package example

import (
	"context"
	"fmt"
	"math/rand"
	"net"
	"os"
	"testing"
	"time"

	"github.com/stretchr/testify/require"

	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"

	"github.com/tendermint/tendermint/libs/log"
	tmnet "github.com/tendermint/tendermint/libs/net"

	abciclient "github.com/tendermint/tendermint/abci/client"
	"github.com/tendermint/tendermint/abci/example/code"
	"github.com/tendermint/tendermint/abci/example/kvstore"
	abciserver "github.com/tendermint/tendermint/abci/server"
	"github.com/tendermint/tendermint/abci/types"
)

func init() {
	rand.Seed(time.Now().UnixNano())
}

func TestKVStore(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	logger := log.NewNopLogger()

	t.Log("### Testing KVStore")
	testBulk(ctx, t, logger, kvstore.NewApplication())
}

func TestBaseApp(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	logger := log.NewNopLogger()

	t.Log("### Testing BaseApp")
	testBulk(ctx, t, logger, types.NewBaseApplication())
}

func TestGRPC(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	logger := log.NewNopLogger()

	t.Log("### Testing GRPC")
	testGRPCSync(ctx, t, logger, types.NewGRPCApplication(types.NewBaseApplication()))
}

func testBulk(ctx context.Context, t *testing.T, logger log.Logger, app types.Application) {
	t.Helper()

	const numDeliverTxs = 700000
	socketFile := fmt.Sprintf("test-%08x.sock", rand.Int31n(1<<30))
	defer os.Remove(socketFile)
	socket := fmt.Sprintf("unix://%v", socketFile)
	// Start the listener
	server := abciserver.NewSocketServer(logger.With("module", "abci-server"), socket, app)
	t.Cleanup(server.Wait)
	err := server.Start(ctx)
	require.NoError(t, err)

	// Connect to the socket
	client := abciclient.NewSocketClient(logger.With("module", "abci-client"), socket, false)
	t.Cleanup(client.Wait)

	err = client.Start(ctx)
	require.NoError(t, err)

	// Construct request
	rfb := types.RequestFinalizeBlock{Txs: make([][]byte, numDeliverTxs)}
	for counter := 0; counter < numDeliverTxs; counter++ {
		rfb.Txs[counter] = []byte("test")
	}
	// Send bulk request
	res, err := client.FinalizeBlock(ctx, rfb)
	require.NoError(t, err)
	require.Equal(t, numDeliverTxs, len(res.Txs), "Number of txs doesn't match")
	for _, tx := range res.Txs {
		require.Equal(t, tx.Code, code.CodeTypeOK, "Tx failed")
	}

	// Send final flush message
	err = client.Flush(ctx)
	require.NoError(t, err)
}

//-------------------------
// test grpc

func dialerFunc(ctx context.Context, addr string) (net.Conn, error) {
	return tmnet.Connect(addr)
}

func testGRPCSync(ctx context.Context, t *testing.T, logger log.Logger, app types.ABCIApplicationServer) {
	t.Helper()
	numDeliverTxs := 680000
	socketFile := fmt.Sprintf("/tmp/test-%08x.sock", rand.Int31n(1<<30))
	defer os.Remove(socketFile)
	socket := fmt.Sprintf("unix://%v", socketFile)

	// Start the listener
	server := abciserver.NewGRPCServer(logger.With("module", "abci-server"), socket, app)

	require.NoError(t, server.Start(ctx))
	t.Cleanup(server.Wait)

	// Connect to the socket
	conn, err := grpc.Dial(socket,
		grpc.WithTransportCredentials(insecure.NewCredentials()),
		grpc.WithContextDialer(dialerFunc),
	)
	require.NoError(t, err, "Error dialing GRPC server")

	t.Cleanup(func() {
		if err := conn.Close(); err != nil {
			t.Error(err)
		}
	})

	client := types.NewABCIApplicationClient(conn)

	// Construct request
	rfb := types.RequestFinalizeBlock{Txs: make([][]byte, numDeliverTxs)}
	for counter := 0; counter < numDeliverTxs; counter++ {
		rfb.Txs[counter] = []byte("test")
	}

	// Send request
	response, err := client.FinalizeBlock(ctx, &rfb)
	require.NoError(t, err, "Error in GRPC FinalizeBlock")
	require.Equal(t, numDeliverTxs, len(response.Txs), "Number of txs returned via GRPC doesn't match")
	for _, tx := range response.Txs {
		require.Equal(t, tx.Code, code.CodeTypeOK, "Tx failed")
	}
}