/*
    * Copyright (C) 2022 B3Partners B.V.
    *
    * SPDX-License-Identifier: MIT
    */
   package org.tailormap.api.controller;
   
   import static org.springframework.web.bind.annotation.RequestMethod.GET;
   import static org.springframework.web.bind.annotation.RequestMethod.POST;
  import static org.tailormap.api.persistence.helper.TMAttributeTypeHelper.isGeometry;
  import static org.tailormap.api.persistence.helper.TMFeatureTypeHelper.getConfiguredAttributes;
  
  import io.micrometer.core.annotation.Timed;
  import jakarta.validation.constraints.NotNull;
  import java.io.IOException;
  import java.io.Serializable;
  import java.lang.invoke.MethodHandles;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  import java.util.stream.Collectors;
  import org.apache.commons.lang3.tuple.Pair;
  import org.geotools.api.data.Query;
  import org.geotools.api.data.SimpleFeatureSource;
  import org.geotools.api.feature.simple.SimpleFeature;
  import org.geotools.api.filter.Filter;
  import org.geotools.api.filter.FilterFactory;
  import org.geotools.api.filter.sort.SortOrder;
  import org.geotools.api.referencing.FactoryException;
  import org.geotools.api.referencing.operation.MathTransform;
  import org.geotools.api.referencing.operation.TransformException;
  import org.geotools.data.simple.SimpleFeatureIterator;
  import org.geotools.factory.CommonFactoryFinder;
  import org.geotools.filter.text.cql2.CQLException;
  import org.geotools.filter.text.ecql.ECQL;
  import org.geotools.geometry.jts.JTS;
  import org.geotools.util.factory.GeoTools;
  import org.locationtech.jts.geom.Coordinate;
  import org.locationtech.jts.geom.Geometry;
  import org.locationtech.jts.util.GeometricShapeFactory;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.annotation.Value;
  import org.springframework.http.HttpStatus;
  import org.springframework.http.MediaType;
  import org.springframework.http.ResponseEntity;
  import org.springframework.transaction.annotation.Transactional;
  import org.springframework.validation.annotation.Validated;
  import org.springframework.web.bind.annotation.ModelAttribute;
  import org.springframework.web.bind.annotation.RequestMapping;
  import org.springframework.web.bind.annotation.RequestParam;
  import org.springframework.web.server.ResponseStatusException;
  import org.tailormap.api.annotation.AppRestController;
  import org.tailormap.api.geotools.TransformationUtil;
  import org.tailormap.api.geotools.featuresources.FeatureSourceFactoryHelper;
  import org.tailormap.api.geotools.processing.GeometryProcessor;
  import org.tailormap.api.persistence.Application;
  import org.tailormap.api.persistence.GeoService;
  import org.tailormap.api.persistence.TMFeatureType;
  import org.tailormap.api.persistence.json.AppLayerSettings;
  import org.tailormap.api.persistence.json.AppTreeLayerNode;
  import org.tailormap.api.persistence.json.AttributeSettings;
  import org.tailormap.api.persistence.json.FeatureTypeTemplate;
  import org.tailormap.api.persistence.json.GeoServiceLayer;
  import org.tailormap.api.persistence.json.TMAttributeDescriptor;
  import org.tailormap.api.persistence.json.TMAttributeType;
  import org.tailormap.api.repository.FeatureSourceRepository;
  import org.tailormap.api.util.Constants;
  import org.tailormap.api.viewer.model.ColumnMetadata;
  import org.tailormap.api.viewer.model.Feature;
  import org.tailormap.api.viewer.model.FeaturesResponse;
  
  @AppRestController
  @Validated
  @RequestMapping(
      path = "${tailormap-api.base-path}/{viewerKind}/{viewerName}/layer/{appLayerId}/features",
      produces = MediaType.APPLICATION_JSON_VALUE)
  public class FeaturesController implements Constants {
    private static final Logger logger =
        LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
  
    private final FeatureSourceFactoryHelper featureSourceFactoryHelper;
  
    private final FeatureSourceRepository featureSourceRepository;
    private final FilterFactory ff = CommonFactoryFinder.getFilterFactory(GeoTools.getDefaultHints());
  
    @Value("${tailormap-api.pageSize:100}")
    private int pageSize;
  
    @Value("${tailormap-api.feature.info.maxitems:30}")
    private int maxFeatures;
  
