package eu.eudat.models.data.rda;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.jayway.jsonpath.JsonPath;
import eu.eudat.data.entities.Dataset;
import eu.eudat.logic.managers.DatasetManager;
import eu.eudat.logic.utilities.builders.XmlBuilder;
import eu.eudat.models.data.security.Principal;
import org.json.JSONArray;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import javax.xml.xpath.*;
import java.text.DateFormat;
import java.util.*;

import static java.util.stream.Collectors.groupingBy;

public class DatasetRDAExportModel {
	private static final Logger logger = LoggerFactory.getLogger(DatasetRDAExportModel.class);

	private static final ObjectMapper mapper = new ObjectMapper().configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
	private Map<String, String> multiplicityIdToFieldSetId = new HashMap<>();

	private List<String> data_quality_assurance;
	private IdRDAExportModel dataset_id;
	private String description;
	private List<DatasetDistributionRDAExportModel> distribution;
	private String issued; // Created Date, could also use finalized one.
	private List<String> keyword;
	private String language;
	private List<DatasetMetadataRDAExportModel> metadata;
	private String personal_data; // Allowed Values: yes no unknown.
	private String preservation_statement;
	private List<DatasetSecurityAndPrivacyRDAExportModel> security_and_privacy;
	private String sensitive_data; // Allowed Values: yes no unknown.
	private List<DatasetTechnicalResourceRDAExportModel> technical_resource;
	private String title;
	private String type; // Type according to: http://vocabularies.coar-repositories.org/pubby/resource_type.html

	public List<String> getData_quality_assurance() {
		return data_quality_assurance;
	}
	public void setData_quality_assurance(List<String> data_quality_assurance) {
		this.data_quality_assurance = data_quality_assurance;
	}

	public IdRDAExportModel getDataset_id() {
		return dataset_id;
	}
	public void setDataset_id(IdRDAExportModel dataset_id) {
		this.dataset_id = dataset_id;
	}

	public String getDescription() {
		return description;
	}
	public void setDescription(String description) {
		this.description = description;
	}

	public List<DatasetDistributionRDAExportModel> getDistribution() {
		return distribution;
	}
	public void setDistribution(List<DatasetDistributionRDAExportModel> distribution) {
		this.distribution = distribution;
	}

	public String getIssued() {
		return issued;
	}
	public void setIssued(String issued) {
		this.issued = issued;
	}

	public List<String> getKeyword() {
		return keyword;
	}
	public void setKeyword(List<String> keyword) {
		this.keyword = keyword;
	}

	public String getLanguage() {
		return language;
	}
	public void setLanguage(String language) {
		this.language = language;
	}

	public List<DatasetMetadataRDAExportModel> getMetadata() {
		return metadata;
	}
	public void setMetadata(List<DatasetMetadataRDAExportModel> metadata) {
		this.metadata = metadata;
	}

	public String getPersonal_data() {
		return personal_data;
	}
	public void setPersonal_data(String personal_data) {
		this.personal_data = personal_data;
	}

	public String getPreservation_statement() {
		return preservation_statement;
	}
	public void setPreservation_statement(String preservation_statement) {
		this.preservation_statement = preservation_statement;
	}

	public List<DatasetSecurityAndPrivacyRDAExportModel> getSecurity_and_privacy() {
		return security_and_privacy;
	}
	public void setSecurity_and_privacy(List<DatasetSecurityAndPrivacyRDAExportModel> security_and_privacy) {
		this.security_and_privacy = security_and_privacy;
	}

	public String getSensitive_data() {
		return sensitive_data;
	}
	public void setSensitive_data(String sensitive_data) {
		this.sensitive_data = sensitive_data;
	}

	public List<DatasetTechnicalResourceRDAExportModel> getTechnical_resource() {
		return technical_resource;
	}
	public void setTechnical_resource(List<DatasetTechnicalResourceRDAExportModel> technical_resource) {
		this.technical_resource = technical_resource;
	}

	public String getTitle() {
		return title;
	}
	public void setTitle(String title) {
		this.title = title;
	}

	public String getType() {
		return type;
	}
	public void setType(String type) {
		this.type = type;
	}


	public DatasetRDAExportModel fromDataModel(Dataset dataset, DatasetManager datasetManager, Principal principal) {
		// Map of template Ids to rda values.
		JSONObject jObject = new JSONObject(dataset.getProperties());
		Map<String, Object> templateIdsToValues = jObject.toMap();

