using EPAServeur.Context;
using EPAServeur.IServices;
using EPAServeur.Models.EP;
using IO.Swagger.DTO;
using IO.Swagger.Enum;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace EPAServeur.Services
{
	public class EpInformationService : IEpInformationService
	{
		#region Variables
		/// <summary>
		/// Accès et gestion de la base de données
		/// </summary>
		private readonly EpContext context;

		/// <summary>
		/// Accès et service collaborateur
		/// </summary>
		private readonly ICollaborateurService collaborateurService;

		/// <summary>
		/// Accès au service permettant de transformer un modèle en dto 
		/// </summary>
		private readonly ITransformDTO transformDTO;

		/// <summary>
		/// Nombre d'éléments min à afficher par page
		/// </summary>
		private readonly int minParPage = 5;

		/// <summary>
		/// Nom d'éléments max à affichar par page
		/// </summary>
		private readonly int maxParPage = 100;

		/// <summary>
		/// Nombre d'éléments à afficher par défaut par page
		/// </summary>
		private readonly int defaultParPage = 15;
		#endregion

		#region constructeur
		public EpInformationService(EpContext context, ICollaborateurService collaborateurService, ITransformDTO _transformDTO)
		{
			this.context = context;
			this.collaborateurService = collaborateurService;
			this.transformDTO = _transformDTO;
		}
		#endregion


		#region Services async
		public async Task<IEnumerable<EpInformationDTO>> GetEPEnCours(List<long?> idBUs, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			
			IEnumerable<Ep> eps = context.Ep.Where(ep => idBUs.Contains(ep.IdBu)).AsEnumerable().Where(ep => EstEpEnCours(ep.Statut));

			return await GetEpInformationDTOs(eps, asc, numPage, parPage, texte, tri, dateDebut, dateFin);
		}

		

		public async Task<int> GetEPEnCoursCount(List<long?> idBUs, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => idBUs.Contains(ep.IdBu)).AsEnumerable().Where(ep => EstEpEnCours(ep.Statut));

			return await GetEpInformationDTOsCount(eps, texte, dateDebut, dateFin);
		}

		public async Task<IEnumerable<EpInformationDTO>> GetEPEnCoursCollaborateurParticipant(Guid? idCollaborateur)
		{
			throw new NotImplementedException();
		}

		public async Task<IEnumerable<EpInformationDTO>> GetEPEnCoursReferent(Guid? idReferent, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => ep.IdReferent.Equals(idReferent)).AsEnumerable().Where(ep => EstEpEnCours(ep.Statut));

			return await GetEpInformationDTOs(eps, asc, numPage, parPage, texte, tri, dateDebut, dateFin);
		}

		public async Task<int> GetEPEnCoursReferentCount(Guid? idReferent, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => ep.IdReferent.Equals(idReferent)).AsEnumerable().Where(ep => EstEpEnCours(ep.Statut));

			return await GetEpInformationDTOsCount(eps, texte, dateDebut, dateFin);
		}

		public async Task<IEnumerable<EpInformationDTO>> GetEPSignes(List<long?> idBUs, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => idBUs.Contains(ep.IdBu)).Where(ep => ep.Statut == StatutEp.Signe);

			return await GetEpInformationDTOs(eps, asc, numPage, parPage, texte, tri, dateDebut, dateFin);
		}

		public async Task<IEnumerable<EpInformationDTO>> GetEPSignesCollaborateur(Guid? idCollaborateur)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => ep.IdCollaborateur.Equals(idCollaborateur)).Where(ep => ep.Statut.Equals(StatutEp.Signe));

			return await GetEpInformationDTOs(eps, true, 1, maxParPage, "", "", null, null);
		}

		public async Task<int> GetEPSignesCount(List<long?> idBUs, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => idBUs.Contains(ep.IdBu)).Where(ep => ep.Statut == StatutEp.Signe);

			return await GetEpInformationDTOsCount(eps, texte, dateDebut, dateFin);
		}

		public async Task<IEnumerable<EpInformationDTO>> GetEPSignesReferent(Guid? idReferent, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => ep.IdReferent.Equals(idReferent)).Where(ep => ep.Statut.Equals(StatutEp.Signe));
			return await GetEpInformationDTOs(eps, asc, numPage, parPage, texte, tri, dateDebut, dateFin);
		}

		public async Task<int> GetEPSignesReferentCount(Guid? idReferent, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			IEnumerable<Ep> eps = context.Ep.Where(ep => ep.IdReferent.Equals(idReferent)).Where(ep => ep.Statut.Equals(StatutEp.Signe));
			return await GetEpInformationDTOsCount(eps, texte, dateDebut, dateFin);
		}

		public async Task<EpInformationDTO> GetProchainEPCollaborateur(Guid? idCollaborateur)
		{
			Ep ep = context.Ep.Where(ep => ep.IdCollaborateur.Equals(idCollaborateur)).OrderBy(ep => ep.DateDisponibilite).AsEnumerable().Where(ep => ep.Statut.Equals(StatutEp.Cree) || EstEpEnCours(ep.Statut)).FirstOrDefault();
			if (ep == null)
				return null;
			IEnumerable<CollaborateurDTO> collaborateurDTOs = await collaborateurService.GetCollaborateurDTOsAsync(new List<Guid?>() { ep.IdReferent, ep.IdCollaborateur });
			return transformDTO.EpToEpDTO(ep, collaborateurDTOs);

