package services

import (
	"context"
	"errors"
	"testing"

	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer"
	grpcService "git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/frostfs/services/tree"
	"github.com/stretchr/testify/require"
	"go.uber.org/zap/zaptest"
)

type treeClientMock struct {
	address string
	err     bool
}

func (t *treeClientMock) TreeClient(context.Context) (grpcService.TreeServiceClient, error) {
	if t.err {
		return nil, errors.New("error")
	}
	return nil, nil
}

func (t *treeClientMock) Address() string {
	return t.address
}

func TestHandleError(t *testing.T) {
	defaultError := errors.New("default error")
	for _, tc := range []struct {
		err           error
		expectedError error
	}{
		{
			err:           defaultError,
			expectedError: defaultError,
		},
		{
			err:           errors.New("something not found"),
			expectedError: layer.ErrNodeNotFound,
		},
		{
			err:           errors.New("something is denied by some acl rule"),
			expectedError: layer.ErrNodeAccessDenied,
		},
	} {
		t.Run("", func(t *testing.T) {
			err := handleError("err message", tc.err)
			require.True(t, errors.Is(err, tc.expectedError))
		})
	}
}

func TestRetry(t *testing.T) {
	ctx := context.Background()
	log := zaptest.NewLogger(t)

	cl := &ServiceClientGRPC{
		log: zaptest.NewLogger(t),
		clients: []TreeClient{
			&treeClientMock{address: "node0"},
			&treeClientMock{address: "node1"},
			&treeClientMock{address: "node2"},
			&treeClientMock{address: "node3"},
		},
	}

	makeFn := func(client grpcService.TreeServiceClient) error {
		return nil
	}

	t.Run("first ok", func(t *testing.T) {
		err := cl.requestWithRetry(ctx, log, makeFn)
		require.NoError(t, err)
		require.Equal(t, 0, cl.getStartIndex())
		resetClients(cl)
	})

	t.Run("first failed", func(t *testing.T) {
		setErrors(cl.clients[:1])
		err := cl.requestWithRetry(ctx, log, makeFn)
		require.NoError(t, err)
		require.Equal(t, 1, cl.getStartIndex())
		resetClients(cl)
	})

	t.Run("all failed", func(t *testing.T) {
		setErrors(cl.clients)
		err := cl.requestWithRetry(ctx, log, makeFn)
		require.Error(t, err)
		require.Equal(t, 0, cl.getStartIndex())
		resetClients(cl)
	})

	t.Run("round", func(t *testing.T) {
		setErrors(cl.clients[:2])
		err := cl.requestWithRetry(ctx, log, makeFn)
		require.NoError(t, err)
		require.Equal(t, 2, cl.getStartIndex())
		resetClientsErrors(cl)

		setErrors(cl.clients[2:])
		err = cl.requestWithRetry(ctx, log, makeFn)
		require.NoError(t, err)
		require.Equal(t, 0, cl.getStartIndex())
		resetClients(cl)
	})
}

func resetClients(cl *ServiceClientGRPC) {
	resetClientsErrors(cl)
	cl.setStartIndex(0)
}

func resetClientsErrors(cl *ServiceClientGRPC) {
	for _, client := range cl.clients {
		node := client.(*treeClientMock)
		node.err = false
	}
}

func setErrors(clients []TreeClient) {
	for _, client := range clients {
		node := client.(*treeClientMock)
		node.err = true
	}
}