/*
    * Copyright (C) 2022 B3Partners B.V.
    *
    * SPDX-License-Identifier: MIT
    */
   package org.tailormap.api.geotools.featuresources;
   
   import static org.geotools.jdbc.JDBCDataStore.JDBC_PRIMARY_KEY_COLUMN;
   import static org.geotools.jdbc.JDBCDataStore.JDBC_READ_ONLY;
  import static org.tailormap.api.persistence.helper.GeoToolsHelper.crsToString;
  
  import java.io.IOException;
  import java.lang.invoke.MethodHandles;
  import java.util.Arrays;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import org.apache.commons.lang3.StringUtils;
  import org.geotools.api.data.DataStore;
  import org.geotools.api.data.DataStoreFinder;
  import org.geotools.api.data.ResourceInfo;
  import org.geotools.api.data.ServiceInfo;
  import org.geotools.api.data.SimpleFeatureSource;
  import org.geotools.api.feature.simple.SimpleFeatureType;
  import org.geotools.api.feature.type.AttributeDescriptor;
  import org.geotools.api.feature.type.AttributeType;
  import org.geotools.jdbc.JDBCFeatureStore;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.tailormap.api.persistence.TMFeatureSource;
  import org.tailormap.api.persistence.TMFeatureType;
  import org.tailormap.api.persistence.helper.GeoToolsHelper;
  import org.tailormap.api.persistence.json.TMAttributeDescriptor;
  import org.tailormap.api.persistence.json.TMAttributeType;
  import org.tailormap.api.persistence.json.TMFeatureTypeInfo;
  import org.tailormap.api.persistence.json.TMServiceCaps;
  import org.tailormap.api.persistence.json.TMServiceInfo;
  
  public abstract class FeatureSourceHelper {
    private static final Logger logger =
        LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
  
    public DataStore createDataStore(TMFeatureSource tmfs) throws IOException {
      return createDataStore(tmfs, null);
    }
  
    /**
     * Create a GeoTools DataStore for the given TMFeatureSource.
     *
     * @param tmfs The feature source for which to create the datastore
     * @param timeout Optional timeout in milliseconds for datastore operations, if supported by the datastore
     *     implementation
     * @return The created DataStore
     * @throws IOException If an error occurs while creating the DataStore
     */
    public abstract DataStore createDataStore(TMFeatureSource tmfs, Integer timeout) throws IOException;
  
    public SimpleFeatureSource openGeoToolsFeatureSource(TMFeatureType tmft, Integer timeout) throws IOException {
      DataStore ds = createDataStore(tmft.getFeatureSource(), timeout);
      return ds.getFeatureSource(tmft.getName());
    }
  
    public void loadCapabilities(TMFeatureSource tmfs) throws IOException {
      loadCapabilities(tmfs, null);
    }
  
    public DataStore openDatastore(Map<String, Object> params, String passwordKey) throws IOException {
      Map<String, Object> logParams = new HashMap<>(params);
      String passwd = (String) params.get(passwordKey);
      if (passwd != null) {
        logParams.put(passwordKey, String.valueOf(new char[passwd.length()]).replace("\0", "*"));
      }
      logger.debug("Opening datastore using parameters: {}", logParams);
      DataStore ds;
      try {
        ds = DataStoreFinder.getDataStore(params);
      } catch (Exception e) {
        throw new IOException("Cannot open datastore using parameters: " + logParams, e);
      }
      if (ds == null) {
        throw new IOException("No datastore found using parameters " + logParams);
      }
      return ds;
    }
  
    public void loadCapabilities(TMFeatureSource tmfs, Integer timeout) throws IOException {
      DataStore ds = createDataStore(tmfs, timeout);
      try {
        if (StringUtils.isBlank(tmfs.getTitle())) {
          tmfs.setTitle(ds.getInfo().getTitle());
        }
  
        ServiceInfo si = ds.getInfo();
        tmfs.setServiceCapabilities(new TMServiceCaps()
            .serviceInfo(new TMServiceInfo()
                .title(si.getTitle())
                .keywords(si.getKeywords())
                .description(si.getDescription())
                .publisher(si.getPublisher())
               .schema(si.getSchema())
               .source(si.getSource())));
 
