apiStore.js

var EventEmitter = require('events');
var AddonCollection = require('stremio-addon-client').AddonCollection;
var mapURL = require('stremio-addon-client').mapURL;
var officialAddons = require('stremio-official-addons');
var MemoryStorage = require('./lib/memoryStorage');
var addonsDifferent = require('./lib/addonsDifferent');
var ApiClient = require('./apiClient');

var ENDPOINT = 'https://api.strem.io';
var INTERRUPTED_ERROR_MESSAGE = 'request interrupted';

var USER_REQUIRED = 'user required to invoke this';

function ApiStore(options) {
	options = options || {};
	var endpoint = options.endpoint || ENDPOINT;
	var storage = options.storage || new MemoryStorage();
	var client = new ApiClient({ endpoint: endpoint, authKey: storage.getJSON('authKey') });

	var self = this;

	this.endpoint = endpoint;

	this.events = new EventEmitter();

	this.user = storage.getJSON('user');
	// Migration from legacy format
	if (this.user && this.user.authKey) {
		storage.setJSON('authKey', this.user.authKey);
		client = new ApiClient({ endpoint: endpoint, authKey: this.user.authKey });
		storage.setJSON('user', this.user);
	}

	this.addons = new AddonCollection();
	this.addons.load(storage.getJSON('addons') || officialAddons);

	this.request = function(method, params) {
		var currentClient = client;
		return new Promise(function(resolve, reject) {
			currentClient.request(method, params)
				.then(function(resp) {
					if (currentClient !== client) {
						reject(new Error(INTERRUPTED_ERROR_MESSAGE));
						return;
					}

					resolve(resp);
				})
				.catch(function(err) {
					if (currentClient !== client) {
						reject(new Error(INTERRUPTED_ERROR_MESSAGE));
						return;
					}

					reject(err);
				});
		});
	};

	this.login = function(params) {
		return this.request('login', params)
			.then(function(result) {
				self.userChange(result.authKey, result.user);
				addonsUpdated(null, null);
			});
	};

	this.loginWithToken = function(params) {
		return this.request('loginWithToken', params)
			.then(function(result) {
				self.userChange(result.authKey, result.user);
				addonsUpdated(null, null);
			});
	};

	this.authWithApple = function(params) {
		return this.request('authWithApple', params)
			.then(function(result) {
				self.userChange(result.authKey, result.user);
				addonsUpdated(null, null);
			});
	};

	this.register = function(params) {
		return this.request('register', params)
			.then(function(result) {
				self.userChange(result.authKey, result.user);
				addonsUpdated(null, null);
			});
	};

	this.logout = function() {
		return this.request('logout')
			.then(function() {
				self.userChange(null, null);
				addonsUpdated(null, null);
			})
			.catch(function(err) {
				if (err && err.message === INTERRUPTED_ERROR_MESSAGE) {
					throw err;
				}

				self.userChange(null, null);
				addonsUpdated(null, null);
			});
	};

	//
	// pullAddonCollection, pushAddonCollection
	//
	this.pullAddonCollection = function() {
		if (!self.user) {
			return Promise.reject(new Error(USER_REQUIRED));
		}

		var params = { update: true, addFromURL: [] };

		var legacyKey = 'addons:' + (self.user ? self.user._id : '');
		params.addFromURL = mapLegacyAddonRepo(storage.getJSON(legacyKey));

		var lastModifiedOriginal = storage.getJSON('addonsLastModified') || 0;

		return this.request('addonCollectionGet', params)
			.then(function(resp) {
				if (!Array.isArray(resp.addons)) {
					throw 'no resp.addons';
				}

				var lastModified = storage.getJSON('addonsLastModified') || 0;
				var newLastModified = new Date(resp.lastModified).getTime();
				if (resp.addons.length && lastModified == lastModifiedOriginal && newLastModified > lastModified) {
					addonsUpdated(resp.addons, newLastModified);

					if (params.addFromURL.length) {
						storage.setJSON(legacyKey, null);
					}
				}
			});
	};

	this.pushAddonCollection = function() {
		var descriptors = self.addons.save();
		storage.setJSON('addons', descriptors);
		storage.setJSON('addonsLastModified', Date.now());

		if (!self.user) {
			return Promise.resolve();
		}

		return self.request('addonCollectionSet', { addons: descriptors });
	};

	//
	// pullUser, pushUser
	//
	this.pullUser = function() {
		if (!self.user) {
			return Promise.reject(new Error(USER_REQUIRED));
		}

		return this.request('getUser')
			.then(function(user) {
				if (!(user && user._id)) {
					throw 'invalid user returned';
				}

				var lastModified = new Date(self.user.lastModified).getTime();
				var newLastModified = new Date(user.lastModified).getTime();
				if (newLastModified > lastModified) {
					storage.setJSON('user', user);
					self.user = user;
				}
			});
	};

	this.pushUser = function() {
		if (!self.user) {
			return Promise.reject(new Error(USER_REQUIRED));
		}

		self.user.lastModified = new Date();
		storage.setJSON('user', self.user);
		return self.request('saveUser', self.user);
	};

	//
	// Private methods
	//

	// only invoked when the user is changed by _id (different user)
	// call this with (null, null) when logging out
	this.userChange = function(authKey, user) {
		storage.setJSON('authKey', authKey);
		storage.setJSON('user', user);
		client = new ApiClient({ endpoint: endpoint, authKey: authKey });
		self.user = user;
		self.events.emit('user-change', user);
	};

	// this may be invoked when the add-on set is updated
	function addonsUpdated(descriptors, lastModified) {
		var isDifferent = addonsDifferent(descriptors || [], self.addons.getAddons());

		storage.setJSON('addons', descriptors);
		storage.setJSON('addonsLastModified', lastModified || 0);
		self.addons.load(descriptors || officialAddons);
		self.events.emit('addons-change');
		if (isDifferent) self.events.emit('addons-different');
	}

	// remaps old add-on format into a list of URLs
	function mapLegacyAddonRepo(repo) {
		if (repo && Array.isArray(repo.addons)) {
			return repo.addons
				.filter(function(x) { return Array.isArray(x.endpoints) && typeof (x.endpoints[0]) === 'string'; })
				.map(function(x) { return mapURL(x.endpoints[0]); });
		}
		return [];
	}

	Object.seal(this);
	return this;
}

module.exports = ApiStore;