1 files changed, 85 insertions, 0 deletions
diff --git a/internal/stats/stats_test.go b/internal/stats/stats_test.go
new file mode 100644
index 0000000..a81e215
--- /dev/null
+++ b/internal/stats/stats_test.go
@@ -0,0 +1,85 @@
+package stats
+
+import (
+	"context"
+	"path/filepath"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestUpdateAndSnapshot_Single(t *testing.T) {
+	t.Setenv("XDG_CACHE_HOME", t.TempDir())
+	SetWindow(2 * time.Minute)
+	if err := Update(context.Background(), "prov", "model", 10, 20); err != nil {
+		t.Fatalf("update: %v", err)
+	}
+	snap, err := TakeSnapshot()
+	if err != nil {
+		t.Fatalf("snapshot: %v", err)
+	}
+	if snap.Global.Reqs != 1 || snap.Global.Sent != 10 || snap.Global.Recv != 20 {
+		t.Fatalf("unexpected snap: %+v", snap)
+	}
+	if snap.Providers["prov"].Totals.Reqs != 1 || snap.Providers["prov"].Models["model"].Reqs != 1 {
+		t.Fatalf("missing provider/model aggregates: %+v", snap)
+	}
+}
+
+func TestUpdate_PrunesOld_ByWindow(t *testing.T) {
+	t.Setenv("XDG_CACHE_HOME", t.TempDir())
+	SetWindow(2 * time.Second)
+	ctx := context.Background()
+	if err := Update(ctx, "p", "m", 1, 1); err != nil {
+		t.Fatal(err)
+	}
+	time.Sleep(2200 * time.Millisecond)
+	if err := Update(ctx, "p", "m", 2, 2); err != nil {
+		t.Fatal(err)
+	}
+	snap, err := TakeSnapshot()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if snap.Global.Reqs != 1 || snap.Global.Sent != 2 || snap.Global.Recv != 2 {
+		t.Fatalf("expected first event pruned, got %+v", snap)
+	}
+}
+
+func TestConcurrentUpdates_LockSafety(t *testing.T) {
+	t.Setenv("XDG_CACHE_HOME", t.TempDir())
+	SetWindow(1 * time.Minute)
+	ctx := context.Background()
+	var wg sync.WaitGroup
+	n := 20
+	for i := 0; i < n; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			if err := Update(ctx, "p", "m", i, i); err != nil {
+				t.Errorf("update %d: %v", i, err)
+			}
+		}(i)
+	}
+	wg.Wait()
+	snap, err := TakeSnapshot()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if snap.Global.Reqs != int64(n) {
+		t.Fatalf("reqs mismatch: %d", snap.Global.Reqs)
+	}
+}
+
+func TestCacheDir_XDG(t *testing.T) {
+	dir := t.TempDir()
+	t.Setenv("XDG_CACHE_HOME", dir)
+	got, err := CacheDir()
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := filepath.Join(dir, "hexai")
+	if got != want {
+		t.Fatalf("got %q want %q", got, want)
+	}
+}