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

402 lines
9.9 KiB
TypeScript
Raw Normal View History

/**
* 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 { removeAccents } from "./accent-helpers";
export type DiacriticsAccumulator = { pIn: string, pOut: string };
type Consonant = "b" | "p" | "t" | "T" | "s" | "j" | "ch" | "kh" | "ts" | "dz" | "d" | "D" | "r" | "R" | "z" | "jz" | "G" | "sh" | "x" | "gh" | "f" | "q" | "k" | "g" | "l" | "m" | "n" | "N" | "h" | "w" | "y";
type Ain = "'"
type JoiningVowel = "-i-" | "-U-" | "-Ul-";
type LongVowel = "aa" | "ee" | "e" | "oo" | "o" | "ey" | "uy" | "eyy";
type ShortVowel = "a" | "i" | "u" | "U";
export type Phoneme = Consonant | Ain | LongVowel | ShortVowel | JoiningVowel;
type PhonemeInfo = {
matches?: string[],
beginningMatches?: string[],
endingMatches?: string[],
consonant?: true,
diacritic?: string,
endingOnly?: true,
takesSukunOnEnding?: true,
longVowel?: true,
canStartWithAynBefore?: true,
useEndingDiacritic?: true,
}
export const zwar = "َ";
export const zwarakey = "ٙ";
export const zer = "ِ";
export const pesh = "ُ";
export const sukun = "ْ";
export const hamzaAbove = "ٔ";
export const tashdeed = "ّ";
export const wasla = "ٱ";
export const daggerAlif = "ٰ";
export const fathahan = "ً";
export const phonemeTable: Record<Phoneme, PhonemeInfo> = {
// Consonants
"b": {
matches: ["ب"],
consonant: true,
},
"p": {
matches: ["پ"],
consonant: true,
},
"t": {
matches: ["ت", "ط"],
consonant: true,
},
"T": {
matches: ["ټ"],
consonant: true,
},
"s": {
matches: ["س", "ص", "ث"],
consonant: true,
},
"j": {
matches: ["ج"],
consonant: true,
},
"ch": {
matches: ["چ"],
consonant: true,
},
"kh": {
matches: ["خ"],
consonant: true,
},
"ts": {
matches: ["څ"],
consonant: true,
},
"dz": {
matches: ["ځ"],
consonant: true,
},
"d": {
matches: ["د"],
consonant: true,
},
"D": {
matches: ["ډ"],
consonant: true,
},
"r": {
matches: ["ر"],
consonant: true,
},
"R": {
matches: ["ړ"],
consonant: true,
},
"z": {
matches: ["ز", "ذ", "ظ", "ض"],
consonant: true,
},
"jz": {
matches: ["ژ"],
consonant: true,
},
"G": {
matches: ["ږ"],
consonant: true,
},
"sh": {
matches: ["ش"],
consonant: true,
},
"x": {
matches: ["ښ"],
consonant: true,
},
"gh": {
matches: ["غ"],
consonant: true,
},
"f": {
matches: ["ف"],
consonant: true,
},
"q": {
matches: ["ق"],
consonant: true,
},
"k": {
matches: ["ک"],
consonant: true,
},
"g": {
matches: ["ګ"],
consonant: true,
},
"l": {
matches: ["ل"],
consonant: true,
},
"m": {
matches: ["م"],
consonant: true,
},
"n": {
matches: ["ن"],
consonant: true,
},
"N": {
matches: ["ڼ"],
consonant: true,
},
"h": {
matches: ["ه", "ح"],
consonant: true,
takesSukunOnEnding: true,
},
"w": {
matches: ["و"],
consonant: true,
},
"y": {
matches: ["ی"],
consonant: true,
},
// Ain
"'": {
matches: ["ع", "ئ"],
consonant: true,
},
// Joining Vowels
"-i-": {
},
"-U-": {
matches: [" و ", "و"],
},
"-Ul-": {
matches: ["ال"],
},
// Long Vowels
"aa": {
matches: ["ا"],
beginningMatches: ["آ", "ا"],
endingMatches: ["ا", "یٰ"],
longVowel: true,
},
"ee": {
matches: ["ی"],
longVowel: true,
endingMatches: ["ي"],
diacritic: zer,
canStartWithAynBefore: true
},
"e": {
matches: ["ې"],
longVowel: true,
},
"o": {
matches: ["و"],
longVowel: true,
},
"oo": {
matches: ["و"],
longVowel: true,
// alsoCanBePrefix: true,
diacritic: pesh,
useEndingDiacritic: true,
},
"ey": {
matches: ["ی"],
longVowel: true,
endingMatches: ["ی"],
},
"uy": {
matches: ["ۍ"],
longVowel: true,
endingOnly: true,
},
"eyy": {
matches: ["ئ"],
longVowel: true,
endingOnly: true,
},
// Short Vowels
"a": {
diacritic: zwar,
endingMatches: ["ه"],
beginningMatches: ["ا", "ع"],
// canComeAfterHeyEnding: true,
// canBeFirstPartOfFathahanEnding: true,
},
"u": {
diacritic: zwarakey,
endingMatches: ["ه"],
},
"i": {
diacritic: zer,
endingMatches: ["ه"],
beginningMatches: ["ا", "ع"],
// takesDiacriticBeforeGurdaHeyEnding: true,
// canBeWasla: true,
},
"U": {
diacritic: pesh,
endingMatches: ["ه"],
// takesDiacriticBeforeGurdaHeyEnding: true,
beginningMatches: ["ا", "ع"],
},
}
/**
