namespace Diligent.WebAPI.Business.Services
{
    public class SelectionProcessService : ISelectionProcessService
    {
        private readonly DatabaseContext _context;
        private readonly IMapper _mapper;
        private readonly ILogger<SelectionProcessService> _logger;

        public SelectionProcessService(DatabaseContext context, IMapper mapper, ILogger<SelectionProcessService> logger)
        {
            _context = context;
            _mapper = mapper;
            _logger = logger;
        }

        public async Task<List<SelectionProcessResposneDto>> GetAllAsync()
        {
            _logger.LogInformation("Start getting all Selection Processes");
            _logger.LogInformation("Getting data from DB");
            var fromDB = await _context.SelectionProcesses.ToListAsync();
            _logger.LogInformation($"Received {fromDB.Count} processes from db.");
            _logger.LogInformation($"Mapping received ads to SelectionProcessResposneDto");
            var result = _mapper.Map<List<SelectionProcessResposneDto>>(fromDB);
            _logger.LogInformation($"Processes has been mapped and received to client: {result.Count} mapped processes");
            return result;
        }
        public async Task<bool> FinishSelectionProcess(SelectionProcessCreateDto model)
        {
            _logger.LogInformation($"Start finishing selection process with {model.Id}");
            var sp = await _context.SelectionProcesses.FindAsync(model.Id);

            if (sp is null)
            {
                _logger.LogError($"Process with id = {model.Id} not found");
                throw new EntityNotFoundException("Selection process not found");
            }

            _logger.LogError($"Changing status for {model.Id}");
            sp.Status = "Odrađen";

            _logger.LogError($"Skipping throught levels to come to next level");
            var nextLevel = _context.SelectionLevels.AsEnumerable()
                .SkipWhile(obj => obj.Id != sp.SelectionLevelId)
                .Skip(1).First();

            if (nextLevel is null)
            {
                _logger.LogError($"Applicant is in the last selection level");
                throw new EntityNotFoundException("Candidate came to the last selection level");
            }

            SelectionProcess newProcess = new SelectionProcess
            {
                Name = model.Name,
                SelectionLevelId = nextLevel.Id,
                Status = "Čeka na zakazivanje",
                ApplicantId = sp.ApplicantId,
                SchedulerId = model.SchedulerId
            };
            _context.SelectionProcesses.Add(newProcess);
            _logger.LogError($"Create and add new selection process");
            var result = await _context.SaveChangesAsync() > 0;
            _logger.LogError($"Saved changes to db");
            return result;
        }
    }
}