pashto-inflector/src/lib/accent-helpers.ts

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2021-03-09 12:39:13 +00:00
/**
* Copyright (c) 2021 lingdocs.com
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
*/
import { makePsString } from "./p-text-helpers";
import * as T from "../types";
/**
* Returns a Pashto string (or string with Length options) ensuring that
* the accent is on front
*
* @param s
*/
export function accentOnFront(s: T.SingleOrLengthOpts<T.PsString>): T.SingleOrLengthOpts<T.PsString> {
if ("long" in s) {
return {
short: accentOnFront(s.short) as T.PsString,
long: accentOnFront(s.long) as T.PsString,
};
}
return {
...s,
f: accentSyllable(removeAccents(s.f)),
};
}
/**
* Ensures an accent on a past participle ie. leedúley, préxey, azmóyuley
*
* @param s - the Pashto string (with Pashto and Phonetics) to ensure the accent on
*/
export function accentPastParticiple(s: T.PsString): T.PsString {
// check for accent placing in words like wáayuley and azmóyuley
const accentFallsOnThirdLast = (syls: string[]) => {
if (syls.length < 3) return false;
const secondLast = syls[syls.length-2];
const thirdLast = syls[syls.length-3];
const lastLetterOfThirdLast = thirdLast.slice(-1);
return (
(secondLast === "ul") && (lastLetterOfThirdLast === "y")
);
}
// remove all accents
const accentsRemoved = removeAccents(s.f);
// split up the syllables (preserving the spaces)
const syllables = splitUpSyllables(accentsRemoved);
// add an accent on the appropriate syllable
const n = accentFallsOnThirdLast(syllables) ? 2 : 1;
const accentedF = accentFSylsOnNFromEnd(syllables, n);
return makePsString(s.p, accentedF);
}
export function splitUpSyllables(s: string): string[] {
return s.match(/ |([^a|e|i|o|u| ]*(aa|a|ey|ee|e|oo|o|i|u)[^a|e|i|o|u| ]*)/g) as string[];
}
/**
* Returns a phonetic string with the accent placed n syllables from the end
*
* @param syls - an array of syllables in phonetic strings without accents (including spaces as extra items)
* @param n - the number of syllables from the end to put the accent
*/
export function accentFSylsOnNFromEnd(syls: string[], n: number): string {
return [
...syls.slice(0, syls.length-(n+1)), // before accent
accentSyllable(syls[syls.length-(n+1)]), // syllable to be accented
...(n !== 0) ? syls.slice(syls.length-n) : [], // after syllable to be accented
].join("");
}
export function accentOnNFromEnd(ps: T.PsString, n: number): T.PsString {
const fSyls = splitUpSyllables(removeAccents(ps.f));
return makePsString(
ps.p,
accentFSylsOnNFromEnd(fSyls, n),
);
}
function accentSyllable(s: string): string {
const replacer = [
{ vowel: "a", accented: "á" },
{ vowel: "e", accented: "é" },
{ vowel: "i", accented: "í" },
{ vowel: "o", accented: "ó" },
{ vowel: "u", accented: "ú" },
{ vowel: "U", accented: "Ú" },
];
return s.replace(/a|e|i|o|u|U/, (match) => {
const r = replacer.find((x) => x.vowel === match);
/* istanbul ignore next */
return r?.accented || "";
});
}
export function removeAccents(s: T.PsString): T.PsString;
export function removeAccents(s: string): string;
export function removeAccents(s: T.PsString | string): T.PsString | string {
if (typeof s !== "string") {
return makePsString(
s.p,
removeAccents(s.f),
);
}
return s.replace(/á/g, "a")
.replace(/é/g, "e")
.replace(/í/g, "i")
.replace(/ó/g, "o")
.replace(/ú/g, "u")
.replace(/Á/g, "A")
.replace(/Ú/g, "U");
}