package org.gcube.informationsystem.resourceregistry.queries.templates;

import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.gcube.com.fasterxml.jackson.databind.JavaType;
import org.gcube.com.fasterxml.jackson.databind.JsonNode;
import org.gcube.com.fasterxml.jackson.databind.ObjectMapper;
import org.gcube.common.gxhttp.reference.GXConnection;
import org.gcube.common.gxhttp.request.GXHTTPStringRequest;
import org.gcube.common.http.GXHTTPUtility;
import org.gcube.informationsystem.model.reference.ERElement;
import org.gcube.informationsystem.queries.templates.reference.entities.QueryTemplate;
import org.gcube.informationsystem.resourceregistry.api.exceptions.NotFoundException;
import org.gcube.informationsystem.resourceregistry.api.exceptions.ResourceRegistryException;
import org.gcube.informationsystem.resourceregistry.api.exceptions.queries.templates.QueryTemplateAlreadyPresentException;
import org.gcube.informationsystem.resourceregistry.api.exceptions.queries.templates.QueryTemplateNotFoundException;
import org.gcube.informationsystem.resourceregistry.api.request.BaseRequestInfo;
import org.gcube.informationsystem.resourceregistry.api.rest.AccessPath;
import org.gcube.informationsystem.resourceregistry.api.rest.QueryTemplatePath;
import org.gcube.informationsystem.resourceregistry.api.rest.httputils.HTTPUtility;
import org.gcube.informationsystem.serialization.ElementMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author Luca Frosini (ISTI - CNR)
 */
public class ResourceRegistryQueryTemplateClientImpl extends BaseRequestInfo implements ResourceRegistryQueryTemplateClient {
	
	private static final Logger logger = LoggerFactory.getLogger(ResourceRegistryQueryTemplateClientImpl.class);
	
	private static final String ACCEPT_HTTP_HEADER_KEY = "Accept";
	private static final String CONTENT_TYPE_HTTP_HEADER_KEY = "Content-Type";
	
	protected final String address;
	
	protected Map<String, String> headers;
	
	private void addOptionalQueryParameters(Map<String,String> queryParams) throws UnsupportedEncodingException {
		addIncludeMeta(queryParams);
		addIncludeAllMeta(queryParams);
	}
	
	private GXHTTPStringRequest includeAdditionalQueryParameters(GXHTTPStringRequest gxHTTPStringRequest) throws UnsupportedEncodingException{
		Map<String,String> queryParams = new HashMap<>();
		return includeAdditionalQueryParameters(gxHTTPStringRequest, queryParams);
	}
	
	private GXHTTPStringRequest includeAdditionalQueryParameters(GXHTTPStringRequest gxHTTPStringRequest, Map<String,String> queryParams) throws UnsupportedEncodingException{
		if(queryParams==null) {
			queryParams = new HashMap<>();
		}
		addOptionalQueryParameters(queryParams);
		return gxHTTPStringRequest.queryParams(queryParams);
	}
	
	private void addIncludeMeta(Map<String,String> queryParams) throws UnsupportedEncodingException{
		if(includeMeta) {
			queryParams.put(AccessPath.INCLUDE_META_QUERY_PARAMETER, Boolean.toString(includeMeta));
		}
	}
	
	private void addIncludeAllMeta(Map<String,String> queryParams) throws UnsupportedEncodingException{
		if(allMeta) {
			queryParams.put(AccessPath.INCLUDE_META_IN_ALL_INSTANCES_QUERY_PARAMETER, Boolean.toString(allMeta));
		}
	}
	
	private void addOffset(Map<String,String> queryParams) throws UnsupportedEncodingException{
		if(offset!=null) {
			queryParams.put(AccessPath.OFFSET_QUERY_PARAMETER, offset.toString());
		}
	}
	
	private void addLimit(Map<String,String> queryParams) throws UnsupportedEncodingException{
		if(limit!=null) {
			queryParams.put(AccessPath.LIMIT_QUERY_PARAMETER, limit.toString());
		}
	}
	
