mail/test/new-unit/email-dao-test.js

define(function(require) {
    'use strict';

    var EmailDAO = require('js/dao/email-dao'),
        KeychainDAO = require('js/dao/keychain-dao'),
        ImapClient = require('imap-client'),
        PgpMailer = require('pgpmailer'),
        PGP = require('js/crypto/pgp'),
        DeviceStorageDAO = require('js/dao/devicestorage-dao'),
        str = require('js/app-config').string,
        expect = chai.expect;


    describe('Email DAO unit tests', function() {
        var dao, keychainStub, imapClientStub, pgpMailerStub, pgpStub, devicestorageStub;

        var emailAddress, passphrase, asymKeySize, mockkeyId, dummyEncryptedMail,
            dummyDecryptedMail, dummyLegacyDecryptedMail, mockKeyPair, account, publicKey, verificationMail, verificationUuid,
            corruptedVerificationMail, corruptedVerificationUuid,
            nonWhitelistedMail;

        beforeEach(function(done) {
            emailAddress = 'asdf@asdf.com';
            passphrase = 'asdf';
            asymKeySize = 2048;
            mockkeyId = 1234;
            dummyEncryptedMail = {
                uid: 1234,
                from: [{
                    address: 'asd@asd.de'
                }],
                to: [{
                    address: 'qwe@qwe.de'
                }],
                subject: '[whiteout] qweasd',
                body: '-----BEGIN PGP MESSAGE-----\nasd\n-----END PGP MESSAGE-----',
                unread: false,
                answered: false
            };
            verificationUuid = '9A858952-17EE-4273-9E74-D309EAFDFAFB';
            verificationMail = {
                from: [{
                    name: 'Whiteout Test',
                    address: 'whiteout.test@t-online.de'
                }], // sender address
                to: [{
                    address: 'safewithme.testuser@gmail.com'
                }], // list of receivers
                subject: "[whiteout] New public key uploaded", // Subject line
                body: 'yadda yadda bla blabla foo bar https://keys.whiteout.io/verify/' + verificationUuid, // plaintext body
                unread: true,
                answered: false
            };
            corruptedVerificationUuid = 'OMFG_FUCKING_BASTARD_UUID_FROM_HELL!';
            corruptedVerificationMail = {
                from: [{
                    name: 'Whiteout Test',
                    address: 'whiteout.test@t-online.de'
                }], // sender address
                to: [{
                    address: 'safewithme.testuser@gmail.com'
                }], // list of receivers
                subject: "[whiteout] New public key uploaded", // Subject line
                body: 'yadda yadda bla blabla foo bar https://keys.whiteout.io/verify/' + corruptedVerificationUuid, // plaintext body
                unread: true,
                answered: false
            };
            dummyDecryptedMail = {
                uid: 1234,
                from: [{
                    address: 'asd@asd.de'
                }],
                to: [{
                    address: 'qwe@qwe.de'
                }],
                subject: 'qweasd',
                body: 'Content-Type: multipart/signed;\r\n  boundary="Apple-Mail=_1D8756C0-F347-4D7A-A8DB-7869CBF14FD2";\r\n    protocol="application/pgp-signature";\r\n   micalg=pgp-sha512\r\n\r\n\r\n--Apple-Mail=_1D8756C0-F347-4D7A-A8DB-7869CBF14FD2\r\nContent-Type: multipart/mixed;\r\n   boundary="Apple-Mail=_8ED7DC84-6AD9-4A08-8327-80B62D6BCBFA"\r\n\r\n\r\n--Apple-Mail=_8ED7DC84-6AD9-4A08-8327-80B62D6BCBFA\r\nContent-Transfer-Encoding: 7bit\r\nContent-Type: text/plain;\r\n   charset=us-ascii\r\n\r\nasdasd \r\n--Apple-Mail=_8ED7DC84-6AD9-4A08-8327-80B62D6BCBFA\r\nContent-Disposition: attachment;\r\n   filename=dummy.txt\r\nContent-Type: text/plain;\r\n name="dummy.txt"\r\nContent-Transfer-Encoding: 7bit\r\n\r\noaudbcoaurbvosuabvlasdjbfalwubjvawvb\r\n--Apple-Mail=_8ED7DC84-6AD9-4A08-8327-80B62D6BCBFA--\r\n\r\n--Apple-Mail=_1D8756C0-F347-4D7A-A8DB-7869CBF14FD2\r\nContent-Transfer-Encoding: 7bit\r\nContent-Disposition: attachment;\r\n    filename=signature.asc\r\nContent-Type: application/pgp-signature;\r\n  name=signature.asc\r\nContent-Description: Message signed with OpenPGP using GPGMail\r\n\r\n-----BEGIN PGP SIGNATURE-----\r\nComment: GPGTools - https://gpgtools.org\r\n\r\niQEcBAEBCgAGBQJS2kO1AAoJEDzmUwH7XO/cP+YH/2PSBxX1ZZd83Uf9qBGDY807\r\niHOdgPFXm64YjSnohO7XsPcnmihqP1ipS2aaCXFC3/Vgb9nc4isQFS+i1VdPwfuR\r\n1Pd2l3dC4/nD4xO9h/W6JW7Yd24NS5TJD5cA7LYwQ8LF+rOzByMatiTMmecAUCe8\r\nEEalEjuogojk4IacA8dg/bfLqQu9E+0GYUJBcI97dx/0jZ0qMOxbWOQLsJ3DnUnV\r\nOad7pAIbHEO6T0EBsH7TyTj4RRHkP6SKE0mm6ZYUC7KCk2Z3MtkASTxUrnqW5qZ5\r\noaXUO9GEc8KZcmbCdhZY2Y5h+dmucaO0jpbeSKkvtYyD4KZrSvt7NTb/0dSLh4Y=\r\n=G8km\r\n-----END PGP SIGNATURE-----\r\n\r\n--Apple-Mail=_1D8756C0-F347-4D7A-A8DB-7869CBF14FD2--\r\n',
                unread: false,
                answered: false,
                receiverKeys: ['-----BEGIN PGP PUBLIC KEY-----\nasd\n-----END PGP PUBLIC KEY-----']
            };
            dummyLegacyDecryptedMail = {
                uid: 1234,
                from: [{
                    address: 'asd@asd.de'
                }],
                to: [{
                    address: 'qwe@qwe.de'
                }],
                subject: 'qweasd',
                body: 'asd',
                unread: false,
                answered: false,
                receiverKeys: ['-----BEGIN PGP PUBLIC KEY-----\nasd\n-----END PGP PUBLIC KEY-----']
            };
            nonWhitelistedMail = {
                uid: 1234,
                from: [{
                    address: 'asd@asd.de'
                }],
                to: [{
                    address: 'qwe@qwe.de'
                }],
                subject: 'qweasd',
                body: 'asd'
            };
            mockKeyPair = {
                publicKey: {
                    _id: mockkeyId,
                    userId: emailAddress,
                    publicKey: 'publicpublicpublicpublic'
                },
                privateKey: {
                    _id: mockkeyId,
                    userId: emailAddress,
                    encryptedKey: 'privateprivateprivateprivate'
                }
            };
            account = {
                emailAddress: emailAddress,
                asymKeySize: asymKeySize,
                busy: false
            };
            publicKey = "-----BEGIN PUBLIC KEY-----\r\n" + "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCxy+Te5dyeWd7g0P+8LNO7fZDQ\r\n" + "g96xTb1J6pYE/pPTMlqhB6BRItIYjZ1US5q2vk5Zk/5KasBHAc9RbCqvh9v4XFEY\r\n" + "JVmTXC4p8ft1LYuNWIaDk+R3dyYXmRNct/JC4tks2+8fD3aOvpt0WNn3R75/FGBt\r\n" + "h4BgojAXDE+PRQtcVQIDAQAB\r\n" + "-----END PUBLIC KEY-----";

