package de.dlr.shepard.neo4Core.services;
   
   import java.io.InputStream;
   import java.text.SimpleDateFormat;
   import java.util.List;
   
   import de.dlr.shepard.mongoDB.FileService;
   import de.dlr.shepard.mongoDB.NamedInputStream;
   import de.dlr.shepard.mongoDB.ShepardFile;
  import de.dlr.shepard.neo4Core.dao.FileContainerDAO;
  import de.dlr.shepard.neo4Core.dao.PermissionsDAO;
  import de.dlr.shepard.neo4Core.dao.UserDAO;
  import de.dlr.shepard.neo4Core.entities.FileContainer;
  import de.dlr.shepard.neo4Core.entities.Permissions;
  import de.dlr.shepard.neo4Core.io.FileContainerIO;
  import de.dlr.shepard.util.DateHelper;
  import de.dlr.shepard.util.PermissionType;
  import de.dlr.shepard.util.QueryParamHelper;
  import lombok.extern.slf4j.Slf4j;
  
  @Slf4j
  public class FileContainerService implements IContainerService<FileContainer, FileContainerIO> {
  
  	private FileContainerDAO fileContainerDAO = new FileContainerDAO();
  	private PermissionsDAO permissionsDAO = new PermissionsDAO();
  	private UserDAO userDAO = new UserDAO();
  	private DateHelper dateHelper = new DateHelper();
  	private FileService fileService = new FileService();
  
  	/**
  	 * Creates a FileContainer and stores it in Neo4J
  	 *
  	 * @param fileContainerIO to be stored
  	 * @param username        of the related user
  	 * @return the created FileContainer
  	 */
  	@Override
  	public FileContainer createContainer(FileContainerIO fileContainerIO, String username) {
  		var user = userDAO.find(username);
  		var toCreate = new FileContainer();
  		toCreate.setCreatedAt(dateHelper.getDate());
  		toCreate.setCreatedBy(user);
  		toCreate.setMongoId(fileService.createFileContainer());
  		toCreate.setName(fileContainerIO.getName());
  
  		var created = fileContainerDAO.createOrUpdate(toCreate);
  		permissionsDAO.createOrUpdate(new Permissions(created, user, PermissionType.Private));
  		return created;
  	}
  
  	/**
  	 * Searches the FileContainer in Neo4j
  	 *
  	 * @param id identifies the searched FileContainer
  	 * @return the FileContainer with matching id or null
  	 */
  	@Override
  	public FileContainer getContainer(long id) {
  		FileContainer fileContainer = fileContainerDAO.findByNeo4jId(id);
  		if (fileContainer == null || fileContainer.isDeleted()) {
  			log.error("File Container with id {} is null or deleted", id);
  			return null;
  		}
  		return fileContainer;
  	}
  
  	/**
  	 * Searches the database for all FileContainers
  	 *
  	 * @param params   QueryParamsHelper
  	 * @param username the name of the user
  	 * @return a list of FileContainers
  	 */
  	@Override
  	public List<FileContainer> getAllContainers(QueryParamHelper params, String username) {
  		var containers = fileContainerDAO.findAllFileContainers(params, username);
  		return containers;
  	}
  
  	/**
  	 * Deletes a FileContainer in Neo4j
  	 *
  	 * @param fileContainerId identifies the FileContainer
  	 * @param username        the deleting user
  	 * @return a boolean to determine if FileContainer was successfully deleted
  	 */
  	@Override
  	public boolean deleteContainer(long fileContainerId, String username) {
  		var user = userDAO.find(username);
  		FileContainer fileContainer = fileContainerDAO.findByNeo4jId(fileContainerId);
  		if (fileContainer == null) {
  			return false;
  		}
  		String mongoid = fileContainer.getMongoId();
  		fileContainer.setDeleted(true);
  		fileContainer.setUpdatedAt(dateHelper.getDate());
  		fileContainer.setUpdatedBy(user);
  		fileContainerDAO.createOrUpdate(fileContainer);
  		return fileService.deleteFileContainer(mongoid);
 	}
 
 	/**
 	 * Get file payload
 	 *
 	 * @param fileContainerId The container to get the payload from
 	 * @param oid             The specific file
 	 * @return a NamedInputStream
 	 */
 	public NamedInputStream getFile(long fileContainerId, String oid) {
 		var container = fileContainerDAO.findLightByNeo4jId(fileContainerId);
 		if (container == null || container.isDeleted()) {
 			log.error("File Container with id {} is null or deleted", fileContainerId);
 			return null;
 		}
 		var result = fileService.getPayload(container.getMongoId(), oid);
 		return result;
 	}
 
 	/**
 	 * Create a new file
 	 *
 	 * @param fileContainerId identifies the file container
 	 * @param fileName        the name of the new file
 	 * @param inputStream     the file itself
 	 * @return The newly created file
 	 */
 	public ShepardFile createFile(long fileContainerId, String fileName, InputStream inputStream) {
 		var fileContainer = fileContainerDAO.findByNeo4jId(fileContainerId);
 		if (fileContainer == null || fileContainer.isDeleted()) {
 			log.error("File Container with id {} is null or deleted", fileContainerId);
 			return null;
 		}
 		if (fileName == null || fileName.isBlank()) {
 			var sdf = new SimpleDateFormat("yyyyMMdd-HHmmss");
 			var dateStr = sdf.format(dateHelper.getDate());
 			fileName = "shepard-file-" + dateStr;
 		}
 		var result = fileService.createFile(fileContainer.getMongoId(), fileName, inputStream);
 		if (result == null) {
 			log.error("Failed to create shepard file");
 			return null;
 		}
 		fileContainer.addFile(result);
 		fileContainerDAO.createOrUpdate(fileContainer);
 		return result;
 	}
 
 	/**
 	 * Delete one file
 	 *
 	 * @param fileContainerId The container to get the payload from
 	 * @param oid             The specific file
 	 * @return Whether the deletion was successful or not
 	 */
 	public boolean deleteFile(long fileContainerId, String oid) {
 		var container = fileContainerDAO.findByNeo4jId(fileContainerId);
 		if (container == null || container.isDeleted())
 			return false;
 		var result = fileService.deleteFile(container.getMongoId(), oid);
 		if (result) {
 			var newFiles = container.getFiles().stream().filter(f -> !f.getOid().equals(oid)).toList();
 			container.setFiles(newFiles);
 			fileContainerDAO.createOrUpdate(container);
 		}
 		return result;
 	}
 
 }