const minZoomForRequest = 17;
let markers = [];
function initMap(btn) {
    // Init map position/zoom. Potentially using what's in the URL search string.
    const params = new URLSearchParams(window.location.search);
    let x = parseFloat(params.get('x'));
    let y = parseFloat(params.get('y'));
    let z = parseInt(params.get('z'));
    let map = L.map('map');
    if(x && y && z) {
        map.setView([y, x], z);
        fetchEligData(map);
        displayBtn(btn);
    } else {
        map.setView([46.710, 3.669], 6);
    }

    L.tileLayer('https://{s}.tile.openstreetmap.fr/osmfr/{z}/{x}/{y}.png', {
        attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
    }).addTo(map);

    map.on("zoom", () => {
        /* We only want to enable the search button when we reached a sufficient zoom level */
        if (btn.disabled && map.getZoom() >= minZoomForRequest) {
            displayBtn(btn);
        }
        if (!btn.disabled && map.getZoom() < minZoomForRequest) {
            hideBtn(btn);
        }
    });
    return map;
}

function initAddrSearch(map) {
    const autocompleteOptions = {
        debounceTime: 300,
        search: async (query) => {
            if(query.length > 2) {
                const mapCenter = map.getCenter();
                const reqUri = `https://photon.komoot.io/api/?q=${encodeURI(query)}&lat=${mapCenter.lat}&lon=${mapCenter.lng}&limit=20&lang=fr`;
                const source = await fetch(reqUri);
                const data = await source.json();
                return data.features;
            } else {
                return [];
            }
        },
        renderResult: (res, props) => {
            const p = res.properties;
            if(p.name && p.postcode && p.city && p.county && res.geometry.coordinates && res.geometry.coordinates.length === 2)
                return `<li ${props}>${p.name} - ${p.postcode} ${p.city}, ${p.county}</li>`;
            else
                return "";
        },
        onSubmit: async (res) => {
            const searchInput = document.getElementById('search-addr-autocomplete-input');
            const p = res.properties;
            searchInput.value = `${p.name} - ${p.postcode} ${p.city}, ${p.county}`;
            // We already filtered out the result not having strictly 2 coordinates at item display
            map.setView([res.geometry.coordinates[1],res.geometry.coordinates[0]], 19);
            fetchEligData(map);
        }
    };
    const autocompleteAddr = new Autocomplete("#search-addr-autocomplete", autocompleteOptions);
    return autocompleteAddr;
}

function updateEligData(map, eligData) {
    markers.map(marker => map.removeLayer(marker));
    let buildings = eligData.buildings;
    markers = buildings.map(building => {
        const latlng = new L.latLng(building.y, building.x);
        const addrImm = `${building.numVoieImm} ${building.typeVoieImm} ${building.nomVoieImm}`
        const marker = new L.marker(latlng)
              .bindPopup(`${addrImm}<br/>Etat: ${building.etatImm}<br/>Code Immeuble: ${building.idImm}`);
        map.addLayer(marker);
        return marker
    });
}

function updateUrl(map) {
    const c = map.getCenter();
    history.replaceState({}, "", encodeURI(`?x=${c.lng}&y=${c.lat}&z=${map.getZoom()}`));
}

async function fetchEligData(map) {
    const zoom = map.getZoom();
    if (zoom >= minZoomForRequest) {
        const bounds = map.getBounds();
        const sw = bounds.getSouthWest();
        const ne = bounds.getNorthEast();
        const reqUri = encodeURI(`eligdata?swx=${sw.lng}&swy=${sw.lat}&nex=${ne.lng}&ney=${ne.lat}`);
        const source = await fetch(reqUri);
        const eligData = await source.json();
        updateEligData(map, eligData);
        updateUrl(map);
    }
}

function initBtn() {
    const btn = document.getElementById("btn-load-elig-data");
    btn.disabled = true;
    btn.title = "Veuillez zoomer plus la carte avant de lancer une recherche d'éligibilité.";
    btn.onclick = () => fetchEligData(map);
    return btn;
}

function displayBtn(btn) {
    btn.disabled = false;
    btn.title = "Rechercher les données d'éligibilité pour cette zone."
}

function hideBtn(btn) {
    btn.disabled = true;
    btn.title = "Veuillez zoomer plus la carte avant de lancer une recherche d'éligibilité.";
}


const btn = initBtn();
const map = initMap(btn);
const addrSearch = initAddrSearch(map);