            keychainStub = sinon.createStubInstance(KeychainDAO);
            imapClientStub = sinon.createStubInstance(ImapClient);
            pgpMailerStub = sinon.createStubInstance(PgpMailer);
            pgpStub = sinon.createStubInstance(PGP);
            devicestorageStub = sinon.createStubInstance(DeviceStorageDAO);

            dao = new EmailDAO(keychainStub, pgpStub, devicestorageStub);
            dao._account = account;

            expect(dao._keychain).to.equal(keychainStub);
            expect(dao._crypto).to.equal(pgpStub);
            expect(dao._devicestorage).to.equal(devicestorageStub);

            // connect
            expect(dao._imapClient).to.not.exist;
            expect(dao._smtpClient).to.not.exist;
            expect(dao._account.online).to.be.undefined;
            dao._account.folders = [];
            imapClientStub.login.yields();

            dao.onConnect({
                imapClient: imapClientStub,
                pgpMailer: pgpMailerStub
            }, function(err) {
                expect(err).to.not.exist;
                expect(dao._account.online).to.be.true;
                expect(dao._imapClient).to.equal(dao._imapClient);
                expect(dao._smtpClient).to.equal(dao._smtpClient);
                done();
            });
        });

        afterEach(function(done) {
            dao.onDisconnect(null, function(err) {
                expect(err).to.not.exist;
                expect(dao._account.online).to.be.false;
                expect(dao._imapClient).to.not.exist;
                expect(dao._smtpClient).to.not.exist;
                done();
            });
        });

        describe('push', function() {
            it('should work', function(done) {
                var o = {};

                dao.onIncomingMessage = function(obj) {
                    expect(obj).to.equal(o);
                    done();
                };

                dao._imapClient.onIncomingMessage(o);
            });
        });

        describe('init', function() {
            beforeEach(function() {
                delete dao._account;
            });

            it('should init', function(done) {
                var listFolderStub, folders;

                folders = [{}, {}];

                // initKeychain
                devicestorageStub.init.withArgs(emailAddress).yields();
                keychainStub.getUserKeyPair.yields(null, mockKeyPair);

                // initFolders
                listFolderStub = sinon.stub(dao, '_imapListFolders');
                listFolderStub.yields(null, folders);

                dao.init({
                    account: account
                }, function(err, keyPair) {
                    expect(err).to.not.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.online).to.be.false;
                    expect(keyPair).to.equal(mockKeyPair);

                    expect(dao._account).to.equal(account);
                    expect(dao._account.folders).to.equal(folders);
                    expect(devicestorageStub.init.calledOnce).to.be.true;
                    expect(keychainStub.getUserKeyPair.calledOnce).to.be.true;

                    expect(listFolderStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should not fail when offline', function(done) {
                var listFolderStub;

                // initKeychain
                devicestorageStub.init.withArgs(emailAddress).yields();
                keychainStub.getUserKeyPair.yields(null, mockKeyPair);

                // initFolders
                listFolderStub = sinon.stub(dao, '_imapListFolders');
                listFolderStub.yields({
                    code: 42
                });

                dao.init({
                    account: account
                }, function(err, keyPair) {
                    expect(err).to.not.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.online).to.be.false;
                    expect(keyPair).to.equal(mockKeyPair);

                    expect(dao._account).to.equal(account);
                    expect(dao._account.folders).to.equal(undefined);
                    expect(devicestorageStub.init.calledOnce).to.be.true;
                    expect(keychainStub.getUserKeyPair.calledOnce).to.be.true;
                    expect(listFolderStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail due to error while listing folders', function(done) {
                var listFolderStub;

                // initKeychain
                devicestorageStub.init.withArgs(emailAddress).yields();
                keychainStub.getUserKeyPair.yields(null, mockKeyPair);

                // initFolders
                listFolderStub = sinon.stub(dao, '_imapListFolders');
                listFolderStub.yields({});

                dao.init({
                    account: account
                }, function(err, keyPair) {
                    expect(err).to.exist;
                    expect(keyPair).to.not.exist;

                    expect(dao._account).to.equal(account);
                    expect(devicestorageStub.init.calledOnce).to.be.true;
                    expect(keychainStub.getUserKeyPair.calledOnce).to.be.true;
                    expect(listFolderStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail due to error in getUserKeyPair', function(done) {
                devicestorageStub.init.yields();
                keychainStub.getUserKeyPair.yields({});

                dao.init({
                    account: account
                }, function(err, keyPair) {
                    expect(err).to.exist;
                    expect(keyPair).to.not.exist;

                    expect(devicestorageStub.init.calledOnce).to.be.true;

                    done();
                });
            });
        });

        describe('onConnect', function() {
            var imapLoginStub, imapListFoldersStub, pgpmailerLoginStub;

            beforeEach(function(done) {
                // imap login
                imapLoginStub = sinon.stub(dao, '_imapLogin');
                pgpmailerLoginStub = sinon.stub(dao, '_pgpmailerLogin');
                imapListFoldersStub = sinon.stub(dao, '_imapListFolders');

