package cmd

import (
	"crypto/rand"
	"encoding/hex"
	"fmt"

	"git.maurice.fr/thomas/mailout/pkg/crypto"
	"git.maurice.fr/thomas/mailout/pkg/database"
	"git.maurice.fr/thomas/mailout/pkg/models"
	provider "git.maurice.fr/thomas/mailout/pkg/providers"
	"github.com/google/uuid"
	"github.com/pterm/pterm"
	"github.com/sirupsen/logrus"
	"github.com/spf13/cobra"
)

var (
	flagDKIMKeyActive bool
	flagSelector      string
	flagKeyBits       int
	flagProvider      string
)

var DKIMKeyCmd = &cobra.Command{
	Use:   "dkimkey",
	Short: "manages DKIM keys",
	PreRunE: func(cmd *cobra.Command, args []string) error {
		if flagProvider == "" {
			if cfg.Defaults.Provider == "" {
				logrus.Fatal("no provider specified and no default provider in config, aborting")
			}
			flagProvider = cfg.Defaults.Provider
		}

		return nil
	},
}

var DKIMKeyAddCmd = &cobra.Command{
	Use:   "add [domain]",
	Short: "adds a DKIM signing key",
	Args:  cobra.ExactArgs(1),
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		priv, pub, err := crypto.GenerateKeyPair(flagKeyBits)
		if err != nil {
			panic(err)
		}

		selector := flagSelector
		if selector == "" {
			b := make([]byte, 8)
			_, err := rand.Read(b)
			if err != nil {
				logrus.Fatal("entropy generator is kill")
			}

			selector = hex.EncodeToString(b)
		}

		dkimkey := models.DKIMKey{
			DomainName: args[0],
			PublicKey:  pub,
			PrivateKey: priv,
			Active:     flagUserActive,
			Selector:   selector,
			Record:     fmt.Sprintf("%s._domainkey.%s. IN TXT \"v=DKIM1; k=rsa; p=%s\"", selector, args[0], pub),
		}
		err = db.Save(&dkimkey).Error

		if err != nil {
			logrus.WithError(err).Fatal("could not create DKIM key")
		}

		logrus.Infof("created DKIM key %s", dkimkey.ID)
	},
}

var DKIMKeyListCmd = &cobra.Command{
	Use:   "list",
	Short: "list DKIM keys",
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		qRes := make([]models.DKIMKey, 0)

		err = db.Find(&qRes).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not list keys")
		}

		tData := pterm.TableData{
			{"id", "selector", "domain", "active", "created_at", "updated_at"},
		}
		for _, k := range qRes {
			tData = append(tData, []string{k.ID.String(), k.Selector, k.DomainName, fmt.Sprintf("%v", k.Active), k.CreatedAt.String(), k.UpdatedAt.String()})
		}

		pterm.DefaultTable.WithHasHeader().WithData(tData).Render()
	},
}

var DKIMKeyRecordCmd = &cobra.Command{
	Use:   "record",
	Short: "gives the dns record for a key",
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		qRes := make([]models.DKIMKey, 0)

		id, err := uuid.Parse(args[0])
		if err != nil {
			logrus.WithError(err).Fatal("invalid UUID")
		}

		err = db.Where(models.DKIMKey{ID: id}).Find(&qRes).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not search keys")
		}
		if len(qRes) == 0 {
			logrus.WithError(err).Fatal("No such key")
		}

		fmt.Println(qRes[0].Record)
	},
}

var DKIMKeyDeleteCmd = &cobra.Command{
	Use:   "delete",
	Short: "delete DKIM keys",
	Args:  cobra.ExactArgs(1),
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		id, err := uuid.Parse(args[0])
		if err != nil {
			logrus.WithError(err).Fatal("invalid UUID")
		}
		err = db.Where(&models.DKIMKey{ID: id}).Delete(&models.DKIMKey{}).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not delete DKIM key")
		}

		logrus.Infof("deleted DKIM key %s if it existed", args[0])
	},
}

var DKIMKeyActivateCmd = &cobra.Command{
	Use:   "activate",
	Short: "activates a DKIM key",
	Args:  cobra.ExactArgs(1),
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		id, err := uuid.Parse(args[0])
		if err != nil {
			logrus.WithError(err).Fatal("invalid UUID")
		}

		err = db.Model(&models.DKIMKey{}).Where(&models.DKIMKey{ID: id}).Update("active", true).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not activate DKIM key")
		}

