err != nil {
+		t.Fatalf("GET /proxy failed: %v", err)
+	}
+	pBody, _ := io.ReadAll(pResp.Body)
+	pResp.Body.Close()
+	if pResp.StatusCode != http.StatusOK || len(pBody) < 500 {
+		t.Fatalf("expected valid MP4 proxy for odd-width source, status=%d len=%d", pResp.StatusCode, len(pBody))
+	}
+
+	// Overwrite same path with different size -> Register must yield a new ID
+	if err := os.WriteFile(src, []byte("different-content-size"), 0o644); err != nil {
+		t.Fatalf("overwrite failed: %v", err)
+	}
+	info2 := *info
+	info2.SizeBytes = 22
+	id2 := srv.Register(&info2)
+	if id1 == id2 {
+		t.Fatalf("expected different videoId after file modification at same path, both were %q", id1)
+	}
+}