		/*--------- Building dataset rda export model ---------*/
		DatasetRDAExportModel datasetRDAExportModel = new DatasetRDAExportModel();
		datasetRDAExportModel.setDataset_id(new IdRDAExportModel(dataset.getId().toString(), "other"));
		if (dataset.getDescription() != null) datasetRDAExportModel.setDescription(dataset.getDescription().replace("\n", " "));
		datasetRDAExportModel.setIssued(DateFormat.getDateInstance(DateFormat.SHORT).format(dataset.getCreated()));
		datasetRDAExportModel.setLanguage("en"); // mock data
		datasetRDAExportModel.setTitle(dataset.getLabel());

		// Transform the answered dataset description to json so we can parse it and fill the rda model.
		JSONObject datasetDescriptionJson = null;
		try {
			String jsonResult = mapper.writeValueAsString(datasetManager.getSingle(dataset.getId().toString(), principal).getDatasetProfileDefinition());
			datasetDescriptionJson = new JSONObject(jsonResult);
		} catch (JsonProcessingException e) {
			logger.error(e.getMessage(), e);
		}
		setMultiplicityIdToFieldSetId(datasetDescriptionJson);

		/*--------- Building personal data. ---------*/
		String personalData = buildSingleProperties("dataset.personal_data", datasetDescriptionJson, templateIdsToValues);
		if (personalData != null) {
			datasetRDAExportModel.setPersonal_data(personalData);
		} else {
			datasetRDAExportModel.setPersonal_data("unknown");
		}

		/*--------- Building preservation statement. ---------*/
		datasetRDAExportModel.setPreservation_statement(buildSingleProperties("dataset.preservation_statement", datasetDescriptionJson, templateIdsToValues));

		/*--------- Building sensitive data. ---------*/
		String sensitiveData = buildSingleProperties("dataset.sensitive_data", datasetDescriptionJson, templateIdsToValues);
		if (personalData != null) {
			datasetRDAExportModel.setSensitive_data(sensitiveData);
		} else {
			datasetRDAExportModel.setSensitive_data("unknown");
		}

		/*--------- Building type. ---------*/
		datasetRDAExportModel.setType(buildSingleProperties("dataset.type", datasetDescriptionJson, templateIdsToValues));

		/*--------- Building data_quality_assurance. ---------*/
		datasetRDAExportModel.setData_quality_assurance(buildDataQualityAssurance(datasetDescriptionJson, templateIdsToValues, dataset.getProfile().getDefinition()));

		/*--------- Building distribution. ---------*/
		datasetRDAExportModel.setDistribution(buildDistribution(datasetDescriptionJson, templateIdsToValues, dataset.getProfile().getDefinition()));

		/*--------- Building keywords. ---------*/
		datasetRDAExportModel.setKeyword(buildKeywords(datasetDescriptionJson, templateIdsToValues, dataset.getProfile().getDefinition()));

		/*--------- Building metadata items. ---------*/
		datasetRDAExportModel.setMetadata(buildMetadata(datasetDescriptionJson, templateIdsToValues, dataset.getProfile().getDefinition()));

		/*--------- Building security and privacy items. ---------*/
		datasetRDAExportModel.setSecurity_and_privacy(buildSecurityAndPrivacy(datasetDescriptionJson, templateIdsToValues, dataset.getProfile().getDefinition()));

		/*--------- Building technical_resource. ---------*/
		datasetRDAExportModel.setTechnical_resource(buildTechnicalResource(datasetDescriptionJson, templateIdsToValues, dataset.getProfile().getDefinition()));

		return datasetRDAExportModel;
	}

	private String buildSingleProperties(String rdaKey, JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues) {
		String expression = "$..fields[*][?(@.rdaProperty == \"" + rdaKey + "\" )].id";
		List<String> list = jsonValueListFromExpression(datasetDescriptionJson, expression);
		if (!list.isEmpty()) {
			return templateIdsToValues.get(list.get(0)).toString();
		} else {
			return null;
		}
	}

	private List<String> buildDataQualityAssurance(JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues, String datasetProfileDefinition) {
		List<RdaField> dataQualityFields = getRDAFieldsFromJson(datasetDescriptionJson, new String[]{"dataset.data_quality_assurance"}, datasetProfileDefinition);
		for (RdaField rdaField : dataQualityFields) {
			rdaField.setRdaValue(templateIdsToValues.get(rdaField.getFieldId()).toString());
		}
		List<String> dataQualityAssuranceList = new LinkedList<>();
		for (RdaField rdaField : dataQualityFields) {
			dataQualityAssuranceList.add(rdaField.getRdaValue());
		}