    @Value("${tailormap-api.features.wfs_count_exact:false}")
    private boolean exactWfsCounts;
  
    public FeaturesController(
        FeatureSourceFactoryHelper featureSourceFactoryHelper,
        FeatureSourceRepository featureSourceRepository) {
      this.featureSourceFactoryHelper = featureSourceFactoryHelper;
     this.featureSourceRepository = featureSourceRepository;
   }
 
   @Transactional
   @RequestMapping(method = {GET, POST})
   @Timed(value = "get_features", description = "time spent to process get features call")
   public ResponseEntity<Serializable> getFeatures(
       @ModelAttribute AppTreeLayerNode appTreeLayerNode,
       @ModelAttribute GeoService service,
       @ModelAttribute GeoServiceLayer layer,
       @ModelAttribute Application application,
       @RequestParam(required = false) Double x,
       @RequestParam(required = false) Double y,
       @RequestParam(defaultValue = "4") Double distance,
       @RequestParam(required = false) String __fid,
       @RequestParam(defaultValue = "false") Boolean simplify,
       @RequestParam(required = false) String filter,
       @RequestParam(required = false) Integer page,
       @RequestParam(required = false) String sortBy,
       @RequestParam(required = false, defaultValue = "asc") String sortOrder,
       @RequestParam(defaultValue = "false") boolean onlyGeometries,
       @RequestParam(defaultValue = "false") boolean geometryInAttributes) {
 
     if (layer == null) {
       throw new ResponseStatusException(
           HttpStatus.NOT_FOUND, "Can't find layer " + appTreeLayerNode);
     }
 
     TMFeatureType tmft = service.findFeatureTypeForLayer(layer, featureSourceRepository);
     if (tmft == null) {
       throw new ResponseStatusException(HttpStatus.NOT_FOUND, "Layer does not have feature type");
     }
     AppLayerSettings appLayerSettings = application.getAppLayerSettings(appTreeLayerNode);
 
     if (onlyGeometries) {
       geometryInAttributes = true;
     }
 
     FeaturesResponse featuresResponse;
 
     if (null != __fid) {
       featuresResponse =
           getFeatureByFID(tmft, appLayerSettings, __fid, application, !geometryInAttributes);
     } else if (null != x && null != y) {
       featuresResponse =
           getFeaturesByXY(
               tmft,
               appLayerSettings,
               filter,
               x,
               y,
               application,
               distance,
               simplify,
               !geometryInAttributes);
     } else if (null != page && page > 0) {
       featuresResponse =
           getAllFeatures(
               tmft,
               application,
               appLayerSettings,
               page,
               filter,
               sortBy,
               sortOrder,
               onlyGeometries,
               !geometryInAttributes);
     } else {
       throw new ResponseStatusException(
           HttpStatus.BAD_REQUEST, "Unsupported combination of request parameters");
     }
 
     return ResponseEntity.status(HttpStatus.OK).body(featuresResponse);
   }
 
   @NotNull
   private FeaturesResponse getAllFeatures(
       @NotNull TMFeatureType tmft,
       @NotNull Application application,
       @NotNull AppLayerSettings appLayerSettings,
       Integer page,
       String filterCQL,
       String sortBy,
       String sortOrder,
       boolean onlyGeometries,
       boolean skipGeometryOutput) {
     FeaturesResponse featuresResponse = new FeaturesResponse().page(page).pageSize(pageSize);
 
     SimpleFeatureSource fs = null;
     try {
       fs = featureSourceFactoryHelper.openGeoToolsFeatureSource(tmft);
 
       // TODO evaluate; do we want geometry in this response or not?
       //  if we do the geometry attribute must not be removed from propNames
 
       // Property names for query: only non-geometry attributes that aren't hidden
       List<String> propNames =
           getConfiguredAttributes(tmft, appLayerSettings).values().stream()
               .map(Pair::getLeft)
               .filter(a -> !isGeometry(a.getType()))
               .map(TMAttributeDescriptor::getName)
               .collect(Collectors.toList());
 
       String sortAttrName;
       if (onlyGeometries) {
         propNames = List.of(tmft.getDefaultGeometryAttribute());
         // do not try to sort by geometry
         sortAttrName = null;
       } else {
         if (propNames.isEmpty()) {
           return featuresResponse;
         }
         // Default sorting attribute if sortBy not specified or not a configured attribute
         if (tmft.getPrimaryKeyAttribute() != null
             && propNames.contains(tmft.getPrimaryKeyAttribute())) {
           // There is a primary key and it is known, use that for sorting
           sortAttrName = tmft.getPrimaryKeyAttribute();
         } else {
           sortAttrName = propNames.get(0);
         }
 
         if (null != sortBy) {
           // Only use sortBy attribute if it is in the list of configured attributes and not a
           // geometry type (propNames does not contain geometry attributes, see above)
           if (propNames.contains(sortBy)) {
             sortAttrName = sortBy;
           } else {
             logger.warn(
                 "Requested sortBy attribute {} was not found in configured attributes or is a geometry attribute",
                 sortBy);
           }
         }
       }
 
