package bolt

import (
	"fmt"

	portainer "github.com/portainer/portainer/api"
	errors "github.com/portainer/portainer/api/bolt/errors"
	plog "github.com/portainer/portainer/api/bolt/log"
	"github.com/portainer/portainer/api/bolt/migrator"
	"github.com/portainer/portainer/api/cli"
	"github.com/portainer/portainer/api/internal/authorization"
)

const beforePortainerUpgradeToEEBackup = "portainer.db.before-EE-upgrade"

var migrateLog = plog.NewScopedLog("bolt, migrate")

// FailSafeMigrate backup and restore DB if migration fail
func (store *Store) FailSafeMigrate(migrator *migrator.Migrator, version int) error {
	defer func() {
		if err := recover(); err != nil {
			migrateLog.Info(fmt.Sprintf("Error during migration, recovering [%v]", err))
			store.Restore()
		}
	}()
	return migrator.Migrate(version)
}

// MigrateData automatically migrate the data based on the DBVersion.
// This process is only triggered on an existing database, not if the database was just created.
// if force is true, then migrate regardless.
func (store *Store) MigrateData(force bool) error {
	// 0 – if DB is new then we don't need to migrate any data and just set version and edition to latest EE
	if store.isNew && !force {
		err := store.VersionService.StoreDBVersion(portainer.DBVersionEE)
		if err != nil {
			return err
		}

		err = store.VersionService.StoreEdition(portainer.PortainerEE)
		if err != nil {
			return err
		}

		return nil
	}

	migrator, err := store.newMigrator()
	if err != nil {
		return err
	}

	if migrator.Edition() == portainer.PortainerCE {
		// backup before migrating
		store.BackupWithOptions(&BackupOptions{
			BackupFileName: beforePortainerUpgradeToEEBackup,
			Edition:        portainer.PortainerCE,
		})

		store.VersionService.StorePreviousDBVersion(migrator.Version())

		// 1 – We need to migrate DB to latest CE version

		if migrator.Version() < portainer.DBVersion {
			store.Backup()
			err = store.FailSafeMigrate(migrator, portainer.DBVersion)
			if err != nil {
				store.Restore()
				migrateLog.Error("An error occurred while migrating CE database to latest version", err)
				return err
			}
		}

	}

	if portainer.Edition == portainer.PortainerEE {
		// 2 – if DB is CE Edition we need to upgrade settings to EE
		if migrator.Edition() < portainer.PortainerEE {
			err = migrator.UpgradeToEE()
			if err != nil {
				migrateLog.Error("An error occurred while upgrading database to EE", err)
				store.RollbackFailedUpgradeToEE()
				return err
			}

		}

		// 3 – if DB is EE Edition we need to migrate to latest version of EE
		if migrator.Edition() == portainer.PortainerEE && migrator.Version() < portainer.DBVersionEE {
			store.Backup()
			err = store.FailSafeMigrate(migrator, portainer.DBVersionEE)
			if err != nil {
				migrateLog.Error("An error occurred while migrating EE database to latest version", err)
				store.Restore()
				return err
			}
		}
	}

	return nil
}

// RollbackFailedUpgradeToEE down migrate to previous version
func (store *Store) RollbackFailedUpgradeToEE() error {
	return store.RestoreWithOptions(&BackupOptions{
		BackupFileName: beforePortainerUpgradeToEEBackup,
		Edition:        portainer.PortainerCE,
	})
}

// RollbackToCE rollbacks the store to the current ce version
func (store *Store) RollbackToCE() error {

	migrator, err := store.newMigrator()
	if err != nil {
		return err
	}

	migrateLog.Info(fmt.Sprintf("Current Software Edition: %s", migrator.Edition().GetEditionLabel()))
	migrateLog.Info(fmt.Sprintf("Current DB Version: %d", migrator.Version()))

	if migrator.Edition() == portainer.PortainerCE {
		return errors.ErrMigrationToCE
	}

	previousVersion, err := store.VersionService.PreviousDBVersion()
	if err != nil {
		migrateLog.Error("An Error occurred with retrieving previous DB version", err)
		return err
	}

	confirmed, err := cli.Confirm(fmt.Sprintf("Are you sure you want to rollback your database to %d?", previousVersion))
	if err != nil || !confirmed {
		return err
	}

	if previousVersion < 25 {
		migrator.DowngradeSettingsFrom25()
	}

	err = store.VersionService.StoreDBVersion(previousVersion)
	if err != nil {
		migrateLog.Error(fmt.Sprintf("An Error occurred with rolling back to CE Edition, DB Version %d", previousVersion), err)
		return err
	}

	err = store.VersionService.StoreEdition(portainer.PortainerCE)
	if err != nil {
		migrateLog.Error(fmt.Sprintf("An Error occurred with rolling back to CE Edition, DB Version %d", previousVersion), err)
		return err
	}

	migrateLog.Info(fmt.Sprintf("Rolled back to CE Edition, DB Version %d", previousVersion))
	return nil
}

func (store *Store) newMigrator() (*migrator.Migrator, error) {

	version, err := store.version()
	if err != nil {
		return nil, err
	}

	edition := store.edition()

	params := &migrator.Parameters{
		DB:              store.connection.DB,
		DatabaseVersion: version,
		CurrentEdition:  edition,

		EndpointGroupService:    store.EndpointGroupService,
		EndpointService:         store.EndpointService,
		EndpointRelationService: store.EndpointRelationService,
		ExtensionService:        store.ExtensionService,
		RegistryService:         store.RegistryService,
		ResourceControlService:  store.ResourceControlService,
		RoleService:             store.RoleService,
		ScheduleService:         store.ScheduleService,
		SettingsService:         store.SettingsService,
		StackService:            store.StackService,
		TagService:              store.TagService,
		TeamMembershipService:   store.TeamMembershipService,
		UserService:             store.UserService,
		VersionService:          store.VersionService,
		FileService:             store.fileService,
		AuthorizationService:    authorization.NewService(store),
	}

	return migrator.NewMigrator(params), nil
}

// RollbackVersion down migrate to previous version
func (store *Store) RollbackVersion(version int) error {
	// TODO
	backupLog.NotImplemented("RollbackVersion")
	return nil
}

// RollbackEdition downgrade to previous edition
func (store *Store) RollbackEdition(edition portainer.SoftwareEdition) error {
	// TODO
	backupLog.NotImplemented("RollbackEdition")
	// Change Edition
	// Migrate Services
	// Restore Latest
	return nil
}