require('ol/ol.css');

const axios = require('axios');
const {Map, View} = require('ol');

const TileLayer = require('ol/layer/Tile').default;
const XYZSource = require('ol/source/XYZ').default;

const VectorLayer = require('ol/layer/Vector').default;
const VectorSource = require('ol/source/Vector').default;

const Feature = require('ol/Feature').default;
const Point = require('ol/geom/Point').default;
const LineString = require('ol/geom/LineString').default;

const proj = require('ol/proj');

const {Style, Fill, Stroke, Circle} = require('ol/style');
const color = require('color');

const mapboxToken = `pk.eyJ1IjoibWF0dGVvZGVsYWJyZSIsImEiOiJja2NxaTUyMmUwcmFhMn\
h0NmFsdzQ3emxqIn0.cyxF0h36emIMTk3cc4VqUw`;

const network = require('../back/data/network.json');

const makeDataSources = async () =>
{
    const segmentsSource = new VectorSource();
    const stopsSource = new VectorSource();

    segmentsSource.addFeatures(
        Object.values(network.segments).map(({lines, points}) =>
            new Feature({
                colors: lines.map(line => network.lines[line].color),
                geometry: new LineString(points.map(
                    ({lat, lon}) => proj.fromLonLat([lon, lat])
                )),
            })
        )
    );

    stopsSource.addFeatures(
        Object.values(network.stops).map(({lines, lon, lat}) =>
            new Feature({
                colors: lines.map(line => network.lines[line].color),
                geometry: new Point(proj.fromLonLat([lon, lat])),
            })
        )
    );

    return {segmentsSource, stopsSource};
};

const makeBorderColor = mainColor =>
{
    const hsl = color(mainColor).hsl();
    hsl.color = Math.max(0, hsl.color[2] -= 20);
    return hsl.hex();
};

const segmentsBorderStyle = feature => new Style({
    stroke: new Stroke({
        color: makeBorderColor(feature.get('colors')[0]),
        width: 8,
    }),
});

const segmentsInnerStyle = feature => new Style({
    stroke: new Stroke({
        color: feature.get('colors')[0],
        width: 6,
    }),
});

const stopsStyle = feature => new Style({
    image: new Circle({
        fill: new Fill({
            color: feature.get('colors')[0],
        }),
        stroke: new Stroke({
            color: makeBorderColor(feature.get('colors')[0]),
            width: 1.5,
        }),
        radius: 6,
    }),
});

const createMap = async (target) =>
{
    // Map background
    const backgroundSource = new XYZSource({
        url: 'https://api.mapbox.com/' + [
            'styles', 'v1', 'mapbox', 'streets-v11',
            'tiles', '512', '{z}', '{x}', '{y}',
        ].join('/') + `?access_token=${mapboxToken}`,
        tileSize: [512, 512],
    });

    const backgroundLayer = new TileLayer({
        source: backgroundSource,
    });

    // Data overlay
    const {segmentsSource, stopsSource} = await makeDataSources();

    const segmentsBorderLayer = new VectorLayer({
        source: segmentsSource,
        style: segmentsBorderStyle,

        updateWhileInteracting: true,
        updateWhileAnimating: true,
    });

    const segmentsInnerLayer = new VectorLayer({
        source: segmentsSource,
        style: segmentsInnerStyle,

        updateWhileInteracting: true,
        updateWhileAnimating: true,
    });

    const stopsLayer = new VectorLayer({
        source: stopsSource,
        style: stopsStyle,

        minZoom: 13,
        updateWhileInteracting: true,
        updateWhileAnimating: true,
    });

    // Setup map
    const map = new Map({
        target,
        layers: [
            backgroundLayer,
            segmentsBorderLayer,
            segmentsInnerLayer,
            stopsLayer,
        ],
        view: new View({
            center: proj.fromLonLat([3.88, 43.605]),
            zoom: 13,
            maxZoom: 22,
            constrainResolution: true,
        }),
    });

    return map;
};

exports.createMap = createMap;