(function() {
    const MIN_ZOOM = 6;
    const MAX_ZOOM = 18;
    const INITIAL_ZOOM = 14;

    const TILE_URL = 'https://{s}.tile.openstreetmap.fr/osmfr/{z}/{x}/{y}.png';

    const STATE = {
        locations: new Map(),
    };

    let db = new Kinto({
        bucket: "magellan"
    });
    let kintoLocations = db.collection("locations");
    let syncOptions = {
        remote: "https://kinto.b.delire.party/v1",
        //headers: {Authorization: "Basic " + btoa('user:pass')}
    };

    async function sync() {
        try {
            await kintoLocations.sync(syncOptions);
        } catch (err){
            alert(err);
        }
    }

    sync();

    function addLocation(loc) {
        if (!STATE.locations.has(loc.label)) {
            let marker = L.marker(loc.coordinates)
                .addTo(map)
                .bindPopup(loc.label);
            STATE.locations.set(loc.label, marker);
            return true;
        }
        return false;
    }

    async function init() {
        try {
            let locations = await kintoLocations.list();
            locations = locations.data;
            console.log(locations)
            locations.forEach(addLocation);
        } catch (err) {
            alert(`on init: ${err.toString()}`)
        }
    }
    init();

    async function addNewLocation(loc) {
        if (addLocation(loc)) {
            let marker = STATE.locations.get(loc.label);
            marker.openPopup();

            // Add it to kinto.
            try {
                await kintoLocations.create({
                    label: loc.label,
                    coordinates: loc.coordinates
                });
            } catch (err) {
                alert(`Error when creating new location: ${err.toString()}`);
            };

            sync();
        } else {
            STATE.locations.get(loc.label).openPopup();
        }
    }

    class Location {
        constructor({ id, label, coordinates}) {
            this.id = id || null;
            this.label = label;
            this.coordinates = coordinates;
        }
    }

    async function fetchLocation(address) {
        // Alternatively, search only for addresses (specialized for Lyon 7).
        //const GEOCODING_URL = 'https://api-adresse.data.gouv.fr/search/?q={query}&postcode=69007';

        const GEOCODING_URL = 'https://demo.addok.xyz/search/?q={query}&limit=20';
        let resp = await fetch(GEOCODING_URL.replace('{query}', address));
        let results = await resp.json();

        results = results.features.map(feature => {
            let { properties: {label: label}, geometry: { coordinates: coordinates }} = feature;
            coordinates.unshift(coordinates.pop());
            return new Location({label, coordinates});
        });

        console.log(results);
        return results;
    }

    let map = L.map('the-map').setView([45.751591, 4.845695], INITIAL_ZOOM);

    L.tileLayer(TILE_URL, {minZoom: MIN_ZOOM, maxZoom: MAX_ZOOM, attribution: 'Carte données &copy; <a href="https://osm.org/copyright/">OpenStreetMap (ODbL)</a> / fond OSM-FR (CC-by-SA), <a href="https://www.data.gouv.fr/fr/datasets/points-dinterets-openstreetmap/">POI: OpenStreetMap (ODbL)</a>, <a href="https://www.data.gouv.fr/fr/datasets/base-d-adresses-nationale-ouverte-bano/">adresses BANO (ODbL)</a>, <a href="https://github.com/addok/addok">geocodeur addok</a>'}).addTo(map);

    let $ = document.querySelector.bind(document);
    let $address = $('#address');
    let $submit = $('#submit');
    let $results = window.results = $('#results');

    $('#form').onsubmit = function(event) {
        event.preventDefault();
        return false;
    }

    $submit.onclick = async function() {
        let address = $address.value.trim();

        $results.innerHTML = `searching for ${address}...`;
        let firstResult = true;

        let locations = await fetchLocation(address);
        locations = locations.map(loc => {
            let li = document.createElement('li');

            let a = document.createElement('a');
            a.href = '#';
            a.onclick = function() {
                L.popup()
                    .setLatLng(loc.coordinates)
                    .setContent(loc.label)
                    .openOn(map);
            }
            a.appendChild(document.createTextNode(loc.label))
            li.appendChild(a);

            li.appendChild(document.createTextNode(' '));

            let button = document.createElement('button');
            button.appendChild(document.createTextNode('Save'));
            button.onclick = () => { addNewLocation(loc) };
            li.appendChild(button);

            if (firstResult) {
                firstResult = false;
                $results.innerHTML = '';
            }
            $results.appendChild(li);
            return li;
        });
    }
})();