                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;
                    expect(dao._imapClient).to.not.exist;
                    expect(dao._smtpClient).to.not.exist;
                    expect(dao._account.online).to.be.false;
                    done();
                });
            });

            afterEach(function() {
                imapLoginStub.restore();
                pgpmailerLoginStub.restore();
                imapListFoldersStub.restore();
            });

            it('should fail due to error in imap login', function(done) {
                imapLoginStub.yields({});
                pgpmailerLoginStub.returns();

                dao.onConnect({
                    imapClient: imapClientStub,
                    pgpMailer: pgpMailerStub
                }, function(err) {
                    expect(err).to.exist;
                    expect(pgpmailerLoginStub.calledOnce).to.be.true;
                    expect(imapLoginStub.calledOnce).to.be.true;
                    expect(dao._account.online).to.be.false;
                    done();
                });
            });

            it('should work when folder already initiated', function(done) {
                dao._account.folders = [];
                imapLoginStub.yields();
                pgpmailerLoginStub.returns();

                dao.onConnect({
                    imapClient: imapClientStub,
                    pgpMailer: pgpMailerStub
                }, function(err) {
                    expect(err).to.not.exist;
                    expect(dao._account.online).to.be.true;
                    expect(dao._imapClient).to.equal(dao._imapClient);
                    expect(dao._smtpClient).to.equal(dao._smtpClient);
                    done();
                });
            });

            it('should work when folder not yet initiated', function(done) {
                var folders = [];
                imapLoginStub.yields();
                pgpmailerLoginStub.returns();
                imapListFoldersStub.yields(null, folders);

                dao.onConnect({
                    imapClient: imapClientStub,
                    pgpMailer: pgpMailerStub
                }, function(err) {
                    expect(err).to.not.exist;
                    expect(dao._account.online).to.be.true;
                    expect(dao._imapClient).to.equal(dao._imapClient);
                    expect(dao._smtpClient).to.equal(dao._smtpClient);
                    expect(dao._account.folders).to.deep.equal(folders);
                    done();
                });
            });
        });

        describe('unlock', function() {
            it('should unlock', function(done) {
                var importMatcher = sinon.match(function(o) {
                    expect(o.passphrase).to.equal(passphrase);
                    expect(o.privateKeyArmored).to.equal(mockKeyPair.privateKey.encryptedKey);
                    expect(o.publicKeyArmored).to.equal(mockKeyPair.publicKey.publicKey);
                    return true;
                });

                pgpStub.importKeys.withArgs(importMatcher).yields();

                dao.unlock({
                    passphrase: passphrase,
                    keypair: mockKeyPair
                }, function(err) {
                    expect(err).to.not.exist;

                    expect(pgpStub.importKeys.calledOnce).to.be.true;

                    done();
                });
            });

            it('should generate a keypair and unlock', function(done) {
                var genKeysMatcher, persistKeysMatcher, importMatcher, keypair;

                keypair = {
                    keyId: 123,
                    publicKeyArmored: mockKeyPair.publicKey.publicKey,
                    privateKeyArmored: mockKeyPair.privateKey.encryptedKey
                };
                genKeysMatcher = sinon.match(function(o) {
                    expect(o.emailAddress).to.equal(emailAddress);
                    expect(o.keySize).to.equal(asymKeySize);
                    expect(o.passphrase).to.equal(passphrase);
                    return true;
                });
                importMatcher = sinon.match(function(o) {
                    expect(o.passphrase).to.equal(passphrase);
                    expect(o.privateKeyArmored).to.equal(mockKeyPair.privateKey.encryptedKey);
                    expect(o.publicKeyArmored).to.equal(mockKeyPair.publicKey.publicKey);
                    return true;
                });
                persistKeysMatcher = sinon.match(function(o) {
                    expect(o).to.deep.equal(mockKeyPair);
                    return true;
                });


                pgpStub.generateKeys.withArgs(genKeysMatcher).yields(null, keypair);
                pgpStub.importKeys.withArgs(importMatcher).yields();
                keychainStub.putUserKeyPair.withArgs().yields();

                dao.unlock({
                    passphrase: passphrase
                }, function(err) {
                    expect(err).to.not.exist;

                    expect(pgpStub.generateKeys.calledOnce).to.be.true;
                    expect(pgpStub.importKeys.calledOnce).to.be.true;
                    expect(keychainStub.putUserKeyPair.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail when persisting fails', function(done) {
                var keypair = {
                    keyId: 123,
                    publicKeyArmored: 'qwerty',
                    privateKeyArmored: 'asdfgh'
                };
                pgpStub.generateKeys.yields(null, keypair);
                pgpStub.importKeys.withArgs().yields();
                keychainStub.putUserKeyPair.yields({});

                dao.unlock({
                    passphrase: passphrase
                }, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.generateKeys.calledOnce).to.be.true;
                    expect(pgpStub.importKeys.calledOnce).to.be.true;
                    expect(keychainStub.putUserKeyPair.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail when import fails', function(done) {
                var keypair = {
                    keyId: 123,
                    publicKeyArmored: 'qwerty',
                    privateKeyArmored: 'asdfgh'
                };

                pgpStub.generateKeys.withArgs().yields(null, keypair);
                pgpStub.importKeys.withArgs().yields({});

                dao.unlock({
                    passphrase: passphrase
                }, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.generateKeys.calledOnce).to.be.true;
                    expect(pgpStub.importKeys.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail when generation fails', function(done) {
                pgpStub.generateKeys.yields({});

                dao.unlock({
                    passphrase: passphrase
                }, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.generateKeys.calledOnce).to.be.true;

                    done();
                });
            });
        });

        describe('_imapParseMessageBlock', function() {
            it('should parse a message', function(done) {
                imapClientStub.parseDecryptedMessageBlock.yields(null, {});

                dao._imapParseMessageBlock(function(err, msg) {
                    expect(err).to.not.exist;
                    expect(msg).to.exist;
                    done();
                });

            });
        });

        describe('_pgpmailerLogin', function() {
            it('should work', function() {
                // called once in onConnect
                expect(pgpMailerStub.login.calledOnce).to.be.true;

                pgpMailerStub.login.returns();

                dao._pgpmailerLogin();

                expect(pgpMailerStub.login.calledTwice).to.be.true;
            });
        });


        describe('_imapLogin', function() {
            it('should fail when disconnected', function(done) {
                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;

                    dao._imapLogin(function(err) {
                        expect(err.code).to.equal(42);
                        done();
                    });
                });
            });

            it('should work', function(done) {
                imapClientStub.login.yields();

                dao._imapLogin(function(err) {
                    expect(err).to.not.exist;
                    done();
                });
            });

            it('should fail due to error in imap login', function(done) {
                imapClientStub.login.yields({});

                dao._imapLogin(function(err) {
                    expect(err).to.exist;
                    done();
                });
            });
        });

        describe('_imapLogout', function() {
            it('should fail when disconnected', function(done) {
                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;

                    dao._imapLogout(function(err) {
                        expect(err.code).to.equal(42);
                        done();
                    });
                });
            });

            it('should work', function(done) {
                imapClientStub.logout.yields();

