//// STRING TRANSFORMATION
/*jslint esversion: 6*/
// Note: 48 is the ASCII code for "0"
var str_transform = {
distanceDamerauLevenshtein2: function (s1, s2) {
// distance of Damerau-Levenshtein between <s1> and <s2>
// https://fr.wikipedia.org/wiki/Distance_de_Damerau-Levenshtein
try {
let nLen1 = s1.length;
let nLen2 = s2.length;
let matrix = [];
for (let i = 0; i <= nLen1; i++) {
matrix[i] = new Array(nLen2 + 1);
}
for (let i = 0; i <= nLen1; i++) {
matrix[i][0] = i;
}
for (let j = 0; j <= nLen2; j++) {
matrix[0][j] = j;
}
for (let i = 1; i <= nLen1; i++) {
for (let j = 1; j <= nLen2; j++) {
let nCost = (s1[i] === s2[j]) ? 0 : 1;
matrix[i][j] = Math.min(
matrix[i-1][j] + 1, // Deletion
matrix[i][j-1] + 1, // Insertion
matrix[i-1][j-1] + nCost // Substitution
);
if (i > 1 && j > 1 && s1[i] == s2[j-1] && s1[i-1] == s2[j]) {
matrix[i][j] = Math.min(matrix[i][j], matrix[i-2][j-2] + nCost); // Transposition
}
}
}
return matrix[nLen1][nLen2];
}
catch (e) {
helpers.logerror(e);
}
},
distanceDamerauLevenshtein: function (s1, s2) {
// distance of Damerau-Levenshtein between <s1> and <s2>
// https://fr.wikipedia.org/wiki/Distance_de_Damerau-Levenshtein
try {
let nLen1 = s1.length;
let nLen2 = s2.length;
let INF = nLen1 + nLen2;
let matrix = [];
let sd = {};
for (let i = 0; i < nLen1+2; i++) {
matrix[i] = new Array(nLen2+2);
}
matrix[0][0] = INF;
for (let i = 0; i <= nLen1; i++) {
matrix[i+1][1] = i;
matrix[i+1][0] = INF;
sd[s1[i]] = 0;
}
for (let j = 0; j <= nLen2; j++) {
matrix[1][j+1] = j;
matrix[0][j+1] = INF;
sd[s2[j]] = 0;
}
for (let i = 1; i <= nLen1; i++) {
let DB = 0;
for (let j = 1; j <= nLen2; j++) {
let i1 = sd[s2[j-1]];
let j1 = DB;
if (s1[i-1] === s2[j-1]) {
matrix[i+1][j+1] = matrix[i][j];
DB = j;
}
else {
matrix[i+1][j+1] = Math.min(matrix[i][j], Math.min(matrix[i+1][j], matrix[i][j+1])) + 1;
}
matrix[i+1][j+1] = Math.min(matrix[i+1][j+1], matrix[i1] ? matrix[i1][j1] + (i-i1-1) + 1 + (j-j1-1) : Infinity);
}
sd[s1[i-1]] = i;
}
return matrix[nLen1+1][nLen2+1];
}
catch (e) {
helpers.logerror(e);
}
},
showDistance (s1, s2) {
console.log(`Distance: ${s1} / ${s2} = ${this.distanceDamerauLevenshtein(s1, s2)})`);
},
// Suffix only
defineSuffixCode: function (sFlex, sStem) {
/*
Returns a string defining how to get stem from flexion
"n(sfx)"
with n: a char with numeric meaning, "0" = 0, "1" = 1, ... ":" = 10, etc. (See ASCII table.) Says how many letters to strip from flexion.
sfx [optional]: string to add on flexion
Examples:
"0": strips nothing, adds nothing
"1er": strips 1 letter, adds "er"
"2": strips 2 letters, adds nothing
*/
if (sFlex == sStem) {
return "0";
}
let jSfx = 0;
for (let i = 0; i < Math.min(sFlex.length, sStem.length); i++) {
if (sFlex[i] !== sStem[i]) {
break;
}
jSfx += 1;
}
return String.fromCharCode(sFlex.length-jSfx+48) + sStem.slice(jSfx);
},
getStemFromSuffixCode: function (sFlex, sSfxCode) {
// Suffix only
if (sSfxCode == "0") {
return sFlex;
}
return sSfxCode[0] == '0' ? sFlex + sSfxCode.slice(1) : sFlex.slice(0, -(sSfxCode.charCodeAt(0)-48)) + sSfxCode.slice(1);
},
getStemFromAffixCode: function (sFlex, sAffCode) {
// Prefix and suffix
if (sAffCode == "0") {
return sFlex;
}
if (!sAffCode.includes("/")) {
return "# error #";
}
let [sPfxCode, sSfxCode] = sAffCode.split('/');
sFlex = sPfxCode.slice(1) + sFlex.slice(sPfxCode.charCodeAt(0)-48);
return sSfxCode[0] == '0' ? sFlex + sSfxCode.slice(1) : sFlex.slice(0, -(sSfxCode.charCodeAt(0)-48)) + sSfxCode.slice(1);
}
};
if (typeof(exports) !== 'undefined') {
exports.getStemFromSuffixCode = str_transform.getStemFromSuffixCode;
exports.getStemFromAffixCode = str_transform.getStemFromAffixCode;
}