package oauthtoken

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

	"github.com/prometheus/client_golang/prometheus"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/mock"
	"golang.org/x/oauth2"
	"golang.org/x/sync/singleflight"

	"github.com/grafana/grafana/pkg/login/social/socialtest"
	"github.com/grafana/grafana/pkg/services/login"
	"github.com/grafana/grafana/pkg/services/login/authinfoimpl"
	"github.com/grafana/grafana/pkg/services/user"
	"github.com/grafana/grafana/pkg/setting"
)

func TestService_HasOAuthEntry(t *testing.T) {
	testCases := []struct {
		name            string
		user            *user.SignedInUser
		want            *login.UserAuth
		wantExist       bool
		wantErr         bool
		err             error
		getAuthInfoErr  error
		getAuthInfoUser login.UserAuth
	}{
		{
			name:      "returns false without an error in case user is nil",
			user:      nil,
			want:      nil,
			wantExist: false,
			wantErr:   false,
		},
		{
			name:           "returns false and an error in case GetAuthInfo returns an error",
			user:           &user.SignedInUser{UserID: 1},
			want:           nil,
			wantExist:      false,
			wantErr:        true,
			getAuthInfoErr: errors.New("error"),
		},
		{
			name:           "returns false without an error in case auth entry is not found",
			user:           &user.SignedInUser{UserID: 1},
			want:           nil,
			wantExist:      false,
			wantErr:        false,
			getAuthInfoErr: user.ErrUserNotFound,
		},
		{
			name:            "returns false without an error in case the auth entry is not oauth",
			user:            &user.SignedInUser{UserID: 1},
			want:            nil,
			wantExist:       false,
			wantErr:         false,
			getAuthInfoUser: login.UserAuth{AuthModule: "auth_saml"},
		},
		{
			name:            "returns true when the auth entry is found",
			user:            &user.SignedInUser{UserID: 1},
			want:            &login.UserAuth{AuthModule: "oauth_generic_oauth"},
			wantExist:       true,
			wantErr:         false,
			getAuthInfoUser: login.UserAuth{AuthModule: "oauth_generic_oauth"},
		},
	}
	for _, tc := range testCases {
		tc := tc
		t.Run(tc.name, func(t *testing.T) {
			srv, authInfoStore, _ := setupOAuthTokenService(t)
			authInfoStore.ExpectedOAuth = &tc.getAuthInfoUser
			authInfoStore.ExpectedError = tc.getAuthInfoErr

			entry, exists, err := srv.HasOAuthEntry(context.Background(), tc.user)

			if tc.wantErr {
				assert.Error(t, err)
			}

			if tc.want != nil {
				assert.True(t, reflect.DeepEqual(tc.want, entry))
			}
			assert.Equal(t, tc.wantExist, exists)
		})
	}
}

func TestService_TryTokenRefresh_ValidToken(t *testing.T) {
	srv, authInfoStore, socialConnector := setupOAuthTokenService(t)
	ctx := context.Background()
	token := &oauth2.Token{
		AccessToken:  "testaccess",
		RefreshToken: "testrefresh",
		Expiry:       time.Now(),
		TokenType:    "Bearer",
	}
	usr := &login.UserAuth{
		AuthModule:        "oauth_generic_oauth",
		OAuthAccessToken:  token.AccessToken,
		OAuthRefreshToken: token.RefreshToken,
		OAuthExpiry:       token.Expiry,
		OAuthTokenType:    token.TokenType,
	}

	authInfoStore.ExpectedOAuth = usr

	socialConnector.On("TokenSource", mock.Anything, mock.Anything).Return(oauth2.StaticTokenSource(token))

	err := srv.TryTokenRefresh(ctx, usr)
	assert.Nil(t, err)
	socialConnector.AssertNumberOfCalls(t, "TokenSource", 1)

	authInfoQuery := &login.GetAuthInfoQuery{}
	resultUsr, err := srv.AuthInfoService.GetAuthInfo(ctx, authInfoQuery)

	assert.Nil(t, err)

	// User's token data had not been updated
	assert.Equal(t, resultUsr.OAuthAccessToken, token.AccessToken)
	assert.Equal(t, resultUsr.OAuthExpiry, token.Expiry)
	assert.Equal(t, resultUsr.OAuthRefreshToken, token.RefreshToken)
	assert.Equal(t, resultUsr.OAuthTokenType, token.TokenType)
}

func TestService_TryTokenRefresh_NoRefreshToken(t *testing.T) {
	srv, _, socialConnector := setupOAuthTokenService(t)
	ctx := context.Background()
	token := &oauth2.Token{
		AccessToken:  "testaccess",
		RefreshToken: "",
		Expiry:       time.Now().Add(-time.Hour),
		TokenType:    "Bearer",
	}
	usr := &login.UserAuth{
		AuthModule:        "oauth_generic_oauth",
		OAuthAccessToken:  token.AccessToken,
		OAuthRefreshToken: token.RefreshToken,
		OAuthExpiry:       token.Expiry,
		OAuthTokenType:    token.TokenType,
	}

