@geogirafe/lib-geoportal/tools/selection/selectionmanager.js

GeoGirafe is a flexible application to build online geoportals.

// SPDX-License-Identifier: Apache-2.0
import GirafeSingleton from '../../base/GirafeSingleton.js';
import { SelectionMode } from '../../models/selection.js';
import { applyFeaturesToSelection } from '../utils/utils.js';
/**
 * Handles the feature selection, independently from the map (2D or 3D) the selection was triggered from.
 * The selection is done in two steps:
 * 1. `select()` asks every layer manager to add its own <code>SelectionParam</code> to the state.
 * 2. The change of <code>selection.selectionParameters</code> triggers the effective query
 *    (WMS GetFeatureInfo and WFS GetFeature) and writes the resulting features into the state.
 */
export default class SelectionManager extends GirafeSingleton {
    get state() {
        return this.context.stateManager.state;
    }
    initializeSingleton() {
        this.context.stateManager.subscribe('selection.selectionParameters', (_, newParams) => {
            // The querying is asynchronous and nobody awaits it here,
            // so a failing request must not end up in an unhandled rejection.
            this.onSelectFeatures(newParams).catch((error) => console.error('Could not select the features.', error));
        });
    }
    /**
     * Selects all the features of the queryable layers that are inside the given extent.
     * Layers selectable today are WMS, WMTS (with wms layer) and Local files.
     */
    select(extent) {
        // Reset current selection if SelectionMode is Replace
        if (this.state.selection.selectionMode === SelectionMode.Replace) {
            this.selectNone();
        }
        else if (this.state.selection.selectionMode === SelectionMode.Add) {
            this.state.selection.selectionParameters = [];
        }
        // Use batch for changes to prevent multiple selection of objects
        this.context.stateManager.batchChanges(() => {
            this.context.wmsManager.selectFeatures(extent);
            this.context.wmtsManager.selectFeatures(extent);
            this.context.localFileManager.selectFeatures(extent);
        });
    }
    selectNone() {
        this.state.selection.selectedFeatures = [];
        this.state.selection.selectionParameters = [];
        this.state.selection.highlightedFeatures = [];
    }
    async onSelectFeatures(selectionParams) {
        if (selectionParams.length === 0) {
            return;
        }
        this.state.loading = true;
        try {
            // WMS GetFeatureInfo
            const wmsPromises = selectionParams.map((param) => {
                const wmsGetFeatureInfoSelectionParam = param.clone((l) => l.queryable && l.wmsQueryableOnly);
                const client = this.context.wmsManager.getClient(wmsGetFeatureInfoSelectionParam.ogcServer);
                return client.getFeatureInfo(wmsGetFeatureInfoSelectionParam);
            });
            // WFS GetFeature
            const wfsPromises = selectionParams.map((param) => {
                const wfsGetFeatureInfoSelectionParam = param.clone((l) => l.wfsQueryable);
                const client = this.context.wfsManager.getClient(wfsGetFeatureInfoSelectionParam.ogcServer);
                const features = client.getFeature(wfsGetFeatureInfoSelectionParam);
                return features;
            });
            const wmsGmlFeatures = (await Promise.all(wmsPromises)).flat();
            const wfsGmlFeatures = (await Promise.all(wfsPromises)).flat();
            const gmlFeatures = [...wmsGmlFeatures, ...wfsGmlFeatures];
            if (gmlFeatures.length === 0 && this.state.selection.selectedFeatures.length === 0) {
                this.state.interface.selectionComponentVisible = false;
            }
            else {
                applyFeaturesToSelection(gmlFeatures, this.state);
            }
        }
        finally {
            this.state.loading = false;
        }
    }
}