                dao._imapLogout(function(err) {
                    expect(err).to.not.exist;
                    done();
                });
            });

            it('should fail due to error in imap login', function(done) {
                imapClientStub.logout.yields({});

                dao._imapLogout(function(err) {
                    expect(err).to.exist;
                    done();
                });
            });
        });

        describe('_imapListFolders', function() {
            var dummyFolders = [{
                type: 'Inbox',
                path: 'INBOX'
            }, {
                type: 'Outbox',
                path: 'OUTBOX'
            }];

            it('should list from storage', function(done) {
                devicestorageStub.listItems.withArgs('folders').yields(null, [dummyFolders]);

                dao._imapListFolders(function(err, folders) {
                    expect(err).to.not.exist;
                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(folders[0].type).to.equal('Inbox');
                    done();
                });
            });

            it('should not list from storage due to error', function(done) {
                devicestorageStub.listItems.yields({});

                dao._imapListFolders(function(err, folders) {
                    expect(err).to.exist;
                    expect(folders).to.not.exist;
                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(imapClientStub.listWellKnownFolders.called).to.be.false;
                    done();
                });
            });

            it('should fail when disconnected', function(done) {
                devicestorageStub.listItems.yields(null, []);

                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;

                    dao._imapListFolders(function(err) {
                        expect(err.code).to.equal(42);
                        done();
                    });
                });
            });

            it('should list from imap', function(done) {
                devicestorageStub.listItems.yields(null, []);
                imapClientStub.listWellKnownFolders.yields(null, {
                    inbox: dummyFolders[0]
                });
                devicestorageStub.storeList.yields();

                dao._imapListFolders(function(err, folders) {
                    expect(err).to.not.exist;
                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(imapClientStub.listWellKnownFolders.calledOnce).to.be.true;
                    expect(devicestorageStub.storeList.calledOnce).to.be.true;
                    expect(folders[0].type).to.equal('Inbox');
                    done();
                });
            });

            it('should not list from imap due to store error', function(done) {
                devicestorageStub.listItems.yields(null, []);
                imapClientStub.listWellKnownFolders.yields(null, {
                    inbox: dummyFolders[0]
                });
                devicestorageStub.storeList.yields({});

                dao._imapListFolders(function(err, folders) {
                    expect(err).to.exist;
                    expect(folders).to.not.exist;
                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(imapClientStub.listWellKnownFolders.calledOnce).to.be.true;
                    expect(devicestorageStub.storeList.calledOnce).to.be.true;
                    done();
                });
            });

            it('should not list from imap due to imap error', function(done) {
                devicestorageStub.listItems.yields(null, []);
                imapClientStub.listWellKnownFolders.yields({});

                dao._imapListFolders(function(err, folders) {
                    expect(err).to.exist;
                    expect(folders).to.not.exist;
                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(imapClientStub.listWellKnownFolders.calledOnce).to.be.true;
                    expect(devicestorageStub.storeList.called).to.be.false;
                    done();
                });
            });
        });

        describe('_imapSearch', function() {
            it('should fail when disconnected', function(done) {
                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;

                    dao._imapSearch({}, function(err) {
                        expect(err.code).to.equal(42);
                        done();
                    });
                });
            });

            it('should work', function(done) {
                var path = 'FOLDAAAA';

                imapClientStub.search.withArgs({
                    path: path,
                    subject: '[whiteout] '
                }).yields();

                dao._imapSearch({
                    folder: path
                }, done);
            });
            it('should work', function(done) {
                var path = 'FOLDAAAA';

                imapClientStub.search.withArgs({
                    path: path,
                    subject: '[whiteout] ',
                    answered: true
                }).yields();

                dao._imapSearch({
                    folder: path,
                    answered: true
                }, done);
            });
            it('should work', function(done) {
                var path = 'FOLDAAAA';

                imapClientStub.search.withArgs({
                    path: path,
                    subject: '[whiteout] ',
                    unread: true
                }).yields();

                dao._imapSearch({
                    folder: path,
                    unread: true
                }, done);
            });
        });

        describe('_imapDeleteMessage', function() {
            it('should fail when disconnected', function(done) {
                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;

                    dao._imapDeleteMessage({}, function(err) {
                        expect(err.code).to.equal(42);
                        done();
                    });
                });
            });

            it('should work', function(done) {
                var path = 'FOLDAAAA',
                    uid = 1337;

                imapClientStub.deleteMessage.withArgs({
                    path: path,
                    uid: uid
                }).yields();

                dao._imapDeleteMessage({
                    folder: path,
                    uid: uid
                }, done);
            });
        });

        describe('_imapGetMessage', function() {
            it('should fail when disconnected', function(done) {
                dao.onDisconnect(null, function(err) {
                    expect(err).to.not.exist;

                    dao._imapGetMessage({}, function(err) {
                        expect(err.code).to.equal(42);
                        done();
                    });
                });
            });

            it('should work', function(done) {
                var path = 'FOLDAAAA',
                    uid = 1337;

                imapClientStub.getMessage.withArgs({
                    path: path,
                    uid: uid
                }).yields(null, {});

                dao._imapGetMessage({
                    folder: path,
                    uid: uid
                }, function(err, msg) {
                    expect(err).to.not.exist;
                    expect(msg).to.exist;

                    expect(imapClientStub.getMessage.calledOnce).to.be.true;

                    done();
                });
            });
            it('should not work when getMessage fails', function(done) {
                var path = 'FOLDAAAA',
                    uid = 1337;

                imapClientStub.getMessage.yields({});

                dao._imapGetMessage({
                    folder: path,
                    uid: uid
                }, function(err, msg) {
                    expect(err).to.exist;
                    expect(msg).to.not.exist;

                    expect(imapClientStub.getMessage.calledOnce).to.be.true;

                    done();
                });
            });
        });

        describe('_localListMessages', function() {
            it('should work without uid', function(done) {
                var folder = 'FOLDAAAA';
                devicestorageStub.listItems.withArgs('email_' + folder, 0, null).yields();

                dao._localListMessages({
                    folder: folder
                }, done);
            });

            it('should work with uid', function(done) {
                var folder = 'FOLDAAAA',
                    uid = 123;
                devicestorageStub.listItems.withArgs('email_' + folder + '_' + uid, 0, null).yields();

                dao._localListMessages({
                    folder: folder,
                    uid: uid
                }, done);
            });
        });

        describe('_localStoreMessages', function() {
            it('should work', function(done) {
                var folder = 'FOLDAAAA',
                    emails = [{}];
                devicestorageStub.storeList.withArgs(emails, 'email_' + folder).yields();

                dao._localStoreMessages({
                    folder: folder,
                    emails: emails
                }, done);
            });
        });