		return dataQualityAssuranceList;
	}

	private List<DatasetDistributionRDAExportModel> buildDistribution(JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues, String datasetProfileDefinition) {
		DatasetDistributionRDAExportModel distributionModel = new DatasetDistributionRDAExportModel();
		distributionModel.setAccess_url(buildSingleProperties("dataset.distribution.access_url", datasetDescriptionJson, templateIdsToValues));
		distributionModel.setAvailable_till(buildSingleProperties("dataset.distribution.available_till", datasetDescriptionJson, templateIdsToValues));
		distributionModel.setByte_size(buildSingleProperties("dataset.distribution.byte_size", datasetDescriptionJson, templateIdsToValues));
		distributionModel.setData_access(buildSingleProperties("dataset.distribution.data_access", datasetDescriptionJson, templateIdsToValues));
		distributionModel.setDescription(buildSingleProperties("dataset.distribution.description", datasetDescriptionJson, templateIdsToValues));
		distributionModel.setDownload_url(buildSingleProperties("dataset.distribution.download_url", datasetDescriptionJson, templateIdsToValues));
		distributionModel.setTitle(buildSingleProperties("dataset.distribution.title", datasetDescriptionJson, templateIdsToValues));

		/*--------- Building format. ---------*/


		// We currently support the return of only one distribution.
		List<DatasetDistributionRDAExportModel> distributionList = new LinkedList<>();
		if (distributionModel.isValid()) {
			distributionList.add(distributionModel);
		} else {
			DatasetDistributionRDAExportModel model = new DatasetDistributionRDAExportModel();
			model.setDescription("Distribution data was not valid");
			distributionList.add(model);
		}

		return distributionList;
	}

	private List<String> buildKeywords(JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues, String datasetProfileDefinition) {
		List<RdaField> keywordFields = getRDAFieldsFromJson(datasetDescriptionJson, new String[]{"dataset.keyword"}, datasetProfileDefinition);
		for (RdaField rdaField : keywordFields) {
			rdaField.setRdaValue(templateIdsToValues.get(rdaField.getFieldId()).toString());
		}
		List<String> keywordsList = new LinkedList<>();
		for (RdaField rdaField : keywordFields) {
			keywordsList.add(rdaField.getRdaValue());
		}

		return keywordsList;
	}

	private List<DatasetMetadataRDAExportModel> buildMetadata(JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues, String datasetProfileDefinition) {
		List<RdaField> metadataFields = getRDAFieldsFromJson(datasetDescriptionJson,
				new String[]{"dataset.metadata.metadata_standard_id.type", "dataset.metadata.metadata_standard_id.identifier", "dataset.metadata.description", "dataset.metadata.language", "dataset.metadata.metadata_standard_id"},
				datasetProfileDefinition);

		// Adding rdaValue and FieldSetIds on metadataFields.
		for (RdaField rdaField : metadataFields) {
			rdaField.setRdaValue(templateIdsToValues.get(rdaField.getFieldId()).toString());
		}
		// Group metadataFields based on their field set id.
		Map<String, List<RdaField>> groupedMetadataFields = metadataFields.stream().collect(groupingBy(RdaField::getFieldSetId));

		// Creating the metadata.
		List<DatasetMetadataRDAExportModel> metadataRDAExportModelList = new LinkedList<>();
		for (String fieldSetId : groupedMetadataFields.keySet()) {
			DatasetMetadataRDAExportModel metadataRda = new DatasetMetadataRDAExportModel();
			for (RdaField rdaField : groupedMetadataFields.get(fieldSetId)) {
				if (rdaField.getRdaProperty().equals("dataset.metadata.metadata_standard_id.identifier")) {
					if (metadataRda.getMetadata_standard_id() != null) {
						metadataRda.getMetadata_standard_id().setIdentifier(rdaField.getRdaValue());
					} else {
						metadataRda.setMetadata_standard_id(new IdRDAExportModel(rdaField.getRdaValue(), "other"));
					}
				}
				if (rdaField.getRdaProperty().equals("dataset.metadata.metadata_standard_id.type")) {
					if (metadataRda.getMetadata_standard_id() != null) {
						metadataRda.getMetadata_standard_id().setType(rdaField.getRdaValue());
					} else {
						metadataRda.setMetadata_standard_id(new IdRDAExportModel("", rdaField.getRdaValue()));
					}
				}
				if (rdaField.getRdaProperty().equals("dataset.metadata.description")) {
					metadataRda.setDescription(rdaField.getRdaValue());
				}
				if (rdaField.getRdaProperty().equals("dataset.metadata.language")) {
					metadataRda.setLanguage(rdaField.getRdaValue());
				}
				if (rdaField.getRdaProperty().equals("dataset.metadata.metadata_standard_id") && !rdaField.getRdaValue().isEmpty()) {
					JSONArray jsonArray = new JSONArray(rdaField.getRdaValue());
					for (int i = 0; i < jsonArray.length(); i++) {
						JSONObject jsonObject = jsonArray.getJSONObject(i);
						Map<String, Object> jsonObjectMap = jsonObject.toMap();
						DatasetMetadataRDAExportModel metadataRda1 = new DatasetMetadataRDAExportModel();
//						metadataRda1.setMetadata_standard_id(new IdRDAExportModel(jsonObjectMap.get("label").toString(), jsonObjectMap.get("source").toString()));
						metadataRda1.setMetadata_standard_id(new IdRDAExportModel(jsonObjectMap.get("uri").toString(), "url"));
						metadataRDAExportModelList.add(metadataRda1);
					}
				}
			}
			if (metadataRda.isValid()) {
				metadataRDAExportModelList.add(metadataRda);
			}
		}

