// vfs/gc/gc_test.go
package gc

import (
	"errors"
	"fmt"
	"s1d3sw1ped/SteamCache2/vfs/memory"
	"s1d3sw1ped/SteamCache2/vfs/vfserror"
	"testing"
)

func TestGCOnFull(t *testing.T) {
	m := memory.New(10)
	gc := New(m, 2, LRUGC)

	for i := 0; i < 5; i++ {
		w, err := gc.Create(fmt.Sprintf("key%d", i), 2)
		if err != nil {
			t.Fatalf("Create failed: %v", err)
		}
		w.Write([]byte("ab"))
		w.Close()
	}

	// Cache full at 10 bytes
	w, err := gc.Create("key5", 2)
	if err != nil {
		t.Fatalf("Create failed: %v", err)
	}
	w.Write([]byte("cd"))
	w.Close()

	if gc.Size() > 10 {
		t.Errorf("Size exceeded: %d > 10", gc.Size())
	}

	// Check if older keys were evicted
	_, err = m.Open("key0")
	if err == nil {
		t.Error("Expected key0 to be evicted")
	}
}

func TestNoGCNeeded(t *testing.T) {
	m := memory.New(20)
	gc := New(m, 2, LRUGC)

	for i := 0; i < 5; i++ {
		w, err := gc.Create(fmt.Sprintf("key%d", i), 2)
		if err != nil {
			t.Fatalf("Create failed: %v", err)
		}
		w.Write([]byte("ab"))
		w.Close()
	}

	if gc.Size() != 10 {
		t.Errorf("Size: got %d, want 10", gc.Size())
	}
}

func TestGCInsufficientSpace(t *testing.T) {
	m := memory.New(5)
	gc := New(m, 1, LRUGC)

	w, err := gc.Create("key0", 10)
	if err == nil {
		w.Close()
		t.Error("Expected ErrDiskFull")
	} else if !errors.Is(err, vfserror.ErrDiskFull) {
		t.Errorf("Unexpected error: %v", err)
	}
}