'use strict';

/**
 * Services that persists and retrieves user from localStorage.
 */

angular.module('userServices', []).
  factory('User', ['$rootScope', '$http', '$location', '$window', 'API_URL', 'STORAGE_USER_ID', 'STORAGE_SETTINGS_ID',
    function($rootScope, $http, $location, $window, API_URL, STORAGE_USER_ID, STORAGE_SETTINGS_ID) {
      var authenticated = false,
        defaultSettings = {
          auth: { apiId: '', apiToken: ''},
          sync: {
            queue: [], //here OT will be queued up, this is NOT call-back queue!
            sent: [] //here will be OT which have been sent, but we have not got reply from server yet.
          },
          fetching: false,  // whether fetch() was called or no. this is to avoid race conditions
          online: false
        },
        settings = {}, //habit mobile settings (like auth etc.) to be stored here
        user = {}; // this is stored as a reference accessible to all controllers, that way updates propagate

      //first we populate user with schema
      user.apiToken = user._id = ''; // we use id / apitoken to determine if registered

      //than we try to load localStorage
      if (localStorage.getItem(STORAGE_USER_ID)) {
          _.extend(user, JSON.parse(localStorage.getItem(STORAGE_USER_ID)));
      }
      user._wrapped = false;

      var syncQueue = function (cb) {
        if (!authenticated) {
          $window.alert("Not authenticated, can't sync, go to settings first.");
          return;
        }

        var queue = settings.sync.queue;
        var sent = settings.sync.sent;
        if (queue.length === 0) {
          // Sync: Queue is empty
          return;
        }
        if (settings.fetching) {
          // Sync: Already fetching
          return;
        }
        if (settings.online!==true) {
          // Sync: Not online
          return;
        }

        settings.fetching = true;
        // move all actions from queue array to sent array
        _.times(queue.length, function () {
          sent.push(queue.shift());
        });

        $http.post(API_URL + '/api/v1/user/batch-update', sent, {params: {data:+new Date, _v:user._v, siteVersion: $window.env && $window.env.siteVersion}})
          .success(function (data, status, heacreatingders, config) {
            //make sure there are no pending actions to sync. If there are any it is not safe to apply model from server as we may overwrite user data.
            if (!queue.length) {
              //we can't do user=data as it will not update user references in all other angular controllers.

              // the user has been modified from another application, sync up
              if(data.wasModified) {
                delete data.wasModified;
                $rootScope.$emit('userUpdated', user);
              }

              // Update user
              _.extend(user, data);
              if (!user._wrapped){
                $rootScope.Shared.wrap(user);
                _.each(user.ops, function(op,k){
                  user.ops[k] = _.partialRight(op, function(err, req){
                    //if (err) return Notification.text(err); // FIXME Circular dependency found: Notification <- User
                    if (err) return alert(err);
                    userServices.log({op:k, params: req.params, query:req.query, body:req.body});
                  });
                });
              }

              // Emit event when user is synced
              $rootScope.$emit('userSynced');
            }
            sent.length = 0;
            settings.fetching = false;
            save();
            if (cb) {
              cb(false)
            }

            syncQueue(); // call syncQueue to check if anyone pushed more actions to the queue while we were talking to server.
          })
          .error(function (data, status, headers, config) {
            if(status === 400 && data.needRefresh === true){
              alert("The site has been updated and the page needs to refresh. " +
                "The last action has not been recorded, please do it again once the page reloads."
                );

              return location.reload();
            }
            //move sent actions back to queue
            _.times(sent.length, function () {
                queue.push(sent.shift())
            });
            settings.fetching = false;
            //Notification.push({type:'text', text:"We're offline"})
          });
      }


      var save = function () {
        localStorage.setItem(STORAGE_USER_ID, JSON.stringify(user));
        localStorage.setItem(STORAGE_SETTINGS_ID, JSON.stringify(settings));
      };
      var userServices = {
        user: user,
        set: function(updates) {
          user.ops.update({body:updates});
        },
        online: function (status) {
          if (status===true) {
            settings.online = true;
            syncQueue();
          } else {
            settings.online = false;
          };
        },

        authenticate: function (uuid, token, cb) {
          if (!!uuid && !!token) {
            $http.defaults.headers.common['x-api-user'] = uuid;
            $http.defaults.headers.common['x-api-key'] = token;
            authenticated = true;
            settings.auth.apiId = uuid;
            settings.auth.apiToken = token;
            settings.online = true;
            if (user && user._v) user._v--; // shortcut to always fetch new updates on page reload
            userServices.log({}, function(){
              // If they don't have timezone, set it
              var offset = moment().zone(); // eg, 240 - this will be converted on server as -(offset/60)
              if (user.preferences.timezoneOffset !== offset)
                userServices.set({'preferences.timezoneOffset': offset});
              cb && cb();
            });
          } else {
            alert('Please enter your ID and Token in settings.')
          }
        },

        authenticated: function(){
          return this.settings.auth.apiId !== "";
        },

        log: function (action, cb) {
          //push by one buy one if an array passed in.
          if (_.isArray(action)) {
            action.forEach(function (a) {
              settings.sync.queue.push(a);
            });
          } else {
            settings.sync.queue.push(action);
          }

          save();
          syncQueue(cb);
        },

        sync: function(){
          user._v--;
          userServices.log({});
        },

        save: save,

        settings: settings
      };


      //load settings if we have them
      if (localStorage.getItem(STORAGE_SETTINGS_ID)) {
        //use extend here to make sure we keep object reference in other angular controllers
        _.extend(settings, JSON.parse(localStorage.getItem(STORAGE_SETTINGS_ID)));

        //if settings were saved while fetch was in process reset the flag.
        settings.fetching = false;
      //create and load if not
      } else {
        localStorage.setItem(STORAGE_SETTINGS_ID, JSON.stringify(defaultSettings));
        _.extend(settings, defaultSettings);
      }

      //If user does not have ApiID that forward him to settings.
      if (!settings.auth.apiId || !settings.auth.apiToken) {
        //var search = $location.search(); // FIXME this should be working, but it's returning an empty object when at a root url /?_id=...
        var search = $location.search($window.location.search.substring(1)).$$search; // so we use this fugly hack instead
        if (search.err) return alert(search.err);
        if (search._id && search.apiToken) {
          userServices.authenticate(search._id, search.apiToken, function(){
            $window.location.href='/';
          });
        } else {
          if ($window.location.pathname.indexOf('/static') !== 0){
            localStorage.clear();
            $window.location.href = '/logout';
          }
        }
      } else {
        userServices.authenticate(settings.auth.apiId, settings.auth.apiToken)
      }

      return userServices;
    }
]);