		return new LinkedList<>(metadataRDAExportModelList);
	}

	private List<DatasetSecurityAndPrivacyRDAExportModel> buildSecurityAndPrivacy(JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues, String datasetProfileDefinition) {
		List<RdaField> secAndPrFields = getRDAFieldsFromJson(
				datasetDescriptionJson,
				new String[]{"dataset.security_and_privacy.description", "dataset.security_and_privacy.title", "dataset.security_and_privacy"},
				datasetProfileDefinition);
		for (RdaField rdaField : secAndPrFields) {
			rdaField.setRdaValue(templateIdsToValues.get(rdaField.getFieldId()).toString());
		}
		Map<String, List<RdaField>> groupedSecurityAndPrivacyFields = secAndPrFields.stream().collect(groupingBy(RdaField::getFieldSetId));

		List<DatasetSecurityAndPrivacyRDAExportModel> securityAndPrivacyRDAExportModelList = new LinkedList<>();
		for (String fieldSetId : groupedSecurityAndPrivacyFields.keySet()) {
			DatasetSecurityAndPrivacyRDAExportModel securityAndPrivacyModel = new DatasetSecurityAndPrivacyRDAExportModel();
			for (RdaField rdaField : groupedSecurityAndPrivacyFields.get(fieldSetId)) {
				if (rdaField.getRdaProperty().equals("dataset.security_and_privacy.description")) {
					securityAndPrivacyModel.setDescription(rdaField.getRdaValue());
				}
				if (rdaField.getRdaProperty().equals("dataset.security_and_privacy.title")) {
					securityAndPrivacyModel.setTitle(rdaField.getRdaValue());
				}
				if (rdaField.getRdaProperty().equals("dataset.security_and_privacy")) {
					JSONArray jsonArray = new JSONArray(rdaField.getRdaValue());
					for (int i = 0; i < jsonArray.length(); i++) {
						JSONObject jsonObject = jsonArray.getJSONObject(i);
						Map<String, Object> jsonObjectMap = jsonObject.toMap();
						DatasetSecurityAndPrivacyRDAExportModel secAndPrivacy = new DatasetSecurityAndPrivacyRDAExportModel(jsonObjectMap.get("label").toString(), jsonObjectMap.get("source").toString());
						securityAndPrivacyRDAExportModelList.add(secAndPrivacy);
					}
				}
			}
			securityAndPrivacyRDAExportModelList.add(securityAndPrivacyModel);
		}

