/**
 * 
 */
package org.gcube.accounting.analytics.persistence.couchbase;

import static com.couchbase.client.java.query.Select.select;
import static com.couchbase.client.java.query.dsl.Expression.s;
import static com.couchbase.client.java.query.dsl.Expression.x;

import java.util.Calendar;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.gcube.accounting.analytics.Filter;
import org.gcube.accounting.analytics.Info;
import org.gcube.accounting.analytics.TemporalConstraint;
import org.gcube.accounting.analytics.TemporalConstraint.AggregationMode;
import org.gcube.accounting.analytics.persistence.AccountingPersistenceBackendQuery;
import org.gcube.accounting.analytics.persistence.AccountingPersistenceBackendQueryConfiguration;
import org.gcube.accounting.datamodel.BasicUsageRecord;
import org.gcube.accounting.datamodel.UsageRecord;
import org.gcube.accounting.persistence.AccountingPersistence;
import org.gcube.accounting.persistence.AccountingPersistenceConfiguration;
import org.gcube.common.scope.api.ScopeProvider;
import org.gcube.documentstore.records.AggregatedRecord;
import org.gcube.documentstore.records.Record;
import org.gcube.documentstore.records.RecordUtility;
import org.json.JSONException;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.couchbase.client.java.Bucket;
import com.couchbase.client.java.Cluster;
import com.couchbase.client.java.CouchbaseCluster;
import com.couchbase.client.java.document.json.JsonObject;
import com.couchbase.client.java.env.CouchbaseEnvironment;
import com.couchbase.client.java.env.DefaultCouchbaseEnvironment;
import com.couchbase.client.java.query.N1qlQueryResult;
import com.couchbase.client.java.query.N1qlQueryRow;
import com.couchbase.client.java.query.dsl.Expression;
import com.couchbase.client.java.query.dsl.path.GroupByPath;

/**
 * @author Luca Frosini (ISTI - CNR) http://www.lucafrosini.com/
 *
 */
public class AccountingPersistenceQueryCouchBase extends AccountingPersistenceBackendQuery {

	private static final Logger logger = LoggerFactory.getLogger(AccountingPersistenceQueryCouchBase.class);
	
	public static final String URL_PROPERTY_KEY = AccountingPersistenceConfiguration.URL_PROPERTY_KEY;
	//public static final String USERNAME_PROPERTY_KEY = AccountingPersistenceConfiguration.USERNAME_PROPERTY_KEY;
	public static final String PASSWORD_PROPERTY_KEY = AccountingPersistenceConfiguration.PASSWORD_PROPERTY_KEY;
	public static final String BUCKET_NAME_PROPERTY_KEY = "bucketName";
	
	/* The environment configuration */
    protected static final CouchbaseEnvironment ENV = 
    	DefaultCouchbaseEnvironment.builder()
    	.queryEnabled(true)
    	.build();
	
	protected Cluster cluster;
	protected Bucket bucket;
	protected String bucketName;

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected void prepareConnection(AccountingPersistenceBackendQueryConfiguration configuration) throws Exception {
		String url = configuration.getProperty(URL_PROPERTY_KEY);
		// String username = configuration.getProperty(USERNAME_PROPERTY_KEY);
		String password = configuration.getProperty(PASSWORD_PROPERTY_KEY);

		cluster = CouchbaseCluster.create(ENV, url);
		bucketName = configuration.getProperty(BUCKET_NAME_PROPERTY_KEY);
		bucket = cluster.openBucket(bucketName, password);
	}
		
