package service

import (
	"context"
	"time"

	"datarush/internal/competition/domain"
	"datarush/internal/competition/repository"

	"github.com/google/uuid"
)

type Service struct {
	repo repository.CompetitionRepository
}

func NewService(repo repository.CompetitionRepository) *Service {
	return &Service{repo: repo}
}

func (s *Service) CreateCompetition(ctx context.Context, comp *domain.Competition) (*domain.Competition, error) {
	now := time.Now()
	if comp.ID == uuid.Nil {
		comp.ID = uuid.New()
	}
	comp.CreatedAt = now
	comp.UpdatedAt = now

	if err := s.repo.Create(ctx, comp); err != nil {
		return nil, err
	}
	return comp, nil
}

func (s *Service) GetCompetition(ctx context.Context, id uuid.UUID) (*domain.Competition, error) {
	return s.repo.Get(ctx, id)
}

func (s *Service) EditCompetition(ctx context.Context, comp *domain.Competition) (*domain.Competition, error) {
	comp.UpdatedAt = time.Now()
	if err := s.repo.Update(ctx, comp); err != nil {
		return nil, err
	}
	return s.repo.Get(ctx, comp.ID)
}

func (s *Service) DeleteCompetition(ctx context.Context, id uuid.UUID) error {
	return s.repo.Delete(ctx, id)
}

func (s *Service) ListCompetitions(ctx context.Context, pageSize int32, pageToken int32, state *domain.CompetitionState, isParticipating *bool, searchQuery *string) ([]domain.Competition, int32, int32, error) {
	opts := repository.ListCompetitionsOptions{
		Page:            int(pageToken),
		PageSize:        int(pageSize),
		State:           state,
		IsParticipating: isParticipating,
		SearchQuery:     searchQuery,
	}

	competitions, total, err := s.repo.List(ctx, opts)
	if err != nil {
		return nil, 0, 0, err
	}

	var nextPageToken int32
	if (opts.Page+1)*opts.PageSize < total {
		nextPageToken = int32(opts.Page + 1)
	}

	return competitions, int32(total), nextPageToken, nil
}

func (s *Service) ChangeCompetitionState(ctx context.Context, id uuid.UUID, state domain.CompetitionState) (*domain.Competition, error) {
	return s.repo.ChangeState(ctx, id, state)
}