		logrus.Infof("activated DKIM key %s", args[0])
	},
}

var DKIMKeyDeactivateCmd = &cobra.Command{
	Use:   "deactivate",
	Short: "deactivates a DKIM key",
	Args:  cobra.ExactArgs(1),
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		id, err := uuid.Parse(args[0])
		if err != nil {
			logrus.WithError(err).Fatal("invalid UUID")
		}

		err = db.Model(&models.DKIMKey{}).Where(&models.DKIMKey{ID: id}).Update("active", false).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not deactivate DKIM key")
		}

		logrus.Infof("deactivated DKIM key %s", args[0])
	},
}

var DKIMKeyPublishCmd = &cobra.Command{
	Use:   "publish",
	Short: "publishes a DKIM key onto a DNS provider",
	Args:  cobra.ExactArgs(1),
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		qRes := make([]models.DKIMKey, 0)

		id, err := uuid.Parse(args[0])
		if err != nil {
			logrus.WithError(err).Fatal("invalid UUID")
		}

		err = db.Where(models.DKIMKey{ID: id}).Find(&qRes).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not get key")
		}
		if len(qRes) == 0 {
			logrus.WithError(err).Fatal("No such key")
		}

		dkimkey := qRes[0]
		logger := logrus.WithFields(logrus.Fields{
			"dkimkey":  dkimkey.ID,
			"selector": dkimkey.Selector,
		})

		pv := flagProvider
		if flagProvider == "" {
			pv = cfg.Defaults.Provider
			if pv == "" {
				logrus.Fatal("no provider specified")
			}
		}

		pGen, ok := provider.Providers[pv]
		if !ok {
			logger.Fatalf("no such provider: %s", flagProvider)
		}

		p, err := pGen(cfg)
		if err != nil {
			logger.WithError(err).Fatal("could not create provider")
		}

		err = p.AddDKIMRecord(&dkimkey)
		if err != nil {
			logger.WithError(err).Fatal("could not publish dkim key")
		}

		logger.Info("successfully published record")
	},
}

var DKIMKeyUnpublishCmd = &cobra.Command{
	Use:   "unpublish",
	Short: "removes a DKIM key onto a DNS provider",
	Args:  cobra.ExactArgs(1),
	Run: func(cmd *cobra.Command, args []string) {
		db, err := database.NewDB(cfg)
		if err != nil {
			logrus.WithError(err).Fatal("could not connect to the database")
		}

		qRes := make([]models.DKIMKey, 0)

		id, err := uuid.Parse(args[0])
		if err != nil {
			logrus.WithError(err).Fatal("invalid UUID")
		}

		err = db.Where(models.DKIMKey{ID: id}).Find(&qRes).Error
		if err != nil {
			logrus.WithError(err).Fatal("could not get key")
		}
		if len(qRes) == 0 {
			logrus.WithError(err).Fatal("No such key")
		}

		dkimkey := qRes[0]

		logger := logrus.WithFields(logrus.Fields{
			"dkimkey":  dkimkey.ID,
			"selector": dkimkey.Selector,
		})

		pv := flagProvider
		if flagProvider == "" {
			pv = cfg.Defaults.Provider
			if pv == "" {
				logrus.Fatal("no provider specified")
			}
		}

		pGen, ok := provider.Providers[pv]
		if !ok {
			logger.Fatalf("no such provider: %s", flagProvider)
		}

		p, err := pGen(cfg)
		if err != nil {
			logger.WithError(err).Fatal("could not create provider")
		}

		err = p.DeleteDKIMRecord(&dkimkey)
		if err != nil {
			logger.WithError(err).Fatal("could not unpublish dkim key")
		}

		logger.Info("successfully unpublished record")
	},
}

func InitDKIMKeyCmd() {
	DKIMKeyCmd.AddCommand(DKIMKeyAddCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyListCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyDeleteCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyActivateCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyDeactivateCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyRecordCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyPublishCmd)
	DKIMKeyCmd.AddCommand(DKIMKeyUnpublishCmd)

	DKIMKeyAddCmd.PersistentFlags().BoolVarP(&flagDKIMKeyActive, "active", "a", true, "whether or not the created key is active")
	DKIMKeyAddCmd.PersistentFlags().StringVarP(&flagSelector, "selector", "s", "", "force a selector for the key")
	DKIMKeyAddCmd.PersistentFlags().IntVarP(&flagKeyBits, "key-bits", "k", 2048, "force a size for the key")

	DKIMKeyPublishCmd.PersistentFlags().StringVarP(&flagProvider, "provider", "p", "", "provider to which publish the change to")

	DKIMKeyUnpublishCmd.PersistentFlags().StringVarP(&flagProvider, "provider", "p", "", "provider to which unpublish the change from")
}