amount formatter based on user's locale.

CurrencyFormatter.swift

extension Double {
    func formattedAsCurrency(_ currencySymbol: String? = nil) -> String {
        let formatter = NumberFormatter()
        formatter.numberStyle = .currency
        formatter.locale = Locale(identifier: "id_ID")
        if let currencySymbol {
            formatter.currencySymbol = currencySymbol
        }

        let price = NSNumber(value: self)
        if let amountString = formatter.string(from: price) {
            // check if it has default space like EUR
            let hasSpace = amountString.rangeOfCharacter(from: .whitespaces) != nil

//            let searchSymbol = self < 0 ? "-" + formatter.currencySymbol : formatter.currencySymbol!
            if let rangeOfSymbol = amountString.range(of: formatter.currencySymbol) {
                if amountString.startIndex == rangeOfSymbol.lowerBound {
                    formatter.paddingPosition = .afterPrefix
                } else {
                    formatter.paddingPosition = .beforeSuffix
                }
            }
            if !hasSpace {
                formatter.formatWidth = amountString.count + 1
                formatter.paddingCharacter = " "
            }
        } else {
            AppLogger.log("Error while making amount string from value: \(self)")
            return "\(self)"
        }
        
        return formatter.string(from: price) ?? "\(self)"
    }
}