package lease

import (
	"context"
	"errors"
	"testing"

	"github.com/superfly/ltx"
)

type fakeLister struct {
	levels map[int][]*ltx.FileInfo
	err    error
	asked  []int
}

func (f *fakeLister) LTXFiles(_ context.Context, level int, _ ltx.TXID, _ bool) (ltx.FileIterator, error) {
	f.asked = append(f.asked, level)
	if f.err != nil {
		return nil, f.err
	}
	return ltx.NewFileInfoSliceIterator(f.levels[level]), nil
}

func TestHasReplicaIn(t *testing.T) {
	ctx := context.Background()
	empty := &fakeLister{}
	if has, err := hasReplicaIn(ctx, empty); has || err != nil {
		t.Fatalf("empty = %v, %v", has, err)
	}
	if len(empty.asked) != 10 {
		t.Fatalf("levels asked = %v, want 0 to 9", empty.asked)
	}
	snap := &fakeLister{levels: map[int][]*ltx.FileInfo{9: {{Level: 9, MinTXID: 1, MaxTXID: 7, Size: 4096}}}}
	if has, err := hasReplicaIn(ctx, snap); !has || err != nil {
		t.Fatalf("a snapshot at level 9 = %v, %v", has, err)
	}
	broken := &fakeLister{err: errors.New("listing failed")}
	if has, err := hasReplicaIn(ctx, broken); has || err == nil {
		t.Fatalf("a failed listing = %v, %v; want an error, never false", has, err)
	}
}