       List<String> typeNames = Arrays.asList(ds.getTypeNames());
       logger.debug(
           "Type names for {} {}: {}",
           tmfs.getProtocol().getValue(),
           tmfs.getProtocol() == TMFeatureSource.Protocol.WFS ? tmfs.getUrl() : tmfs.getJdbcConnection(),
           typeNames);
 
       tmfs.getFeatureTypes().removeIf(tmft -> {
         if (!typeNames.contains(tmft.getName())) {
           logger.debug("Feature type removed: {}", tmft.getName());
           return true;
         } else {
           return false;
         }
       });
 
       for (String typeName : typeNames) {
         TMFeatureType pft = tmfs.getFeatureTypes().stream()
             .filter(ft -> ft.getName().equals(typeName))
             .findFirst()
             .orElseGet(() -> new TMFeatureType().setName(typeName).setFeatureSource(tmfs));
         if (!tmfs.getFeatureTypes().contains(pft)) {
           tmfs.getFeatureTypes().add(pft);
         }
         try {
           logger.debug("Get feature source from GeoTools datastore for type \"{}\"", typeName);
           SimpleFeatureSource gtFs = ds.getFeatureSource(typeName);
           ResourceInfo info = gtFs.getInfo();
           if (info != null) {
             pft.setTitle(info.getTitle());
             pft.setInfo(getFeatureTypeInfo(pft, info, gtFs));
             pft.getAttributes().clear();
 
             SimpleFeatureType gtFt = gtFs.getSchema();
             pft.setWriteable(gtFs instanceof JDBCFeatureStore
                 && !Boolean.TRUE.equals(gtFt.getUserData().get(JDBC_READ_ONLY)));
             String primaryKeyName = null;
             for (AttributeDescriptor gtAttr : gtFt.getAttributeDescriptors()) {
               AttributeType type = gtAttr.getType();
               if (Boolean.TRUE.equals(gtAttr.getUserData().get(JDBC_PRIMARY_KEY_COLUMN))) {
                 if (primaryKeyName == null) {
                   logger.debug(
                       "Found primary key attribute \"{}\" for type \"{}\"",
                       gtAttr.getLocalName(),
                       typeName);
                   primaryKeyName = gtAttr.getLocalName();
                 } else {
                   logger.warn(
                       "Multiple primary key attributes found for type \"{}\": \"{}\" and \"{}\". Composite primary keys are not supported for writing, setting as read-only.",
                       typeName,
                       primaryKeyName,
                       gtAttr.getLocalName());
                   pft.setWriteable(false);
                 }
               }
               TMAttributeDescriptor tmAttr = new TMAttributeDescriptor()
                   .name(gtAttr.getLocalName())
                   .type(GeoToolsHelper.toAttributeType(type))
                   .nullable(gtAttr.isNillable())
                   .defaultValue(
                       gtAttr.getDefaultValue() == null
                           ? null
                           : gtAttr.getDefaultValue().toString())
                   .description(
                       type.getDescription() == null
                           ? null
                           : type.getDescription().toString());
               if (tmAttr.getType() == TMAttributeType.OBJECT) {
                 tmAttr.setUnknownTypeClassName(type.getBinding().getName());
               }
               pft.getAttributes().add(tmAttr);
             }
             pft.setPrimaryKeyAttribute(primaryKeyName);
             pft.setDefaultGeometryAttribute(pft.findDefaultGeometryAttribute());
           }
         } catch (Exception e) {
           logger.error("Exception reading feature type \"{}\"", typeName, e);
         }
       }
     } finally {
       ds.dispose();
     }
   }
 
   protected TMFeatureTypeInfo getFeatureTypeInfo(TMFeatureType pft, ResourceInfo info, SimpleFeatureSource gtFs) {
     return new TMFeatureTypeInfo()
         .keywords(info.getKeywords())
         .description(info.getDescription())
         .bounds(GeoToolsHelper.fromEnvelope(info.getBounds()))
         .crs(crsToString(info.getCRS()));
   }
 }