D-Net

package eu.dnetlib.repo.manager.service;

import eu.dnetlib.repo.manager.exception.EndPointException;

import org.apache.log4j.Logger;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;

import org.springframework.beans.factory.annotation.Value;

import org.springframework.http.HttpHeaders;

import org.springframework.http.HttpStatus;

import org.springframework.http.ResponseEntity;

import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;

import org.springframework.stereotype.Component;

import org.springframework.stereotype.Service;

import org.springframework.web.client.RestTemplate;

import org.springframework.web.util.UriComponents;

import org.springframework.web.util.UriComponentsBuilder;

import javax.annotation.PostConstruct;

import java.rmi.ServerError;

import java.util.HashMap;

import java.util.Map;

@Service("statsService")

public class StatsApiImpl implements StatsApi {

    private RestTemplate restTemplate = null;

    private HttpHeaders httpHeaders;

    private static final Logger LOGGER = Logger.getLogger(RepositoryApiImpl.class);

    @Value("${search.api.baseAddress}")

    private String baseAddress;

    @Value("${search.api.usagestats}")

    private String usagestatsBaseAddress;

    @Value("${search.api.usageEvents}")

    private String usagestatsEvents;

    @PostConstruct

    private void init() {

        LOGGER.debug("Initialization method of statistics api!");

        restTemplate = new RestTemplate();

        restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

        httpHeaders = new HttpHeaders();

        httpHeaders.set("Content-Type", "application/json");

    }

    @Override

    public Map<String, Object> getStatistics() throws JSONException {

        String aggregators = null;

        try {

            aggregators = getTotalByType("datasource",baseAddress+"/resources",

                    "?query= " +

                    " oaftype exact datasource and " +

                    " ( datasourcetypename exact Institutional Repository Aggregator " +

                    "     or datasourcetypename exact Publication Repository Aggregator )");

        } catch (EndPointException e) {

            LOGGER.debug(e);

            aggregators = "N/A";

        }

        String dataRepositories = null;

        try {

            dataRepositories = getTotalByType("datasource",baseAddress+"/resources",

                    "?query= " +

                    " oaftype exact datasource and " +

                    " datasourcetypename exact Data Repository " );

        } catch (EndPointException e) {

            LOGGER.debug(e);

            dataRepositories = "N/A";

        }

        String literature = null;

        try {

            literature = getTotalByType("datasource",baseAddress+"/resources",

                    "?query= " +

                    " oaftype exact datasource and " +

                    " ( datasourcetypename exact Institutional Repository  " +

                    "     or datasourcetypename exact Publication Repository )");

        } catch (EndPointException e) {

            LOGGER.debug(e);

            literature = "N/A";

        }

        String journal = null;

        try {

            journal = getTotalByType("datasource",baseAddress+"/resources",

                    "?query= " +

                    " oaftype exact datasource and " +

                    " datasourcetypename exact Journal");

        } catch (EndPointException e) {

            LOGGER.debug(e);

            journal = "N/A";

        }

        String publications = null;

        try {

            publications = getTotalByType("other",baseAddress,"/publications/count");

        } catch (EndPointException e) {

            LOGGER.debug(e);

            publications = "N/A";

        }

        String datasets = null;

        try {

            datasets = getTotalByType("other",baseAddress,"/datasets/count");

        } catch (EndPointException e) {

            LOGGER.debug(e);

            datasets = "N/A";

        }

        String software = null;

        try {

            software = getTotalByType("other",baseAddress,"/software/count");

        } catch (EndPointException e) {

            LOGGER.debug(e);

            software = "N/A";

        }

        JSONObject lastYearUsagestats = null;

        try {

            lastYearUsagestats = getLastYearUsageStatsTotal();

        } catch (EndPointException e) {

            LOGGER.debug(e);

            lastYearUsagestats = null;

        }

        Integer usagestats = getUsageStatsTotal();

        HashMap<String,Object> stats = new HashMap<>();

        stats.put("aggregators",aggregators);

        stats.put("dataRepositories",dataRepositories);

        stats.put("literature",literature);

        stats.put("journal",journal);

        stats.put("publications",publications);

        stats.put("datasets",datasets);

        stats.put("software",software);

        stats.put("lastYearUsagestats", lastYearUsagestats != null ? lastYearUsagestats.toString() : null);

        stats.put("usagestats",usagestats.toString());

        return stats;

    }

    private String getTotalByType(String type,String url,String query) throws JSONException, EndPointException {

        UriComponents uriComponents = UriComponentsBuilder

                .fromHttpUrl(url + query)

                .queryParam("page",0)

                .queryParam("size",0)

                .queryParam("format","json")

                .build().encode();

        ResponseEntity rs = restTemplate.getForObject(uriComponents.toUri(), ResponseEntity.class);

        if(rs.getStatusCode().equals(HttpStatus.OK)){

            if(type.equalsIgnoreCase("datasource")){

                JSONObject metadata = (JSONObject) new JSONObject(rs.getBody()).get("meta");

                return String.valueOf(metadata.get("total"));

            }else

                return String.valueOf(new JSONObject(rs.getBody()).get("total"));

        }else

            throw new EndPointException(uriComponents.toUri().toString());

    }

    private JSONObject getLastYearUsageStatsTotal() throws JSONException, EndPointException {

        UriComponents uriComponents = UriComponentsBuilder

                .fromHttpUrl(usagestatsBaseAddress + "/totals")

                .build().encode();

        ResponseEntity rs = restTemplate.getForObject(uriComponents.toUri(), ResponseEntity.class);

        if(rs.getStatusCode().equals(HttpStatus.OK)){

            JSONArray resultSet = (JSONArray) new JSONObject(rs.getBody()).getJSONArray("yearly_stats");

            JSONObject lastYear = resultSet.getJSONObject(resultSet.length()-1);

            Integer downloads = lastYear.getInt("downloads");

            Integer views = lastYear.getInt("views");

            String year = lastYear.getString("year");

            JSONObject usagestats = new JSONObject();

            usagestats.put("number",String.valueOf(downloads+views));

            usagestats.put("year",year);

            return usagestats;

        }else

            throw new EndPointException(uriComponents.toUri().toString());

    }

    private Integer getUsageStatsTotal() throws JSONException {

        UriComponents uriComponents = UriComponentsBuilder

                .fromHttpUrl(usagestatsEvents)

                .build().encode();

        String rs = restTemplate.getForObject(uriComponents.toUri(), String.class);

        JSONObject resultSet = new JSONObject(rs);

        JSONObject totals = resultSet.getJSONObject("totals");

        return Integer.valueOf(totals.getString("events"));

    }

}