// rivet
var filter = {city:'London', country:null, mode:'qmprice'};
filter['countries'] = Array.from(new Set(data.features.map(function(d){return d['properties']['country']})));
rivets.bind(document.getElementById('overlay'), {filter: filter});


function clone(d){
    return JSON.parse(JSON.stringify(d));
}

function percentile(arr, p) {
    if (arr.length === 0) return 0;
    if (typeof p !== 'number') throw new TypeError('p must be a number');
    if (p <= 0) return arr[0];
    if (p >= 1) return arr[arr.length - 1];

    var index = arr.length * p,
        lower = Math.floor(index),
        upper = lower + 1,
        weight = index % 1;

    if (upper >= arr.length) return arr[lower];
    return arr[lower] * (1 - weight) + arr[upper] * weight;
}

function update(){
    // close overlay
    var modal = document.getElementById('modal_overlay');
    modal.classList.toggle('modal-open');

    // init heatmap
    heatmap = new HexgridHeatmap(map, "hexgrid-heatmap", "waterway-label");
    heatmap.setIntensity(6); // dunno yet
    heatmap.setSpread(0.15); // dunno yet
    heatmap.setCellDensity(0.5); // small value == bigger hexagons
    heatmap.setPropertyName(filter.mode);


    // set filter
    if(filter.city){
        cityDim.filterExact(filter.city);
    } else if(filter.country){
        countryDim.filterExact(filter.country);
    }else{
        alert('nothing loadable');
    }
    filter.count = cityDim.top(Infinity).length;

    var subset = {"type": "FeatureCollection", "features": []};
    indexDim.top(Infinity).forEach(function(i){
        subset.features.push(data.features[i.index]);
    });

    loadData(subset);
}

function loadData(subset){
    heatmap.setData(subset);
    var values = subset.features.map(function(d){return d['properties'][filter.mode]});
    values = values.sort(function(a,b){return a-b;});

    // setting the color stops, min is at 5th percentile, max at 95percentile
    var min =  values[Math.round(values.length * 0.05)];
    var max =  values[Math.round(values.length * 0.95)];
    var colorStopsPerc = [
        [0, "rgba(0,185,243,0)"],
        [25, "rgba(0,185,243,0.24)"],
        [60, "rgba(255,223,0,0.3)"],
        [100, "rgba(255,105,0,0.3)"],
    ];
    makeLegend(colorStopsPerc, min, max);
    var colorStopsValue = colorStopsPerc.map(function(d){
        return [min + d[0]*(max-min)/100, d[1]];
    });
    heatmap.setColorStops(colorStopsValue);
    heatmap.update();

    //get bounding box and zoom to that area
    // we use a 1% percentile since some data can be corrupt
    var longitudes = subset.features.map(function(d){return d.geometry.coordinates[0];}).sort(function(a,b){return a-b;});
    var latitudes = subset.features.map(function(d){return d.geometry.coordinates[1];}).sort(function(a,b){return a-b;});
    var minlng = percentile(longitudes, 0.01);
    var maxlng = percentile(longitudes, 0.99);
    var minlat = percentile(latitudes, 0.01);
    var maxlat = percentile(latitudes, 0.99);
    map.fitBounds([
        [minlng, minlat],
        [maxlng, maxlat]
    ]);
}

mapboxgl.accessToken = 'pk.eyJ1IjoiZGktdG8iLCJhIjoiY2o0bnBoYXcxMW1mNzJ3bDhmc2xiNWttaiJ9.ZccatVk_4shzoAsEUXXecA';
var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/light-v9',
    center: [13.38032, 49.994210],
    zoom: 5
});


map.on("load", function(){
    var crossData = data.features.map(function(d, i){
        //clone properties
        var props = clone(d['properties']);
        props['index'] = i;
        return props;
    });
    cf = crossfilter(crossData);
    qmDim = cf.dimension(function(d){return d.qm;});
    cityDim = cf.dimension(function(d){return d.city;});
    countryDim = cf.dimension(function(d){return d.country;});
    rentDim = cf.dimension(function(d){return d.total_price;});
    roomsDim = cf.dimension(function(d){return d.rooms;});
    indexDim = cf.dimension(function(d){return d.index;});
});

// map.addInteraction('my-polygon-click-interaction', {
//   type: 'click',
//   target: 'polygons',
//   handler: (e) => {
//     console.log('Polygon clicked:', e.feature);
//     map.setFeatureState(e.feature, {highlight: true});
//   }
// });



function makeLegend(colorstops, minValue, maxValue){
    /**
     * colorstops: [[0, 'green'], [100, 'red']]
     * @type {number}
     */
    var svg_height = 300, svg_width=70;
    var svg = d3.select('#svg');
    var defs = svg
        .attr('height', svg_height)
        .attr('width', svg_width);

    var linearGradient = svg.append("defs")
        .append("linearGradient")
        .attr("id", "linear-gradient");

    linearGradient
        .attr("x1", "0%")
        .attr("y1", "100%")
        .attr("x2", "0%")
        .attr("y2", "0%");

    svg.append("rect")
        .attr("width", svg_width*0.4)
        .attr("height", svg_height)
        .attr('rx', 4)
        .style("fill", "url(#linear-gradient)");

    colorstops.forEach(function(d){
        linearGradient.append("stop")
            .attr("offset", d[0] + "%")
            .attr("stop-color", d[1]);
    });


    var xScale = d3.scaleLinear().range([svg_height-20,0]).domain([minValue,maxValue]);
    var xAxis = d3.axisRight(xScale).ticks(5);

    svg.append("g")
        .attr("class", "axis")
        .attr("transform", "translate("+svg_width/2+"," + (10) + ")")
        .call(xAxis);
}