/* eslint-disable no-sparse-arrays */
import { Queue } from "../../src/flowcontrol/Queue";
import { expect } from "chai";

describe("Queue", () => {
    it("empty returns undefined", () => {
        const sut = new Queue(4);
        expect(sut.shift()).to.be.undefined;
    });

    it("pushes and shifts", () => {
        const sut = new Queue(4);
        sut.push(0);
        sut.push(1);
        expect(sut.shift()).to.equal(0);
        expect(sut.shift()).to.equal(1);
    });

    it("pushes and shifts without resize", () => {
        const sut = new Queue(4);
        sut.push(0);
        sut.push(1);
        sut.push(2);
        expect(sut.buffer.buffer).to.deep.equal([undefined, 0, 1, 2]);
        expect(sut.shift()).to.equal(0);
        expect(sut.shift()).to.equal(1);
        expect(sut.shift()).to.equal(2);
    });

    for (let iter = 0; iter < 3; iter++) {
        it(`resize iteration ${iter}`, () => {
            const sut = new Queue(4);
            for (let i = 0; i < iter; i++) {
                sut.push(0);
                sut.shift();
            }

            sut.push(1);
            sut.push(2);
            sut.push(3);
            sut.push(4); // causes resize

            expect(sut.buffer.buffer).to.deep.equal([
                undefined,
                1,
                2,
                3,
                4,
                undefined,
                undefined,
                undefined,
            ]);
        });
    }

    it("resize many", () => {
        const sut = new Queue(2);
        for (let i = 0; i < 1024; i++) {
            sut.push(i);
        }
        for (let i = 0; i < 1024; i++) {
            expect(sut.shift()).to.equal(i);
        }
    });
});