somescript.js

function initMap() {
        var countPerLocation = {"3026": 71, "2022": 3, "5010": 2, "2015": 24, "3067": 2, "3086": 3, "3059": 2, "2046": 1, "2019": 6, "5527": 2, "1009": 1, "4087": 1, "4561": 1, "5577": 1, "1006": 27, "4001": 24, "1079": 21, "3056": 1, "4065": 20, "2075": 4, "4047": 12, "5573": 1, "3054": 24, "4018": 2, "3029": 18, "6091": 4, "4539": 2, "4055": 4, "1042": 6, "2013": 1, "4041": 2, "3033": 1, "5081": 1, "2051": 1, "1078": 1, "5070": 1, "5594": 2, "1004": 1, "4044": 1, "3068": 1, "3035": 5};
        var region = 'district';
        maxCount = 0;
        var countPerLocationArray = [];
        for (locationUid in countPerLocation) {
            maxCount = Math.max( maxCount , countPerLocation[locationUid] );
            countPerLocationArray.push(countPerLocation[locationUid]);
        }

        var sort_unique = function(arr) {
            if (arr.length === 0) return arr;
            arr = arr.sort(function (a, b) { return a*1 - b*1; });
            var ret = [arr[0]];
            for (var i = 1; i < arr.length; i++) { //Start loop at 1: arr[0] can never be a duplicate
                if (arr[i-1] !== arr[i]) {
                ret.push(arr[i]);
                }
            }
            return ret;
        }
        var uniqueCountPerLocationSortedData = sort_unique(countPerLocationArray);

        var geojsonData;
        if( region == 'thana' ){
            geojsonData = allThanaGeojson;
        }else{
            geojsonData = allDistrictGeojson;
        }


        var legendColors = [ "#FFEE00", "#FFD509", "#FFBC12", "#FFA31B", "#FF8A24", "#FF712D", "#FF5836", "#FF4040", "#EB3636", "#D72D2D", "#C32424", "#AF1B1B", "#9B1212", "#870909", "#730000"];

        var calculateDensity = function(count){
            var bucketSize = Math.floor(uniqueCountPerLocationSortedData.length / legendColors.length);
            var uniqueIndex = uniqueCountPerLocationSortedData.indexOf(count);
            //console.log(uniqueIndex);
            var colorIndex = Math.floor(uniqueIndex/bucketSize);
            if(bucketSize === 0)
                return uniqueIndex;
            else if(colorIndex >= legendColors.length)
                return legendColors.length-1;

            return colorIndex;
        }

        $.map(geojsonData['features'], function(feature){
            count = 0;
            if( countPerLocation[feature.properties.uid] ){
                count = countPerLocation[feature.properties.uid];
            }
            //feature['properties']['density'] = count / maxCount;
            feature['properties']['density'] = calculateDensity(count);
            feature['properties']['count'] = count;

        });


        var map = L.map('map').setView([23.8103, 90.4125], 7);

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


        function getColor(d) {
            return legendColors[d];
        }

        function style(feature) {
            return {
                fillColor: getColor(feature.properties.density),
                weight: 2,
                opacity: 1,
                color: "#fffbcf",
                dashArray: '3',
                fillOpacity: 0.7
            };
        }

        var geojson;
        var info = L.control();

        info.onAdd = function (map) {
            this._div = L.DomUtil.create('div', 'info'); // create a div with a class "info"
            this.update();
            return this._div;
        };


        info.update = function (props) {
            this._div.innerHTML = '<h4>তথ্য</h4>' +  (props ?
                '<b>' + props.name + '</b><br />' + props.count + ' '
                : 'এলাকাভিত্তিক সংখ্যা দেখার জন্য,<br/>ম্যাপের নির্দিষ্ট জায়গা বরাবর মাউস নিয়ে যান');
        };

        info.addTo(map);

        function highlightFeature(e) {
            var layer = e.target;

            layer.setStyle({
                weight: 2,
                color: '#666',
                dashArray: '',
                fillOpacity: 0.7
            });

            if (!L.Browser.ie && !L.Browser.opera && !L.Browser.edge) {
                layer.bringToFront();
            }
            info.update(layer.feature.properties);
        }

        function resetHighlight(e) {
            geojson.resetStyle(e.target);
            info.update();
        }
        function zoomToFeature(e) {
            //map.fitBounds(e.target.getBounds());
        }

        function onEachFeature(feature, layer) {
            layer.on({
                mouseover: highlightFeature,
                mouseout: resetHighlight,
                click: zoomToFeature
            });
        }

        geojson = L.geoJson(geojsonData, {
            style: style,
            onEachFeature: onEachFeature
        }).addTo(map);



        $.map(geojsonData['features'], function(feature){
            if( feature.properties.count == 0 ){
                return;
            }
            districtInfo = allDistrictInformation[ feature.properties.uid ]

            var textLatLng = [ districtInfo.lat , districtInfo.long  ];
            var myTextLabel = L.marker(textLatLng, {
                icon: L.divIcon({
                    className: 'text-labels',   // Set class for CSS styling
                    html: feature.properties.count
                }),
                zIndexOffset: 1000     // Make appear above other map features
            }).addTo(map);

        });


        /*
        var legend = L.control({position: 'bottomright'});
        legend.onAdd = function (map) {

            var div = L.DomUtil.create('div', 'info legend'),
                grades = [0, 10, 20, 50, 100, 200, 500, 1000],
                labels = [];

            // loop through our density intervals and generate a label with a colored square for each interval
            for (var i = 0; i < grades.length; i++) {
                div.innerHTML +=
                    '<i style="background:' + getColor(grades[i] + 1) + '"></i> ' +
                    grades[i] + (grades[i + 1] ? '&ndash;' + grades[i + 1] + '<br>' : '+');
            }

            return div;
        };

        legend.addTo(map);
        */


    }