	@Override
	public void addHeader(String name, String value) {
		headers.put(name, value);
	}
	
	protected GXHTTPStringRequest getGXHTTPStringRequest() {
		GXHTTPStringRequest gxHTTPStringRequest = GXHTTPUtility.getGXHTTPStringRequest(address);
		gxHTTPStringRequest.from(this.getClass().getSimpleName());
		for(String name : headers.keySet()) {
			gxHTTPStringRequest.header(name, headers.get(name));
		}
		return gxHTTPStringRequest;
	}
	
	public ResourceRegistryQueryTemplateClientImpl(String address) {
		this.address = address;
		this.headers = new HashMap<>();
		this.hierarchicalMode = false;
		this.includeContexts = false;
		this.includeMeta = false;
		this.allMeta = false;
	}
	
	@Override
	public List<QueryTemplate> all() throws ResourceRegistryException {
		try {
			logger.trace("Going to list {}s", QueryTemplate.NAME);
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			
			Map<String,String> parameters = new HashMap<>();
			addIncludeMeta(parameters);
			addIncludeAllMeta(parameters);
			addOffset(parameters);
			addLimit(parameters);
			gxHTTPStringRequest.queryParams(parameters);
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.get();
			String all = HTTPUtility.getResponse(String.class, httpURLConnection);
			
			logger.debug("Got {}s are {}", QueryTemplate.NAME, all);
			
			JavaType type = ElementMapper.getObjectMapper().getTypeFactory().constructCollectionType(ArrayList.class, QueryTemplate.class);
			return ElementMapper.getObjectMapper().readValue(all, type);
			
		} catch(ResourceRegistryException e) {
			// logger.trace("Error Creating {}", facet, e);
			throw e;
		} catch(Exception e) {
			// logger.trace("Error Creating {}", facet, e);
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public QueryTemplate create(QueryTemplate queryTemplate) throws QueryTemplateAlreadyPresentException, ResourceRegistryException {
		try {
			String queryTemplateString = ElementMapper.marshal(queryTemplate);
			String res = create(queryTemplateString);
			return ElementMapper.unmarshal(QueryTemplate.class, res);
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public String create(String queryTemplate) throws QueryTemplateAlreadyPresentException, ResourceRegistryException {
		try {
			logger.trace("Going to create: {}", queryTemplate);
			QueryTemplate qt = ElementMapper.unmarshal(QueryTemplate.class, queryTemplate);
			
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.header(CONTENT_TYPE_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			gxHTTPStringRequest.path(qt.getName());
			
			Map<String,String> parameters = new HashMap<>();
			addIncludeMeta(parameters);
			addIncludeAllMeta(parameters);
			gxHTTPStringRequest.queryParams(parameters);
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.put(queryTemplate);
			String c = HTTPUtility.getResponse(String.class, httpURLConnection);
			
			logger.trace("{} successfully created", c);
			return c;
			
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public boolean exist(String queryTemplateName) throws ResourceRegistryException {
		try {
			logger.trace("Going to read {} with name {}", QueryTemplate.NAME, queryTemplateName);
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			gxHTTPStringRequest.path(queryTemplateName);
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.head();
			HTTPUtility.getResponse(String.class, httpURLConnection);
			return true;
		} catch (NotFoundException e) {
			return false;
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public boolean exist(QueryTemplate queryTemplate) throws ResourceRegistryException {
		return exist(queryTemplate.getName());
	}
	
	@Override
	public QueryTemplate read(QueryTemplate queryTemplate) throws QueryTemplateNotFoundException, ResourceRegistryException {
		return read(queryTemplate.getName());
	}
	
	@Override
	public QueryTemplate read(String queryTemplateName) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			String queryTemplate = readAsString(queryTemplateName);
			return ElementMapper.unmarshal(QueryTemplate.class, queryTemplate);
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public String readAsString(String queryTemplateName) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			logger.trace("Going to read {} with name {}", QueryTemplate.NAME, queryTemplateName);
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			gxHTTPStringRequest.path(queryTemplateName);
			
			Map<String,String> parameters = new HashMap<>();
			addIncludeMeta(parameters);
			addIncludeAllMeta(parameters);
			gxHTTPStringRequest.queryParams(parameters);
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.get();
			String c = HTTPUtility.getResponse(String.class, httpURLConnection);
			
			logger.debug("Got {} is {}", QueryTemplate.NAME, c);
			return c;
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public QueryTemplate update(QueryTemplate queryTemplate) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			String queryTemplateString = ElementMapper.marshal(queryTemplate);
			String res = update(queryTemplateString);
			return ElementMapper.unmarshal(QueryTemplate.class, res);
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public String update(String queryTemplate) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			logger.trace("Going to update: {}", queryTemplate);
			QueryTemplate qt = ElementMapper.unmarshal(QueryTemplate.class, queryTemplate);
			
