/************************************************************************
 * This file is part of EspoCRM.
 *
 * EspoCRM - Open Source CRM application.
 * Copyright (C) 2014-2022 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
 * Website: https://www.espocrm.com
 *
 * EspoCRM is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * EspoCRM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU General Public License version 3.
 *
 * In accordance with Section 7(b) of the GNU General Public License version 3,
 * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
 ************************************************************************/

define('language', ['ajax'], function (Ajax) {

    /**
     * A language.
     *
     * @class
     * @name Class
     * @memberOf module:language
     * @param {module:cache.Class} [cache] A cache.
     */
    let Language = function (cache) {
        /**
         * @private
         * @type {module:cache.Class|null}
         */
        this.cache = cache || null;

        /**
         * @private
         * @type {Object}
         */
        this.data = {};

        /**
         * A name.
         *
         * @type {string}
         */
        this.name = 'default';
    };

    _.extend(Language.prototype, /** @lends module:language.Class# */{

        /**
         * @private
         */
        url: 'I18n',

        /**
         * Whether an item is set in language data.
         *
         * @param {string} scope A scope.
         * @param {string} category A category.
         * @param {string} name An item name.
         * @returns {boolean}
         */
        has: function (name, category, scope) {
            if (scope in this.data) {
                if (category in this.data[scope]) {
                    if (name in this.data[scope][category]) {
                        return true;
                    }
                }
            }

            return false;
        },

        /**
         * Get a value set in language data.
         *
         * @param {string} scope A scope.
         * @param {string} category A category.
         * @param {string} name An item name.
         * @returns {*}
         */
        get: function (scope, category, name) {
            if (scope in this.data) {
                if (category in this.data[scope]) {
                    if (name in this.data[scope][category]) {
                        return this.data[scope][category][name];
                    }
                }
            }

            if (scope === 'Global') {
                return name;
            }

            return false;
        },

        /**
         * Translate a label.
         *
         * @param {string} name An item name.
         * @param {string|null} [category='labels'] A category.
         * @param {string|null} [scope='Global'] A scope.
         * @returns {string}
         */
        translate: function (name, category, scope) {
            scope = scope || 'Global';
            category = category || 'labels';

            let res = this.get(scope, category, name);

            if (res === false && scope !== 'Global') {
                res = this.get('Global', category, name);
            }

            return res;
        },

        /**
         * Translation an option item value.
         *
         * @param {string} value An option value.
         * @param {string} field A field name.
         * @param {string} [scope='Global'] A scope.
         * @returns {string}
         */
        translateOption: function (value, field, scope) {
            let translation = this.translate(field, 'options', scope);

            if (typeof translation !== 'object') {
                translation = {};
            }

            return translation[value] || value;
        },

        /**
         * @private
         */
        loadFromCache: function (loadDefault) {
            let name = this.name;
            if (loadDefault) {
                name = 'default';
            }

            if (this.cache) {
                let cached = this.cache.get('app', 'language-' + name);

                if (cached) {
                    this.data = cached;

                    return true;
                }
            }

            return null;
        },

        /**
         * Clear a language cache.
         */
        clearCache: function () {
            if (this.cache) {
                this.cache.clear('app', 'language-' + this.name);
            }
        },

        /**
         * @private
         */
        storeToCache: function (loadDefault) {
            let name = this.name;

            if (loadDefault) {
                name = 'default';
            }

            if (this.cache) {
                this.cache.set('app', 'language-' + name, this.data);
            }
        },

        /**
         * Load data from cache or backend (if not yet cached).
         *
         * @param {Function} [callback] Deprecated.
         * @param {boolean} [disableCache=false] Deprecated
         * @param {boolean} [loadDefault=false] Deprecated.
         * @returns {Promise}
         */
        load: function (callback, disableCache, loadDefault) {
            if (callback) {
                this.once('sync', callback);
            }

            if (!disableCache) {
                if (this.loadFromCache(loadDefault)) {
                    this.trigger('sync');

                    return new Promise(resolve => resolve());
                }
            }

            return new Promise(resolve => {
                this.fetch(loadDefault)
                    .then(() => resolve());
            });
        },

        /**
         * Load default-language data from the backend.
         *
         * @returns {Promise}
         */
        loadDefault: function () {
            return this.load(null, false, true);
        },

        /**
         * Load data from the backend.
         *
         * @returns {Promise}
         */
        loadSkipCache: function () {
            return this.load(null, true);
        },

        /**
         * Load default-language data from the backend.
         *
         * @returns {Promise}
         */
        loadDefaultSkipCache: function () {
            return this.load(null, true, true);
        },

        /**
         * @private
         * @param {boolean} loadDefault
         * @returns {Promise}
         */
        fetch: function (loadDefault) {
            return Ajax.getRequest(this.url, {default: loadDefault}).then(data => {
                this.data = data;

                this.storeToCache(loadDefault);
                this.trigger('sync');
            });
        },

        /**
         * Sort a field list by a translated name.
         *
         * @param {string} scope An entity type.
         * @param {string[]} fieldList A field list.
         * @returns {string[]}
         */
        sortFieldList: function (scope, fieldList) {
            return fieldList.sort((v1, v2) => {
                 return this.translate(v1, 'fields', scope)
                     .localeCompare(this.translate(v2, 'fields', scope));
            });
        },

        /**
         * Sort an entity type list by a translated name.
         *
         * @param {string[]} entityList An entity type list.
         * @param {boolean} [plural=false] Use a plural label.
         * @returns {string[]}
         */
        sortEntityList: function (entityList, plural) {
            let category = 'scopeNames';

            if (plural) {
                category += 'Plural';
            }

            return entityList.sort((v1, v2) => {
                 return this.translate(v1, category)
                     .localeCompare(this.translate(v2, category));
            });
        },

        /**
         * Get a value by a path.
         *
         * @param {string[]|string} path A path.
         * @returns {*}
         */
        translatePath: function (path) {
            if (typeof path === 'string' || path instanceof String) {
                path = path.split('.');
            }

            let pointer = this.data;

            path.forEach(key => {
                if (key in pointer) {
                    pointer = pointer[key];
                }
            });

            return pointer;
        },

    }, Backbone.Events);

    return Language;
});