using AsbCloudApp.Services;
using AsbCloudDb.Model;
using Mapster;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Caching.Memory;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace AsbCloudInfrastructure.Repository
{

    /// <summary>
    /// CRUD ñåðâèñ ñ êåøåì â îïåðàòèâêå
    /// </summary>
    /// <typeparam name="TDto"></typeparam>
    /// <typeparam name="TEntity"></typeparam>
    public class CrudCacheRepositoryBase<TDto, TEntity> : CacheBase<TEntity>, ICrudRepository<TDto>
        where TDto : AsbCloudApp.Data.IId
        where TEntity : class, IId
    {
        protected int KeySelector(TEntity entity) => entity.Id;
        protected readonly ICrudRepository<TDto> crudServiceBase;

        public CrudCacheRepositoryBase(IAsbCloudDbContext dbContext, IMemoryCache memoryCache)
        : base(dbContext, memoryCache)
        {
            crudServiceBase = new CrudRepositoryBase<TDto, TEntity>(dbContext);
        }

        public CrudCacheRepositoryBase(IAsbCloudDbContext dbContext, IMemoryCache memoryCache, Func<DbSet<TEntity>, IQueryable<TEntity>> makeQuery)
        : base(dbContext, memoryCache, makeQuery) 
        {
            crudServiceBase = new CrudRepositoryBase<TDto, TEntity>(dbContext, makeQuery);
        }

        /// <inheritdoc/>
        public virtual async Task<int> InsertAsync(TDto newItem, CancellationToken token)
        {
            var result = await crudServiceBase.InsertAsync(newItem, token);
            if (result > 0)
                DropCache();
            return result;
        }

        /// <inheritdoc/>
        public virtual async Task<int> InsertRangeAsync(IEnumerable<TDto> dtos, CancellationToken token)
        {
            var result = await crudServiceBase.InsertRangeAsync(dtos, token);
            if (result > 0)
                DropCache();
            return result;
        }

        /// <inheritdoc/>
        public virtual async Task<int> UpdateAsync(TDto dto, CancellationToken token)
        {
            var result = await crudServiceBase.UpdateAsync(dto, token);
            if (result > 0)
                DropCache();
            return result;
        }

        /// <inheritdoc/>
        public async Task<IEnumerable<TDto>> GetAllAsync(CancellationToken token)
        {
            var cache = await GetCacheAsync(token);
            var dtos = cache.Select(Convert);
            return dtos;
        }

        /// <summary>
        /// Ñèíõðîííî ïîëó÷èòü çàïèñü ïî ÈÄ
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public TDto? GetOrDefault(int id)
        {
            var cache = GetCache();
            var cacheItem = cache.FirstOrDefault(d => d.Id == id);
            if (cacheItem is null)
                return default;
            var dto = Convert(cacheItem);
            return dto;
        }

        /// <inheritdoc/>
        public async Task<TDto?> GetOrDefaultAsync(int id, CancellationToken token)
        {
            var cache = await GetCacheAsync(token);
            var cacheItem = cache.FirstOrDefault(d => d.Id == id);
            if (cacheItem is null)
                return default;
            var dto = Convert(cacheItem);
            return dto;
        }

        /// <inheritdoc/>
        public virtual async Task<int> DeleteAsync(int id, CancellationToken token)
        {
            var result = await crudServiceBase.DeleteAsync(id, token);
            if (result > 0)
                DropCache();
            return result;
        }

        protected virtual TDto Convert(TEntity src) => src.Adapt<TDto>();

        protected virtual TEntity Convert(TDto src) => src.Adapt<TEntity>();
    }

}