package testing

import (
	"context"
	"errors"

	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
)

var (
	errInvalidDiff    = errors.New("invalid diff")
	errNetmapNotFound = errors.New("netmap not found")
)

type TestNetmapSource struct {
	Netmaps      map[uint64]*netmap.NetMap
	CurrentEpoch uint64
}

func (s *TestNetmapSource) GetNetMap(ctx context.Context, diff uint64) (*netmap.NetMap, error) {
	if diff >= s.CurrentEpoch {
		return nil, errInvalidDiff
	}
	return s.GetNetMapByEpoch(ctx, s.CurrentEpoch-diff)
}

func (s *TestNetmapSource) GetNetMapByEpoch(_ context.Context, epoch uint64) (*netmap.NetMap, error) {
	if nm, found := s.Netmaps[epoch]; found {
		return nm, nil
	}
	return nil, errNetmapNotFound
}

func (s *TestNetmapSource) Epoch(context.Context) (uint64, error) {
	return s.CurrentEpoch, nil
}