package sqlstore

import (
	"encoding/base64"
	"time"

	"github.com/grafana/grafana/pkg/bus"
	m "github.com/grafana/grafana/pkg/models"
	"github.com/grafana/grafana/pkg/setting"
	"github.com/grafana/grafana/pkg/util"
)

func init() {
	bus.AddHandler("sql", GetUserByAuthInfo)
	bus.AddHandler("sql", GetAuthInfo)
	bus.AddHandler("sql", SetAuthInfo)
	bus.AddHandler("sql", UpdateAuthInfo)
	bus.AddHandler("sql", DeleteAuthInfo)
}

func GetUserByAuthInfo(query *m.GetUserByAuthInfoQuery) error {
	user := &m.User{}
	has := false
	var err error
	authQuery := &m.GetAuthInfoQuery{}

	// Try to find the user by auth module and id first
	if query.AuthModule != "" && query.AuthId != "" {
		authQuery.AuthModule = query.AuthModule
		authQuery.AuthId = query.AuthId

		err = GetAuthInfo(authQuery)
		if err != m.ErrUserNotFound {
			if err != nil {
				return err
			}

			// if user id was specified and doesn't match the user_auth entry, remove it
			if query.UserId != 0 && query.UserId != authQuery.Result.UserId {
				err = DeleteAuthInfo(&m.DeleteAuthInfoCommand{
					UserAuth: authQuery.Result,
				})
				if err != nil {
					sqlog.Error("Error removing user_auth entry", "error", err)
				}

				authQuery.Result = nil
			} else {
				has, err = x.Id(authQuery.Result.UserId).Get(user)
				if err != nil {
					return err
				}

				if !has {
					// if the user has been deleted then remove the entry
					err = DeleteAuthInfo(&m.DeleteAuthInfoCommand{
						UserAuth: authQuery.Result,
					})
					if err != nil {
						sqlog.Error("Error removing user_auth entry", "error", err)
					}

					authQuery.Result = nil
				}
			}
		}
	}

	// If not found, try to find the user by id
	if !has && query.UserId != 0 {
		has, err = x.Id(query.UserId).Get(user)
		if err != nil {
			return err
		}
	}

	// If not found, try to find the user by email address
	if !has && query.Email != "" {
		user = &m.User{Email: query.Email}
		has, err = x.Get(user)
		if err != nil {
			return err
		}
	}

	// If not found, try to find the user by login
	if !has && query.Login != "" {
		user = &m.User{Login: query.Login}
		has, err = x.Get(user)
		if err != nil {
			return err
		}
	}

	// No user found
	if !has {
		return m.ErrUserNotFound
	}

	// create authInfo record to link accounts
	if authQuery.Result == nil && query.AuthModule != "" {
		cmd2 := &m.SetAuthInfoCommand{
			UserId:     user.Id,
			AuthModule: query.AuthModule,
			AuthId:     query.AuthId,
		}
		if err := SetAuthInfo(cmd2); err != nil {
			return err
		}
	}

	query.Result = user
	return nil
}

func GetAuthInfo(query *m.GetAuthInfoQuery) error {
	userAuth := &m.UserAuth{
		UserId:     query.UserId, // TODO this doesn't have an index in the db
		AuthModule: query.AuthModule,
		AuthId:     query.AuthId,
	}
	has, err := x.Desc("created").Get(userAuth)
	if err != nil {
		return err
	}
	if !has {
		return m.ErrUserNotFound
	}

	if userAuth.OAuthAccessToken != "" {
		decodedAccessToken, err := base64.StdEncoding.DecodeString(userAuth.OAuthAccessToken)
		if err != nil {
			return err
		}
		decryptedAccessToken, err := util.Decrypt(decodedAccessToken, setting.SecretKey)
		if err != nil {
			return err
		}
		userAuth.OAuthAccessToken = string(decryptedAccessToken)

