import { json as d3_json } from 'd3-request';

import { utilQsString } from '../util';


var endpoint = 'https://en.wikipedia.org/w/api.php?';

export default {

    init: function() {},
    reset: function() {},


    search: function(lang, query, callback) {
        if (!query) {
            callback('', []);
            return;
        }

        lang = lang || 'en';
        d3_json(endpoint.replace('en', lang) +
            utilQsString({
                action: 'query',
                list: 'search',
                srlimit: '10',
                srinfo: 'suggestion',
                format: 'json',
                origin: '*',
                srsearch: query
            }), function(err, data) {
                if (err || !data || !data.query || !data.query.search || data.error) {
                    callback('', []);
                } else {
                    var results = data.query.search.map(function(d) { return d.title; });
                    callback(query, results);
                }
            }
        );
    },


    suggestions: function(lang, query, callback) {
        if (!query) {
            callback('', []);
            return;
        }

        lang = lang || 'en';
        d3_json(endpoint.replace('en', lang) +
            utilQsString({
                action: 'opensearch',
                namespace: 0,
                suggest: '',
                format: 'json',
                origin: '*',
                search: query
            }), function(err, data) {
                if (err || !data || data.error) {
                    callback('', []);
                } else {
                    callback(data[0], data[1] || []);
                }
            }
        );
    },


    translations: function(lang, title, callback) {
        if (!title) {
            callback({});
            return;
        }

        d3_json(endpoint.replace('en', lang) +
            utilQsString({
                action: 'query',
                prop: 'langlinks',
                format: 'json',
                origin: '*',
                lllimit: 500,
                titles: title
            }), function(err, data) {
                if (err || !data || !data.query || !data.query.pages || data.error) {
                    callback({});
                } else {
                    var list = data.query.pages[Object.keys(data.query.pages)[0]],
                        translations = {};
                    if (list && list.langlinks) {
                        list.langlinks.forEach(function(d) {
                            translations[d.lang] = d['*'];
                        });
                    }
                    callback(translations);
                }
            }
        );
    }

};