@technobuddha/library

import { type Numbering } from './numbering.ts'; import { empty } from './unicode.ts'; /** * Represents the result of converting a number into its "illion" representation. * @internal */ type IllionReturn = { // The numeric value represented. quantity: number; // The corresponding "illion" word (e.g., "million", "billion"), or `null` if not applicable. word: string | null; // The mantissa part of the number as a string. mantissa: string; // The exponent part of the number. exponent: number; }; /** * Generates the "illion" name and associated information for a given number's mantissa and exponent. * * This function decomposes a number (represented by its mantissa and exponent) into a quantity, remaining mantissa, * adjusted exponent, and the corresponding "illion" word (e.g., "thousand", "million", "billion", etc.). * It supports extended illion names for very large numbers, following the Latin-based naming conventions. * @param argMantissa - The string representation of the number's mantissa (the significant digits). * @param argExponent - The exponent part of the number (power of 10). * @param shift - A boolean flag from the Numbering type indicating whether to shift and combine remaining mantissa digits into the quantity as a decimal. * @returns An object containing: * - `quantity`: The numeric value extracted from the mantissa for the current illion group. * - `mantissa`: The remaining mantissa string after extracting the quantity. * - `exponent`: The adjusted exponent after processing. * - `word`: The illion word corresponding to the exponent (or `null` if not applicable). * @remarks * - If the exponent is less than 3, the function returns with `word` as `null`. * - If the exponent is exactly 3, the function returns with `word` as `'thousand'`. * - For larger exponents, the function constructs the appropriate illion name using Latin prefixes and suffixes. * - The function supports fractional quantities if `shift` is true and there are remaining mantissa digits. * @internal */ export function illion( argMantissa: string, argExponent: number, shift: Numbering['shift'], ): IllionReturn { let mantissa = argMantissa; let exponent = argExponent; let factor = Math.floor((exponent - 3) / 3); let quantity = 0; switch (exponent - (factor * 3 + 3)) { case 0: { quantity = Number.parseInt(mantissa.padEnd(1, '0').slice(0, 1)); mantissa = mantissa.slice(1); exponent -= 1; break; } case 1: { quantity = Number.parseInt(mantissa.padEnd(2, '0').slice(0, 2)); mantissa = mantissa.slice(2); exponent -= 2; break; } case 2: { quantity = Number.parseInt(mantissa.padEnd(3, '0').slice(0, 3)); mantissa = mantissa.slice(3); exponent -= 3; break; } // no default } if (shift && mantissa.length > 0 && mantissa.length < 3 && Number.parseInt(mantissa) > 0) { quantity = Number.parseFloat(`${quantity}.${mantissa}`); exponent -= mantissa.length; mantissa = empty; } if (factor < 0) { return { quantity, mantissa, exponent, word: null }; } if (factor === 0) { return { quantity, mantissa, exponent, word: 'thousand' }; } let word = 'on'; while (factor > 0) { let a = false; // use the prefixed form; tens change end from 'i' to 'a' let s = false; // tre => tres; se => ses let x = false; // tre => tres; se => sex let m = false; // septe = septem; nove => novem let n = false; // septe = septen; nove => noven let d = false; // se => sex; nove => novem const factor0 = Math.floor(factor / 1) % 10; const factor1 = Math.floor(factor / 10) % 10; const factor2 = Math.floor(factor / 100) % 10; word = `lli${word}`; // hundreds switch (factor2) { case 1: { word = `centi${word}`; a = true; s = false; x = true; m = false; n = true; d = false; break; } case 2: { word = `ducenti${word}`; a = true; s = false; x = false; m = false; n = true; d = false; break; } case 3: { word = `trecenti${word}`; a = true; s = true; x = false; m = false; n = true; break; } case 4: { word = `quadringenti${word}`; a = true; s = true; x = false; m = false; n = true; d = false; break; } case 5: { word = `quingenti${word}`; a = true; s = true; x = false; m = false; n = true; d = false; break; } case 6: { word = `sescenti${word}`; a = true; s = false; x = false; m = false; n = true; d = false; break; } case 7: { word = `septingenti${word}`; a = true; s = false; x = false; m = false; n = true; d = false; break; } case 8: { word = `octingenti${word}`; a = true; s = false; x = true; m = true; n = false; d = false; break; } case 9: { word = `nongenti${word}`; a = true; s = false; x = false; m = false; n = false; d = false; break; } // no default } // tens switch (factor1) { case 1: { word = `deci${word}`; a = true; s = false; x = false; m = false; n = true; d = true; break; } case 2: { word = `viginti${word}`; a = true; s = true; x = false; m = true; n = false; d = false; break; } case 3: { word = (a ? 'triginta' : 'triginti') + word; a = true; s = true; x = false; m = false; n = true; d = false; break; } case 4: { word = (a ? 'quadraginta' : 'quadraginti') + word; a = true; s = true; x = false; m = false; n = true; d = false; break; } case 5: { word = (a ? 'quinginta' : 'quinginti') + word; a = true; s = true; x = false; m = false; n = true; d = false; break; } case 6: { word = (a ? 'sexaginta' : 'sexaginti') + word; a = true; s = false; x = false; m = false; n = false; d = false; break; } case 7: { word = (a ? 'septuaginta' : 'septuaginti') + word; a = true; s = false; x = false; m = false; n = true; d = false; break; } case 8: { word = (a ? 'octoginta' : 'octoginti') + word; a = true; s = false; x = true; m = true; n = false; d = false; break; } case 9: { word = (a ? 'nonaginta' : 'nonginti') + word; a = true; s = false; x = false; m = false; n = false; d = false; break; } // no default } // ones if (a) { switch (factor0) { case 1: { word = `un${word}`; break; } case 2: { word = `duo${word}`; break; } case 3: { word = (s ? 'tres' : x ? 'tres' : 'tre') + word; break; } case 4: { word = `quattuor${word}`; break; } case 5: { word = `quin${word}`; break; } case 6: { word = (x || d ? 'sex' : s ? 'ses' : 'se') + word; break; } case 7: { word = (n ? 'septen' : m ? 'septem' : 'septe') + word; break; } case 8: { word = `octo${word}`; break; } case 9: { word = (m || d ? 'novem' : n ? 'noven' : 'nove') + word; break; } // no default } } else { switch (factor0) { case 0: { word = `ni${word}`; break; } case 1: { word = `mi${word}`; break; } case 2: { word = `bi${word}`; break; } case 3: { word = `tri${word}`; break; } case 4: { word = `quadri${word}`; break; } case 5: { word = `quniti${word}`; break; } case 6: { word = `sexti${word}`; break; } case 7: { word = `septi${word}`; break; } case 8: { word = `octi${word}`; break; } case 9: { word = `noni${word}`; break; } // no default } } factor = Math.floor(factor / 1000); } return { quantity, mantissa: mantissa, exponent, word }; }