package map

import javafx.concurrent.Worker
import javafx.scene.layout.StackPane
import javafx.scene.paint.Color
import javafx.scene.shape.Polygon
import javafx.scene.web.WebEngine
import javafx.scene.web.WebView
import map.events.*
import netscape.javascript.JSObject
import java.io.ByteArrayOutputStream
import java.io.File
import java.io.IOException
import java.net.URL
import java.util.*
import java.util.concurrent.CompletableFuture
import javax.imageio.ImageIO


/**
 * JavaFX component for displaying OpenStreetMap based maps by using the Leaflet.js JavaScript library inside a WebView
 * browser component.<br/>
 * This component can be embedded most easily by placing it inside a StackPane, the component uses then the size of the
 * parent automatically.
 *
 * @author Stefan Saring
 * @author Niklas Kellner
 */
class LeafletMapView : StackPane() {

    private val webView = WebView()
    private val webEngine: WebEngine = webView.engine

    private var varNameSuffix: Int = 1
    private val mapClickEvent = MapClickEventMaker()
    private val markerClickEvent = MarkerClickEventMaker()
    private val mapMoveEvent = MapMoveEventMaker()
    internal val zoomLimitSmallMarker = 8

    /**
     * Creates the LeafletMapView component, it does not show any map yet.
     */
    init {
        this.children.add(webView)
    }

    /**
     * Displays the initial map in the web view. Needs to be called and complete before adding any markers or tracks.
     * The returned CompletableFuture will provide the final map load state, the map can be used when the load has
     * completed with state SUCCEEDED (use CompletableFuture#whenComplete() for waiting to complete).
     *
     * @param mapConfig configuration of the map layers and controls
     * @return the CompletableFuture which will provide the final map load state
     */
    fun displayMap(mapConfig: MapConfig): CompletableFuture<Worker.State> {
        val finalMapLoadState = CompletableFuture<Worker.State>()

        webEngine.loadWorker.stateProperty().addListener { _, _, newValue ->

            if (newValue == Worker.State.SUCCEEDED) {
                executeMapSetupScripts(mapConfig)
            }

            if (newValue == Worker.State.SUCCEEDED || newValue == Worker.State.FAILED) {
                finalMapLoadState.complete(newValue)
            }
        }

        val localFileUrl: URL = LeafletMapView::class.java.getResource("/leafletmap/leafletmap.html")
        webEngine.load(localFileUrl.toExternalForm())
        return finalMapLoadState
    }

    private fun executeMapSetupScripts(mapConfig: MapConfig) {

        // execute scripts for layer definition
        mapConfig.layers.forEachIndexed { i, layer ->
            execScript("var layer${i + 1} = ${layer.javaScriptCode};")
        }

        val jsLayers = mapConfig.layers
            .mapIndexed { i, layer -> "'${layer.displayName}': layer${i + 1}" }
            .joinToString(", ")
        execScript("var baseMaps = { $jsLayers };")

        // execute script for map view creation (Leaflet attribution must not be a clickable link)
        execScript(
            """
                |var myMap = L.map('map', {
                |    center: new L.LatLng(${mapConfig.initialCenter.latitude}, ${mapConfig.initialCenter.longitude}),
                |    zoom: 1,
                |    zoomControl: false,
                |    layers: [layer1]
                |});
                |L.control.scale().addTo(myMap);
                |var myRenderer = L.canvas({ padding: 0.5 });
                |var markerClusters = L.markerClusterGroup({spiderfyOnMaxZoom: false, disableClusteringAtZoom: 10});
                |var heatLayer = L.heatLayer([]).addTo(myMap);""".trimMargin()
        )

//        eventZoomChangeIcon()

        // execute script for layer control definition if there are multiple layers
        if (mapConfig.layers.size > 1) {
            execScript(
                """
                    |var overlayMaps = {};
                    |L.control.layers(baseMaps, overlayMaps).addTo(myMap);""".trimMargin()
            )

        }

        // execute script for scale control definition
        if (mapConfig.scaleControlConfig.show) {
            execScript(
                "L.control.scale({position: '${mapConfig.scaleControlConfig.position.positionName}', " +
                        "metric: ${mapConfig.scaleControlConfig.metric}, " +
                        "imperial: ${!mapConfig.scaleControlConfig.metric}})" +
                        ".addTo(myMap);"
            )
        }

        // execute script for zoom control definition
        if (mapConfig.zoomControlConfig.show) {
            execScript(
                "L.control.zoom({position: '${mapConfig.zoomControlConfig.position.positionName}'})" +
                        ".addTo(myMap);"
            )
        }
    }

