package gapi

import (
	"context"
	"database/sql"
	"testing"

	db "github.com/FernandoJVideira/simple_bank/internal/db/sqlc"
	"github.com/FernandoJVideira/simple_bank/internal/domain/role"
	"github.com/FernandoJVideira/simple_bank/internal/security"
	"github.com/FernandoJVideira/simple_bank/internal/service"
	mocksvc "github.com/FernandoJVideira/simple_bank/internal/service/mock"
	"github.com/FernandoJVideira/simple_bank/pb"
	"github.com/FernandoJVideira/simple_bank/pkg/testutil"
	"github.com/stretchr/testify/require"
	"go.uber.org/mock/gomock"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

func randomUser(t *testing.T) (user db.User, password string) {
	password = testutil.RandomString(6)
	hashedPassword, err := security.HashPassword(password)
	if err != nil {
		t.Fatal(err)
	}

	user = db.User{
		Username:       testutil.RandomOwner(),
		HashedPassword: hashedPassword,
		Role:           role.MemberRole,
		FullName:       testutil.RandomOwner(),
		Email:          testutil.RandomEmail(),
	}

	return
}

func TestCreateUserRPC(t *testing.T) {
	user, password := randomUser(t)

	testCases := []struct {
		name          string
		req           *pb.CreateUserRequest
		buildStubs    func(userService *mocksvc.MockUserService)
		checkResponse func(t *testing.T, res *pb.CreateUserResponse, err error)
	}{
		{
			name: "OK",
			req: &pb.CreateUserRequest{
				Username: user.Username,
				Password: password,
				FullName: user.FullName,
				Email:    user.Email,
			},
			buildStubs: func(userService *mocksvc.MockUserService) {
				arg := service.RegisterUserRequest{
					Username: user.Username,
					Password: password,
					FullName: user.FullName,
					Email:    user.Email,
				}

				userService.EXPECT().
					CreateUser(gomock.Any(), gomock.Eq(arg)).
					Times(1).
					Return(&service.RegisterUserResponse{
						User: user,
					}, nil)
			},
			checkResponse: func(t *testing.T, res *pb.CreateUserResponse, err error) {
				require.NoError(t, err)
				require.NotNil(t, res)
				require.Equal(t, user.Username, res.User.Username)
				require.Equal(t, user.FullName, res.User.FullName)
				require.Equal(t, user.Email, res.User.Email)
				require.NotEmpty(t, res.User.CreatedAt)
			},
		},
		{
			name: "InternalError",
			req: &pb.CreateUserRequest{
				Username: user.Username,
				Password: password,
				FullName: user.FullName,
				Email:    user.Email,
			},
			buildStubs: func(userService *mocksvc.MockUserService) {
				userService.EXPECT().
					CreateUser(gomock.Any(), gomock.Any()).
					Times(1).
					Return(nil, sql.ErrConnDone)
			},
			checkResponse: func(t *testing.T, res *pb.CreateUserResponse, err error) {
				require.Error(t, err)
				st, ok := status.FromError(err)
				require.True(t, ok)
				require.Equal(t, st.Code(), codes.Internal)
			},
		},
		{
			name: "DuplicateUsername",
			req: &pb.CreateUserRequest{
				Username: user.Username,
				Password: password,
				FullName: user.FullName,
				Email:    user.Email,
			},

			buildStubs: func(userService *mocksvc.MockUserService) {
				userService.EXPECT().
					CreateUser(gomock.Any(), gomock.Any()).
					Times(1).
					Return(nil, db.ErrUniqueViolation)
			},
			checkResponse: func(t *testing.T, res *pb.CreateUserResponse, err error) {
				require.Error(t, err)
				st, ok := status.FromError(err)
				require.True(t, ok)
				require.Equal(t, st.Code(), codes.AlreadyExists)
			},
		},
		{
			name: "InvalidEmail",
			req: &pb.CreateUserRequest{
				Username: user.Username,
				Password: password,
				FullName: user.FullName,
				Email:    "invalid-email",
			},
			buildStubs: func(userService *mocksvc.MockUserService) {
				userService.EXPECT().
					CreateUser(gomock.Any(), gomock.Any()).
					Times(0)
			},
			checkResponse: func(t *testing.T, res *pb.CreateUserResponse, err error) {
				require.Error(t, err)
				st, ok := status.FromError(err)
				require.True(t, ok)
				require.Equal(t, st.Code(), codes.InvalidArgument)
			},
		},
		{
			name: "PasswordTooShort",
			req: &pb.CreateUserRequest{
				Username: user.Username,
				Password: "short",
				FullName: user.FullName,
				Email:    user.Email,
			},
			buildStubs: func(userService *mocksvc.MockUserService) {
				userService.EXPECT().
					CreateUser(gomock.Any(), gomock.Any()).
					Times(0)
			},
			checkResponse: func(t *testing.T, res *pb.CreateUserResponse, err error) {
				require.Error(t, err)
				st, ok := status.FromError(err)
				require.True(t, ok)
				require.Equal(t, st.Code(), codes.InvalidArgument)
			},
		},
	}

	for i := range testCases {
		tc := testCases[i]
		t.Run(tc.name, func(t *testing.T) {
			userCtrl := gomock.NewController(t)
			defer userCtrl.Finish()

			userService := mocksvc.NewMockUserService(userCtrl)

			tc.buildStubs(userService)

			// Start test server and send request
			s := newTestServer(t, nil, nil, userService, nil)
			res, err := s.CreateUser(context.Background(), tc.req)

			tc.checkResponse(t, res, err)
		})
	}
}