        describe('_localDeleteMessage', function() {
            it('should work', function(done) {
                var folder = 'FOLDAAAA',
                    uid = 1337;
                devicestorageStub.removeList.withArgs('email_' + folder + '_' + uid).yields();

                dao._localDeleteMessage({
                    folder: folder,
                    uid: uid
                }, done);
            });

            it('should fail when uid is missing', function(done) {
                var folder = 'FOLDAAAA';

                dao._localDeleteMessage({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;
                    done();
                });
            });
        });

        describe('sync', function() {
            it('should work initially', function(done) {
                var folder, localListStub, invocations, imapSearchStub, imapParseStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder
                }];
                dummyDecryptedMail.unread = true;
                dummyEncryptedMail.unread = true;
                dummyDecryptedMail.attachments = [{
                    filename: 'filename',
                    filesize: 123,
                    mimeType: 'text/plain',
                    content: null
                }, {
                    filename: 'filename',
                    filesize: 123,
                    mimeType: "application/pgp-signature",
                    content: null
                }];

                localListStub = sinon.stub(dao, '_localListMessages').withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail]);
                keychainStub.getReceiverPublicKey.withArgs(dummyEncryptedMail.from[0].address).yields(null, mockKeyPair);
                pgpStub.decrypt.withArgs(dummyEncryptedMail.body, mockKeyPair.publicKey).yields(null, dummyDecryptedMail.body);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);

                imapParseStub = sinon.stub(dao, '_imapParseMessageBlock');
                imapParseStub.withArgs({
                    message: dummyEncryptedMail,
                    block: dummyDecryptedMail.body
                }).yields(null, dummyDecryptedMail);


                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages.length).to.equal(1);
                    expect(dao._account.folders[0].messages[0]).to.equal(dummyDecryptedMail);
                    expect(dao._account.folders[0].messages[0].attachments.length).to.equal(1);
                    expect(localListStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(dao._account.folders[0].count).to.equal(1);
                    expect(imapParseStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should initially error on decryption', function(done) {
                var folder, localListStub, invocations;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [dummyEncryptedMail]);
                keychainStub.getReceiverPublicKey.yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.calledOnce).to.be.true;

                    done();
                });
            });

            it('should initially sync downstream when storage is empty', function(done) {
                var folder, localListStub, localStoreStub, invocations, imapSearchStub, imapGetStub, imapParseStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder
                }];

                dummyDecryptedMail.unread = true;
                dummyDecryptedMail.answered = true;

                localListStub = sinon.stub(dao, '_localListMessages').withArgs({
                    folder: folder
                }).yields(null, []);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').withArgs({
                    folder: folder,
                    uid: dummyEncryptedMail.uid
                }).yields(null, dummyEncryptedMail);
                keychainStub.getReceiverPublicKey.withArgs(dummyEncryptedMail.from[0].address).yields(null, mockKeyPair);
                pgpStub.decrypt.withArgs(dummyEncryptedMail.body, mockKeyPair.publicKey).yields(null, dummyDecryptedMail.body);

                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, [dummyEncryptedMail.uid]);

                imapParseStub = sinon.stub(dao, '_imapParseMessageBlock');
                imapParseStub.yields(null, dummyDecryptedMail);

                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields();

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.calledOnce).to.be.true;
                    expect(dao._account.folders[0].count).to.equal(1);
                    expect(imapParseStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should not work when busy', function(done) {
                dao._account.busy = true;

                dao.sync({
                    folder: 'OOGA'
                }, function(err) {
                    expect(err).to.exist;
                    done();
                });
            });

            it('should fetch messages downstream from the remote', function(done) {
                dao.sync({}, function(err) {
                    expect(err).to.exist;
                    done();
                });
            });

            it('should not work when initial setup errors', function(done) {
                var folder, localListStub;

                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(localListStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should be up to date', function(done) {
                var folder, localListStub, imapSearchStub, invocations;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                localListStub = sinon.stub(dao, '_localListMessages').withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);


                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    done();
                });
            });

            it('should error while searching on imap', function(done) {
                var folder, localListStub, imapSearchStub, invocations;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [dummyEncryptedMail]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields({});

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    done();
                });
            });

            it('should error while listing local messages', function(done) {
                var folder, localListStub;

                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(localListStub.calledOnce).to.be.true;
                    done();
                });
            });

            it('should remove messages from the remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, localDeleteStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [dummyEncryptedMail]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);

                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage').yields();
                localDeleteStub = sinon.stub(dao, '_localDeleteMessage').yields();

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(localDeleteStub.calledOnce).to.be.true;
                    expect(imapDeleteStub.calledOnce).to.be.true;
                    done();
                });
            });

            it('should error while removing messages from local', function(done) {
                var invocations, folder, localListStub, imapSearchStub, localDeleteStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [dummyEncryptedMail]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage').yields();
                localDeleteStub = sinon.stub(dao, '_localDeleteMessage').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(localDeleteStub.calledOnce).to.be.true;
                    expect(imapDeleteStub.calledOnce).to.be.true;
                    expect(imapSearchStub.called).to.be.false;
                    done();
                });
            });

            it('should error while removing messages from the remote', function(done) {
                var folder, localListStub, imapSearchStub, localDeleteStub, imapDeleteStub;

                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [dummyEncryptedMail]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage').yields({});
                localDeleteStub = sinon.stub(dao, '_localDeleteMessage');

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapDeleteStub.calledOnce).to.be.true;
                    expect(localDeleteStub.called).to.be.false;
                    expect(imapSearchStub.called).to.be.false;

                    done();
                });
            });

            it('should delete messages locally if not present on remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, localDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];


                localListStub = sinon.stub(dao, '_localListMessages').withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                localDeleteStub = sinon.stub(dao, '_localDeleteMessage').withArgs({
                    folder: folder,
                    uid: dummyEncryptedMail.uid
                }).yields();

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(localDeleteStub.calledOnce).to.be.true;
                    done();
                });

            });

            it('should error while deleting locally if not present on remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, localDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];


                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [dummyEncryptedMail]);
                localDeleteStub = sinon.stub(dao, '_localDeleteMessage').yields({});
                imapSearchStub = sinon.stub(dao, '_imapSearch').withArgs({
                    folder: folder
                }).yields(null, []);


                dao.sync({
                    folder: folder
                }, function(err) {
                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(localDeleteStub.calledOnce).to.be.true;
                    done();
                });
            });

            it('should fetch legacy messages downstream from the remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').withArgs({
                    folder: folder
                }).yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);

                imapGetStub = sinon.stub(dao, '_imapGetMessage').withArgs({
                    folder: folder,
                    uid: dummyEncryptedMail.uid
                }).yields(null, dummyEncryptedMail);

