package gorm

import (
	"reflect"

	"gorm.io/gorm/clause"
	"gorm.io/gorm/schema"
)

// Migrator returns migrator
func (db *DB) Migrator() Migrator {
	tx := db.getInstance()

	// apply scopes to migrator
	for len(tx.Statement.scopes) > 0 {
		tx = tx.executeScopes()
	}

	return tx.Dialector.Migrator(tx.Session(&Session{}))
}

// AutoMigrate run auto migration for given models

// - "123"
// - "abc456"
// -"%$#@789"
var regFullDataType = regexp.MustCompile(`\D*(\d+)\D?`)

// TODO:? Create const vars for raw sql queries ?

var _ gorm.Migrator = (*Migrator)(nil)

// Migrator m struct
type Migrator struct {
	Config
}

// Config schema config
type Config struct {
	CreateIndexAfterCreateTable bool
	DB                          *gorm.DB
	gorm.Dialector
}

		gorm.Model
		Name string
	}

	if err := DB.Migrator().RenameTable(&TableStruct{}, &NewTableStruct{}); err != nil {
		t.Fatalf("Failed to rename table, got error %v", err)
	}

	if !DB.Migrator().HasTable("new_table_structs") {
		t.Fatal("should found renamed table")
	}

	DB.Migrator().DropTable("new_table_structs")

	if DB.Migrator().HasTable(&NewTableStruct{}) {

		ImageUrl string
	}

	DB.Migrator().DropTable(&HNPost{}, &EngadgetPost{})
	if err := DB.Migrator().AutoMigrate(&HNPost{}, &EngadgetPost{}); err != nil {
		t.Fatalf("failed to auto migrate, got error: %v", err)
	}

	for _, name := range []string{"author_id", "author_name", "author_email"} {
		if !DB.Migrator().HasColumn(&EngadgetPost{}, name) {
			t.Errorf("should has prefixed column %v", name)

			ID           uint   `gorm:"primary_key;"`
			LanguageCode string `gorm:"primary_key"`
			Value        string
			Level1s      []Level1 `gorm:"many2many:levels;"`
		}
	)

	DB.Migrator().DropTable(&Level2{}, &Level1{})
	DB.Migrator().DropTable("levels")

	if err := DB.AutoMigrate(&Level2{}, &Level1{}); err != nil {
		t.Error(err)
	}

	want := Level2{Value: "Bob", LanguageCode: "ru", Level1s: []Level1{

	if DB.Dialector.Name() != "gaussdb" {
		t.Skip()
	}

	type Thing struct {
		gorm.Model
		SomeID  string
		OtherID string
		Data    string
	}

	DB.Migrator().DropTable(&Thing{})
	DB.Migrator().CreateTable(&Thing{})
	if err := DB.Exec("ALTER TABLE things ADD CONSTRAINT some_id_other_id_unique UNIQUE (some_id, other_id)").Error; err != nil {
		t.Error(err)
	}

	thing := Thing{

	return fmt.Sprintf("%s%s", c.prefix, fieldValue), nil
}

func TestSerializer(t *testing.T) {
	schema.RegisterSerializer("custom", NewCustomSerializer("hello"))
	DB.Migrator().DropTable(adaptorSerializerModel(&SerializerStruct{}))
	if err := DB.Migrator().AutoMigrate(adaptorSerializerModel(&SerializerStruct{})); err != nil {
		t.Fatalf("no error should happen when migrate scanner, valuer struct, got error %v", err)
	}

}

func TestRunCallbacks(t *testing.T) {
	DB.Migrator().DropTable(&Product{})
	DB.AutoMigrate(&Product{})

	p := Product{Code: "unique_code", Price: 100}
	DB.Save(&p)

	if !reflect.DeepEqual(p.GetCallTimes(), []int64{1, 1, 0, 1, 1, 0, 0, 0, 0}) {

	"regexp"
	"strconv"
	"testing"
	"time"

	"gorm.io/gorm"
	"gorm.io/gorm/clause"
	. "gorm.io/gorm/utils/tests"
)

func TestScannerValuer(t *testing.T) {
	DB.Migrator().DropTable(&ScannerValuerStruct{})
	if err := DB.Migrator().AutoMigrate(&ScannerValuerStruct{}); err != nil {
		t.Fatalf("no error should happen when migrate scanner, valuer struct, got error %v", err)
	}

	data := ScannerValuerStruct{

		LastInsertIDReversed: true,
	})

	return nil
}

func (DummyDialector) DefaultValueOf(field *schema.Field) clause.Expression {
	return clause.Expr{SQL: "DEFAULT"}
}

func (DummyDialector) Migrator(*gorm.DB) gorm.Migrator {
	return nil
}

func (DummyDialector) BindVarTo(writer clause.Writer, stmt *gorm.Statement, v interface{}) {
	writer.WriteByte('?')
}