blob: 14b243198f7b255e6ba8ae8f1e7a0e2c0db7fc90 [file] [log] [blame]
"use strict";
/**
* @typedef {[number, boolean]} RangeValue
*/
/**
* @callback RangeValueCallback
* @param {RangeValue} rangeValue
* @returns {boolean}
*/
class Range {
/**
* @param {"left" | "right"} side
* @param {boolean} exclusive
* @returns {">" | ">=" | "<" | "<="}
*/
static getOperator(side, exclusive) {
if (side === "left") {
return exclusive ? ">" : ">=";
}
return exclusive ? "<" : "<=";
}
/**
* @param {number} value
* @param {boolean} logic is not logic applied
* @param {boolean} exclusive is range exclusive
* @returns {string}
*/
static formatRight(value, logic, exclusive) {
if (logic === false) {
return Range.formatLeft(value, !logic, !exclusive);
}
return `should be ${Range.getOperator("right", exclusive)} ${value}`;
}
/**
* @param {number} value
* @param {boolean} logic is not logic applied
* @param {boolean} exclusive is range exclusive
* @returns {string}
*/
static formatLeft(value, logic, exclusive) {
if (logic === false) {
return Range.formatRight(value, !logic, !exclusive);
}
return `should be ${Range.getOperator("left", exclusive)} ${value}`;
}
/**
* @param {number} start left side value
* @param {number} end right side value
* @param {boolean} startExclusive is range exclusive from left side
* @param {boolean} endExclusive is range exclusive from right side
* @param {boolean} logic is not logic applied
* @returns {string}
*/
static formatRange(start, end, startExclusive, endExclusive, logic) {
let result = "should be";
result += ` ${Range.getOperator(logic ? "left" : "right", logic ? startExclusive : !startExclusive)} ${start} `;
result += logic ? "and" : "or";
result += ` ${Range.getOperator(logic ? "right" : "left", logic ? endExclusive : !endExclusive)} ${end}`;
return result;
}
/**
* @param {Array<RangeValue>} values
* @param {boolean} logic is not logic applied
* @return {RangeValue} computed value and it's exclusive flag
*/
static getRangeValue(values, logic) {
let minMax = logic ? Infinity : -Infinity;
let j = -1;
const predicate = logic ?
/** @type {RangeValueCallback} */
([value]) => value <= minMax :
/** @type {RangeValueCallback} */
([value]) => value >= minMax;
for (let i = 0; i < values.length; i++) {
if (predicate(values[i])) {
[minMax] = values[i];
j = i;
}
}
if (j > -1) {
return values[j];
}
return [Infinity, true];
}
constructor() {
/** @type {Array<RangeValue>} */
this._left = [];
/** @type {Array<RangeValue>} */
this._right = [];
}
/**
* @param {number} value
* @param {boolean=} exclusive
*/
left(value, exclusive = false) {
this._left.push([value, exclusive]);
}
/**
* @param {number} value
* @param {boolean=} exclusive
*/
right(value, exclusive = false) {
this._right.push([value, exclusive]);
}
/**
* @param {boolean} logic is not logic applied
* @return {string} "smart" range string representation
*/
format(logic = true) {
const [start, leftExclusive] = Range.getRangeValue(this._left, logic);
const [end, rightExclusive] = Range.getRangeValue(this._right, !logic);
if (!Number.isFinite(start) && !Number.isFinite(end)) {
return "";
}
const realStart = leftExclusive ? start + 1 : start;
const realEnd = rightExclusive ? end - 1 : end; // e.g. 5 < x < 7, 5 < x <= 6, 6 <= x <= 6
if (realStart === realEnd) {
return `should be ${logic ? "" : "!"}= ${realStart}`;
} // e.g. 4 < x < ∞
if (Number.isFinite(start) && !Number.isFinite(end)) {
return Range.formatLeft(start, logic, leftExclusive);
} // e.g. ∞ < x < 4
if (!Number.isFinite(start) && Number.isFinite(end)) {
return Range.formatRight(end, logic, rightExclusive);
}
return Range.formatRange(start, end, leftExclusive, rightExclusive, logic);
}
}
module.exports = Range;