	socialConnector.On("TokenSource", mock.Anything, mock.Anything).Return(oauth2.StaticTokenSource(token))

	err := srv.TryTokenRefresh(ctx, usr)

	assert.NotNil(t, err)
	assert.ErrorIs(t, err, ErrNoRefreshTokenFound)

	socialConnector.AssertNotCalled(t, "TokenSource")
}

func TestService_TryTokenRefresh_ExpiredToken(t *testing.T) {
	srv, authInfoStore, socialConnector := setupOAuthTokenService(t)
	ctx := context.Background()
	token := &oauth2.Token{
		AccessToken:  "testaccess",
		RefreshToken: "testrefresh",
		Expiry:       time.Now().Add(-time.Hour),
		TokenType:    "Bearer",
	}

	newToken := &oauth2.Token{
		AccessToken:  "testaccess_new",
		RefreshToken: "testrefresh_new",
		Expiry:       time.Now().Add(time.Hour),
		TokenType:    "Bearer",
	}

	usr := &login.UserAuth{
		AuthModule:        "oauth_generic_oauth",
		OAuthAccessToken:  token.AccessToken,
		OAuthRefreshToken: token.RefreshToken,
		OAuthExpiry:       token.Expiry,
		OAuthTokenType:    token.TokenType,
	}

	authInfoStore.ExpectedOAuth = usr

	socialConnector.On("TokenSource", mock.Anything, mock.Anything).Return(oauth2.ReuseTokenSource(token, oauth2.StaticTokenSource(newToken)), nil)

	err := srv.TryTokenRefresh(ctx, usr)

	assert.Nil(t, err)
	socialConnector.AssertNumberOfCalls(t, "TokenSource", 1)

	authInfoQuery := &login.GetAuthInfoQuery{}
	authInfo, err := srv.AuthInfoService.GetAuthInfo(ctx, authInfoQuery)

	assert.Nil(t, err)

	// newToken should be returned after the .Token() call, therefore the User had to be updated
	assert.Equal(t, authInfo.OAuthAccessToken, newToken.AccessToken)
	assert.Equal(t, authInfo.OAuthExpiry, newToken.Expiry)
	assert.Equal(t, authInfo.OAuthRefreshToken, newToken.RefreshToken)
	assert.Equal(t, authInfo.OAuthTokenType, newToken.TokenType)
}

func TestService_TryTokenRefresh_DifferentAuthModuleForUser(t *testing.T) {
	srv, _, socialConnector := setupOAuthTokenService(t)
	ctx := context.Background()
	token := &oauth2.Token{}
	usr := &login.UserAuth{
		AuthModule: "auth.saml",
	}

	socialConnector.On("TokenSource", mock.Anything, mock.Anything).Return(oauth2.StaticTokenSource(token))

	err := srv.TryTokenRefresh(ctx, usr)

	assert.NotNil(t, err)
	assert.ErrorIs(t, err, ErrNotAnOAuthProvider)

	socialConnector.AssertNotCalled(t, "TokenSource")
}

func setupOAuthTokenService(t *testing.T) (*Service, *FakeAuthInfoStore, *socialtest.MockSocialConnector) {
	t.Helper()

	socialConnector := &socialtest.MockSocialConnector{}
	socialService := &socialtest.FakeSocialService{
		ExpectedConnector: socialConnector,
	}

	authInfoStore := &FakeAuthInfoStore{}
	authInfoService := authinfoimpl.ProvideService(authInfoStore)
	return &Service{
		Cfg:                  setting.NewCfg(),
		SocialService:        socialService,
		AuthInfoService:      authInfoService,
		singleFlightGroup:    &singleflight.Group{},
		tokenRefreshDuration: newTokenRefreshDurationMetric(prometheus.NewRegistry()),
	}, authInfoStore, socialConnector
}

type FakeAuthInfoStore struct {
	login.Store
	ExpectedError error
	ExpectedOAuth *login.UserAuth
}

func (f *FakeAuthInfoStore) GetAuthInfo(ctx context.Context, query *login.GetAuthInfoQuery) (*login.UserAuth, error) {
	return f.ExpectedOAuth, f.ExpectedError
}

func (f *FakeAuthInfoStore) SetAuthInfo(ctx context.Context, cmd *login.SetAuthInfoCommand) error {
	return f.ExpectedError
}

func (f *FakeAuthInfoStore) UpdateAuthInfo(ctx context.Context, cmd *login.UpdateAuthInfoCommand) error {
	f.ExpectedOAuth.OAuthAccessToken = cmd.OAuthToken.AccessToken
	f.ExpectedOAuth.OAuthExpiry = cmd.OAuthToken.Expiry
	f.ExpectedOAuth.OAuthTokenType = cmd.OAuthToken.TokenType
	f.ExpectedOAuth.OAuthRefreshToken = cmd.OAuthToken.RefreshToken
	return f.ExpectedError
}

func (f *FakeAuthInfoStore) DeleteAuthInfo(ctx context.Context, cmd *login.DeleteAuthInfoCommand) error {
	return f.ExpectedError
}