/**
 * Overpass Layer: Rendert Overpass-API-Ergebnisse auf dem CesiumJS-Globus.
 * Nodes als Punkte, Ways als Linien, Relations als Punkte (Center).
 */
const OverpassLayer = {
    _viewer: null,
    _points: null,
    _labels: null,
    _polylines: null,
    _count: 0,
    _data: null,
    _handler: null,
    _nodeIndex: [],
    _currentColor: '#ff9800',

    start(viewer) {
        if (this._points) return;
        this._viewer = viewer;
        this._points = viewer.scene.primitives.add(new Cesium.PointPrimitiveCollection());
        this._labels = viewer.scene.primitives.add(new Cesium.LabelCollection());
        this._polylines = viewer.scene.primitives.add(new Cesium.PolylineCollection());
        this._setupClickHandler();
    },

    stop() {
        if (this._handler) { this._handler.destroy(); this._handler = null; }
        if (this._points && this._viewer) { this._viewer.scene.primitives.remove(this._points); this._points = null; }
        if (this._labels && this._viewer) { this._viewer.scene.primitives.remove(this._labels); this._labels = null; }
        if (this._polylines && this._viewer) { this._viewer.scene.primitives.remove(this._polylines); this._polylines = null; }
        this._count = 0;
        this._data = null;
        this._nodeIndex = [];
        var countEl = document.getElementById('count-overpass');
        if (countEl) countEl.textContent = '-';
    },

    clear() {
        if (this._points) this._points.removeAll();
        if (this._labels) this._labels.removeAll();
        if (this._polylines) this._polylines.removeAll();
        this._count = 0;
        this._data = null;
        this._nodeIndex = [];
        var countEl = document.getElementById('count-overpass');
        if (countEl) countEl.textContent = '-';
    },

    setColor(hexColor) {
        this._currentColor = hexColor || '#ff9800';
    },

    render(data) {
        this.clear();
        if (!this._points) return;
        this._data = data;
        var color = Cesium.Color.fromCssColorString(this._currentColor);
        var colorDim = color.withAlpha(0.6);

        // Nodes
        var nodes = data.nodes || [];
        for (var i = 0; i < nodes.length; i++) {
            var n = nodes[i];
            if (!n.lat || !n.lon) continue;
            this._points.add({
                position: Cesium.Cartesian3.fromDegrees(n.lon, n.lat, 0),
                pixelSize: 7,
                color: color,
                outlineColor: Cesium.Color.BLACK,
                outlineWidth: 1,
            });
            this._nodeIndex.push({ lat: n.lat, lon: n.lon, tags: n.tags, name: n.name, type: 'node' });
            if (n.name) {
                this._labels.add({
                    position: Cesium.Cartesian3.fromDegrees(n.lon, n.lat, 0),
                    text: n.name,
                    font: '10px monospace',
                    fillColor: color.withAlpha(0.8),
                    outlineColor: Cesium.Color.BLACK,
                    outlineWidth: 2,
                    style: Cesium.LabelStyle.FILL_AND_OUTLINE,
                    pixelOffset: new Cesium.Cartesian2(6, -4),
                    scale: 0.7,
                    distanceDisplayCondition: new Cesium.DistanceDisplayCondition(0, 500000),
                });
            }
        }

        // Ways
        var ways = data.ways || [];
        for (var j = 0; j < ways.length; j++) {
            var w = ways[j];
            if (w.geometry && w.geometry.length > 1) {
                var positions = [];
                for (var k = 0; k < w.geometry.length; k++) {
                    var g = w.geometry[k];
                    if (g.lat && g.lon) {
                        positions.push(Cesium.Cartesian3.fromDegrees(g.lon, g.lat, 0));
                    }
                }
                if (positions.length > 1) {
                    this._polylines.add({
                        positions: positions,
                        width: 2.5,
                        material: Cesium.Material.fromType('Color', { color: colorDim }),
                    });
                }
            }
            if (w.lat && w.lon) {
                this._points.add({
                    position: Cesium.Cartesian3.fromDegrees(w.lon, w.lat, 0),
                    pixelSize: 5,
                    color: colorDim,
                });
                this._nodeIndex.push({ lat: w.lat, lon: w.lon, tags: w.tags, name: w.name, type: 'way' });
                if (w.name) {
                    this._labels.add({
                        position: Cesium.Cartesian3.fromDegrees(w.lon, w.lat, 0),
                        text: w.name,
                        font: '10px monospace',
                        fillColor: color.withAlpha(0.7),
                        outlineColor: Cesium.Color.BLACK,
                        outlineWidth: 2,
                        style: Cesium.LabelStyle.FILL_AND_OUTLINE,
                        pixelOffset: new Cesium.Cartesian2(6, -4),
                        scale: 0.7,
                        distanceDisplayCondition: new Cesium.DistanceDisplayCondition(0, 500000),
                    });
                }
            }
        }