                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields();
                keychainStub.getReceiverPublicKey.withArgs(dummyEncryptedMail.from[0].address).yields(null, mockKeyPair);
                pgpStub.decrypt.withArgs(dummyEncryptedMail.body, mockKeyPair.publicKey).yields(null, dummyLegacyDecryptedMail.body);


                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.calledOnce).to.be.true;
                    done();
                });
            });

            it('should fetch valid pgp messages downstream from the remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, localStoreStub, imapParseStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];
                dummyDecryptedMail.attachments = [{
                    filename: 'filename',
                    filesize: 123,
                    mimeType: 'text/plain',
                    content: null
                }, {
                    filename: 'filename',
                    filesize: 123,
                    mimeType: "application/pgp-signature",
                    content: null
                }];


                localListStub = sinon.stub(dao, '_localListMessages').withArgs({
                    folder: folder
                }).yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);

                imapGetStub = sinon.stub(dao, '_imapGetMessage').withArgs({
                    folder: folder,
                    uid: dummyEncryptedMail.uid
                }).yields(null, dummyEncryptedMail);

                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields();
                keychainStub.getReceiverPublicKey.withArgs(dummyEncryptedMail.from[0].address).yields(null, mockKeyPair);
                pgpStub.decrypt.withArgs(dummyEncryptedMail.body, mockKeyPair.publicKey).yields(null, dummyDecryptedMail.body);

                imapParseStub = sinon.stub(dao, '_imapParseMessageBlock');
                imapParseStub.withArgs({
                    message: dummyEncryptedMail,
                    block: dummyDecryptedMail.body
                }).yields(null, dummyDecryptedMail);

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages.length).to.equal(1);
                    expect(dao._account.folders[0].messages[0]).to.equal(dummyDecryptedMail);
                    expect(dao._account.folders[0].messages[0].attachments.length).to.equal(1);
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.calledOnce).to.be.true;
                    expect(imapParseStub.calledOnce).to.be.true;
                    done();
                });
            });

            it('should not fetch non-whitelisted mails', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [nonWhitelistedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, nonWhitelistedMail);
                localStoreStub = sinon.stub(dao, '_localStoreMessages');

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.called).to.be.false;
                    expect(keychainStub.getReceiverPublicKey.called).to.be.false;
                    expect(pgpStub.decrypt.called).to.be.false;
                    done();
                });
            });

            it('should error while decrypting fetch messages from the remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, dummyEncryptedMail);
                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields();
                keychainStub.getReceiverPublicKey.yields({});

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.called).to.be.false;
                    done();
                });
            });

            it('should error while storing messages from the remote locally', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, dummyEncryptedMail);
                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(keychainStub.getReceiverPublicKey.called).to.be.false;
                    expect(pgpStub.decrypt.called).to.be.false;
                    done();
                });
            });

            it('should error while fetching messages from the remote', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields({});
                localStoreStub = sinon.stub(dao, '_localStoreMessages');

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(localStoreStub.called).to.be.false;
                    expect(keychainStub.getReceiverPublicKey.called).to.be.false;
                    expect(pgpStub.decrypt.called).to.be.false;
                    done();
                });
            });

            it('should verify an authentication mail', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [verificationMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);

                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, verificationMail);
                keychainStub.verifyPublicKey.withArgs(verificationUuid).yields();
                markReadStub = sinon.stub(dao, '_imapMark').withArgs({
                    folder: folder,
                    uid: verificationMail.uid,
                    unread: false
                }).yields();
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage').withArgs({
                    folder: folder,
                    uid: verificationMail.uid
                }).yields();

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.calledOnce).to.be.true;
                    expect(markReadStub.calledOnce).to.be.true;
                    expect(imapDeleteStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail during deletion of an authentication mail', function(done) {
                var invocations, folder, localListStub, imapSearchStub,
                    imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [verificationMail.uid]);

                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, verificationMail);
                keychainStub.verifyPublicKey.yields();
                markReadStub = sinon.stub(dao, '_imapMark').yields();
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.calledOnce).to.be.true;
                    expect(markReadStub.calledOnce).to.be.true;
                    expect(imapDeleteStub.calledOnce).to.be.true;

                    done();
                });
            });

            it('should fail during marking an authentication mail read', function(done) {
                var invocations, folder, localListStub, imapSearchStub,
                    imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [verificationMail.uid]);

                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, verificationMail);
                keychainStub.verifyPublicKey.yields();
                markReadStub = sinon.stub(dao, '_imapMark').yields({});
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage');

                dao.sync({
                    folder: folder
                }, function(err) {
                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.calledOnce).to.be.true;
                    expect(markReadStub.calledOnce).to.be.true;
                    expect(imapDeleteStub.called).to.be.false;

                    done();
                });
            });

            it('should fail during verifying authentication', function(done) {
                var invocations, folder, localListStub, imapSearchStub,
                    imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [verificationMail.uid]);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, verificationMail);
                keychainStub.verifyPublicKey.yields({});
                markReadStub = sinon.stub(dao, '_imapMark');
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage');

                dao.sync({
                    folder: folder
                }, function(err) {
                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledOnce).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.calledOnce).to.be.true;
                    expect(markReadStub.called).to.be.false;
                    expect(imapDeleteStub.called).to.be.false;

                    done();
                });
            });

            it('should not bother about read authentication mails', function(done) {
                var invocations, folder, localListStub, imapSearchStub,
                    imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                verificationMail.unread = false;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [verificationMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, verificationMail);
                markReadStub = sinon.stub(dao, '_imapMark');
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage');

                dao.sync({
                    folder: folder
                }, function(err) {
                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.not.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.called).to.be.false;
                    expect(markReadStub.called).to.be.false;
                    expect(imapDeleteStub.called).to.be.false;

                    done();
                });
            });

            it('should not bother about corrupted authentication mails', function(done) {
                var invocations, folder, localListStub, imapSearchStub, imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [corruptedVerificationMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);

                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, corruptedVerificationMail);
                markReadStub = sinon.stub(dao, '_imapMark');
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage');

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.called).to.be.false;
                    expect(markReadStub.called).to.be.false;
                    expect(imapDeleteStub.called).to.be.false;

                    done();
                });
            });

            it('should not bother about corrupted authentication mails no verification link', function(done) {
                var invocations, folder, localListStub, imapSearchStub,
                    imapGetStub, markReadStub, imapDeleteStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: []
                }];

                verificationMail.body = 'url? there is no url.';

