Streaming with range requests and path safety, cover art discovery/resize cache

internal/coverart/coverart_test.go

@@ -0,0 +1,149 @@
+package coverart
+
+import (
+	"image"
+	"image/color"
+	"image/jpeg"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func writeTestJPEG(t *testing.T, path string, w, h int) {
+	t.Helper()
+	img := image.NewRGBA(image.Rect(0, 0, w, h))
+	for y := 0; y < h; y++ {
+		for x := 0; x < w; x++ {
+			img.Set(x, y, color.RGBA{R: uint8(x % 255), G: uint8(y % 255), B: 100, A: 255})
+		}
+	}
+	f, err := os.Create(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+	if err := jpeg.Encode(f, img, nil); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestFindFolderImagePriority(t *testing.T) {
+	dir := t.TempDir()
+	writeTestJPEG(t, filepath.Join(dir, "folder.jpg"), 4, 4)
+	writeTestJPEG(t, filepath.Join(dir, "cover.jpg"), 4, 4)
+
+	got := FindFolderImage(dir)
+	if filepath.Base(got) != "cover.jpg" {
+		t.Errorf("FindFolderImage = %q, want cover.jpg to take priority over folder.jpg", got)
+	}
+}
+
+func TestFindFolderImageNone(t *testing.T) {
+	dir := t.TempDir()
+	if got := FindFolderImage(dir); got != "" {
+		t.Errorf("FindFolderImage = %q, want empty when no cover exists", got)
+	}
+}
+
+func TestGetOrCreateResizesAndCaches(t *testing.T) {
+	dir := t.TempDir()
+	srcPath := filepath.Join(dir, "source.jpg")
+	writeTestJPEG(t, srcPath, 800, 600)
+
+	cacheDir := filepath.Join(dir, "cache")
+	store := New(cacheDir, "")
+
+	path1, err := store.GetOrCreate(srcPath, "hash1", 200)
+	if err != nil {
+		t.Fatalf("GetOrCreate: %v", err)
+	}
+	info1, err := os.Stat(path1)
+	if err != nil {
+		t.Fatalf("stat cached file: %v", err)
+	}
+
+	f, err := os.Open(path1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cfg, _, err := image.DecodeConfig(f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("decoding resized image: %v", err)
+	}
+	if cfg.Width != 200 {
+		t.Errorf("resized width = %d, want 200", cfg.Width)
+	}
+	if cfg.Height >= 600 {
+		t.Errorf("resized height = %d, should be scaled down proportionally", cfg.Height)
+	}
+
+	// Second call should hit the cache: same path, same mtime (not regenerated).
+	path2, err := store.GetOrCreate(srcPath, "hash1", 200)
+	if err != nil {
+		t.Fatalf("GetOrCreate (2nd): %v", err)
+	}
+	if path1 != path2 {
+		t.Errorf("cached path changed: %q -> %q", path1, path2)
+	}
+	info2, err := os.Stat(path2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !info1.ModTime().Equal(info2.ModTime()) {
+		t.Error("second GetOrCreate call regenerated the cached file instead of reusing it")
+	}
+}
+
+func TestGetOrCreateSmallImageNotUpscaled(t *testing.T) {
+	dir := t.TempDir()
+	srcPath := filepath.Join(dir, "small.jpg")
+	writeTestJPEG(t, srcPath, 50, 50)
+
+	store := New(filepath.Join(dir, "cache"), "")
+	path, err := store.GetOrCreate(srcPath, "hash-small", 500)
+	if err != nil {
+		t.Fatalf("GetOrCreate: %v", err)
+	}
+	f, err := os.Open(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+	cfg, _, err := image.DecodeConfig(f)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.Width != 50 || cfg.Height != 50 {
+		t.Errorf("size = %dx%d, want unscaled 50x50", cfg.Width, cfg.Height)
+	}
+}
+
+func TestGetOrCreateRejectsOversizedSource(t *testing.T) {
+	dir := t.TempDir()
+	srcPath := filepath.Join(dir, "big.jpg")
+	writeTestJPEG(t, srcPath, 200, 200)
+
+	info, err := os.Stat(srcPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	store := New(filepath.Join(dir, "cache"), "")
+	store.MaxSourceBytes = info.Size() - 1 // just under the real file size
+
+	if _, err := store.GetOrCreate(srcPath, "hash-big", 50); err == nil {
+		t.Fatal("expected GetOrCreate to reject a source image over MaxSourceBytes")
+	}
+}
+
+func TestGetOrCreateAllowsUnderLimit(t *testing.T) {
+	dir := t.TempDir()
+	srcPath := filepath.Join(dir, "ok.jpg")
+	writeTestJPEG(t, srcPath, 10, 10)
+
+	store := New(filepath.Join(dir, "cache"), "")
+	if _, err := store.GetOrCreate(srcPath, "hash-ok", 5); err != nil {
+		t.Fatalf("GetOrCreate should succeed under the default limit: %v", err)
+	}
+}