       SortOrder _sortOrder = SortOrder.ASCENDING;
       if (null != sortOrder
           && (sortOrder.equalsIgnoreCase("desc") || sortOrder.equalsIgnoreCase("asc"))) {
         _sortOrder = SortOrder.valueOf(sortOrder.toUpperCase(Locale.ROOT));
       }
 
       // setup query, attributes and filter
       Query q = new Query(fs.getName().toString());
       q.setPropertyNames(propNames);
 
       // count can be -1 if too costly eg. some WFS
       int featureCount;
       if (null != filterCQL) {
         Filter filter = ECQL.toFilter(filterCQL);
         q.setFilter(filter);
         featureCount = fs.getCount(q);
         // this will execute the query twice, once to get the count and once to get the data
         if (featureCount == -1 && exactWfsCounts) {
           featureCount = fs.getFeatures(q).size();
         }
       } else {
         featureCount = fs.getCount(Query.ALL);
         // this will execute the query twice, once to get the count and once to get the data
         if (featureCount == -1 && exactWfsCounts) {
           featureCount = fs.getFeatures(Query.ALL).size();
         }
       }
       featuresResponse.setTotal(featureCount);
 
       // setup page query
       if (sortAttrName != null) {
         q.setSortBy(ff.sort(sortAttrName, _sortOrder));
       }
       q.setMaxFeatures(pageSize);
       q.setStartIndex((page - 1) * pageSize);
       logger.debug("Attribute query: {}", q);
 
       executeQueryOnFeatureSourceAndClose(
           false,
           featuresResponse,
           tmft,
           appLayerSettings,
           onlyGeometries,
           fs,
           q,
           application,
           skipGeometryOutput);
     } catch (IOException e) {
       logger.error("Could not retrieve attribute data.", e);
     } catch (CQLException e) {
       logger.error("Could not parse requested filter.", e);
       throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Could not parse requested filter");
     } finally {
       if (fs != null) {
         fs.getDataStore().dispose();
       }
     }
 
     return featuresResponse;
   }
 
   @NotNull
   private FeaturesResponse getFeatureByFID(
       @NotNull TMFeatureType tmFeatureType,
       @NotNull AppLayerSettings appLayerSettings,
       @NotNull String fid,
       @NotNull Application application,
       boolean skipGeometryOutput) {
     FeaturesResponse featuresResponse = new FeaturesResponse();
 
     SimpleFeatureSource fs = null;
     try {
       fs = featureSourceFactoryHelper.openGeoToolsFeatureSource(tmFeatureType);
       Query q = new Query(fs.getName().toString());
       q.setFilter(ff.id(ff.featureId(fid)));
       q.setMaxFeatures(1);
       logger.debug("FID query: {}", q);
 
       executeQueryOnFeatureSourceAndClose(
           false,
           featuresResponse,
           tmFeatureType,
           appLayerSettings,
           false,
           fs,
           q,
           application,
           skipGeometryOutput);
     } catch (IOException e) {
       logger.error("Could not retrieve attribute data", e);
     } finally {
       if (fs != null) {
         fs.getDataStore().dispose();
       }
     }
 
     return featuresResponse;
   }
 
   @NotNull
   private FeaturesResponse getFeaturesByXY(
       @NotNull TMFeatureType tmFeatureType,
       @NotNull AppLayerSettings appLayerSettings,
       String filterCQL,
       @NotNull Double x,
       @NotNull Double y,
       @NotNull Application application,
       @NotNull Double distance,
       @NotNull Boolean simplifyGeometry,
       boolean skipGeometryOutput) {
 
     if (null != distance && 0d >= distance) {
       throw new ResponseStatusException(
           HttpStatus.BAD_REQUEST, "Buffer distance must be greater than 0");
     }
 
     FeaturesResponse featuresResponse = new FeaturesResponse();
 
     SimpleFeatureSource fs;
     try {
       GeometricShapeFactory shapeFact = new GeometricShapeFactory();
       shapeFact.setNumPoints(32);
       shapeFact.setCentre(new Coordinate(x, y));
       //noinspection ConstantConditions
       shapeFact.setSize(distance * 2d);
       Geometry p = shapeFact.createCircle();
       logger.debug("created geometry: {}", p);
 
