quantityToScalar.ts

function findSuffix(quantity: string): string {
    let ix = quantity.length - 1;
    while (ix >= 0 && !/[\.0-9]/.test(quantity.charAt(ix))) {
        ix--;
    }
    return ix === -1 ? '' : quantity.substring(ix + 1);
}

function quantityToScalar(quantity: string): number | bigint {
    if (!quantity) {
        return 0;
    }
    switch (suffix) {
        case 'n':
            return Number(quantity.substr(0, quantity.length - 1)).valueOf() / 1_000_000_000.0;
        case 'u':
            return Number(quantity.substr(0, quantity.length - 1)).valueOf() / 1_000_000.0;
        case 'm':
            return Number(quantity.substr(0, quantity.length - 1)).valueOf() / 1000.0;
        case 'k':
            return BigInt(quantity.substr(0, quantity.length - 1)) * BigInt(1000);
        case 'M':
            return BigInt(quantity.substr(0, quantity.length - 1)) * BigInt(1000 * 1000);
        case 'G':
            return BigInt(quantity.substr(0, quantity.length - 1)) * BigInt(1000 * 1000 * 1000);
        case 'T':
            return (
                BigInt(quantity.substr(0, quantity.length - 1)) * BigInt(1000 * 1000 * 1000) * BigInt(1000)
            );
        case 'P':
            return (
                BigInt(quantity.substr(0, quantity.length - 1)) *
                BigInt(1000 * 1000 * 1000) *
                BigInt(1000 * 1000)
            );
        case 'E':
            return (
                BigInt(quantity.substr(0, quantity.length - 1)) *
                BigInt(1000 * 1000 * 1000) *
                BigInt(1000 * 1000 * 1000)
            );
        case 'Ki':
            return BigInt(quantity.substr(0, quantity.length - 2)) * BigInt(1024);
        case 'Mi':
            return BigInt(quantity.substr(0, quantity.length - 2)) * BigInt(1024 * 1024);
        case 'Gi':
            return BigInt(quantity.substr(0, quantity.length - 2)) * BigInt(1024 * 1024 * 1024);
        case 'Ti':
            return (
                BigInt(quantity.substr(0, quantity.length - 2)) * BigInt(1024 * 1024 * 1024) * BigInt(1024)
            );
        case 'Pi':
            return (
                BigInt(quantity.substr(0, quantity.length - 2)) *
                BigInt(1024 * 1024 * 1024) *
                BigInt(1024 * 1024)
            );
        case 'Ei':
            return (
                BigInt(quantity.substr(0, quantity.length - 2)) *
                BigInt(1024 * 1024 * 1024) *
                BigInt(1024 * 1024 * 1024)
            );
        default:
            throw new Error(`Unknown suffix: ${suffix}`);
    }
}