    /**
     * Sets the view of the map to the specified geographical center position and zoom level.
     *
     * @param position map center position
     * @param zoomLevel zoom level (0 - 19 for OpenStreetMap)
     */
    fun setView(position: LatLong, zoomLevel: Int) =
        execScript("myMap.setView([${position.latitude}, ${position.longitude}], $zoomLevel);")

    /**
     * Pans the map to the specified geographical center position.
     *
     * @param position map center position
     */
    fun panTo(position: LatLong) =
        execScript("myMap.panTo([${position.latitude}, ${position.longitude}]);")

    /**
     * Sets the zoom of the map to the specified level.
     *
     * @param zoomLevel zoom level (0 - 19 for OpenStreetMap)
     */
    fun setZoom(zoomLevel: Int) =
        execScript("myMap.setZoom([$zoomLevel]);")

    /**
     * Adds a Marker Object to a map
     *
     * @param marker the Marker Object
     */
    fun addMarker(marker: Marker) {
        marker.addToMap(getNextMarkerName(), this)
    }

    fun addCircle(circle: Circle) {
        circle.addToMap(this)
    }

    fun addZone(zone: Zone) {
        zone.addToMap(this)
    }

    /**
     * Removes an existing marker from the map
     *
     * @param marker the Marker object
     */
    fun removeMarker(marker: Marker) {
        execScript("myMap.removeLayer(${marker.getName()});")
    }

    fun removeCircle(circle: Circle) {
        circle.removeCircle(this)
    }

    fun removeZone(zone: Zone) {
        zone.removeZone()
    }

    fun removeZone(id: String) {
        val idSanitized = id.replace("-", "")
        execScript("myMap.removeLayer(polygon$idSanitized);")
    }


    fun uppdateCircle(circle: Circle, latLong: LatLong, radius: Double) {
        circle.modifyCircle(latLong, radius)
        circle.uppdateMap()
    }

    fun setEventMousePosition() {
        execScript(
            "var lat=0.0, lng=0.0;\n" +
                    "myMap.addEventListener('mousemove', function(ev) {\n" +
                    "   lat = ev.latlng.lat;\n" +
                    "   lng = ev.latlng.lng;\n" +
                    "});"
        )
    }

    fun getMousePosition(): LatLong {
        val lat = execScript("lat;") as Double
        val lng = execScript("lng;") as Double
        return LatLong(lat, lng)
    }

    /**
     * Adds a custom marker type
     *
     * @param markerName the name of the marker type
     * @param iconUrl the url if the marker icon
     */
    fun addCustomMarker(markerName: String, iconUrl: String): String {
        execScript(
            "var $markerName = L.icon({\n" +
                    "iconUrl: '${createImage(iconUrl, "png")}',\n" +
                    "iconSize: [24, 24],\n" +
                    "iconAnchor: [12, 12],\n" +
                    "});"
        )
        return markerName
    }

    private fun createImage(path: String, type: String): String {
        val image = ImageIO.read(File(path))
        var imageString: String? = null
        val bos = ByteArrayOutputStream()

        try {
            ImageIO.write(image, type, bos)
            val imageBytes = bos.toByteArray()

            val encoder = Base64.getEncoder()
            imageString = encoder.encodeToString(imageBytes)

            bos.close()
        } catch (e: IOException) {
            e.printStackTrace()
        }
        return "data:image/$type;base64,$imageString"
    }

    /**
     * Sets the onMarkerClickListener
     *
     * @param listener the onMarerClickEventListener
     */
    fun onMarkerClick(listener: MarkerClickEventListener) {
        val win = execScript("document") as JSObject
        win.setMember("java", this)
        markerClickEvent.addListener(listener)
    }

    /**
     * Handles the callback from the markerClickEvent
     */
    fun markerClick(title: String) {
        markerClickEvent.MarkerClickEvent(title)
    }

    /**
     * Sets the onMapMoveListener
     *
     * @param listener the MapMoveEventListener
     */
    fun onMapMove(listener: MapMoveEventListener) {
        val win = execScript("document") as JSObject
        win.setMember("java", this)
        execScript("myMap.on('moveend', function(e){ document.java.mapMove(myMap.getCenter().lat, myMap.getCenter().lng);});")
        mapMoveEvent.addListener(listener)
    }

    /**
     * Handles the callback from the mapMoveEvent
     */
    fun mapMove(lat: Double, lng: Double) {
        val latlng = LatLong(lat, lng)
        mapMoveEvent.MapMoveEvent(latlng)
    }

