const fragment = location.hash.substring(1);

const i = fragment.indexOf('&');
let latlon;
let params;
if (i != -1) {
    latlon = fragment.slice(0, i);
    params = Object.fromEntries(new URLSearchParams(fragment.slice(i+1)).entries());
} else {
    latlon = fragment;
    params = {};
}

const [lat, lon] = latlon.split(',');

function getLinks(lat, lon, zoom) {
    return [
        {
            label: 'Google Maps',
            url: `https://www.google.com/maps/search/?api=1&query=${lat},${lon}`,
        },
        {
            label: 'Apple Maps',
            url: `https://maps.apple.com/?q=${lat},${lon}&t=m`
        },
        {
            label: 'Default app',
            url: `geo:${lat},${lon}`
        },
        {
            label: 'OpenStreetMap',
            url: `https://www.openstreetmap.org/?mlat=${lat}&mlon=${lon}&zoom=${zoom}&layers=M`
        },
    ]
}

const heading = document.getElementById('heading');

// TODO: listen on hashChange

if (isNaN(lat) || isNaN(lon)) {
    heading.textContent = 'not yet implemented';
} else {
    const zoom = params.z || 15;
    const linkList = document.getElementById('links');
    document.getElementById('instructions').hidden = false;

    if (params.name) {
        document.title = params.name;
        heading.textContent = params.name;
    }

    for (const link of getLinks(lat, lon, zoom)) {
        const li = document.createElement('li');
        const a = document.createElement('a');
        a.href = link.url;
        a.textContent = link.label;
        li.appendChild(a);
        linkList.appendChild(li);
    }
}