define([
    'base/js/namespace',
    'jquery'
], function(
    Jupyter,
    $
) {
    var mod_name = "mickaSearch";
    var log_prefix = '[' + mod_name + '] ';
    var cfg = {
        'window_display': false,
        'csw_url': 'https://hub.lesprojekt.cz/micka/micka2/csw/',
        'proxy_url': ''
    };

    var read_config = function () {
        var config = IPython.notebook.config;
        for (var key in cfg) {
            if (config.data.mickaSearch.hasOwnProperty(key))
                cfg[key] = config.data.mickaSearch[key];
        }
    };

    var fetch_metatada = function (search_params) {
        return fetch(`${cfg.proxy_url}${cfg.csw_url}${search_params}`);
    };

    var initialize = function () {
        read_config();

        var handler = function () {
            mdata = fetch_metatada('?request=GetRecords&query=&format=application/json&MaxRecords=9999&StartPosition=&sortby=title%3AA&language=eng&outputSchema=http://www.w3.org/2005/Atom');
            mdata.then(response => response.json())
            .then(arrayOfMetadata => {
                console.log(arrayOfMetadata);
                alert(arrayOfMetadata.records[0].id);
            })
            .catch(error => {
                console.log(error);
            });
        };

        var action = {
            icon: 'fa-search', // a font-awesome class used on buttons, etc
            help    : 'Micka Search',
            help_index : 'zz',
            label: 'Micka',
            handler : handler
        };
        var prefix = 'micka_search';
        var action_name = 'micka-search';

        var full_action_name = Jupyter.actions.register(action, action_name, prefix);
        Jupyter.toolbar.add_buttons_group([full_action_name]);
        console.log(log_prefix + 'button added');
    }

    var load_ipython_extension = function() {
        return IPython.notebook.config.loaded.then(initialize);
    };

    return {
        load_ipython_extension: load_ipython_extension
    };
});