package etcdserver

import (
	"context"
	"strings"
	"sync"
	"testing"

	"github.com/stretchr/testify/assert"
	"go.uber.org/zap"

	pb "go.etcd.io/etcd/api/v3/etcdserverpb"
	"go.etcd.io/etcd/server/v3/lease"
	"go.etcd.io/etcd/server/v3/mvcc"
	betesting "go.etcd.io/etcd/server/v3/mvcc/backend/testing"
)

func TestReadonlyTxnError(t *testing.T) {
	b, _ := betesting.NewDefaultTmpBackend(t)
	defer betesting.Close(t, b)
	s := mvcc.New(zap.NewExample(), b, &lease.FakeLessor{}, mvcc.StoreConfig{})
	defer s.Close()

	// setup minimal server to get access to applier
	srv := &EtcdServer{lgMu: new(sync.RWMutex), lg: zap.NewExample(), r: *newRaftNode(raftNodeConfig{lg: zap.NewExample(), Node: newNodeRecorder()})}
	srv.kv = s
	srv.be = b

	a := srv.newApplierV3Backend()

	// setup cancelled context
	ctx, cancel := context.WithCancel(context.TODO())
	cancel()

	// put some data to prevent early termination in rangeKeys
	// we are expecting failure on cancelled context check
	s.Put([]byte("foo"), []byte("bar"), lease.NoLease)

	txn := &pb.TxnRequest{
		Success: []*pb.RequestOp{
			{
				Request: &pb.RequestOp_RequestRange{
					RequestRange: &pb.RangeRequest{
						Key: []byte("foo"),
					},
				},
			},
		},
	}

	_, _, err := a.Txn(ctx, txn)
	if err == nil || !strings.Contains(err.Error(), "applyTxn: failed Range: rangeKeys: context cancelled: context canceled") {
		t.Fatalf("Expected context canceled error, got %v", err)
	}
}

func TestWriteTxnPanic(t *testing.T) {
	b, _ := betesting.NewDefaultTmpBackend(t)
	defer betesting.Close(t, b)
	s := mvcc.New(zap.NewExample(), b, &lease.FakeLessor{}, mvcc.StoreConfig{})
	defer s.Close()

	// setup minimal server to get access to applier
	srv := &EtcdServer{lgMu: new(sync.RWMutex), lg: zap.NewExample(), r: *newRaftNode(raftNodeConfig{lg: zap.NewExample(), Node: newNodeRecorder()})}
	srv.kv = s
	srv.be = b

	a := srv.newApplierV3Backend()

	// setup cancelled context
	ctx, cancel := context.WithCancel(context.TODO())
	cancel()

	// write txn that puts some data and then fails in range due to cancelled context
	txn := &pb.TxnRequest{
		Success: []*pb.RequestOp{
			{
				Request: &pb.RequestOp_RequestPut{
					RequestPut: &pb.PutRequest{
						Key:   []byte("foo"),
						Value: []byte("bar"),
					},
				},
			},
			{
				Request: &pb.RequestOp_RequestRange{
					RequestRange: &pb.RangeRequest{
						Key: []byte("foo"),
					},
				},
			},
		},
	}

	assert.Panics(t, func() { a.Txn(ctx, txn) }, "Expected panic in Txn with writes")
}