define([
    'jquery',
    '/bower_components/chainpad-listmap/chainpad-listmap.js',
    '/bower_components/chainpad-crypto/crypto.js?v=0.1.5',
    '/bower_components/textpatcher/TextPatcher.amd.js',
    '/common/userObject.js',
    '/common/migrate-user-object.js'
], function ($, Listmap, Crypto, TextPatcher, FO, Migrate) {
    /*
        This module uses localStorage, which is synchronous, but exposes an
        asyncronous API. This is so that we can substitute other storage
        methods.

        To override these methods, create another file at:
        /customize/storage.js
    */

    var Store = {};
    var store;

    var initStore = function (filesOp, storeObj, exp) {
        var ret = {};

        var safeSet = function (key, val) {
            storeObj[key] = val;
        };

        // Store uses nodebacks...
        ret.set = function (key, val, cb) {
            safeSet(key, val);
            cb();
        };

        // implement in alternative store
        ret.setBatch = function (map, cb) {
            Object.keys(map).forEach(function (key) {
                safeSet(key, map[key]);
            });
            cb(void 0, map);
        };

        ret.setDrive = function (key, val, cb) {
            storeObj.drive[key] = val;
            cb();
        };

        var safeGet = function (key) {
            return storeObj[key];
        };

        ret.get = function (key, cb) {
            cb(void 0, safeGet(key));
        };

        // implement in alternative store
        ret.getBatch = function (keys, cb) {
            var res = {};
            keys.forEach(function (key) {
                res[key] = safeGet(key);
            });
            cb(void 0, res);
        };

        var getAttributeObject = function (attr) {
            if (typeof attr === "string") {
                console.error('DEPRECATED: use setAttribute with an array, not a string');
                return {
                    obj: storeObj.settings,
                    key: attr
                };
            }
            if (!Array.isArray(attr)) { throw new Error("Attribute must be string or array"); }
            if (attr.length === 0) { throw new Error("Attribute can't be empty"); }
            var obj = storeObj.settings;
            attr.forEach(function (el, i) {
                if (i === attr.length-1) { return; }
                if (!obj[el]) {
                    obj[el] = {};
                }
                else if (typeof obj[el] !== "object") { throw new Error("Wrong attribute"); }
                obj = obj[el];
            });
            return {
                obj: obj,
                key: attr[attr.length-1]
            };
        };
        ret.setAttribute = function (attr, value, cb) {
            try {
                var object = getAttributeObject(attr);
                object.obj[object.key] = value;
            } catch (e) { return void cb(e); }
            cb();
        };
        ret.getAttribute = function (attr, cb) {
            var object;
            try {
                object = getAttributeObject(attr);
            } catch (e) { return void cb(e); }
            cb(null, object.obj[object.key]);
        };
        ret.setPadAttribute = filesOp.setPadAttribute;
        ret.getPadAttribute = filesOp.getPadAttribute;
        ret.getIdFromHref = filesOp.getIdFromHref;

        ret.getDrive = function (key, cb) {
            cb(void 0, storeObj.drive[key]);
        };

        var safeRemove = function (key) {
            delete storeObj[key];
        };

        ret.remove = function (key, cb) {
            safeRemove(key);
            cb();
        };

        // implement in alternative store
        ret.removeBatch = function (keys, cb) {
            keys.forEach(function (key) {
                safeRemove(key);
            });
            cb();
        };

        ret.keys = function (cb) {
            cb(void 0, Object.keys(storeObj));
        };

        ret.removeData = filesOp.removeData;
        ret.pushData = filesOp.pushData;
        ret.addPad = filesOp.add;

        ret.forgetPad = function (href, cb) {
            filesOp.forget(href);
            cb();
        };

        ret.listTemplates = function () {
            var templateFiles = filesOp.getFiles(['template']);
            var res = [];
            templateFiles.forEach(function (f) {
                var data = filesOp.getFileData(f);
                res.push(JSON.parse(JSON.stringify(data)));
            });
            return res;
        };

        ret.getProxy = function () {
            return exp;
        };

        ret.getLoginName = function () {
            return storeObj.login_name;
        };

        ret.repairDrive = function () {
            filesOp.fixFiles();
        };

        ret.getEmptyObject = function () {
            return filesOp.getStructure();
        };

        ret.replace = filesOp.replace;

        ret.restoreHref = filesOp.restoreHref;

        ret.changeHandlers = [];

        ret.change = function () {};

        ret.getProfile = function () {
            return storeObj.profile;
        };

        return ret;
    };

    var tryParsing = function (x) {
        try { return JSON.parse(x); }
        catch (e) {
            console.error(e);
            return null;
        }
    };

    var onReady = function (f, proxy, Cryptpad, exp) {
        var fo = exp.fo = FO.init(proxy.drive, {
            Cryptpad: Cryptpad,
            rt: exp.realtime
        });
        var todo = function () {
            fo.fixFiles();

            Migrate(proxy, Cryptpad);

            //storeObj = proxy;
            store = initStore(fo, proxy, exp);
            if (typeof(f) === 'function') {
                f(void 0, store);
            }

            var requestLogin = function () {
                // log out so that you don't go into an endless loop...
                Cryptpad.logout();

                // redirect them to log in, and come back when they're done.
                sessionStorage.redirectTo = window.location.href;
                window.location.href = '/login/';
            };

            var tokenKey = 'loginToken';
            if (Cryptpad.isLoggedIn()) {
    /*  This isn't truly secure, since anyone who can read the user's object can
        set their local loginToken to match that in the object. However, it exposes
        a UI that will work most of the time. */

