uoa-repository-manager-service/src/main/java/eu/dnetlib/repo/manager/service/controllers/StatsApiImpl.java

package eu.dnetlib.repo.manager.service.controllers;

import com.mongodb.util.JSON;
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.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.stereotype.Component;
import org.springframework.web.client.RestTemplate;
import org.springframework.web.util.UriComponents;
import org.springframework.web.util.UriComponentsBuilder;

import javax.annotation.PostConstruct;
import java.util.HashMap;
import java.util.Map;

@Component
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 = getTotalByType("datasource",baseAddress+"/resources",
                "?query= " +
                " oaftype exact datasource and " +
                " ( datasourcetypename exact Institutional Repository Aggregator " +
                "     or datasourcetypename exact Publication Repository Aggregator )");

        String dataRepositories = getTotalByType("datasource",baseAddress+"/resources",
                "?query= " +
                " oaftype exact datasource and " +
                " datasourcetypename exact Data Repository " );

        String literature = getTotalByType("datasource",baseAddress+"/resources",
                "?query= " +
                " oaftype exact datasource and " +
                " ( datasourcetypename exact Institutional Repository  " +
                "     or datasourcetypename exact Publication Repository )");

        String journal = getTotalByType("datasource",baseAddress+"/resources",
                "?query= " +
                " oaftype exact datasource and " +
                " datasourcetypename exact Journal");

        String publications = getTotalByType("other",baseAddress,"/publications/count");
        String datasets = getTotalByType("other",baseAddress,"/datasets/count");
        String software = getTotalByType("other",baseAddress,"/software/count");
        JSONObject lastYearUsagestats = getLastYearUsageStatsTotal();
        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.toString());
        stats.put("usagestats",usagestats.toString());


        return stats;
    }


    private String getTotalByType(String type,String url,String query) throws JSONException {
        UriComponents uriComponents = UriComponentsBuilder
                .fromHttpUrl(url + query)
                .queryParam("page",0)
                .queryParam("size",0)
                .queryParam("format","json")
                .build().encode();

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

        if(type.equalsIgnoreCase("datasource")){
            JSONObject metadata = (JSONObject) new JSONObject(rs).get("meta");
            return String.valueOf(metadata.get("total"));
        }else
            return String.valueOf(new JSONObject(rs).get("total"));

    }

    private JSONObject getLastYearUsageStatsTotal() throws JSONException {

        UriComponents uriComponents = UriComponentsBuilder
                .fromHttpUrl(usagestatsBaseAddress + "/totals")
                .build().encode();

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

        JSONArray resultSet = (JSONArray) new JSONObject(rs).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;

    }

    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"));
    }
}