* splits a phonetics string into an array of Phonemes
*
* will error if there is an illeagal phonetics character
*
* @param fIn a phonetics string
* @returns an array of phonemes
*/
export function splitFIntoPhonemes(fIn: string): Phoneme[] {
const singleLetterPhonemes: Phoneme[] = ["a", "i", "u", "o", "e", "U", "b", "p", "t", "T", "s", "j", "d", "D", "r", "R", "z", "G", "x", "f", "q", "k", "g", "l", "m", "n", "N", "h", "w", "y"];
const quadrigraphs: Phoneme[] = ["-Ul-"];
const trigraphs: Phoneme[] = ["eyy", "-i-", "-U-"];
const digraphs: Phoneme[] = ["aa", "ee", "ey", "oo", "kh", "gh", "ts", "dz", "jz", "ch", "sh"];
const endingDigraphs: Phoneme[] = ["uy"];
const willIgnore = ["?", " ", "`", ".", "…", ",", "'"];
const result: Phoneme[] = [];
const f = removeAccents(fIn);
let index = 0;
while (index < f.length) {
const isLastTwoLetters = (index === f.length - 2 || f[index + 2] === " ");
const threeLetterChunk = f.slice(index, index + 3) as Phoneme;
const fourLetterChunk = f.slice(index, index + 4) as Phoneme;
if (quadrigraphs.includes(fourLetterChunk)) {
result.push(fourLetterChunk);
index += 4;
continue;
}
if (trigraphs.includes(threeLetterChunk)) {
result.push(threeLetterChunk);
index += 3;
continue;
}
const twoLetterChunk = f.slice(index, index + 2) as Phoneme;
if (
digraphs.includes(twoLetterChunk) ||
(isLastTwoLetters && endingDigraphs.includes(twoLetterChunk))
) {
result.push(twoLetterChunk);
index += 2;
continue;
}
const singleLetter = f.slice(index, index + 1) as Phoneme;
if (!willIgnore.includes(singleLetter)) {
if (!singleLetterPhonemes.includes(singleLetter)) {
throw new Error(`illegal phonetic character: ${singleLetter}`);
}
result.push(singleLetter);
}
index++;
}
return result;
}
/**
* returns the last character of a string
*
* @param s
*/
export function last(s: string) {
return s[s.length - 1];
}
export function advanceP(state: DiacriticsAccumulator, n: number = 1): DiacriticsAccumulator {
return {
pIn: state.pIn.slice(n),
pOut: state.pOut + state.pIn.slice(0, n),
};
}
/**
* moves back to the last character that wasn't a " " or "."
*
* @param state
* @returns
*/
export function reverseP(state: DiacriticsAccumulator): DiacriticsAccumulator {
const reversed = [...state.pOut].reverse();
const howFar = reversed.findIndex((c) => ![" ", "."].includes(c));
return {
pIn: state.pOut.slice(-howFar) + state.pIn,
pOut: state.pOut.slice(0, -howFar),
};
}
export const addP = (toAdd: string | undefined) => (state: DiacriticsAccumulator): DiacriticsAccumulator => {
return {
...state,
pOut: toAdd ? (state.pOut + toAdd) : state.pOut,
};
};
export const overwriteP = (toWrite: string) => (state: DiacriticsAccumulator): DiacriticsAccumulator => {
return {
pIn: state.pIn.slice(1),
pOut: state.pOut + toWrite,
};
};
/**
* returns the last two character in a string that was not a space or a dote
*
* @param s
* @returns
*/
export function prev2Chars(s: string): string {
// console.log("looking at pOut", s);
const reversed = [...s].reverse();
// console.log(reversed.join("-"));
const lastIndex = reversed.findIndex((c) => ![" ", "."].includes(c));
const last2 = reversed[lastIndex + 1] + reversed[lastIndex];
// console.log("last2", last2);
return last2;
}
export function getCurrentNext(state: DiacriticsAccumulator): { current: string, next: string} {
return {
current: state.pIn[0],
next: state.pIn[1],
};
}
export function advanceForAin(state: DiacriticsAccumulator): DiacriticsAccumulator {
const { current } = getCurrentNext(state);
return (current === "ع") ? advanceP(state) : state;
}
export function advanceForHamzaMid(state: DiacriticsAccumulator): DiacriticsAccumulator {
const { current, next } = getCurrentNext(state);
if (current === "ئ" && next && next !== "ئ") {
return advanceP(state);
}
return state;
}
export function advanceForAinOrHamza(state: DiacriticsAccumulator): DiacriticsAccumulator {
const { current, next } = getCurrentNext(state);
if (current === "ه" && (!next || next === " ")) {
return advanceP(state);
}
if (current === "ع") {
return advanceP(state);
}
return state;
}