       MathTransform transform = null;
       fs = featureSourceFactoryHelper.openGeoToolsFeatureSource(tmFeatureType);
       try {
         transform = TransformationUtil.getTransformationToDataSource(application, fs);
       } catch (FactoryException e) {
         logger.warn("Unable to find transformation from query geometry to desired datasource", e);
       }
       if (null != transform) {
         try {
           p = JTS.transform(p, transform);
           logger.debug("reprojected geometry to: {}", p);
         } catch (TransformException e) {
           logger.warn(
               "Unable to transform query geometry to desired CRS, trying with original CRS");
         }
       }
       logger.debug("using selection geometry: {}", p);
       Filter spatialFilter =
           ff.intersects(ff.property(tmFeatureType.getDefaultGeometryAttribute()), ff.literal(p));
 
       Filter finalFilter = spatialFilter;
       if (null != filterCQL) {
         Filter filter = ECQL.toFilter(filterCQL);
         finalFilter = ff.and(spatialFilter, filter);
       }
       Query q = new Query(fs.getName().toString());
       q.setFilter(finalFilter);
       q.setMaxFeatures(maxFeatures);
 
       executeQueryOnFeatureSourceAndClose(
           simplifyGeometry,
           featuresResponse,
           tmFeatureType,
           appLayerSettings,
           false,
           fs,
           q,
           application,
           skipGeometryOutput);
     } catch (IOException e) {
       logger.error("Could not retrieve attribute data", e);
     } catch (CQLException e) {
       logger.error("Could not parse requested filter.", e);
       throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Could not parse requested filter");
     }
     return featuresResponse;
   }
 
   private void executeQueryOnFeatureSourceAndClose(
       boolean simplifyGeometry,
       @NotNull FeaturesResponse featuresResponse,
       @NotNull TMFeatureType tmFeatureType,
       @NotNull AppLayerSettings appLayerSettings,
       boolean onlyGeometries,
       @NotNull SimpleFeatureSource featureSource,
       @NotNull Query selectQuery,
       @NotNull Application application,
       boolean skipGeometryOutput)
       throws IOException {
     boolean addFields = false;
 
     MathTransform transform = null;
     try {
       transform = TransformationUtil.getTransformationToApplication(application, featureSource);
     } catch (FactoryException e) {
       logger.error("Can not transform geometry to desired CRS", e);
     }
 
     Map<String, Pair<TMAttributeDescriptor, AttributeSettings>> configuredAttributes =
         getConfiguredAttributes(tmFeatureType, appLayerSettings);
 
     // send request to attribute source
     try (SimpleFeatureIterator feats = featureSource.getFeatures(selectQuery).features()) {
       while (feats.hasNext()) {
         addFields = true;
         // transform found simplefeatures to list of Feature
         SimpleFeature feature = feats.next();
         // processedGeometry can be null
         String processedGeometry =
             GeometryProcessor.processGeometry(
                 feature.getAttribute(tmFeatureType.getDefaultGeometryAttribute()),
                 simplifyGeometry,
                 true,
                 transform);
         Feature newFeat =
             new Feature().fid(feature.getIdentifier().getID()).geometry(processedGeometry);
 
         if (!onlyGeometries) {
           for (String attName : configuredAttributes.keySet()) {
             Object value = feature.getAttribute(attName);
             if (value instanceof Geometry) {
               if (skipGeometryOutput) {
                 value = null;
               } else {
                 value = GeometryProcessor.geometryToWKT((Geometry) value);
               }
             }
             newFeat.putAttributesItem(attName, value);
           }
         }
         featuresResponse.addFeaturesItem(newFeat);
       }
     } finally {
       featureSource.getDataStore().dispose();
     }
     FeatureTypeTemplate ftt = tmFeatureType.getSettings().getTemplate();
     if (ftt != null) {
       featuresResponse.setTemplate(ftt.getTemplate());
     }
     if (addFields) {
       configuredAttributes.values().stream()
           .map(
               pair -> {
                 TMAttributeDescriptor attributeDescriptor = pair.getLeft();
                 TMAttributeType type = attributeDescriptor.getType();
                 AttributeSettings settings = pair.getRight();
                 return new ColumnMetadata()
                     .key(attributeDescriptor.getName())
                     .alias(settings.getTitle())
                     .type(isGeometry(type) ? TMAttributeType.GEOMETRY : type);
               })
           .forEach(featuresResponse::addColumnMetadataItem);
     }
   }
 }