                // every user object should have a persistent, random number
                if (typeof(proxy.loginToken) !== 'number') {
                    proxy[tokenKey] = Math.floor(Math.random()*Number.MAX_SAFE_INTEGER);
                }

                // copy User_hash into sessionStorage because cross-domain iframes
                // on safari replaces localStorage with sessionStorage or something
                if (sessionStorage) { sessionStorage.setItem('User_hash', localStorage.getItem('User_hash')); }

                var localToken = tryParsing(localStorage.getItem(tokenKey));
                if (localToken === null) {
                    // if that number hasn't been set to localStorage, do so.
                    localStorage.setItem(tokenKey, proxy.loginToken);
                } else if (localToken !== proxy[tokenKey]) {
                    // if it has been, and the local number doesn't match that in
                    // the user object, request that they reauthenticate.
                    return void requestLogin();
                }
            }

            if (typeof(proxy.allowUserFeedback) !== 'boolean') {
                proxy.allowUserFeedback = true;
            }

            if (typeof(proxy.uid) !== 'string' || proxy.uid.length !== 32) {
                // even anonymous users should have a persistent, unique-ish id
                console.log('generating a persistent identifier');
                proxy.uid = Cryptpad.createChannelId();
            }

            // if the user is logged in, but does not have signing keys...
            if (Cryptpad.isLoggedIn() && (!Cryptpad.hasSigningKeys(proxy) ||
                !Cryptpad.hasCurveKeys(proxy))) {
                return void requestLogin();
            }

            proxy.on('change', [Cryptpad.displayNameKey], function (o, n) {
                if (typeof(n) !== "string") { return; }
                Cryptpad.changeDisplayName(n);
            });
            proxy.on('change', ['profile'], function () {
                // Trigger userlist update when the avatar has changed
                Cryptpad.changeDisplayName(proxy[Cryptpad.displayNameKey]);
            });
            proxy.on('change', ['friends'], function () {
                // Trigger userlist update when the avatar has changed
                Cryptpad.changeDisplayName(proxy[Cryptpad.displayNameKey]);
            });
            proxy.on('change', [tokenKey], function () {
                var localToken = tryParsing(localStorage.getItem(tokenKey));
                if (localToken !== proxy[tokenKey]) {
                    return void requestLogin();
                }
            });
        };
        fo.migrate(todo);
    };

    var initialized = false;

    var init = function (f, Cryptpad) {
        if (!Cryptpad || initialized) { return; }
        initialized = true;

        var hash = Cryptpad.getUserHash() || localStorage.FS_hash || Cryptpad.createRandomHash();
        if (!hash) {
            throw new Error('[Store.init] Unable to find or create a drive hash. Aborting...');
        }
        var secret = Cryptpad.getSecrets('drive', hash);
        var listmapConfig = {
            data: {},
            websocketURL: Cryptpad.getWebsocketURL(),
            channel: secret.channel,
            readOnly: false,
            validateKey: secret.keys.validateKey || undefined,
            crypto: Crypto.createEncryptor(secret.keys),
            userName: 'fs',
            logLevel: 1,
        };

        var exp = {};

        window.addEventListener('storage', function (e) {
            if (e.key !== Cryptpad.userHashKey) { return; }
            var o = e.oldValue;
            var n = e.newValue;
            if (!o && n) {
                window.location.reload();
            } else if (o && !n) {
                $(window).on('keyup', function (e) {
                    if (e.keyCode === 27) {
                        Cryptpad.removeLoadingScreen();
                    }
                });
                Cryptpad.logout();
                Cryptpad.addLoadingScreen({hideTips: true});
                Cryptpad.errorLoadingScreen(Cryptpad.Messages.onLogout, true);
                if (exp.info) {
                    exp.info.network.disconnect();
                }
            }
        });

        var rt = window.rt = Listmap.create(listmapConfig);

        exp.realtime = rt.realtime;
        exp.proxy = rt.proxy;
        rt.proxy.on('create', function (info) {
            exp.info = info;
            if (!Cryptpad.getUserHash()) {
                localStorage.FS_hash = Cryptpad.getEditHashFromKeys(info.channel, secret.keys);
            }
        }).on('ready', function () {
            if (store) { return; } // the store is already ready, it is a reconnection
            if (!rt.proxy.drive || typeof(rt.proxy.drive) !== 'object') { rt.proxy.drive = {}; }
            var drive = rt.proxy.drive;
            // Creating a new anon drive: import anon pads from localStorage
            if ((!drive[Cryptpad.oldStorageKey] || !Cryptpad.isArray(drive[Cryptpad.oldStorageKey]))
                && !drive['filesData']) {
                drive[Cryptpad.oldStorageKey] = [];
                onReady(f, rt.proxy, Cryptpad, exp);
                return;
            }
            // Drive already exist: return the existing drive, don't load data from legacy store
            onReady(f, rt.proxy, Cryptpad, exp);
        })
        .on('disconnect', function (info) {
            // We only manage errors during the loading screen here. Other websocket errors are handled by the apps
            if (info.error) {
                if (typeof Cryptpad.storeError === "function") {
                    Cryptpad.storeError();
                }
                return;
            }
        })
        .on('change', ['drive', 'migrate'], function () {
            var path = arguments[2];
            var value = arguments[1];
            if (path[0] === 'drive' && path[1] === "migrate" && value === 1) {
                rt.network.disconnect();
                rt.realtime.abort();
                Cryptpad.alert(Cryptpad.Messages.fs_migration, null, true);
            }
        });
    };

    Store.ready = function (f, Cryptpad) {
        if (store) { // Store.ready probably called twice, store already ready
            if (typeof(f) === 'function') {
                f(void 0, store);
            }
        } else {
            init(f, Cryptpad);
        }
    };

    return Store;
});