		return securityAndPrivacyRDAExportModelList;
	}

	private List<DatasetTechnicalResourceRDAExportModel> buildTechnicalResource(JSONObject datasetDescriptionJson, Map<String, Object> templateIdsToValues, String datasetProfileDefinition) {
		List<RdaField> dataQualityFields = getRDAFieldsFromJson(datasetDescriptionJson,
				new String[]{"dataset.technical_resource.technical_resource", "dataset.technical_resource.technical_resource.description", "dataset.technical_resource.technical_resource.name"},
				datasetProfileDefinition);
		for (RdaField rdaField : dataQualityFields) {
			rdaField.setRdaValue(templateIdsToValues.get(rdaField.getFieldId()).toString());
		}
		List<DatasetTechnicalResourceRDAExportModel> technicalResourceList = new LinkedList<>();
		Map<String, List<RdaField>> groupedDataQualityFields = dataQualityFields.stream().collect(groupingBy(RdaField::getFieldSetId));
		for (String fieldSetId : groupedDataQualityFields.keySet()) {
			DatasetTechnicalResourceRDAExportModel technicalResourceModel = new DatasetTechnicalResourceRDAExportModel();
			for (RdaField rdaField : groupedDataQualityFields.get(fieldSetId)) {
				if (rdaField.getRdaProperty().equals("dataset.technical_resource.technical_resource.description")) {
					technicalResourceModel.setDescription(rdaField.getRdaValue());
				}
				if (rdaField.getRdaProperty().equals("dataset.technical_resource.technical_resource.name")) {
					technicalResourceModel.setName(rdaField.getRdaValue());
				}
				if (rdaField.getRdaProperty().equals("dataset.security_and_privacy")) {
					JSONArray jsonArray = new JSONArray(rdaField.getRdaValue());
					for (int i = 0; i < jsonArray.length(); i++) {
						JSONObject jsonObject = jsonArray.getJSONObject(i);
						Map<String, Object> jsonObjectMap = jsonObject.toMap();
						DatasetTechnicalResourceRDAExportModel technicalResource = new DatasetTechnicalResourceRDAExportModel(jsonObjectMap.get("label").toString(), jsonObjectMap.get("label").toString());
						technicalResourceList.add(technicalResource);
					}
				}
			}
			technicalResourceList.add(technicalResourceModel);
		}

		return technicalResourceList;
	}

	private void setMultiplicityIdToFieldSetId(JSONObject json) {
		String multiplicityItemsFieldSetIdExp = "$..multiplicityItems[*].id";
		List<String> multiplicityItemsFieldSetIdList = jsonValueListFromExpression(json, multiplicityItemsFieldSetIdExp);
		for (String fieldSetId : multiplicityItemsFieldSetIdList) {
			String fieldsFromFieldSetIdExp = "$..multiplicityItems[*][?(@.id == \""+ fieldSetId +"\")].fields[*].id";
			List<String> fieldsIdList = jsonValueListFromExpression(json, fieldsFromFieldSetIdExp);
			for (String fieldId : fieldsIdList) {
				this.multiplicityIdToFieldSetId.put(fieldId, fieldSetId);
			}
		}
	}

	private List<RdaField> getRDAFieldsFromJson(JSONObject json, String[] rdaKey, String datasetProfileDefinition) {
		List<RdaField> rdaFields = new LinkedList<>();
		for (String key : rdaKey) {
			String fieldIdExpression = "$..fields[*][?(@.rdaProperty == \"" + key + "\" )].id";
			List<String> listFromExpression = jsonValueListFromExpression(json, fieldIdExpression);
			for (String fieldId : listFromExpression) {
				RdaField rdaField = new RdaField();
				rdaField.setRdaProperty(key);
				rdaField.setFieldId(fieldId);
				if (fieldId.startsWith("multiple_")) {
					rdaField.setFieldSetId(this.multiplicityIdToFieldSetId.get(fieldId));
				} else {
					rdaField.setFieldSetId(getFieldSetIdForFieldFromXML(datasetProfileDefinition, fieldId));
				}
				rdaFields.add(rdaField);
			}
		}
		return rdaFields;
	}

	private List<String> jsonValueListFromExpression(JSONObject json, String expression) {
		net.minidev.json.JSONArray jsonArray = JsonPath.parse(json.toString()).read(expression);
		List<String> valueList = new LinkedList<>();
		for (Object o : jsonArray) {
			valueList.add(o.toString());
		}
		return valueList;
	}

	private String getFieldSetIdForFieldFromXML(String datasetProfileDefinition, String fieldId) {
		String fieldSetIdExpression = "//field[@id ='" + fieldId + "']/ancestor::fieldSet/@id";
		List<String> listFromExpression = xmlValueListFromExpression(datasetProfileDefinition, fieldSetIdExpression);
		if (listFromExpression.size() == 1) return listFromExpression.get(0);
		return null;
	}

	private List<String> xmlValueListFromExpression(String xml, String expression) {
		List<String> valuesList = new LinkedList<>();
		Document document = XmlBuilder.fromXml(xml);
		XPathFactory xpathFactory = XPathFactory.newInstance();
		XPath xpath = xpathFactory.newXPath();
		try {
			XPathExpression expr = xpath.compile(expression);
			NodeList nodeList = (NodeList) expr.evaluate(document, XPathConstants.NODESET);
			for (int i = 0; i < nodeList.getLength(); i++) {
				Node node = nodeList.item(i);
				valuesList.add(node.getNodeValue());
			}
		} catch (XPathExpressionException e) {
			logger.error(e.getMessage(), e);
		}

		return valuesList;
	}
}