/*
    * Copyright 2015 Data Archiving and Networked Services (an institute of
    * Koninklijke Nederlandse Akademie van Wetenschappen), King's College London,
    * Georg-August-Universitaet Goettingen Stiftung Oeffentlichen Rechts
    *
    * Licensed under the EUPL, Version 1.1 or – as soon they will be approved by
    * the European Commission - subsequent versions of the EUPL (the "Licence");
    * You may not use this work except in compliance with the Licence.
    * You may obtain a copy of the Licence at:
   *
   * https://joinup.ec.europa.eu/software/page/eupl
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the Licence is distributed on an "AS IS" basis,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the Licence for the specific language governing
   * permissions and limitations under the Licence.
   */
  
  package eu.ehri.extension.providers;
  
  import com.fasterxml.jackson.core.JsonParseException;
  import com.fasterxml.jackson.core.type.TypeReference;
  import com.fasterxml.jackson.databind.JsonMappingException;
  import com.fasterxml.jackson.databind.ObjectReader;
  import com.fasterxml.jackson.databind.ObjectWriter;
  import com.fasterxml.jackson.dataformat.csv.CsvGenerator;
  import com.fasterxml.jackson.dataformat.csv.CsvMapper;
  import com.fasterxml.jackson.dataformat.csv.CsvParser;
  import com.fasterxml.jackson.dataformat.csv.CsvSchema;
  import eu.ehri.extension.base.AbstractResource;
  import eu.ehri.extension.errors.WebDeserializationError;
  import eu.ehri.project.utils.Table;
  import eu.ehri.project.exceptions.DeserializationError;
  
  import javax.ws.rs.Consumes;
  import javax.ws.rs.Produces;
  import javax.ws.rs.WebApplicationException;
  import javax.ws.rs.core.MediaType;
  import javax.ws.rs.core.MultivaluedMap;
  import javax.ws.rs.ext.MessageBodyReader;
  import javax.ws.rs.ext.MessageBodyWriter;
  import javax.ws.rs.ext.Provider;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.lang.annotation.Annotation;
  import java.lang.reflect.Type;
  import java.util.List;
  
  /**
   * Provider for row/column data.
   * <p>
   * TODO: Handle CSV headers
   */
  @Provider
  @Produces({MediaType.APPLICATION_JSON, AbstractResource.CSV_MEDIA_TYPE})
  @Consumes({MediaType.APPLICATION_JSON, AbstractResource.CSV_MEDIA_TYPE})
  public class TableProvider implements MessageBodyWriter<Table>, MessageBodyReader<Table>, JsonMessageBodyHandler {
  
      private static CsvMapper csvMapper = new CsvMapper()
              .enable(CsvGenerator.Feature.STRICT_CHECK_FOR_QUOTING)
              .enable(CsvParser.Feature.WRAP_AS_ARRAY);
      private static CsvSchema csvSchema = csvMapper.schemaFor(List.class);
  
      private static TypeReference<List<List<String>>> typeRef = new TypeReference<List<List<String>>>() {
      };
  
      @Override
      public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
          return Table.class.equals(type);
      }
  
      @Override
      public long getSize(Table table, Class<?> aClass, Type type, Annotation[] annotations,
              MediaType mediaType) {
          return -1L;
      }
  
      @Override
      public void writeTo(Table table,
              Class<?> aClass, Type type, Annotation[] annotations,
              MediaType mediaType, MultivaluedMap<String, Object> headers,
              OutputStream outputStream) throws IOException, WebApplicationException {
          ObjectWriter writer = mediaType.isCompatible(MediaType.APPLICATION_JSON_TYPE)
                  ? mapper.writer()
                  : csvMapper.writer(csvSchema.withoutHeader());
          writer.writeValue(outputStream, table.rows());
      }
  
      @Override
      public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
          return Table.class.equals(type);
      }
  
      @Override
      public Table readFrom(Class<Table> type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String, String> httpHeaders, InputStream entityStream) throws IOException, WebApplicationException {
          try {
              ObjectReader reader = mediaType.isCompatible(MediaType.APPLICATION_JSON_TYPE)
                     ? mapper.readerFor(typeRef)
                     : csvMapper.readerFor(typeRef).with(csvSchema.withoutHeader());
             return Table.of(reader.readValue(entityStream));
         } catch (JsonMappingException | JsonParseException e) {
             throw new WebDeserializationError(new DeserializationError(
                     "Deserialization error for media type: " + mediaType, e));
         }
     }
 }