@tbela99/css-parser
Version:
CSS parser for node and the browser
102 lines (99 loc) • 3.18 kB
JavaScript
import { EnumToken } from '../types.js';
import { reduceNumber } from '../../renderer/render.js';
function gcd(x, y) {
x = Math.abs(x);
y = Math.abs(y);
let t;
if (x == 0 || y == 0) {
return 1;
}
while (y) {
t = y;
y = x % y;
x = t;
}
return x;
}
function compute(a, b, op) {
if (typeof a == 'number' && typeof b == 'number') {
switch (op) {
case EnumToken.Add:
return a + b;
case EnumToken.Sub:
return a - b;
case EnumToken.Mul:
return a * b;
case EnumToken.Div:
const r = simplify(a, b);
if (r[1] == 1) {
return r[0];
}
const result = a / b;
const r2 = reduceNumber(r[0]) + '/' + reduceNumber(r[1]);
return reduceNumber(result).length <= r2.length ? result : {
typ: EnumToken.FractionTokenType,
l: { typ: EnumToken.NumberTokenType, val: reduceNumber(r[0]) },
r: { typ: EnumToken.NumberTokenType, val: reduceNumber(r[1]) }
};
}
}
let l1 = typeof a == 'number' ? {
typ: EnumToken.FractionTokenType,
l: { typ: EnumToken.NumberTokenType, val: reduceNumber(a) },
r: { typ: EnumToken.NumberTokenType, val: '1' }
} : a;
let r1 = typeof b == 'number' ? {
typ: EnumToken.FractionTokenType,
l: { typ: EnumToken.NumberTokenType, val: reduceNumber(b) },
r: { typ: EnumToken.NumberTokenType, val: '1' }
} : b;
let l2;
let r2;
switch (op) {
case EnumToken.Add:
// @ts-ignore
l2 = l1.l.val * r1.r.val + l1.r.val * r1.l.val;
// @ts-ignore
r2 = l1.r.val * r1.r.val;
break;
case EnumToken.Sub:
// @ts-ignore
l2 = l1.l.val * r1.r.val - l1.r.val * r1.l.val;
// @ts-ignore
r2 = l1.r.val * r1.r.val;
break;
case EnumToken.Mul:
// @ts-ignore
l2 = l1.l.val * r1.l.val;
// @ts-ignore
r2 = l1.r.val * r1.r.val;
break;
case EnumToken.Div:
// @ts-ignore
l2 = l1.l.val * r1.r.val;
// @ts-ignore
r2 = l1.r.val * r1.l.val;
break;
}
const a2 = simplify(l2, r2);
if (a2[1] == 1) {
return a2[0];
}
const result = a2[0] / a2[1];
return reduceNumber(result).length <= reduceNumber(a2[0]).length + 1 + reduceNumber(a2[1]).length ? result : {
typ: EnumToken.FractionTokenType,
l: { typ: EnumToken.NumberTokenType, val: reduceNumber(a2[0]) },
r: { typ: EnumToken.NumberTokenType, val: reduceNumber(a2[1]) }
};
}
function rem(...a) {
if (a.some((i) => !Number.isInteger(i))) {
return a.reduce((a, b) => Math.max(a, String(b).split('.')[1]?.length ?? 0), 0);
}
return 0;
}
function simplify(a, b) {
const g = gcd(a, b);
return g > 1 ? [a / g, b / g] : [a, b];
}
export { compute, gcd, rem, simplify };