/*
 * decaffeinate suggestions:
 * DS101: Remove unnecessary use of Array.from
 * DS102: Remove unnecessary code created because of implicit returns
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
const async = require("async");
const {expect} = require("chai");

const RealTimeClient = require("./helpers/RealTimeClient");
const MockDocUpdaterServer = require("./helpers/MockDocUpdaterServer");
const MockWebServer = require("./helpers/MockWebServer");
const FixturesManager = require("./helpers/FixturesManager");

const settings = require("settings-sharelatex");
const redis = require("redis-sharelatex");
const rclient = redis.createClient(settings.redis.pubsub);
const rclientRT = redis.createClient(settings.redis.realtime);
const KeysRT = settings.redis.realtime.key_schema;

describe("EarlyDisconnect", function() {
	before(done => MockDocUpdaterServer.run(done));

	describe("when the client disconnects before joinProject completes", function() {
		before(function() {
			// slow down web-api requests to force the race condition
			let joinProject;
			this.actualWebAPIjoinProject = (joinProject = MockWebServer.joinProject);
			return MockWebServer.joinProject = (project_id, user_id, cb) => setTimeout(() => joinProject(project_id, user_id, cb)
            , 300);
		});

		after(function() {
			return MockWebServer.joinProject = this.actualWebAPIjoinProject;
		});

		beforeEach(function(done) {
			return async.series([
				cb => {
					return FixturesManager.setUpProject({
						privilegeLevel: "owner",
						project: {
							name: "Test Project"
						}
					}, (e, {project_id, user_id}) => { this.project_id = project_id; this.user_id = user_id; return cb(); });
				},

				cb => {
					this.clientA = RealTimeClient.connect();
					return this.clientA.on("connectionAccepted", cb);
				},

				cb => {
					this.clientA.emit("joinProject", {project_id: this.project_id}, (function() {}));
					// disconnect before joinProject completes
					this.clientA.on("disconnect", () => cb());
					return this.clientA.disconnect();
				},

				cb => {
					// wait for joinDoc and subscribe
					return setTimeout(cb, 500);
				}
			], done);
		});

		// we can force the race condition, there is no need to repeat too often
		return Array.from(Array.from({length: 5}).map((_, i) => i+1)).map((attempt) =>
			it(`should not subscribe to the pub/sub channel anymore (race ${attempt})`, function(done) {
				rclient.pubsub('CHANNELS', (err, resp) => {
					if (err) { return done(err); }
					expect(resp).to.not.include(`editor-events:${this.project_id}`);
					return done();
				});
				return null;
			}));
	});

	describe("when the client disconnects before joinDoc completes", function() {
		beforeEach(function(done) {
			return async.series([
				cb => {
					return FixturesManager.setUpProject({
						privilegeLevel: "owner",
						project: {
							name: "Test Project"
						}
					}, (e, {project_id, user_id}) => { this.project_id = project_id; this.user_id = user_id; return cb(); });
				},

				cb => {
					this.clientA = RealTimeClient.connect();
					return this.clientA.on("connectionAccepted", cb);
				},

				cb => {
					return this.clientA.emit("joinProject", {project_id: this.project_id}, (error, project, privilegeLevel, protocolVersion) => {
						this.project = project;
						this.privilegeLevel = privilegeLevel;
						this.protocolVersion = protocolVersion;
						return cb(error);
					});
				},

				cb => {
					return FixturesManager.setUpDoc(this.project_id, {lines: this.lines, version: this.version, ops: this.ops}, (e, {doc_id}) => {
						this.doc_id = doc_id;
						return cb(e);
					});
				},

				cb => {
					this.clientA.emit("joinDoc", this.doc_id, (function() {}));
					// disconnect before joinDoc completes
					this.clientA.on("disconnect", () => cb());
					return this.clientA.disconnect();
				},

				cb => {
					// wait for subscribe and unsubscribe
					return setTimeout(cb, 100);
				}
			], done);
		});

		// we can not force the race condition, so we have to try many times
		return Array.from(Array.from({length: 20}).map((_, i) => i+1)).map((attempt) =>
			it(`should not subscribe to the pub/sub channels anymore (race ${attempt})`, function(done) {
				rclient.pubsub('CHANNELS', (err, resp) => {
					if (err) { return done(err); }
					expect(resp).to.not.include(`editor-events:${this.project_id}`);

					return rclient.pubsub('CHANNELS', (err, resp) => {
						if (err) { return done(err); }
						expect(resp).to.not.include(`applied-ops:${this.doc_id}`);
						return done();
					});
				});
				return null;
			}));
	});

	return describe("when the client disconnects before clientTracking.updatePosition starts", function() {
		beforeEach(function(done) {
			return async.series([
				cb => {
					return FixturesManager.setUpProject({
						privilegeLevel: "owner",
						project: {
							name: "Test Project"
						}
					}, (e, {project_id, user_id}) => { this.project_id = project_id; this.user_id = user_id; return cb(); });
				},

				cb => {
					this.clientA = RealTimeClient.connect();
					return this.clientA.on("connectionAccepted", cb);
				},

				cb => {
					return this.clientA.emit("joinProject", {project_id: this.project_id}, (error, project, privilegeLevel, protocolVersion) => {
						this.project = project;
						this.privilegeLevel = privilegeLevel;
						this.protocolVersion = protocolVersion;
						return cb(error);
					});
				},

				cb => {
					return FixturesManager.setUpDoc(this.project_id, {lines: this.lines, version: this.version, ops: this.ops}, (e, {doc_id}) => {
						this.doc_id = doc_id;
						return cb(e);
					});
				},

				cb => {
					return this.clientA.emit("joinDoc", this.doc_id, cb);
				},

				cb => {
					this.clientA.emit("clientTracking.updatePosition", {
							row: 42,
							column: 36,
							doc_id: this.doc_id
						}, (function() {}));
					// disconnect before updateClientPosition completes
					this.clientA.on("disconnect", () => cb());
					return this.clientA.disconnect();
				},

				cb => {
					// wait for updateClientPosition
					return setTimeout(cb, 100);
				}
			], done);
		});

		// we can not force the race condition, so we have to try many times
		return Array.from(Array.from({length: 20}).map((_, i) => i+1)).map((attempt) =>
			it(`should not show the client as connected (race ${attempt})`, function(done) {
				rclientRT.smembers(KeysRT.clientsInProject({project_id: this.project_id}), function(err, results) {
					if (err) { return done(err); }
					expect(results).to.deep.equal([]);
					return done();
				});
				return null;
			}));
	});
});