"use strict";

const timeCall = require("time-call");
const syncpipe = require("syncpipe");

// let list1 = [ 2, 9, 10, 12, 13, 16, 19, 21, 23, 24, 33, 43, 46, 48, 49, 58, 60, 61, 69, 71, 74, 75, 78, 79, 80, 82, 85, 86, 88, 90, 91, 92, 95, 98, 99 ];
// let list2 = [ 3, 4, 5, 9, 10, 12, 13, 14, 16, 17, 19, 23, 24, 28, 29, 31, 32, 34, 37, 41, 42, 44, 45, 48, 50, 51, 52, 55, 56, 64, 69, 75, 77, 79, 85, 87, 91, 92, 93, 94, 98 ];
// let list3 = [ 2, 5, 8, 9, 15, 23, 27, 31, 32, 33, 34, 36, 37, 40, 43, 45, 53, 54, 56, 58, 60, 63, 64, 66, 71, 72, 74, 75, 78, 84, 89, 91, 94, 96, 97, 98, 99 ];

function randomIntegers(count, limit) {
	return syncpipe(new Array(count), [
		_ => _.fill(0),
		_ => _.map(() => Math.ceil(Math.random() * limit)),
		_ => new Set(_),
		_ => Array.from(_),
		_ => _.sort((a, b) => a - b)
	]);
}

let list1 = randomIntegers(1000, 2000);
let list2 = randomIntegers(1000, 2000);
let list3 = randomIntegers(1000, 2000);

console.log(list1);

function intersectThree(list1, list2, list3) {
	let pointer1 = 0;
	let pointer2 = 0;
	let pointer3 = 0;

	let results = [];

	while (pointer1 < list1.length && pointer2 < list2.length && pointer3 < list3.length) {
		let value1 = list1[pointer1];
		let value2 = list2[pointer2];
		let value3 = list3[pointer3];

		if (value1 === value2 && value1 === value3) {
			results.push(value1);

			pointer1++;
			pointer2++;
			pointer3++;
		} else {
			let lowest = Math.min(value1, value2, value3);

			if (value1 === lowest) { pointer1++; }
			if (value2 === lowest) { pointer2++; }
			if (value3 === lowest) { pointer3++; }
		}
	}

	return results;
}

function intersectSets(list1, list2, list3) {
	let set2 = new Set(list2);
	let set3 = new Set(list3);

	return list1.filter((value) => set2.has(value) && set3.has(value));
}

function intersectSets2(list1, list2, list3) {
	let set2 = new Set(list2);
	let set3 = new Set(list3);

	let results = [];

	for (let value of list1) {
		if (set2.has(value) && set3.has(value)) {
			results.push(value);
		}
	}
	
	return results;
}

function tryOut(ITERATIONS) {
	console.log(`# ${ITERATIONS} iterations, time is per iteration`);

	let result1 = timeCall(() => {
		for (let i = 0; i < ITERATIONS; i++) {
			intersectThree(list1, list2, list3);
		}
	});
	
	let result2 = timeCall(() => {
		for (let i = 0; i < ITERATIONS; i++) {
			intersectSets(list1, list2, list3);
		}
	});
	
	let result3 = timeCall(() => {
		for (let i = 0; i < ITERATIONS; i++) {
			intersectSets2(list1, list2, list3);
		}
	});
	
	console.log({
		pointer: result1.time / ITERATIONS / 1e3 + "us",
		setsFilter: result2.time / ITERATIONS / 1e3 + "us",
		setsFor: result3.time / ITERATIONS / 1e3 + "us"
	});
}

tryOut(100);
tryOut(1000);
tryOut(10000);
tryOut(100000);


// console.log(intersectThree(list1, list2, list3));