import { PriceOptions } from './types';

class Price {
    readonly currencyUnit: string;
    readonly currencyTemplate: {};

    constructor(options: PriceOptions) {
        this.currencyUnit = options.currencyUnit;
        this.currencyTemplate =
            {
                'USD': '${money}{.}{2}',
                'VND': '{money}{,}{0}₫',
                'JPY': '¥{money}{.}{0}',
                'EUR': '{money}{,}{2}€',
                'GBP': '£{money}{.}{2}',
                'CAD': 'CA${money}{.}{2}',
                'AUD': 'AU${money}{.}{2}',
                'KRW': '₩{money}{,}{0}',
                'PLN': '{money}{,}{2}zł'
            }
        ;
    }

    formatPrice(price: number) {
        let template = this.getTemplatePrice();
        if (!template) {
            return this.formatNumber(price, ',', '.') + ' ₫';
        } else {
            let retVal = this.formatNumber(price, ',', '.') + ' ₫';
            let matches = template.match(/{money}{([^a-zA-z0-9]+)}{([0-9]+)}/);
            if (!matches) {
                throw new Error('Invalid price template');
            }
            
            if (matches.length > 2) {
                let separate = matches[1];
                let number = parseInt(matches[2]);
                template = template.replace(/{([^a-zA-z0-9]+)}/, '');
                template = template.replace(/{([0-9]+)}/, '');
                let decimal = separate == '.' ? ',' : '.';
                retVal = template.replace('{money}', this.formatNumber(price, separate, decimal, number));
            }

            return retVal;
        }
    }

    private getTemplatePrice() {
        // @ts-ignore
        return this.currencyTemplate[this.currencyUnit];
    }

    private formatNumber(price: number, desSep = ',', groupSep = '.', number = 0) {
        if (price != parseFloat(String(price))) {
            price = 0;
        }

        let newStr = '';
        price = parseFloat(String(price));
        const p = price.toFixed(number).split(".");
        const chars = p[0].split("").reverse();
        let count = 0;
        for (let x = 0; x < chars.length; x++) {
            count++;
            if (count % 3 == 1 && count != 1) {
                newStr = chars[x] + groupSep + newStr;
            } else {
                newStr = chars[x] + newStr;
            }
        }

        if (p.length > 1) {
            newStr += desSep + p[1];
        } else if (number > 0) {
            newStr += desSep;
            for (let i = 0; i < number; i++) {
                newStr += '0';
            }
        }

        return newStr;
    }
}

export default Price;