zater-verhoeff/src/Verhoeff.js

Module for create account zater

class Verhoeff {
	constructor(array) {
		this.d = [
			[0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
			[1, 2, 3, 4, 0, 6, 7, 8, 9, 5],
			[2, 3, 4, 0, 1, 7, 8, 9, 5, 6],
			[3, 4, 0, 1, 2, 8, 9, 5, 6, 7],
			[4, 0, 1, 2, 3, 9, 5, 6, 7, 8],
			[5, 9, 8, 7, 6, 0, 4, 3, 2, 1],
			[6, 5, 9, 8, 7, 1, 0, 4, 3, 2],
			[7, 6, 5, 9, 8, 2, 1, 0, 4, 3],
			[8, 7, 6, 5, 9, 3, 2, 1, 0, 4],
			[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
		];
		// permutation table p
		this.p = [
			[0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
			[1, 5, 7, 6, 2, 8, 3, 0, 9, 4],
			[5, 8, 0, 3, 7, 9, 6, 1, 4, 2],
			[8, 9, 1, 6, 0, 4, 3, 5, 2, 7],
			[9, 4, 5, 3, 1, 2, 6, 8, 7, 0],
			[4, 2, 8, 6, 5, 7, 3, 9, 0, 1],
			[2, 7, 9, 3, 8, 0, 6, 4, 1, 5],
			[7, 0, 4, 6, 9, 1, 3, 2, 5, 8]
		];
		// inverse table inv
		this.inv = [0, 4, 3, 2, 1, 5, 6, 7, 8, 9];
		this.array = array;
	}

	invArray() {
		let array = this.array;
		if (Object.prototype.toString.call(array) === "[object Number]") {
			array = String(array);
		}
		if (Object.prototype.toString.call(array) === "[object String]") {
			array = array.split("").map(Number);
		}
		return array
	}

	generate() {
		let c = 0;
		const invertedArray = this.invArray(this.array);
		for (let i = 0; i < invertedArray.length; i++) {
			c = this.d[c][this.p[((i + 1) % 8)][invertedArray[i]]];
		}
		return this.inv[c];
	}

	validate(verify) {
		let c = 0;
		const invertedArray = this.invArray(`${this.array}${verify}`);
		for (let i = 0; i < invertedArray.length; i++) {
			c = this.d[c][this.p[(i % 8)][invertedArray[i]]];
		}
		return (c === 0);
	}
}

export default  (array) => new Verhoeff(array);