package migrations

import (
	"github.com/emvi/logbuch"
	"github.com/muety/wakapi/config"
	"github.com/muety/wakapi/models"
	"gorm.io/gorm"
)

func init() {
	const name = "20210202-fix_cascade_for_alias_user_constraint"

	f := migrationFunc{
		name: name,
		f: func(db *gorm.DB, cfg *config.Config) error {
			migrator := db.Migrator()

			if cfg.Db.Dialect == config.SQLDialectSqlite {
				// see 20201106_migration_cascade_constraints
				logbuch.Info("not attempting to drop and regenerate constraints on sqlite")
				return nil
			}

			if !migrator.HasTable(&models.KeyStringValue{}) {
				logbuch.Info("key-value table not yet existing")
				return nil
			}

			condition := "key = ?"
			if cfg.Db.Dialect == config.SQLDialectMysql {
				condition = "`key` = ?"
			}
			lookupResult := db.Where(condition, name).First(&models.KeyStringValue{})
			if lookupResult.Error == nil && lookupResult.RowsAffected > 0 {
				logbuch.Info("no need to migrate '%s'", name)
				return nil
			}

			if migrator.HasConstraint(&models.Alias{}, "fk_aliases_user") {
				logbuch.Info("dropping constraint 'fk_aliases_user'")
				if err := migrator.DropConstraint(&models.Alias{}, "fk_aliases_user"); err != nil {
					return err
				}
			}

			if err := db.Create(&models.KeyStringValue{
				Key:   name,
				Value: "done",
			}).Error; err != nil {
				return err
			}

			return nil
		},
	}

	registerPreMigration(f)
}