(function (){
    "use strict";

    angular.module('shared')
        .factory('folderListItemAmbassador', ['$rootScope', '_', dataService]);

    function dataService($rootScope, _) {
        var activeFolderListItem = {id: 0, isChecked: false};
        var selectedFolderListItem = {id: 0, isChecked: false};

        var previousShownFolders = {};

        var ACTIVE_FOLDER_LIST_ITEM_CHANGED = "folderListItemActiveChanged";
        var SELECTED_FOLDER_LIST_ITEM_CHANGED = "folderListItemSelectedChanged";

        return {
            registerOnActiveFolderListItemChanged: registerOnActiveFolderListItemChanged,
            registerOnSelectedFolderListItemChanged: registerOnSelectedFolderListItemChanged,
            setActiveFolderListItem: setActiveFolderListItem,
            setSelectedFolderListItem: setSelectedFolderListItem,
            getActiveFolderListItem: getActiveFolderListItem,
            getSelectedFolderListItem: getSelectedFolderListItem,
            resetActiveFolderListItem: resetActiveFolderListItem,
            resetSelectedFolderListItem: resetSelectedFolderListItem,
            getPreviousShownFolders: getPreviousShownFolders,
            findPreviousShownFolders: findPreviousShownFolders,
            savePreviousShownFolders: savePreviousShownFolders,
            reinstateShownFolders: reinstateShownFolders,
            expandLastSavedFolderForShownFolders: expandLastSavedFolderForShownFolders
        };

        function registerOnActiveFolderListItemChanged(scope, callback) {
            var eventListenDestructor = $rootScope.$on(ACTIVE_FOLDER_LIST_ITEM_CHANGED, callback);
            scope.$on('$destroy', eventListenDestructor);
        }

        function registerOnSelectedFolderListItemChanged(scope, callback) {
            var eventListenDestructor = $rootScope.$on(SELECTED_FOLDER_LIST_ITEM_CHANGED, callback);
            scope.$on('$destroy', eventListenDestructor);
        }

        function setActiveFolderListItem(folderListItem) {
            resetSelectedFolderListItem();
            if (activeFolderListItem.id === folderListItem.id) {
                return;
            }
            activeFolderListItem = folderListItem;
            emitActiveFolderListItemChanged();
        }

        function setSelectedFolderListItem(folderListItem) {
            resetActiveFolderListItem();
            if (selectedFolderListItem.id === folderListItem.id) {
                return;
            }
            selectedFolderListItem = folderListItem;
            emitSelectedFolderListItemChanged();
        }

        function getActiveFolderListItem() {
            return activeFolderListItem;
        }

        function getSelectedFolderListItem() {
            return selectedFolderListItem;
        }

        function resetActiveFolderListItem() {
            if (activeFolderListItem.id === 0) {
                return;
            }
            activeFolderListItem = {id: 0, isChecked: false};
            emitActiveFolderListItemChanged();
        }

        function resetSelectedFolderListItem() {
            if (selectedFolderListItem.id === 0) {
                return;
            }
            selectedFolderListItem = {id: 0, isChecked: false};
            emitSelectedFolderListItemChanged();
        }

        function emitActiveFolderListItemChanged() {
            $rootScope.$emit(ACTIVE_FOLDER_LIST_ITEM_CHANGED);
        }

        function emitSelectedFolderListItemChanged() {
            $rootScope.$emit(SELECTED_FOLDER_LIST_ITEM_CHANGED);
        }

        function getPreviousShownFolders() {
            return previousShownFolders;
        }

        function findPreviousShownFolders(folderId) {
            var showFolders = true;

            if (folderId && previousShownFolders && previousShownFolders[folderId]) {
                showFolders = previousShownFolders[folderId].showFolders;
            }

            return showFolders;
        }

        function savePreviousShownFolders(folderList) {
            folderList.forEach(function (folder) {
                previousShownFolders[folder.id] = [];
                previousShownFolders[folder.id].showFolders = folder.showFolders;
                if (folder.children) {
                    savePreviousShownFolders(folder.children);
                }
            });
        }

        function reinstateShownFolders(folderList, newFolderId) {
            folderList.forEach(function (folder, index) {
                if (folder.id && previousShownFolders && previousShownFolders[folder.id]) {
                    this[index].showFolders = previousShownFolders[folder.id].showFolders;
                }

                if (parseInt(this[index].id, 10) === parseInt(newFolderId, 10)) {
                    previousShownFolders[this[index].id].showFolders = true;
                    this[index].showFolders = true;
                }

                if (folder.children) {
                    reinstateShownFolders(folder.children);
                }
            }, folderList);

            return folderList;
        }

        function expandLastSavedFolderForShownFolders(folderList, folderIdsToSave) {
            folderList.forEach(function (folder, index) {
                previousShownFolders[folder.id] = [];

                if (folder.id && folderIdsToSave.indexOf(folder.id) !== -1) {
                    this[index].showFolders = true;
                    previousShownFolders[folder.id].showFolders = true;
                } else {
                    this[index].showFolders = false;
                    previousShownFolders[folder.id].showFolders = false;
                }

                if (folder.children) {
                    expandLastSavedFolderForShownFolders(folder.children, folderIdsToSave);
                }
            }, folderList);
        }
    }
})();