	/**
	 * {@inheritDoc}
	 */
	@Override
	public void close() throws Exception {
		cluster.disconnect();
	}

	protected Calendar getCalendar(JSONObject obj, AggregationMode aggregationMode) throws NumberFormatException, JSONException{
		long millis;
		if(obj.has(AggregatedRecord.START_TIME)){
			millis = new Long(obj.getString(AggregatedRecord.START_TIME));
			logger.trace("The result {} was from an aggregated record. Using {}", obj.toString(), AggregatedRecord.START_TIME);
		}else{
			millis = new Long(obj.getString(UsageRecord.CREATION_TIME));
			logger.trace("The result {} was from single record. Using {}", obj.toString(), UsageRecord.CREATION_TIME);
		}
		Calendar calendar = TemporalConstraint.getAlignedCalendar(millis, aggregationMode);
		logger.trace("{} has been aligned to {}", millis, calendar.getTimeInMillis());
		return calendar;
	}
	
	/**
	 * {@inheritDoc}
	 */
	@Override
	protected Map<Calendar, Info> reallyQuery(
			@SuppressWarnings("rawtypes") Class<? extends AggregatedRecord> recordClass,
			TemporalConstraint temporalConstraint, List<Filter> filters)
			throws Exception {
		
		//String currentScope = BasicUsageRecord.getScopeFromToken();
		String currentScope = ScopeProvider.instance.get();
		String recordType = recordClass.newInstance().getRecordType();
		
		Expression expression = x(BasicUsageRecord.SCOPE).eq(s(currentScope));
		expression = expression.and(x(BasicUsageRecord.RECORD_TYPE).eq(s(recordType)));
		
		long startTime = temporalConstraint.getAlignedStartTime().getTimeInMillis();
		expression = expression.and(
				x(AggregatedRecord.START_TIME).gt(startTime).
				or(x(AggregatedRecord.CREATION_TIME).gt(startTime)));
		
		long endTime = temporalConstraint.getAlignedEndTime().getTimeInMillis();
		expression = expression.and(
				x(AggregatedRecord.END_TIME).lt(endTime)).
				or(x(AggregatedRecord.CREATION_TIME).lt(endTime));
		
		AggregationMode aggregationMode =  temporalConstraint.getAggregationMode();
		
		if(filters!=null){
			for(Filter filter : filters){
				expression = expression.and(x(filter.getKey()).eq(s(filter.getValue())));
			}
		}
		
		GroupByPath groupByPath = select("*").from(bucketName).where(expression);

		N1qlQueryResult result = bucket.query(groupByPath);
		List<N1qlQueryRow> rows = result.allRows();
		Map<Calendar, Info> map = new HashMap<Calendar, Info>();
		
		for(N1qlQueryRow row : rows){
			logger.debug(row.toString());
			JsonObject jsonObject = row.value().getObject(bucketName);
			Record record = RecordUtility.getRecord(jsonObject.toMap().toString());
			
			JSONObject obj = new JSONObject(jsonObject.toString());
			Calendar calendar = getCalendar(obj, aggregationMode);
			if(map.containsKey(calendar)){
				Info info = map.get(calendar);
				JSONObject value = info.getValue();
				jsonObject.toMap();
				
			}else{
				map.put(calendar, new Info(calendar, obj));
			}
		}

		return map;
	}


	/**
	 * {@inheritDoc}
	 */
	@Override
	public Set<String> getKeys(Class<? extends AggregatedRecord> recordClass)
			throws Exception {
		// TODO Auto-generated method stub
		return null;
	}


	/**
	 * {@inheritDoc}
	 */
	@Override
	public Set<String> getPossibleValuesForKey(
			Class<? extends AggregatedRecord> recordClass, String key)
			throws Exception {
		// TODO Auto-generated method stub
		// SELECT DISTINCT
		return null;
	}

	/* (non-Javadoc)
	 * @see org.gcube.accounting.analytics.persistence.AccountingPersistenceBackendQuery#getPossibleValuesForKey(java.lang.Class, java.lang.String, int)
	 */
	@Override
	public Set<String> getPossibleValuesForKey(
			Class<? extends AggregatedRecord> recordClass, String key, int limit)
			throws Exception {
		// TODO Auto-generated method stub
		return null;
	}

	
}