using Microsoft.EntityFrameworkCore;
using Mini.Common;
using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Linq.Expressions;
using System.Text;

namespace Mini.Model
{
    public class EfRepository<T> : EfRepositoryBase<T> where T : BaseEntity 
    {
        private readonly DbContext _context;
        private DbSet<T> _entities;
        protected EfRepository(DbContext context)
        {
            this._context = new crmContext();
        }

        protected virtual DbSet<T> Entities
        {
            get
            {
                if (_entities == null)
                    _entities = _context.Set<T>();
                return _entities;
            }
        }

        public override T Get(Expression<Func<T, bool>> @where)
        {
            return this.Entities.FirstOrDefault(where);
        }

        public override IQueryable<T> GetList()
        {
            return GetList(null);
        }

        public override IQueryable<T> GetList(Expression<Func<T, bool>> @where)
        {
            if (where != null)
            {
                return this.Entities.Where(where).AsNoTracking();
            }
            return this.Entities;
        }

        public override IQueryable<T> GetList<TOrderBy>(Expression<Func<T, bool>> @where, Expression<Func<T, TOrderBy>> orderBy = null, SortOrder sortOrder = SortOrder.Descending)
        {
            if (orderBy == null)
            {
                return this.Entities.Where(where);
            }
            else
            {
                if (sortOrder == SortOrder.Descending)
                    return this.Entities.Where(where).OrderByDescending(orderBy);
                else
                    return this.Entities.Where(where).OrderBy(orderBy);
            }
        }

        public override IQueryable<T> GetList<TOrderBy>(Expression<Func<T, TOrderBy>> orderBy, int pageindex, int pagesize, out int totalRecords, SortOrder sortOrder = SortOrder.Descending)
        {
            return GetList(null, orderBy, pageindex, pagesize, out totalRecords, sortOrder);
        }

        public override IQueryable<T> GetList<TOrderBy>(Expression<Func<T, bool>> @where, Expression<Func<T, TOrderBy>> orderBy, int pageindex, int pagesize, out int totalRecords, SortOrder sortOrder = SortOrder.Descending)
        {
            if (pageindex < 1)
                throw new ArgumentException("pageindex");
            if (pagesize < 1)
                throw new ArgumentException("pagesize");

            int skip = (pageindex - 1) * pagesize;
            var _query = this.Entities.AsQueryable().AsNoTracking();
            if (null != where)
                _query = _query.Where(where);

            totalRecords = _query.Count();
            if (sortOrder == SortOrder.Descending)
            {
                _query = _query.OrderByDescending(orderBy);
            }
            else
                _query = _query.OrderBy(orderBy);
            return _query.Skip(skip).Take(pagesize);
        }

        public override IQueryable<T> GetList<TOrderBy>(Expression<Func<T, bool>> @where, Expression<Func<T, TOrderBy>> orderBy, Pager pg, SortOrder sortOrder = SortOrder.Descending)
        {
            int totalRecords;
            var list = GetList(where, orderBy, pg.page, pg.rows, out totalRecords, sortOrder);
            pg.totalRows = totalRecords;
            return list;
        }

        public override int Add(T entity)
        {
            try
            {
                if (entity == null)
                    throw new ArgumentNullException();

                this.Entities.Add(entity);

                return this._context.SaveChanges();
            }
            catch (Exception dbEx)
            {
                throw dbEx;
            }
        }

        public override void AddList(IEnumerable<T> entities)
        {
            try
            {
                if (entities == null)
                    throw new ArgumentNullException();

                foreach (var entity in entities)
                    this.Entities.Add(entity);

                this._context.SaveChanges();
            }
            catch (Exception dbEx)
            {
                throw dbEx;
            }
        }

        public override bool Update(T entity)
        {
            try
            {
                if (entity == null)
                    throw new ArgumentNullException();

                return this._context.SaveChanges() > 0;
            }
            catch (Exception dbEx)
            {
                throw dbEx;
            }
        }

        public override void Update(IEnumerable<T> entities)
        {
            try
            {
                if (entities == null)
                    throw new ArgumentNullException();

                this._context.SaveChanges();
            }
            catch (Exception dbEx)
            {
                throw dbEx;
            }
        }

        public override void Delete(T entity)
        {
            try
            {
                if (entity == null)
                    throw new ArgumentNullException();

                this.Entities.Remove(entity);

                this._context.SaveChanges();
            }
            catch (Exception dbEx)
            {
                throw dbEx;
            }
        }

        public override void Delete(IEnumerable<T> entities)
        {
            try
            {
                if (entities == null)
                    throw new ArgumentNullException();

                foreach (var entity in entities)
                    this.Entities.Remove(entity);

                this._context.SaveChanges();
            }
            catch (Exception dbEx)
            {
                throw dbEx;
            }
        }

        public override IQueryable<T> Table
        {
            get
            {
                return this.Entities;
            }
        }

        
        //protected string GetFullErrorText(Exception exc)
        //{
        //    var msg = string.Empty;
        //    foreach (var validationErrors in exc.EntityValidationErrors)
        //        foreach (var error in validationErrors.ValidationErrors)
        //            msg += string.Format("Property: {0} Error: {1}", error.PropertyName, error.ErrorMessage) + Environment.NewLine;
        //    return msg;
        //}
    }
}