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, []);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [verificationMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                imapGetStub = sinon.stub(dao, '_imapGetMessage').yields(null, verificationMail);
                markReadStub = sinon.stub(dao, '_imapMark');
                imapDeleteStub = sinon.stub(dao, '_imapDeleteMessage');

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0].messages).to.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(imapGetStub.calledOnce).to.be.true;
                    expect(keychainStub.verifyPublicKey.called).to.be.false;
                    expect(markReadStub.called).to.be.false;
                    expect(imapDeleteStub.called).to.be.false;

                    done();
                });
            });

            it('should sync tags from memory to imap and storage', function(done) {
                var folder, localListStub, imapSearchStub, invocations,
                    markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                var inImap = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inImap.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [inImap.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, [inImap.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                markStub = sinon.stub(dao, '_imapMark').withArgs({
                    folder: folder,
                    uid: dummyDecryptedMail.uid,
                    unread: dummyDecryptedMail.unread,
                    answered: dummyDecryptedMail.answered
                }).yields();
                localStoreStub = sinon.stub(dao, '_localStoreMessages').withArgs({
                    folder: folder,
                    emails: [inStorage]
                }).yields();

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(markStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;

                    expect(inStorage.unread).to.equal(dummyDecryptedMail.unread);
                    expect(inStorage.answered).to.equal(dummyDecryptedMail.answered);

                    done();
                });
            });

            it('should error while syncing unread tags from memory to storage', function(done) {
                var folder, localListStub, imapSearchStub, invocations, markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                var inImap = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inImap.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                markStub = sinon.stub(dao, '_imapMark').yields();
                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(markStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(imapSearchStub.called).to.be.false;
                    done();
                });
            });

            it('should error while syncing answered tags from memory to storage', function(done) {
                var folder, localListStub, imapSearchStub, invocations, markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                var inImap = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inImap.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                markStub = sinon.stub(dao, '_imapMark').yields();
                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(markStub.calledOnce).to.be.true;
                    expect(localStoreStub.calledOnce).to.be.true;
                    expect(imapSearchStub.called).to.be.false;
                    done();
                });
            });

            it('should error while syncing tags from memory to imap', function(done) {
                var folder, localListStub, imapSearchStub, invocations,
                    markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                var inImap = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inImap.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                markStub = sinon.stub(dao, '_imapMark').yields({});
                localStoreStub = sinon.stub(dao, '_localStoreMessages');

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.exist;

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(markStub.calledOnce).to.be.true;
                    expect(localStoreStub.called).to.be.false;
                    expect(imapSearchStub.called).to.be.false;
                    done();
                });
            });

            it('should sync tags from imap to memory and storage', function(done) {
                var folder, localListStub, imapSearchStub, invocations,
                    markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inStorage.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                markStub = sinon.stub(dao, '_imapMark');
                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields();

                dao.sync({
                    folder: folder
                }, function(err) {
                    expect(err).to.not.exist;

                    if (invocations === 0) {
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledTwice).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(markStub.called).to.be.false;
                    expect(localStoreStub.calledOnce).to.be.true;

                    expect(dummyDecryptedMail.unread).to.equal(false);
                    expect(inStorage.unread).to.equal(false);

                    done();
                });
            });

            it('should error while searching for unread tags on imap', function(done) {
                var folder, localListStub, imapSearchStub, invocations, markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inStorage.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields({});
                markStub = sinon.stub(dao, '_imapMark');
                localStoreStub = sinon.stub(dao, '_localStoreMessages');

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(markStub.called).to.be.false;
                    expect(imapSearchStub.calledTwice).to.be.true;
                    expect(localStoreStub.called).to.be.false;

                    expect(inStorage.unread).to.equal(true);
                    expect(dummyDecryptedMail.unread).to.equal(true); // the live object has not been touched!

                    done();
                });
            });

            it('should error while searching for answered tags on imap', function(done) {
                var folder, localListStub, imapSearchStub, invocations, markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inStorage.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields({});
                markStub = sinon.stub(dao, '_imapMark');
                localStoreStub = sinon.stub(dao, '_localStoreMessages');

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledOnce).to.be.true;
                    expect(markStub.called).to.be.false;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(localStoreStub.called).to.be.false;

                    expect(inStorage.unread).to.equal(true);
                    expect(dummyDecryptedMail.unread).to.equal(true); // the live object has not been touched!

                    done();
                });
            });

            it('should error while syncing tags from imap to storage', function(done) {
                var folder, localListStub, imapSearchStub, invocations,
                    markStub, localStoreStub;

                invocations = 0;
                folder = 'FOLDAAAA';
                dao._account.folders = [{
                    type: 'Folder',
                    path: folder,
                    messages: [dummyDecryptedMail]
                }];

                var inStorage = JSON.parse(JSON.stringify(dummyEncryptedMail));
                dummyDecryptedMail.unread = inStorage.unread = true;

                localListStub = sinon.stub(dao, '_localListMessages').yields(null, [inStorage]);
                imapSearchStub = sinon.stub(dao, '_imapSearch');
                imapSearchStub.withArgs({
                    folder: folder
                }).yields(null, [dummyEncryptedMail.uid]);
                imapSearchStub.withArgs({
                    folder: folder,
                    unread: true
                }).yields(null, []);
                imapSearchStub.withArgs({
                    folder: folder,
                    answered: true
                }).yields(null, []);
                markStub = sinon.stub(dao, '_imapMark');
                localStoreStub = sinon.stub(dao, '_localStoreMessages').yields({});

                dao.sync({
                    folder: folder
                }, function(err) {

                    if (invocations === 0) {
                        expect(err).to.not.exist;
                        expect(dao._account.busy).to.be.true;
                        invocations++;
                        return;
                    }

                    expect(err).to.exist;
                    expect(dao._account.busy).to.be.false;
                    expect(dao._account.folders[0]).to.not.be.empty;
                    expect(localListStub.calledTwice).to.be.true;
                    expect(imapSearchStub.calledThrice).to.be.true;
                    expect(markStub.called).to.be.false;
                    expect(localStoreStub.calledOnce).to.be.true;

                    done();
                });
            });
        });

        describe('mark', function() {
            it('should work', function(done) {
                imapClientStub.updateFlags.withArgs({
                    path: 'asdf',
                    uid: 1,
                    unread: false,
                    answered: false
                }).yields();

                dao._imapMark({
                    folder: 'asdf',
                    uid: 1,
                    unread: false,
                    answered: false
                }, function(err) {
                    expect(imapClientStub.updateFlags.calledOnce).to.be.true;
                    expect(err).to.not.exist;
                    done();
                });
            });
        });

        describe('move', function() {
            it('should work', function(done) {
                imapClientStub.moveMessage.withArgs({
                    path: 'asdf',
                    uid: 1,
                    destination: 'asdasd'
                }).yields();

