using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Linq.Expressions;

using Pocos.Context;

using Repository.Interfaces;

namespace Repository
{
   public class BaseRepository<TEntity> : IBaseRepository<TEntity> where TEntity : class
   {

      internal IDbContext _ctx;
      internal IDbSet<TEntity> _dbSet;

      public BaseRepository(IDbContext freeWorldContext)
      {
         _ctx = freeWorldContext;
         _dbSet = _ctx.Set<TEntity>();
      }

      public virtual TEntity Create(TEntity entity)
      {
         var addedEntity = _dbSet.Add(entity);

         return addedEntity;
      }

      public virtual void Update(TEntity entity)
      {
         _dbSet.Attach(entity);
      }

      public virtual void Delete(TEntity entity)
      {
         _dbSet.Remove(entity);
      }

      public virtual IQueryable<TEntity> Get(Expression<Func<TEntity, bool>> predicate)
      {
         return _dbSet.Where(predicate);
      }

      public virtual IQueryable<TEntity> GetAll()
      {
         return _dbSet;
      }

      public virtual RepositoryQuery<TEntity> Query()
      {
         var repositoryGetFluentHelper =
             new RepositoryQuery<TEntity>(this);

         return repositoryGetFluentHelper;
      }

      internal IQueryable<TEntity> Get(Expression<Func<TEntity, bool>> filter = null,
                                       Func<IQueryable<TEntity>,
                                       IOrderedQueryable<TEntity>> orderBy = null,
                                       List<Expression<Func<TEntity, object>>>
                                       includeProperties = null,
                                       int? page = null, int? pageSize = null)
      {
         IQueryable<TEntity> query = DbSet;

         if(includeProperties != null)
         {
            includeProperties.ForEach(i => { query = query.Include(i); });
         }

         if(filter != null)
         {
            query = query.Where(filter);
         }

         if(orderBy != null)
         {
            query = orderBy(query);
         }

         if(page != null && pageSize != null)
         {
            query = query.Skip((page.Value - 1) * pageSize.Value)
                         .Take(pageSize.Value);
         }

         return query;
      }
   }
}