package epoch

import (
	"reflect"
	"testing"

	"github.com/prysmaticlabs/go-bitfield"
	pb "github.com/prysmaticlabs/prysm/proto/beacon/p2p/v1"
	ethpb "github.com/prysmaticlabs/prysm/proto/eth/v1alpha1"
	"github.com/prysmaticlabs/prysm/shared/params"
)

func TestComputeValidatorParticipation(t *testing.T) {
	params.OverrideBeaconConfig(params.MinimalSpecConfig())
	epoch := uint64(1)
	attestedBalance := uint64(1)
	validatorCount := uint64(100)

	validators := make([]*ethpb.Validator, validatorCount)
	balances := make([]uint64, validatorCount)
	for i := 0; i < len(validators); i++ {
		validators[i] = &ethpb.Validator{
			ExitEpoch:        params.BeaconConfig().FarFutureEpoch,
			EffectiveBalance: params.BeaconConfig().MaxEffectiveBalance,
		}
		balances[i] = params.BeaconConfig().MaxEffectiveBalance
	}

	atts := []*pb.PendingAttestation{{Data: &ethpb.AttestationData{Crosslink: &ethpb.Crosslink{Shard: 0}, Target: &ethpb.Checkpoint{}}}}
	var crosslinks []*ethpb.Crosslink
	for i := uint64(0); i < params.BeaconConfig().ShardCount; i++ {
		crosslinks = append(crosslinks, &ethpb.Crosslink{
			StartEpoch: 0,
			DataRoot:   []byte{'A'},
		})
	}

	s := &pb.BeaconState{
		Slot:                       epoch*params.BeaconConfig().SlotsPerEpoch + 1,
		Validators:                 validators,
		Balances:                   balances,
		BlockRoots:                 make([][]byte, 128),
		Slashings:                  []uint64{0, 1e9, 1e9},
		RandaoMixes:                make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
		ActiveIndexRoots:           make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
		CompactCommitteesRoots:     make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
		CurrentCrosslinks:          crosslinks,
		CurrentEpochAttestations:   atts,
		FinalizedCheckpoint:        &ethpb.Checkpoint{},
		JustificationBits:          bitfield.Bitvector4{0x00},
		CurrentJustifiedCheckpoint: &ethpb.Checkpoint{},
	}

	res, err := ComputeValidatorParticipation(s)
	if err != nil {
		t.Fatal(err)
	}

	wanted := &ethpb.ValidatorParticipation{
		VotedEther:              attestedBalance,
		EligibleEther:           validatorCount * params.BeaconConfig().MaxEffectiveBalance,
		GlobalParticipationRate: float32(attestedBalance) / float32(validatorCount*params.BeaconConfig().MaxEffectiveBalance),
	}

	if !reflect.DeepEqual(res, wanted) {
		t.Errorf("Incorrect validator participation, wanted %v received %v", wanted, res)
	}
}