	}
	if userAuth.OAuthRefreshToken != "" {
		decodedRefreshToken, err := base64.StdEncoding.DecodeString(userAuth.OAuthRefreshToken)
		if err != nil {
			return err
		}
		decryptedRefreshToken, err := util.Decrypt(decodedRefreshToken, setting.SecretKey)
		if err != nil {
			return err
		}
		userAuth.OAuthRefreshToken = string(decryptedRefreshToken)
	}
	if userAuth.OAuthTokenType != "" {
		decodedTokenType, err := base64.StdEncoding.DecodeString(userAuth.OAuthTokenType)
		if err != nil {
			return err
		}
		decryptedTokenType, err := util.Decrypt(decodedTokenType, setting.SecretKey)
		if err != nil {
			return err
		}
		userAuth.OAuthTokenType = string(decryptedTokenType)
	}

	query.Result = userAuth
	return nil
}

func SetAuthInfo(cmd *m.SetAuthInfoCommand) error {
	return inTransaction(func(sess *DBSession) error {
		authUser := &m.UserAuth{
			UserId:     cmd.UserId,
			AuthModule: cmd.AuthModule,
			AuthId:     cmd.AuthId,
			Created:    time.Now(),
		}

		if cmd.OAuthToken != nil {
			secretAccessToken, err := util.Encrypt([]byte(cmd.OAuthToken.AccessToken), setting.SecretKey)
			if err != nil {
				return err
			}
			secretRefreshToken, err := util.Encrypt([]byte(cmd.OAuthToken.RefreshToken), setting.SecretKey)
			if err != nil {
				return err
			}
			secretTokenType, err := util.Encrypt([]byte(cmd.OAuthToken.TokenType), setting.SecretKey)
			if err != nil {
				return err
			}

			authUser.OAuthAccessToken = base64.StdEncoding.EncodeToString(secretAccessToken)
			authUser.OAuthRefreshToken = base64.StdEncoding.EncodeToString(secretRefreshToken)
			authUser.OAuthTokenType = base64.StdEncoding.EncodeToString(secretTokenType)
			authUser.OAuthExpiry = cmd.OAuthToken.Expiry
		}

		_, err := sess.Insert(authUser)
		return err
	})
}

func UpdateAuthInfo(cmd *m.UpdateAuthInfoCommand) error {
	return inTransaction(func(sess *DBSession) error {
		authUser := &m.UserAuth{
			UserId:     cmd.UserId,
			AuthModule: cmd.AuthModule,
			AuthId:     cmd.AuthId,
			Created:    time.Now(),
		}

		if cmd.OAuthToken != nil {
			secretAccessToken, err := util.Encrypt([]byte(cmd.OAuthToken.AccessToken), setting.SecretKey)
			if err != nil {
				return err
			}
			secretRefreshToken, err := util.Encrypt([]byte(cmd.OAuthToken.RefreshToken), setting.SecretKey)
			if err != nil {
				return err
			}
			secretTokenType, err := util.Encrypt([]byte(cmd.OAuthToken.TokenType), setting.SecretKey)
			if err != nil {
				return err
			}
			authUser.OAuthAccessToken = base64.StdEncoding.EncodeToString(secretAccessToken)
			authUser.OAuthRefreshToken = base64.StdEncoding.EncodeToString(secretRefreshToken)
			authUser.OAuthTokenType = base64.StdEncoding.EncodeToString(secretTokenType)
			authUser.OAuthExpiry = cmd.OAuthToken.Expiry
		}

		cond := &m.UserAuth{
			UserId:     cmd.UserId,
			AuthModule: cmd.AuthModule,
		}

		_, err := sess.Update(authUser, cond)
		return err
	})
}

func DeleteAuthInfo(cmd *m.DeleteAuthInfoCommand) error {
	return inTransaction(func(sess *DBSession) error {
		_, err := sess.Delete(cmd.UserAuth)
		return err
	})
}