type Writer interface {
	WriteByte(byte) error
	WriteString(string) (int, error)
}

// Builder builder interface
type Builder interface {
	Writer
	WriteQuoted(field interface{})
	AddVar(Writer, ...interface{})
	AddError(error) error
}

// Clause
type Clause struct {
	Name                string // WHERE
	BeforeExpression    Expression
	AfterNameExpression Expression

}

// Quote returns quoted value
func (stmt *Statement) Quote(field interface{}) string {
	var builder strings.Builder
	stmt.QuoteTo(&builder, field)
	return builder.String()
}

// AddVar add var
func (stmt *Statement) AddVar(writer clause.Writer, vars ...interface{}) {
	for idx, v := range vars {
		if idx > 0 {
			writer.WriteByte(',')
		}

		switch v := v.(type) {
		case sql.NamedArg:

	if len(set) > 0 {
		for idx, assignment := range set {
			if idx > 0 {
				builder.WriteByte(',')
			}
			builder.WriteQuoted(assignment.Column)
			builder.WriteByte('=')
			builder.AddVar(builder, assignment.Value)
		}
	} else {
		builder.WriteQuoted(Column{Name: PrimaryKey})
		builder.WriteByte('=')
		builder.WriteQuoted(Column{Name: PrimaryKey})
	}
}

// MergeClause merge assignments clauses

	sql.WriteString("CREATE ")
	if option.Replace {
		sql.WriteString("OR REPLACE ")
	}
	sql.WriteString("VIEW ")
	m.QuoteTo(sql, name)
	sql.WriteString(" AS ")

	m.DB.Statement.AddVar(sql, option.Query)

	if option.CheckOption != "" {
		sql.WriteString(" ")
		sql.WriteString(option.CheckOption)
	}
	return m.DB.Exec(m.Explain(sql.String(), m.DB.Statement.Vars...)).Error
}