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

namespace RouteGuideDatabaseImplement.Implements
{
    /// <summary>
    /// Хранилище для сущности "Водитель"
    /// </summary>
    public class DriverStorage : IDriverStorage
    {
        /// <summary>
        /// Получение полного списка
        /// </summary>
        /// <returns></returns>
        public List<DriverViewModel> GetFullList()
        {
            using var context = new RouteGuideDatabase();
            return context.Drivers
                .Select(x => x.GetViewModel)
                .ToList();
        }

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

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

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

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

        /// <summary>
        /// Получение элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public DriverViewModel? GetElement(DriverSearchModel model)
        {
            if (!model.Id.HasValue && string.IsNullOrEmpty(model.Phone))
            {
                return null;
            }

            using var context = new RouteGuideDatabase();
            return context.Drivers
                .FirstOrDefault(x => (!string.IsNullOrEmpty(model.Phone) && x.Phone.Contains(model.Phone)) || (model.Id.HasValue && x.Id == model.Id))
                ?.GetViewModel;
        }

        /// <summary>
        /// Добавление элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public DriverViewModel? Insert(DriverBindingModel model)
        {
            var newDriver = Driver.Create(model);
            if (newDriver == null)
            {
                return null;
            }

            using var context = new RouteGuideDatabase();
            context.Drivers.Add(newDriver);
            context.SaveChanges();
            return newDriver.GetViewModel;
        }

        /// <summary>
        /// Редактирование элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public DriverViewModel? Update(DriverBindingModel model)
        {
            using var context = new RouteGuideDatabase();
            var driver = context.Drivers.FirstOrDefault(x => x.Id == model.Id);
            if (driver == null)
            {
                return null;
            }

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

        /// <summary>
        /// Удаление элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public DriverViewModel? Delete(DriverBindingModel model)
        {
            using var context = new RouteGuideDatabase();
            var driver = context.Drivers.FirstOrDefault(x => x.Id == model.Id);
            if (driver == null)
            {
                return null;
            }

            context.Drivers.Remove(driver);
            context.SaveChanges();
            return driver.GetViewModel;
        }

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

            var element = context.Drivers.First();
            context.Drivers.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.Drivers.Count();
            if (count <= 0)
            {
                return 0;
            }

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