package rpc

import (
	"context"
	"errors"
	"testing"
	"time"

	"github.com/prysmaticlabs/prysm/shared/event"

	ptypes "github.com/gogo/protobuf/types"
	"github.com/golang/mock/gomock"
	"github.com/prysmaticlabs/prysm/beacon-chain/internal"
	pbp2p "github.com/prysmaticlabs/prysm/proto/beacon/p2p/v1"
	pb "github.com/prysmaticlabs/prysm/proto/beacon/rpc/v1"
	"github.com/prysmaticlabs/prysm/shared/testutil"
	logTest "github.com/sirupsen/logrus/hooks/test"
)

type faultyPOWChainService struct {
	chainStartFeed *event.Feed
}

func (f *faultyPOWChainService) HasChainStartLogOccurred() (bool, uint64, error) {
	return false, uint64(time.Now().Unix()), nil
}
func (f *faultyPOWChainService) ChainStartFeed() *event.Feed {
	return f.chainStartFeed
}

type mockPOWChainService struct {
	chainStartFeed *event.Feed
}

func (m *mockPOWChainService) HasChainStartLogOccurred() (bool, uint64, error) {
	return true, uint64(time.Unix(0, 0).Unix()), nil
}
func (m *mockPOWChainService) ChainStartFeed() *event.Feed {
	return m.chainStartFeed
}

func TestWaitForChainStart_ContextClosed(t *testing.T) {
	hook := logTest.NewGlobal()
	ctx, cancel := context.WithCancel(context.Background())
	beaconServer := &BeaconServer{
		ctx: ctx,
		powChainService: &faultyPOWChainService{
			chainStartFeed: new(event.Feed),
		},
	}
	exitRoutine := make(chan bool)
	ctrl := gomock.NewController(t)
	defer ctrl.Finish()
	mockStream := internal.NewMockBeaconService_WaitForChainStartServer(ctrl)
	go func(tt *testing.T) {
		if err := beaconServer.WaitForChainStart(&ptypes.Empty{}, mockStream); err != nil {
			tt.Errorf("Could not call RPC method: %v", err)
		}
		<-exitRoutine
	}(t)
	cancel()
	exitRoutine <- true
	testutil.AssertLogsContain(t, hook, "RPC context closed, exiting goroutine")
}

func TestWaitForChainStart_AlreadyStarted(t *testing.T) {
	beaconServer := &BeaconServer{
		ctx: context.Background(),
		powChainService: &mockPOWChainService{
			chainStartFeed: new(event.Feed),
		},
	}
	ctrl := gomock.NewController(t)
	defer ctrl.Finish()
	mockStream := internal.NewMockBeaconService_WaitForChainStartServer(ctrl)
	mockStream.EXPECT().Send(
		&pb.ChainStartResponse{
			Started:     true,
			GenesisTime: uint64(time.Unix(0, 0).Unix()),
		},
	).Return(nil)
	if err := beaconServer.WaitForChainStart(&ptypes.Empty{}, mockStream); err != nil {
		t.Errorf("Could not call RPC method: %v", err)
	}
}

func TestWaitForChainStart_NotStartedThenLogFired(t *testing.T) {
	hook := logTest.NewGlobal()
	beaconServer := &BeaconServer{
		ctx:            context.Background(),
		chainStartChan: make(chan time.Time, 1),
		powChainService: &faultyPOWChainService{
			chainStartFeed: new(event.Feed),
		},
	}
	exitRoutine := make(chan bool)
	ctrl := gomock.NewController(t)
	defer ctrl.Finish()
	mockStream := internal.NewMockBeaconService_WaitForChainStartServer(ctrl)
	mockStream.EXPECT().Send(
		&pb.ChainStartResponse{
			Started:     true,
			GenesisTime: uint64(time.Unix(0, 0).Unix()),
		},
	).Return(nil)
	go func(tt *testing.T) {
		if err := beaconServer.WaitForChainStart(&ptypes.Empty{}, mockStream); err != nil {
			tt.Errorf("Could not call RPC method: %v", err)
		}
		<-exitRoutine
	}(t)
	beaconServer.chainStartChan <- time.Unix(0, 0)
	exitRoutine <- true
	testutil.AssertLogsContain(t, hook, "Sending ChainStart log and genesis time to connected validator clients")
}

func TestLatestAttestation_ContextClosed(t *testing.T) {
	hook := logTest.NewGlobal()
	mockOperationService := &mockOperationService{}
	ctx, cancel := context.WithCancel(context.Background())
	beaconServer := &BeaconServer{
		ctx:              ctx,
		operationService: mockOperationService,
	}
	exitRoutine := make(chan bool)
	ctrl := gomock.NewController(t)
	defer ctrl.Finish()
	mockStream := internal.NewMockBeaconService_LatestAttestationServer(ctrl)
	go func(tt *testing.T) {
		if err := beaconServer.LatestAttestation(&ptypes.Empty{}, mockStream); err != nil {
			tt.Errorf("Could not call RPC method: %v", err)
		}
		<-exitRoutine
	}(t)
	cancel()
	exitRoutine <- true
	testutil.AssertLogsContain(t, hook, "RPC context closed, exiting goroutine")
}

func TestLatestAttestation_FaultyServer(t *testing.T) {
	mockOperationService := &mockOperationService{}
	ctx, cancel := context.WithCancel(context.Background())
	beaconServer := &BeaconServer{
		ctx:                 ctx,
		operationService:    mockOperationService,
		incomingAttestation: make(chan *pbp2p.Attestation, 0),
	}
	ctrl := gomock.NewController(t)
	defer ctrl.Finish()

	exitRoutine := make(chan bool)
	attestation := &pbp2p.Attestation{}

	mockStream := internal.NewMockBeaconService_LatestAttestationServer(ctrl)
	mockStream.EXPECT().Send(attestation).Return(errors.New("something wrong"))
	// Tests a faulty stream.
	go func(tt *testing.T) {
		if err := beaconServer.LatestAttestation(&ptypes.Empty{}, mockStream); err.Error() != "something wrong" {
			tt.Errorf("Faulty stream should throw correct error, wanted 'something wrong', got %v", err)
		}
		<-exitRoutine
	}(t)

	beaconServer.incomingAttestation <- attestation
	cancel()
	exitRoutine <- true
}

func TestLatestAttestation_SendsCorrectly(t *testing.T) {
	hook := logTest.NewGlobal()
	operationService := &mockOperationService{}
	ctx, cancel := context.WithCancel(context.Background())
	beaconServer := &BeaconServer{
		ctx:                 ctx,
		operationService:    operationService,
		incomingAttestation: make(chan *pbp2p.Attestation, 0),
	}
	ctrl := gomock.NewController(t)
	defer ctrl.Finish()

	exitRoutine := make(chan bool)
	attestation := &pbp2p.Attestation{}
	mockStream := internal.NewMockBeaconService_LatestAttestationServer(ctrl)
	mockStream.EXPECT().Send(attestation).Return(nil)
	// Tests a good stream.
	go func(tt *testing.T) {
		if err := beaconServer.LatestAttestation(&ptypes.Empty{}, mockStream); err != nil {
			tt.Errorf("Could not call RPC method: %v", err)
		}
		<-exitRoutine
	}(t)
	beaconServer.incomingAttestation <- attestation
	cancel()
	exitRoutine <- true

	testutil.AssertLogsContain(t, hook, "Sending attestation to RPC clients")
}