		}
		#endregion

		#region méthodes privées

		private async Task<IEnumerable<EpInformationDTO>> GetEpInformationDTOs(IEnumerable<Ep> eps, bool? asc, int? numPage, int? parPage, string texte, string tri, DateTime? dateDebut, DateTime? dateFin)
		{
			eps = TriDate(eps, dateDebut, dateFin);

			IEnumerable<CollaborateurDTO> collaborateurDTOs = await collaborateurService.GetCollaborateurDTOsAsync(eps);
			IEnumerable<EpInformationDTO> epDTOs = eps.Select(ep => transformDTO.EpToEpDTO(ep, collaborateurDTOs));

			if (!string.IsNullOrEmpty(texte))
				epDTOs = epDTOs.Where(e => TriTexte(e, texte));

			epDTOs = TriColonne(epDTOs, tri);

			if (asc != null && asc.HasValue && !asc.Value)
				epDTOs = epDTOs.Reverse();

			return SkipAndTake(epDTOs, numPage, parPage);
		}

		private async Task<int> GetEpInformationDTOsCount(IEnumerable<Ep> eps, string texte, DateTime? dateDebut, DateTime? dateFin)
		{
			eps = TriDate(eps, dateDebut, dateFin);


			IEnumerable<CollaborateurDTO> collaborateurDTOs = await collaborateurService.GetCollaborateurDTOsAsync(eps);
			IEnumerable<EpInformationDTO> epDTOs = eps.Select(ep => transformDTO.EpToEpDTO(ep, collaborateurDTOs));

			if(!string.IsNullOrEmpty(texte))
				epDTOs = epDTOs.Where(e => TriTexte(e, texte));

			return epDTOs.Count();
		}

		private IEnumerable<Ep> TriDate(IEnumerable<Ep> eps, DateTime? dateDebut, DateTime? dateFin)
		{
			if (dateDebut.HasValue && dateDebut.Value != null)
				eps = eps.Where(ep => ep.DatePrevisionnelle >= dateDebut.Value);

			if (dateFin.HasValue && dateFin.Value != null)
				eps = eps.Where(ep => ep.DatePrevisionnelle < dateFin.Value.AddDays(1));
			return eps;
		}

		private IEnumerable<EpInformationDTO> TriColonne(IEnumerable<EpInformationDTO> epDTOs, string tri)
		{
			switch (tri)
			{
				case "agence":
					epDTOs = epDTOs.OrderBy(e => e.Collaborateur.BusinessUnit.Nom);
					break;
				case "collaborateur":
					epDTOs = epDTOs.OrderBy(e => e.Collaborateur.Nom + e.Collaborateur.Prenom);
					break;
				case "referent":
					epDTOs = epDTOs.OrderBy(e => e.Referent.Nom + e.Referent.Prenom);
					break;
				case "dateentretien":
					epDTOs = epDTOs.OrderBy(e => e.DatePrevisionnelle);
					break;
				case "typeep":
					epDTOs = epDTOs.OrderBy(e => e.Type);
					break;
				case "statutep":
					epDTOs = epDTOs.OrderBy(e => e.Statut);
					break;
				case "datearrivee":
					epDTOs = epDTOs.OrderBy(e => e.Collaborateur.DateArrivee);
					break;
				case "datedisponibilite":
					epDTOs = epDTOs.OrderBy(e => e.DateDisponibilite);
					break;
			}
			return epDTOs;
		}

		private IEnumerable<EpInformationDTO> SkipAndTake(IEnumerable<EpInformationDTO> epDTOs, int? numPage, int? parPage)
		{
			if(numPage == null ||!numPage.HasValue)
				numPage = 1;
			if (parPage == null || !parPage.HasValue || parPage < minParPage || parPage > maxParPage)
				parPage = defaultParPage;
			int skip = (numPage.Value - 1) * parPage.Value;
			return epDTOs.Skip(skip).Take(parPage.Value);

		}

		private bool EstEpEnCours(StatutEp statut)
		{
			return statut != StatutEp.Annule && statut != StatutEp.Cree && statut != StatutEp.Rejete && statut != StatutEp.Signe;
		}

		private bool TriTexte(EpInformationDTO epDTOs, string texte)
		{
			return (epDTOs.Collaborateur.Nom + " " + epDTOs.Collaborateur.Prenom).ToLower().Contains(texte.ToLower()) || (epDTOs.Collaborateur.Prenom + " " + epDTOs.Collaborateur.Nom).ToLower().Contains(texte.ToLower());
		}

		#endregion
	}
}