using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using VetClinicBusinessLogic.BindingModels;
using VetClinicBusinessLogic.Interfaces;
using VetClinicBusinessLogic.ViewModels;
using VetClinicDatabaseImplement.Models;
using Microsoft.EntityFrameworkCore;


namespace VetClinicDatabaseImplement.Implement
{
    public class VisitStorage : IVisitStorage
    {
        public List<VisitViewModel> GetFullList()
        {
            using var context = new VetClinicDatabase();
            return context.Visits
             .Include(rec => rec.VisitServices)
             .ThenInclude(rec => rec.Service)
             .Include(x => x.Client)
             .Include(x => x.Employee)
            .Select(CreateModel)
            .ToList();
        }
        public List<VisitViewModel> GetFilteredList(VisitBindingModel model)
        {
            if (model == null)
            {
                return null;
            }
            using var context = new VetClinicDatabase();
            return context.Visits.Include(rec => rec.VisitServices)
            .ThenInclude(rec => rec.Service)
             .Include(x => x.Client)
             .Include(x => x.Employee).Where(rec => rec.ClientId == model.ClientId)
            .Select(CreateModel)

            .ToList();
        }
        public List<VisitViewModel> GetFilteredListEmployee(VisitBindingModel model)
        {
            if (model == null)
            {
                return null;
            }
            using var context = new VetClinicDatabase();
            return context.Visits.Include(rec => rec.VisitServices)
            .ThenInclude(rec => rec.Service)
             .Include(x => x.Client)
             .Include(x => x.Employee).Where(rec => rec.EmployeeId == model.EmployeeId)
            .Select(CreateModel)

            .ToList();
        }
        public List<VisitViewModel> GetFilteredListDate(VisitBindingModel model)
        {
            if (model == null)
            {
                return null;
            }
            using var context = new VetClinicDatabase();
            return context.Visits.Include(rec => rec.VisitServices)
            .ThenInclude(rec => rec.Service)
             .Include(x => x.Client)
             .Include(x => x.Employee).Where(rec => rec.Id.Equals(model.Id) || rec.DateVisit >= model.DateFrom && rec.DateVisit <= model.DateTo)
            .Select(CreateModel)

            .ToList();
        }
        public VisitViewModel GetElement(VisitBindingModel model)
        {
            if (model == null)
            {
                return null;
            }
            using var context = new VetClinicDatabase();
            var visit = context.Visits
                .Include(rec => rec.VisitServices)
            .ThenInclude(rec => rec.Service)
             .Include(x => x.Client)
             .Include(x => x.Employee)
            .FirstOrDefault(rec => rec.Id == model.Id)
            ;
            if (visit == null)
            {
                return null;
            }
            return CreateModel(visit);
        }
        public void Insert(VisitBindingModel model)
        {
            using var context = new VetClinicDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                CreateModel(model, new Visit(), context);
                context.SaveChanges();
                transaction.Commit();
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
                transaction.Rollback();
                throw;
            }
        }
        public void Update(VisitBindingModel model)
        {
            using var context = new VetClinicDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var element = context.Visits.FirstOrDefault(rec => rec.Id ==
                model.Id);
                if (element == null)
                {
                    throw new Exception("Элемент не найден");
                }
                CreateModel(model, element, context);
                context.SaveChanges();
                transaction.Commit();
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
                transaction.Rollback();
                throw;
            }
        }
        public void Delete(VisitBindingModel model)
        {
            using var context = new VetClinicDatabase();
            Visit element = context.Visits.FirstOrDefault(rec => rec.Id ==
            model.Id);
            if (element != null)
            {
                context.Visits.Remove(element);
                context.SaveChanges();
            }
            else
            {
                throw new Exception("Элемент не найден");
            }
        }
        private static Visit CreateModel(VisitBindingModel model, Visit visit,
       VetClinicDatabase context)
        {
            visit.DateVisit = model.VisitsDate;
            visit.ClientId = model.ClientId;
            visit.EmployeeId = model.EmployeeId;
            visit.Sum = model.Sum;
            if (visit.Id == 0)
            {
                context.Visits.Add(visit);
                context.SaveChanges();
            }
            if (model.Id != 0)
            {
                var visitServices = context.VisitServices.Where(rec =>
               rec.VisitId == model.Id).ToList();
                // удалили те, которых нет в модели
                context.VisitServices.RemoveRange(visitServices.Where(rec =>
               !model.VisitServices.ContainsKey(rec.VisitId)).ToList());
                context.SaveChanges();
                context.SaveChanges();
            }
            // добавили новые
            foreach (var pc in model.VisitServices)
            {
                context.VisitServices.Add(new VisitService
                {
                    VisitId = visit.Id,
                    ServiceId = pc.Key,
                });
                var temp = context.VisitServices;
                context.SaveChanges();
            }
            return visit;
        }
        private static VisitViewModel CreateModel(Visit visit)
        {
            return new VisitViewModel
            {
                Id = visit.Id,
                ClientName = visit.Client.Name,
                EmployeeName = visit?.Employee?.Name,
                ClientId = visit.ClientId,
                EmployeeId = visit?.EmployeeId,
                Sum = visit.Sum,
                VisitsDate = visit.DateVisit,
                VisitServices = visit.VisitServices
            .ToDictionary(recPC => recPC.ServiceId,
            recPC => recPC.Service?.Name)
            };
        }
    }
}