/*
 * decaffeinate suggestions:
 * DS102: Remove unnecessary code created because of implicit returns
 * DS206: Consider reworking classes to avoid initClass
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
const sinon = require('sinon');
const chai = require('chai');
const should = chai.should();
const {
    expect
} = chai;
const modulePath = "../../../../app/js/RateLimitManager.js";
const SandboxedModule = require('sandboxed-module');

describe("RateLimitManager", function() {
	beforeEach(function() {
		let Timer;
		this.RateLimitManager = SandboxedModule.require(modulePath, { requires: {
			"logger-sharelatex": (this.logger = { log: sinon.stub() }),
			"settings-sharelatex": (this.settings = {}),
			"./Metrics": (this.Metrics = {
				Timer: (Timer = (function() {
					Timer = class Timer {
						static initClass() {
							this.prototype.done = sinon.stub();
						}
					};
					Timer.initClass();
					return Timer;
				})()),
				gauge: sinon.stub()
			})
		}
	}
		);
		this.callback = sinon.stub();
		return this.RateLimiter = new this.RateLimitManager(1);
	});

	describe("for a single task", function() {
		beforeEach(function() {
			this.task = sinon.stub();
			return this.RateLimiter.run(this.task, this.callback);
		});

		it("should execute the task in the background", function() {
			return this.task.called.should.equal(true);
		});

		it("should call the callback", function() {
			return this.callback.called.should.equal(true);
		});

		return it("should finish with a worker count of one", function() {
			// because it's in the background
			return expect(this.RateLimiter.ActiveWorkerCount).to.equal(1);
		});
	});

	describe("for multiple tasks", function() {
		beforeEach(function(done) {
			this.task = sinon.stub();
			this.finalTask = sinon.stub();
			const task = cb => {
				this.task();
				return setTimeout(cb, 100);
			};
			const finalTask = cb => {
				this.finalTask();
				return setTimeout(cb, 100);
			};
			this.RateLimiter.run(task, this.callback);
			this.RateLimiter.run(task, this.callback);
			this.RateLimiter.run(task, this.callback);
			return this.RateLimiter.run(finalTask, err => {
				this.callback(err);
				return done();
			});
		});

		it("should execute the first three tasks", function() {
			return this.task.calledThrice.should.equal(true);
		});

		it("should execute the final task", function() {
			return this.finalTask.called.should.equal(true);
		});

		it("should call the callback", function() {
			return this.callback.called.should.equal(true);
		});

		return it("should finish with worker count of zero", function() {
			return expect(this.RateLimiter.ActiveWorkerCount).to.equal(0);
		});
	});

	return describe("for a mixture of long-running tasks", function() {
		beforeEach(function(done) {
			this.task = sinon.stub();
			this.finalTask = sinon.stub();
			const finalTask = cb => {
				this.finalTask();
				return setTimeout(cb, 100);
			};
			this.RateLimiter.run(this.task, this.callback);
			this.RateLimiter.run(this.task, this.callback);
			this.RateLimiter.run(this.task, this.callback);
			return this.RateLimiter.run(finalTask, err => {
				this.callback(err);
				return done();
			});
		});

		it("should execute the first three tasks", function() {
			return this.task.calledThrice.should.equal(true);
		});

		it("should execute the final task", function() {
			return this.finalTask.called.should.equal(true);
		});

		it("should call the callback", function() {
			return this.callback.called.should.equal(true);
		});

		return it("should finish with worker count of three", function() {
			return expect(this.RateLimiter.ActiveWorkerCount).to.equal(3);
		});
	});
});