                dao.move({
                    folder: 'asdf',
                    uid: 1,
                    destination: 'asdasd'
                }, function(err) {
                    expect(imapClientStub.moveMessage.calledOnce).to.be.true;
                    expect(err).to.not.exist;
                    done();
                });
            });
        });

        describe('sendPlaintext', function() {
            it('should work', function(done) {
                pgpMailerStub.send.withArgs({
                    mail: dummyEncryptedMail
                }).yields();

                dao.sendPlaintext({
                    email: dummyEncryptedMail
                }, function(err) {
                    expect(err).to.not.exist;
                    expect(pgpMailerStub.send.calledOnce).to.be.true;
                    done();
                });
            });

            it('should not work when pgpmailer fails', function(done) {
                pgpMailerStub.send.yields({});

                dao.sendPlaintext({
                    email: dummyEncryptedMail
                }, function(err) {
                    expect(err).to.exist;
                    expect(pgpMailerStub.send.calledOnce).to.be.true;
                    done();
                });
            });
        });

        describe('sendEncrypted', function() {
            it('should work', function(done) {
                pgpStub.exportKeys.yields(null, {
                    privateKeyArmored: mockKeyPair.privateKey.encryptedKey,
                    publicKeyArmored: mockKeyPair.publicKey.publicKey
                });

                pgpMailerStub.send.withArgs({
                    encrypt: true,
                    cleartextMessage: str.message,
                    mail: dummyDecryptedMail,
                    publicKeysArmored: dummyDecryptedMail.receiverKeys
                }).yields();

                dao.sendEncrypted({
                    email: dummyDecryptedMail
                }, function(err) {
                    expect(err).to.not.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpMailerStub.send.calledOnce).to.be.true;

                    done();
                });
            });
            it('should not work when pgpmailer fails', function(done) {
                pgpStub.exportKeys.yields(null, {
                    privateKeyArmored: mockKeyPair.privateKey.encryptedKey,
                    publicKeyArmored: mockKeyPair.publicKey.publicKey
                });
                pgpMailerStub.send.yields({});

                dao.sendEncrypted({
                    email: dummyDecryptedMail
                }, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpMailerStub.send.calledOnce).to.be.true;

                    done();
                });
            });
            it('should not work when sender key export fails', function(done) {
                pgpStub.exportKeys.yields({});

                dao.sendEncrypted({
                    email: dummyDecryptedMail
                }, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpMailerStub.send.calledOnce).to.be.false;

                    done();
                });
            });
        });

        describe('storeForOutbox', function() {
            it('should work', function(done) {
                var key = 'omgsocrypto';

                pgpStub.exportKeys.yields(null, {
                    publicKeyArmored: key
                });
                pgpStub.encrypt.withArgs(dummyDecryptedMail.body, [key]).yields(null, 'asdfasfd');
                devicestorageStub.storeList.withArgs([dummyDecryptedMail], 'email_OUTBOX').yields();

                dao.storeForOutbox(dummyDecryptedMail, function(err) {
                    expect(err).to.not.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.encrypt.calledOnce).to.be.true;
                    expect(devicestorageStub.storeList.calledOnce).to.be.true;

                    done();
                });
            });

            it('should work when store fails', function(done) {
                var key = 'omgsocrypto';

                pgpStub.exportKeys.yields(null, {
                    publicKeyArmored: key
                });
                pgpStub.encrypt.yields(null, 'asdfasfd');
                devicestorageStub.storeList.yields({});

                dao.storeForOutbox(dummyDecryptedMail, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.encrypt.calledOnce).to.be.true;
                    expect(devicestorageStub.storeList.calledOnce).to.be.true;

                    done();
                });
            });

            it('should work when encryption fails', function(done) {
                var key = 'omgsocrypto';

                pgpStub.exportKeys.yields(null, {
                    publicKeyArmored: key
                });
                pgpStub.encrypt.yields({});

                dao.storeForOutbox(dummyDecryptedMail, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.encrypt.calledOnce).to.be.true;
                    expect(devicestorageStub.storeList.called).to.be.false;

                    done();
                });
            });

            it('should work when key export fails', function(done) {
                pgpStub.exportKeys.yields({});

                dao.storeForOutbox(dummyDecryptedMail, function(err) {
                    expect(err).to.exist;

                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.encrypt.called).to.be.false;
                    expect(devicestorageStub.storeList.called).to.be.false;

                    done();
                });
            });
        });

        describe('listForOutbox', function() {
            it('should work', function(done) {
                var key = 'omgsocrypto';

                devicestorageStub.listItems.withArgs('email_OUTBOX', 0, null).yields(null, [dummyEncryptedMail]);
                pgpStub.exportKeys.yields(null, {
                    publicKeyArmored: key
                });
                pgpStub.decrypt.withArgs(dummyEncryptedMail.body, key).yields(null, dummyDecryptedMail.body);

                dao.listForOutbox(function(err, mails) {
                    expect(err).to.not.exist;

                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.calledOnce).to.be.true;
                    expect(mails.length).to.equal(1);
                    expect(mails[0].body).to.equal(dummyDecryptedMail.body);

                    done();
                });
            });

            it('should not work when decryption fails', function(done) {
                var key = 'omgsocrypto',
                    errMsg = 'THIS IS AN ERROR!';

                devicestorageStub.listItems.yields(null, [dummyEncryptedMail]);
                pgpStub.exportKeys.yields(null, {
                    publicKeyArmored: key
                });
                pgpStub.decrypt.yields({
                    errMsg: errMsg
                });

                dao.listForOutbox(function(err, mails) {
                    expect(err).to.not.exist;
                    expect(mails[0].body).to.equal(errMsg);

                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.calledOnce).to.be.true;

                    done();
                });
            });

            it('should not work when key export fails', function(done) {
                devicestorageStub.listItems.yields(null, [dummyEncryptedMail]);
                pgpStub.exportKeys.yields({});

                dao.listForOutbox(function(err, mails) {
                    expect(err).to.exist;
                    expect(mails).to.not.exist;

                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(pgpStub.exportKeys.calledOnce).to.be.true;
                    expect(pgpStub.decrypt.called).to.be.false;

                    done();
                });
            });

            it('should not work when list from storage fails', function(done) {
                devicestorageStub.listItems.yields({});

                dao.listForOutbox(function(err, mails) {
                    expect(err).to.exist;
                    expect(mails).to.not.exist;

                    expect(devicestorageStub.listItems.calledOnce).to.be.true;
                    expect(pgpStub.exportKeys.called).to.be.false;
                    expect(pgpStub.decrypt.called).to.be.false;

                    done();
                });
            });
        });
    });
});