package schema

import (
	"regexp"
	"strings"

	"gorm.io/gorm/clause"
)

// reg match english letters and midline
var regEnLetterAndMidline = regexp.MustCompile(`^[\w-]+$`)

type CheckConstraint struct {
	Name       string
	Constraint string // length(phone) >= 10
	*Field
}

func (chk *CheckConstraint) GetName() string { return chk.Name }

func (chk *CheckConstraint) Build() (sql string, vars []interface{}) {

	"encoding/gob"
	"encoding/json"
	"fmt"
	"reflect"
	"strings"
	"sync"
	"time"
)

var serializerMap = sync.Map{}

// RegisterSerializer register serializer
func RegisterSerializer(name string, serializer SerializerInterface) {
	serializerMap.Store(strings.ToLower(name), serializer)
}

// GetSerializer get serializer
func GetSerializer(name string) (serializer SerializerInterface, ok bool) {

	set := clause.Assignments(map[string]interface{}{
		"name": "jinzhu",
		"age":  18,
	})

	assignments := []clause.Assignment(set)

	sort.Slice(assignments, func(i, j int) bool {
		return strings.Compare(assignments[i].Column.Name, assignments[j].Column.Name) > 0
	})

		t.Fatalf("Build count with select, but got %v", result.Statement.SQL.String())
	}

	result = dryDB.Table("users").Distinct("name").Count(&count)
	if !regexp.MustCompile(`SELECT COUNT\(DISTINCT\(.name.\)\) FROM .*users.*`).MatchString(result.Statement.SQL.String()) {
		t.Fatalf("Build count with select, but got %v", result.Statement.SQL.String())
	}

	var count4 int64

	"crypto/sha1"
	"encoding/hex"
	"regexp"
	"strings"
	"unicode/utf8"

	"github.com/jinzhu/inflection"
)

// Namer namer interface
type Namer interface {
	TableName(table string) string
	SchemaName(table string) string
	ColumnName(table, column string) string
	JoinTableName(joinTable string) string
	RelationshipFKName(Relationship) string
	CheckerName(table, column string) string
	IndexName(table, column string) string

// NestedRelationName nested relationships like `Manager__Company`
func NestedRelationName(prefix, name string) string {
	return prefix + nestedRelationSplit + name
}

// SplitNestedRelationName Split nested relationships to `[]string{"Manager","Company"}`
func SplitNestedRelationName(name string) []string {
	return strings.Split(name, nestedRelationSplit)
}

// JoinNestedRelationNames nested relationships like `Manager__Company`

	default:
		return false
	}
}

// ExplainSQL generate SQL string with given parameters, the generated SQL is expected to be used in logger, execute it might introduce a SQL injection vulnerability
func ExplainSQL(sql string, numericPlaceholder *regexp.Regexp, escaper string, avars ...interface{}) string {
	var (
		convertParams func(interface{}, int)
		vars          = make([]string, len(avars))
	)

	convertParams = func(v interface{}, idx int) {

// Table specify the table you would like to run db operations
//
//	// Get a user
//	db.Table("users").Take(&result)
func (db *DB) Table(name string, args ...interface{}) (tx *DB) {
	tx = db.getInstance()
	if strings.Contains(name, " ") || strings.Contains(name, "`") || len(args) > 0 {
		tx.Statement.TableExpr = &clause.Expr{SQL: name, Vars: args}
		if results := tableRegexp.FindStringSubmatch(name); len(results) == 3 {

		return nil
	}

	// found, smart migrate
	fullDataType := strings.TrimSpace(strings.ToLower(m.DB.Migrator().FullDataTypeOf(field).SQL))
	realDataType := strings.ToLower(columnType.DatabaseTypeName())

	var (
		alterColumn bool
		isSameType  = fullDataType == realDataType
	)

	if !field.PrimaryKey {
		// check type
		if !strings.HasPrefix(fullDataType, realDataType) {
			// check type aliases

										where.Build(&onStmt)

										if onSQL := onStmt.SQL.String(); onSQL != "" {
											vars := onStmt.Vars
											for idx, v := range vars {
												bindvar := strings.Builder{}
												onStmt.Vars = vars[0 : idx+1]
												db.Dialector.BindVarTo(&bindvar, &onStmt, v)
												onSQL = strings.Replace(onSQL, bindvar.String(), "?", 1)
											}