1 files changed, 64 insertions, 0 deletions
diff --git a/internal/audio/validate_test.go b/internal/audio/validate_test.go
new file mode 100644
index 0000000..7bc3c9e
--- /dev/null
+++ b/internal/audio/validate_test.go
@@ -0,0 +1,64 @@
+package audio
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestValidateBulgarianText(t *testing.T) {
+	tests := []struct {
+		name    string
+		text    string
+		wantErr bool
+		errMsg  string
+	}{
+		{
+			name:    "valid Bulgarian word",
+			text:    "ябълка",
+			wantErr: false,
+		},
+		{
+			name:    "valid Bulgarian sentence",
+			text:    "Здравей, как си?",
+			wantErr: false,
+		},
+		{
+			name:    "empty text",
+			text:    "",
+			wantErr: true,
+			errMsg:  "text cannot be empty",
+		},
+		{
+			name:    "whitespace only",
+			text:    "   \t\n",
+			wantErr: true,
+			errMsg:  "text cannot be empty",
+		},
+		{
+			name:    "English text",
+			text:    "Hello world",
+			wantErr: true,
+			errMsg:  "text must contain Cyrillic characters",
+		},
+		{
+			name:    "numbers only",
+			text:    "12345",
+			wantErr: true,
+			errMsg:  "text must contain Cyrillic characters",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := ValidateBulgarianText(tt.text)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("ValidateBulgarianText() error = %v, wantErr %v", err, tt.wantErr)
+			}
+			if tt.wantErr && err != nil {
+				if !strings.Contains(err.Error(), tt.errMsg) {
+					t.Errorf("ValidateBulgarianText() error = %v, want error containing %v", err.Error(), tt.errMsg)
+				}
+			}
+		})
+	}
+}