        // Relations (Center-Punkt)
        var rels = data.relations || [];
        for (var m = 0; m < rels.length; m++) {
            var r = rels[m];
            if (!r.lat || !r.lon) continue;
            this._points.add({
                position: Cesium.Cartesian3.fromDegrees(r.lon, r.lat, 0),
                pixelSize: 9,
                color: color,
                outlineColor: color.withAlpha(0.3),
                outlineWidth: 3,
            });
            this._nodeIndex.push({ lat: r.lat, lon: r.lon, tags: r.tags, name: r.name, type: 'relation' });
            if (r.name) {
                this._labels.add({
                    position: Cesium.Cartesian3.fromDegrees(r.lon, r.lat, 0),
                    text: r.name,
                    font: '11px monospace',
                    fillColor: color,
                    outlineColor: Cesium.Color.BLACK,
                    outlineWidth: 2,
                    style: Cesium.LabelStyle.FILL_AND_OUTLINE,
                    pixelOffset: new Cesium.Cartesian2(8, -6),
                    scale: 0.8,
                    distanceDisplayCondition: new Cesium.DistanceDisplayCondition(0, 800000),
                });
            }
        }

        this._count = nodes.length + ways.length + rels.length;
        var countEl = document.getElementById('count-overpass');
        if (countEl) countEl.textContent = this._count.toLocaleString('de-DE');
    },

    _setupClickHandler() {
        var self = this;
        this._handler = new Cesium.ScreenSpaceEventHandler(this._viewer.scene.canvas);
        this._handler.setInputAction(function(click) {
            if (!self._nodeIndex.length) return;
            var cart = self._viewer.scene.pickPosition(click.position);
            if (!cart) {
                var ray = self._viewer.scene.camera.getPickRay(click.position);
                cart = self._viewer.scene.globe.pick(ray, self._viewer.scene);
            }
            if (!cart) return;
            var c = Cesium.Cartographic.fromCartesian(cart);
            var lat = Cesium.Math.toDegrees(c.latitude);
            var lon = Cesium.Math.toDegrees(c.longitude);

            var best = null, bd = 999;
            for (var i = 0; i < self._nodeIndex.length; i++) {
                var el = self._nodeIndex[i];
                var d = Math.abs(el.lat - lat) + Math.abs(el.lon - lon);
                if (d < bd) { bd = d; best = el; }
            }
            if (best && bd < 0.3) {
                var name = best.name || 'Unbenannt';
                var typeLabels = { node: 'Node', way: 'Way', relation: 'Relation' };
                var tagsHtml = '';
                var tags = best.tags || {};
                var tagKeys = Object.keys(tags);
                for (var t = 0; t < tagKeys.length && t < 20; t++) {
                    var key = tagKeys[t];
                    tagsHtml += '<tr><td style="color:#00ff88;padding:2px 8px 2px 0">' + key + '</td>' +
                        '<td style="color:#ccc">' + tags[key] + '</td></tr>';
                }
                self._viewer.trackedEntity = undefined;
                self._viewer.selectedEntity = new Cesium.Entity({
                    name: name,
                    description: '<div style="font-family:monospace;font-size:12px;padding:8px;color:#e8eaf0">' +
                        '<div style="font-size:10px;color:#888;margin-bottom:4px">' + typeLabels[best.type] + ' | OpenStreetMap</div>' +
                        '<strong style="color:' + self._currentColor + ';font-size:14px">' + name + '</strong>' +
                        '<table style="margin-top:8px;border-collapse:collapse;width:100%">' + tagsHtml + '</table></div>',
                });
            }
        }, Cesium.ScreenSpaceEventType.LEFT_CLICK);
    },

    getCount: function() { return this._count; },
};