//go:build !windows

package disk

import (
	"io"
	"os"
	"testing"

	"golang.org/x/sys/unix"

	"s1d3sw1ped/steamcache2/steamcache/metrics"
)

func TestIsNoSpaceError(t *testing.T) {
	t.Parallel()
	if isNoSpaceError(nil) {
		t.Error("nil must not be ENOSPC")
	}
	if isNoSpaceError(io.EOF) {
		t.Error("EOF must not be ENOSPC")
	}
	if !isNoSpaceError(unix.ENOSPC) {
		t.Error("unix.ENOSPC should match")
	}
	wrapped := &os.PathError{Op: "write", Path: "x", Err: unix.ENOSPC}
	if !isNoSpaceError(wrapped) {
		t.Error("PathError wrapping ENOSPC should match")
	}
}

func TestDiskFS_ENOSPCCapacityPressure(t *testing.T) {
	t.Parallel()
	d, err := New(t.TempDir(), 1024, nil)
	if err != nil {
		t.Fatal(err)
	}
	met := metrics.NewMetrics()
	d.SetMetrics(met)

	d.recordIfNoSpace(io.EOF)
	if got := met.GetStats().CapacityPressureEvents; got != 0 {
		t.Fatalf("non-ENOSPC counted: %d", got)
	}

	d.recordIfNoSpace(unix.ENOSPC)
	if got := met.GetStats().CapacityPressureEvents; got != 1 {
		t.Fatalf("unix.ENOSPC: CapacityPressureEvents=%d, want 1", got)
	}
	if got := met.GetStats().Evictions; got != 0 {
		t.Fatalf("ENOSPC must not increment evictions, got %d", got)
	}

	d.recordIfNoSpace(&os.PathError{Op: "write", Path: "p", Err: unix.ENOSPC})
	if got := met.GetStats().CapacityPressureEvents; got != 2 {
		t.Fatalf("wrapped ENOSPC: CapacityPressureEvents=%d, want 2", got)
	}
}