package eu.openaire.urls_controller.controllers;

import com.google.common.collect.HashMultimap;
import eu.openaire.urls_controller.models.Assignment;
import eu.openaire.urls_controller.models.Datasource;
import eu.openaire.urls_controller.models.Task;
import eu.openaire.urls_controller.payloads.requests.WorkerReport;
import eu.openaire.urls_controller.payloads.responces.AssignmentResponse;
//import eu.openaire.urls_controller.repositories.AssignmentRepository;
import eu.openaire.urls_controller.util.ControllerConstants;
import eu.openaire.urls_controller.util.FileUtils;
import eu.openaire.urls_controller.util.GenericUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.util.*;
import java.util.concurrent.atomic.AtomicLong;

@RestController
@RequestMapping("/urls")
public class UrlController {

    private static final Logger logger = LoggerFactory.getLogger(UrlController.class);


    private static AtomicLong assignmentCounter = new AtomicLong();    // Just for the "getTestUrls"-endpoint.

    }


    @GetMapping("")
    public ResponseEntity<?> getUrls(@RequestParam String workerId, @RequestParam int workerTasksLimit) {

        List<Task> tasks = new ArrayList<>();

        // TODO - Create the Assignment from the id-urls stored in the database up to the tasks-limit.
        Date date = new Date(); // Store it here, in order to have the same date for all current assignments.


        int tasksLimitForAssignment = ControllerConstants.ASSIGNMENTS_LIMIT;
        if ( tasksLimitForAssignment > workerTasksLimit )
            tasksLimitForAssignment = workerTasksLimit;

        List<Assignment> assignments = null; // TODO ->  // assignmentRepository.getNewAssignments(tasksLimitForAssignment);

        //Assignment assignment = new Assignment(assignmentId, tasks, workerId, date);

        // TODO - Write the Assignment details to the database and then send it to the worker.

        logger.info("Sending assignment_" + assignmentCounter.get() + " to worker with ID: " + workerId);

        return ResponseEntity.status(200).header("Content-Type", "application/json").body(new AssignmentResponse(assignmentCounter.incrementAndGet(), assignments));
    }

    @PostMapping("addWorkerReport")
    public ResponseEntity<?> addWorkerReport(@RequestBody WorkerReport workerReport) {

        if ( workerReport == null )
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).build();

        logger.debug("Received the WorkerReport:\n" + workerReport.toString());

        // TODO - Store the workerReport into the database.

        return ResponseEntity.status(HttpStatus.OK).build();
    }


    @GetMapping("test")
    public ResponseEntity<?> getTestUrls(@RequestParam String workerId, @RequestParam int assignmentsLimit) {

        try {
            new FileUtils();    // Find the input file.
        } catch (Exception e) {
            logger.error(e.getMessage());
            return ResponseEntity.status(500).body("The resource file, for the requested assignments, was not found.");
        }

        List<Assignment> assignments = new ArrayList<>();
        HashMultimap<String, String> loadedIdUrlPairs;
        boolean isFirstRun = true;
        boolean assignmentsLimitReached = false;
        Date date = new Date();

        // Start loading urls.
        while ( true ) {
            loadedIdUrlPairs = FileUtils.getNextIdUrlPairBatchFromJson(); // Take urls from jsonFile.

            if ( FileUtils.isFinishedLoading(loadedIdUrlPairs.isEmpty(), isFirstRun) )	// Throws RuntimeException which is automatically passed on.
                break;
            else
                isFirstRun = false;

            Set<Map.Entry<String, String>> pairs = loadedIdUrlPairs.entries();

            for ( Map.Entry<String,String> pair : pairs )
            {
                if ( assignments.size() >= assignmentsLimit ) {
                    assignmentsLimitReached = true;
                    break;
                }

                int randomNum = GenericUtils.getRandomNumber(1, 5);
                assignments.add(new Assignment(pair.getKey(), pair.getValue(), new Datasource("ID_" + randomNum, "NAME_" + randomNum), workerId, date));
            }// end pairs-for-loop

            if ( assignmentsLimitReached ) {
                logger.debug("Done loading urls from the inputFile as the assignmentsLimit (" + assignmentsLimit + ") was reached.");
                break;
            }
        }// end loading-while-loop

        if ( FileUtils.inputScanner.get() != null ) // Check if the initial value is null.
            FileUtils.inputScanner.get().close();

        logger.info("Sending AssignmentResponse_" +  assignmentCounter.get() + " with " + assignments.size() + " assignments (" + FileUtils.duplicateIdUrlEntries.get() + " more assignments were discarded as duplicates), to worker with ID: " + workerId);

        return ResponseEntity.status(200).header("Content-Type", "application/json").body(new AssignmentResponse(assignmentCounter.incrementAndGet(), assignments));
    }

}