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.header(CONTENT_TYPE_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			gxHTTPStringRequest.path(qt.getName());
			
			Map<String,String> parameters = new HashMap<>();
			addIncludeMeta(parameters);
			addIncludeAllMeta(parameters);
			gxHTTPStringRequest.queryParams(parameters);
			
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.put(queryTemplate);
			String c = HTTPUtility.getResponse(String.class, httpURLConnection);
			
			logger.trace("{} successfully updated", c);
			return c;
			
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public String runGetString(String name) throws QueryTemplateNotFoundException, ResourceRegistryException {
		return run(name, "");
	}

	@Override
	public <E extends ERElement> List<E> run(String name) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			String ret = runGetString(name);
			JavaType type = ElementMapper.getObjectMapper().getTypeFactory().constructCollectionType(ArrayList.class, ERElement.class);
			return ElementMapper.getObjectMapper().readValue(ret, type);
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}

	@Override
	public <E extends ERElement> List<E> run(QueryTemplate queryTemplate) throws QueryTemplateNotFoundException, ResourceRegistryException {
		return run(queryTemplate.getName());
	}
	
	@Override
	public String run(String name, String params) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			if(params==null || params.compareTo("")==0) {
				logger.trace("Going to run {} using default parameters", QueryTemplate.NAME);
				params = null;
			}else {
				logger.trace("Going to run {} with the following parameters {}", QueryTemplate.NAME, params);
			}
			
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.header(CONTENT_TYPE_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			gxHTTPStringRequest.path(name);
			
			includeAdditionalQueryParameters(gxHTTPStringRequest);
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.post(params);
			String c = HTTPUtility.getResponse(String.class, httpURLConnection);
			
			logger.trace("The result of the query is {}", c);
			return c;
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public <E extends ERElement> List<E> run(String name, JsonNode jsonNode) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			ObjectMapper objectMapper = new ObjectMapper();
			String ret = run(name, objectMapper.writeValueAsString(jsonNode));
			JavaType type = ElementMapper.getObjectMapper().getTypeFactory().constructCollectionType(ArrayList.class, ERElement.class);
			return ElementMapper.getObjectMapper().readValue(ret, type);
		} catch(ResourceRegistryException e) {
			throw e;
		} catch(Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	@Override
	public <E extends ERElement> List<E> run(QueryTemplate queryTemplate, JsonNode jsonNode) throws QueryTemplateNotFoundException, ResourceRegistryException {
		return run(queryTemplate.getName(), jsonNode);
	}
	
	@Override
	public boolean delete(QueryTemplate queryTemplate) throws QueryTemplateNotFoundException, ResourceRegistryException {
		return delete(queryTemplate.getName());
	}
	
	@Override
	public boolean delete(String queryTemplateName) throws QueryTemplateNotFoundException, ResourceRegistryException {
		try {
			logger.trace("Going to delete {} with name {}", QueryTemplate.NAME, queryTemplateName);
			GXHTTPStringRequest gxHTTPStringRequest = getGXHTTPStringRequest();
			gxHTTPStringRequest.header(ACCEPT_HTTP_HEADER_KEY, GXConnection.APPLICATION_JSON_CHARSET_UTF_8);
			gxHTTPStringRequest.path(QueryTemplatePath.QUERY_TEMPLATES_PATH_PART);
			gxHTTPStringRequest.path(queryTemplateName);
			
			HttpURLConnection httpURLConnection = gxHTTPStringRequest.delete();
			HTTPUtility.getResponse(String.class, httpURLConnection);
			
			boolean deleted = true;
			
			logger.info("{} with name {} {}", QueryTemplate.NAME, queryTemplateName,
					deleted ? "successfully deleted" : "was NOT deleted");
			return deleted;
		} catch(ResourceRegistryException e) {
			// logger.trace("Error Creating {}", facet, e);
			throw e;
		} catch(Exception e) {
			// logger.trace("Error Creating {}", facet, e);
			throw new RuntimeException(e);
		}
	}

}