using RouteGuideContracts.BindingModels;
using RouteGuideContracts.SearchModels;
using RouteGuideContracts.StoragesContracts;
using RouteGuideContracts.ViewModels;
using RouteGuideDatabaseImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace RouteGuideDatabaseImplement.Implements
{
    /// <summary>
    /// Хранилище для сущности "Остановка"
    /// </summary>
    public class StopStorage : IStopStorage
    {
        /// <summary>
        /// Получение полного списка
        /// </summary>
        /// <returns></returns>
        public List<StopViewModel> GetFullList()
        {
            using var context = new RouteGuideDatabase();
            return context.Stops
                .Select(x => x.GetViewModel)
                .ToList();
        }

        /// <summary>
        /// Получение фильтрованного списка
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public List<StopViewModel> GetFilteredList(StopSearchModel model)
        {
            if (string.IsNullOrEmpty(model.Name))
            {
                return new();
            }

            using var context = new RouteGuideDatabase();
            return context.Stops
                .Where(x => x.Name.Contains(model.Name))
                .Select(x => x.GetViewModel)
                .ToList();
        }

        /// <summary>
        /// Получить список из заданного количества элементов
        /// </summary>
        /// <param name="count"></param>
        /// <returns></returns>
        public List<StopViewModel> GetList(int count)
        {
            if (count <= 0)
            {
                return new();
            }

            using var context = new RouteGuideDatabase();
            return context.Stops
                .Take(count)
                .Select(x => x.GetViewModel)
                .ToList();
        }

        /// <summary>
        /// Получение элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public StopViewModel? GetElement(StopSearchModel model)
        {
            if (model.Id == null && string.IsNullOrEmpty(model.Name))
            {
                return null;
            }

            using var context = new RouteGuideDatabase();
            return context.Stops
                .FirstOrDefault(x => (!string.IsNullOrEmpty(model.Name) && x.Name.Contains(model.Name)) || (model.Id != null && x.Id.Equals(model.Id)))
                ?.GetViewModel;
        }

        /// <summary>
        /// Добавление элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public StopViewModel? Insert(StopBindingModel model)
        {
            var newStop = Stop.Create(model);
            if (newStop == null)
            {
                return null;
            }

            using var context = new RouteGuideDatabase();
            context.Stops.Add(newStop);
            context.SaveChanges();
            return newStop.GetViewModel;
        }

        /// <summary>
        /// Редактирование элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public StopViewModel? Update(StopBindingModel model)
        {
            using var context = new RouteGuideDatabase();
            var stop = context.Stops.FirstOrDefault(x => x.Id.Equals(model.Id));
            if (stop == null)
            {
                return null;
            }

            stop.Update(model);
            context.SaveChanges();
            return stop.GetViewModel;
        }

        /// <summary>
        /// Удаление элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public StopViewModel? Delete(StopBindingModel model)
        {
            using var context = new RouteGuideDatabase();
            var stop = context.Stops.FirstOrDefault(x => x.Id.Equals(model.Id));
            if (stop == null)
            {
                return null;
            }

            context.Stops.Remove(stop);
            context.SaveChanges();
            return stop.GetViewModel;
        }

        /// <summary>
        /// Удаление записи
        /// </summary>
        /// <returns></returns>
        public StopViewModel? Delete()
        {
            using var context = new RouteGuideDatabase();
            if (!context.Stops.Any())
            {
                return null;
            }

            var element = context.Stops.First();
            context.Stops.Remove(element);
            context.SaveChanges();
            return element.GetViewModel;
        }

        /// <summary>
        /// Удаление всех элементов
        /// </summary>
        /// <returns></returns>
        public int Clear()
        {
            using var context = new RouteGuideDatabase();
            int count = context.Stops.Count();
            if (count <= 0)
            {
                return 0;
            }

            context.Stops.RemoveRange(context.Stops);
            context.SaveChanges();
            return count;
        }
    }
}