const aufgabe3 = async () => {

    const loadData = async () => {
        const loadSeries = async (seriesCode, pageSize = 20) => {
            const values = (await axios.get("https://unstats.un.org/SDGAPI/v1/sdg/Series/Data", {
                params: {
                    seriesCode: seriesCode,
                    pageSize: pageSize
                }
            })).data // getting axios data object
            return values.data // getting api data object (remove paging information)
                .filter(elem => elem.timePeriodStart >= 2015 && elem.timePeriodStart <= 2017)
                .filter(elem => elem.dimensions.Location === "ALLAREA")
        }

        const apiData = await Promise.all([
            loadSeries("SH_H2O_SAFE", 5000),
            loadSeries("SH_SAN_SAFE", 5000)
        ])
        return [...apiData[0], ...apiData[1]]
    }

    const levels = [0, 50, 80, 85, 90, 95, 99, 100]

    const getColor = percentage => {
        switch (true) {
            case percentage > levels[7]:
                return '#800026'
            case percentage > levels[6]:
                return '#BD0026'
            case percentage > levels[5]:
                return '#E31A1C'
            case percentage > levels[4]:
                return '#FC4E2A'
            case percentage > levels[3]:
                return '#FD8D3C'
            case percentage > levels[2]:
                return '#FEB24C'
            case percentage > levels[1]:
                return '#FED976'
            case percentage > levels[0]:
                return '#FFEDA0'
            default:
                return '#ffdea1'
        }
    }

    const map = L.map('suiMap').setView([53.0, 14.0], 4)
    map.addLayer(new L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
        attribution: 'Map data <a href="https://openstreetmap.org">OpenStreetMap</a> contributors',
        minZoom: 1,
        maxZoom: 18
    }))
    let [geojsonData, apiData] = await Promise.all([
        $.getJSON('europe.geo.json'),
        loadData()
    ])

    // Attach api data to geojson
    for (let elem of apiData) {
        const find = geojsonData.features.find(value => {
            return value.properties.name_long.includes(elem.geoAreaName) || elem.geoAreaName.includes(value.properties.name_long)
        })
        if (find) find.properties[elem.series + "_" + elem.timePeriodStart] = elem
    }

    // Add the legend to the map
    const legend = L.control({position: 'bottomright'})

    legend.onAdd = () => {
        const legend = L.DomUtil.create('div', 'info legend')
        const labels = []

        for (let i = 0; i < levels.length; i++) {
            labels.push(
                '<i style="background:' + getColor(levels[i] + 1) + '"></i> '
                + levels[i] + (levels[i + 1] ? '&ndash;' + levels[i + 1] : '+')
            )
        }

        legend.innerHTML = labels.join('<br>')
        return legend
    }

    legend.addTo(map)

    // Control that shows state info on hover
    const info = L.control()

    info.onAdd = () => {
        info._div = L.DomUtil.create('div', 'info')
        info.update()
        return info._div
    }

    info.update = (props = {}, currSeries) => {
        const localProps = props[currSeries]
        info._div.innerHTML = localProps ? `<h5>${localProps.seriesDescription}</h5>` : ''
        if (localProps) {
            let formattedPercentage = new Intl.NumberFormat('de-DE').format(localProps.value)
            info._div.innerHTML += `<b>${props.formal_en}</b><br>${formattedPercentage} &percnt;`
        } else {
            info._div.innerHTML += 'Hover over a country'
        }
    }

    info.addTo(map)

    let layers = {}
    let wantedSeries = [
        {name: "SH_H2O_SAFE_2015", displayName: "drinking water services 2015"},
        {name: "SH_H2O_SAFE_2016", displayName: "drinking water services 2016"},
        {name: "SH_H2O_SAFE_2017", displayName: "drinking water services 2017"},
        {name: "SH_SAN_SAFE_2015", displayName: "sanitation services 2015"},
        {name: "SH_SAN_SAFE_2016", displayName: "sanitation services 2016"},
        {name: "SH_SAN_SAFE_2017", displayName: "sanitation services 2017"},
    ]

    for (let currSeries of wantedSeries) {
        let geoJsonLayer = L.geoJson(geojsonData, {
            style: feature => ({
                stroke: true,
                fill: true,
                fillColor: getColor(feature.properties[currSeries.name].value),
                fillOpacity: 1,
                dashArray: '3',
                weight: 2,
                color: 'black'
            }),
            filter: feature => {
                return feature.properties.hasOwnProperty(currSeries.name)
            },
            onEachFeature: (feature, layer) => {
                layer.on({
                    mouseover: event => {
                        event.target.setStyle({
                            weight: 5,
                            color: '#666',
                            dashArray: '',
                            fillOpacity: 0.7
                        })
                        if (!L.Browser.ie && !L.Browser.opera && !L.Browser.edge) event.target.bringToFront()
                        info.update(feature.properties, currSeries.name)
                    },
                    mouseout: event => {
                        geoJsonLayer.resetStyle(event.target)
                        info.update()
                    },
                    click: event => map.fitBounds(event.target.getBounds())
                })
            }
        })
        layers[currSeries.displayName] = geoJsonLayer
    }

    L.control.layers(layers, null).addTo(map)

}

aufgabe3()