    /**
     * Sets the onMapClickListener
     *
     * @param listener the onMapClickEventListener
     */
    fun onMapClick(listener: MapClickEventListener) {
        val win = execScript("document") as JSObject
        win.setMember("java", this)
        execScript("myMap.on('click', function(e){ document.java.mapClick(e.latlng.lat, e.latlng.lng);});")
        mapClickEvent.addListener(listener)
    }

    /**
     * Handles the callback from the mapClickEvent
     */
    fun mapClick(lat: Double, lng: Double) {
        val latlng = LatLong(lat, lng)
        mapClickEvent.MapClickEvent(latlng)
    }

    /**
     * Draws a track path along the specified positions.
     *
     * @param positions list of track positions
     */
    fun addTrack(positions: List<LatLong>) {

        val jsPositions = positions
            .map { "    [${it.latitude}, ${it.longitude}]" }
            .joinToString(", \n")

        execScript(
            """
            |var latLngs = [
            |$jsPositions
            |];
            |var polyline = L.polyline(latLngs, {color: 'red', weight: 2}).addTo(myMap);""".trimMargin()
        )
    }

    fun clearAllLayer() {
        execScript("""
            myMap.eachLayer(function (layer) {
                map.removeLayer(layer);
            });
        """.trimIndent())
    }

    fun addTrack(positions: List<LatLong>, id: String, color: Color, tooltip: String) {

        val jsPositions = positions
            .map { "    [${it.latitude}, ${it.longitude}]" }
            .joinToString(", \n")

        val cleanTooltip = tooltip.replace("'", "&apos;")
        execScript(
            """
            |var latLngs = [
            |$jsPositions
            |];
            |var color = "rgb(${Math.floor(color.getRed() * 255).toInt()} ,${Math.floor(color.getGreen() * 255)
                .toInt()},${Math.floor(color.getBlue() * 255).toInt()})";
            |var polyline$id = L.polyline(latLngs, {color: color, weight: 2, zIndexOffset: 200}).bindTooltip('$cleanTooltip', {sticky: true}).addTo(trackGroup)""".trimMargin()
        )
    }

    fun makeVesselTrackTransparent(id: String) {
        execScript("polyline$id.setStyle({opacity: 0.5});")
    }

    fun highlightTrack(id: String) {
        execScript("polyline$id.setStyle({weight: 4});")
    }

    fun normalizeVesselTrack(id: String) {
        execScript("polyline$id.setStyle({opacity: 1,weight: 2});")
    }

    fun eventZoomChangeIcon() {
        execScript(
            """
            |myMap.on('zoomend', function() {
                |var currentZoom = myMap.getZoom();
                |if (currentZoom < $zoomLimitSmallMarker) {
                    |markersGroup.eachLayer(function(layer) {
                        return layer.setIcon(aircraftSmallIcon)
                    |});
                |} else {
                    |markersGroup.eachLayer(function(layer) {
                        return layer.setIcon(aircraftIcon)
                    |});
                |}
            |});
        """.trimMargin()
        )
    }

    fun removeTrack(id: String) {
        execScript("myMap.removeLayer(polyline$id);")
    }

    fun fitBoundsMarkers() {
        execScript("setTimeout(() => {myMap.fitBounds(markersGroup.getBounds().pad(0.05));}, 500);")
    }

    fun addZone(polygon: Polygon, id: String, color: Color) {
        val points = polygon.points
        val latLongs = arrayListOf<LatLong>()
        var lat: Double
        var lon = 0.0

        for (i in 0 until points.size) {
            if (i % 2 == 0) {
                lon = points[i]
            } else {
                lat = points[i]
                latLongs.add(LatLong(lat, lon))
            }
        }

        val jsPositions = latLongs
            .map { "    [${it.latitude}, ${it.longitude}]" }
            .joinToString(", \n")
        val idSanitized = id.replace("-", "")
        execScript(
            """
            |var latLngs = [
            |$jsPositions
            |];
            |var color = "rgb(${Math.floor(color.getRed() * 255).toInt()} ,${Math.floor(color.getGreen() * 255)
                .toInt()},${Math.floor(color.getBlue() * 255).toInt()})";
            |var polygon$idSanitized = L.polygon(latLngs, {color: color}).addTo(myMap);""".trimMargin()
        )

    }

    internal fun execScript(script: String) = webEngine.executeScript(script)

    private fun getNextMarkerName(): String = "marker${varNameSuffix++}"
}