package com.plannaplan.services;

import java.util.Iterator;
import java.util.List;
import java.util.Optional;
import java.util.stream.Collectors;

import com.plannaplan.entities.Assignment;
import com.plannaplan.entities.Commision;
import com.plannaplan.entities.User;
import com.plannaplan.repositories.AssignmentRepository;
import com.plannaplan.repositories.CommisionRepository;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 * Service of CommisionService which can save commision, get user's commisions,
 * get newest user's commision, get ammount of commisions.
 */

@Service
public class CommisionService {
    @Autowired
    private CommisionRepository repo;
    @Autowired
    private AssignmentRepository aRepository;

    public CommisionService() {
    }

    /**
     * save to database commision. It also checks for missing assignments from
     * previous commision (you can not get rid of accepted assignment)
     * 
     * @param commision to save to db
     * @return Commision instance with id from database
     */
    public Commision save(Commision commision) {
        Optional<Commision> lastCommision = this.getNewestCommision(commision.getCommisionOwner());
        if (lastCommision.isPresent()) {

            final List<Assignment> assignments = commision.getAssignments();
            List<Long> newAssignments = null;
            if (assignments != null) {
                newAssignments = assignments.stream().map(Assignment::getId).collect(Collectors.toList());
            }
            final Commision lastCom = lastCommision.get();
            lastCom.getAssignments().forEach(assignment -> {
                assignment.setPastAssignment(true);
                this.aRepository.save(assignment);
            });

            final List<Assignment> lastComAssignments = lastCom.getAssignments();
            if (newAssignments != null) {
                Iterator<Assignment> newAssignmentsIterator = lastComAssignments.iterator();

                while (newAssignmentsIterator.hasNext()) {
                    final Assignment a = newAssignmentsIterator.next();

                    if (!newAssignments.contains(a.getId()) && a.isAccepted()) {
                        final Assignment assignment = Assignment.getNewFromAssignment(a, commision);
                        this.aRepository.save(assignment);
                    }
                }

            }

        }
        this.repo.save(commision);
        return commision;

    }

    /**
     * gets user commisions
     * 
     * @param user owner of commisions
     * @return list of user commisions
     */
    public List<Commision> getUsersCommisions(User user) {
        return this.repo.getUsers(user.getId());
    }

    /**
     * get newest commision ov given user
     * 
     * @param user owener of commision we attemp to get
     * @return optional if commition was found
     */
    public Optional<Commision> getNewestCommision(User user) {
        return this.repo.getNewestCommision(user.getId()).stream().findFirst();
    }

    /**
     * get ammpounts of commisions
     * 
     * @return long - ammounts of commisions (all even from history, not only
     *         cutrrent one)
     */
    public long getCommisionsAmmount() {
        return this.repo.count();
    }
}