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

namespace PalGain.Core
{
    /// <summary>
    /// Entity Framework repository
    /// </summary>
    public partial class EfRepository<T> : IRespository<T> where T : BaseEntity
    {
        #region Fields

        private readonly IDbContext _context;
        private IDbSet<T> _entities;

        #endregion

        #region Ctor

        /// <summary>
        /// Ctor
        /// </summary>
        /// <param name="context">Object context</param>
        public EfRepository(IDbContext context)
        {
            this._context = context;
        }

        #endregion

        #region Methods

        /// <summary>
        /// Get entity by identifier
        /// </summary>
        /// <param name="id">Identifier</param>
        /// <returns>Entity</returns>
        public virtual T GetById(object id)
        {
            //see some suggested performance optimization (not tested)
            //http://stackoverflow.com/questions/11686225/dbset-find-method-ridiculously-slow-compared-to-singleordefault-on-id/11688189#comment34876113_11688189
            return this.Entities.Find(id);
        }
        /// <summary>
        /// Ö´ÐÐSQLÓï¾ä
        /// </summary>
        /// <returns></returns>
        public virtual int ExecuteSqlCommand(string sql)
        {
            return this._context.ExecuteSqlCommand(sql);
        }

        /// <summary>
        /// Insert entity
        /// </summary>
        /// <param name="entity">Entity</param>
        public virtual void Insert(T entity)
        {
            try
            {
                if (entity == null)
                    throw new ArgumentNullException("entity");

                this.Entities.Add(entity);

                this._context.SaveChanges();
            }
            catch (DbEntityValidationException dbEx)
            {
                var msg = string.Empty;

                foreach (var validationErrors in dbEx.EntityValidationErrors)
                    foreach (var validationError in validationErrors.ValidationErrors)
                        msg += string.Format("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage) + Environment.NewLine;

                var fail = new Exception(msg, dbEx);
                throw fail;
            }
        }

        /// <summary>
        /// Insert entities
        /// </summary>
        /// <param name="entities">Entities</param>
        public virtual void Insert(IEnumerable<T> entities)
        {
            try
            {
                if (entities == null)
                    throw new ArgumentNullException("entities");

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

                this._context.SaveChanges();
            }
            catch (DbEntityValidationException dbEx)
            {
                var msg = string.Empty;

                foreach (var validationErrors in dbEx.EntityValidationErrors)
                    foreach (var validationError in validationErrors.ValidationErrors)
                        msg += string.Format("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage) + Environment.NewLine;

                var fail = new Exception(msg, dbEx);
                throw fail;
            }
        }

        /// <summary>
        /// Update entity
        /// </summary>
        /// <param name="entity">Entity</param>
        public virtual void Update(T entity)
        {
            try
            {
                if (entity == null)
                    throw new ArgumentNullException("entity");

                int ret = this._context.SaveChanges();
                BatchService.Framework.Utility.LogHelper.Info("¸üвÙ×÷Ö´Ðнá¹û:" + ret + ",Id:" + entity.Id);
            }
            catch (DbEntityValidationException dbEx)
            {
                var msg = string.Empty;

                foreach (var validationErrors in dbEx.EntityValidationErrors)
                    foreach (var validationError in validationErrors.ValidationErrors)
                        msg += Environment.NewLine + string.Format("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage);

                var fail = new Exception(msg, dbEx);
                throw fail;
            }
        }

        /// <summary>
        /// Update entities
        /// </summary>
        /// <param name="entities">Entities</param>
        public virtual void Update(IEnumerable<T> entities)
        {
            try
            {
                if (entities == null)
                    throw new ArgumentNullException("entities");

                this._context.SaveChanges();
            }
            catch (DbEntityValidationException dbEx)
            {
                var msg = string.Empty;

                foreach (var validationErrors in dbEx.EntityValidationErrors)
                    foreach (var validationError in validationErrors.ValidationErrors)
                        msg += string.Format("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage) + Environment.NewLine;

                var fail = new Exception(msg, dbEx);
                throw fail;
            }
        }

        /// <summary>
        /// Delete entity
        /// </summary>
        /// <param name="entity">Entity</param>
        public virtual void Delete(T entity)
        {
            try
            {
                if (entity == null)
                    throw new ArgumentNullException("entity");

                this.Entities.Remove(entity);

                this._context.SaveChanges();
            }
            catch (DbEntityValidationException dbEx)
            {
                var msg = string.Empty;

                foreach (var validationErrors in dbEx.EntityValidationErrors)
                    foreach (var validationError in validationErrors.ValidationErrors)
                        msg += Environment.NewLine + string.Format("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage);

                var fail = new Exception(msg, dbEx);
                throw fail;
            }
        }

        /// <summary>
        /// Delete entities
        /// </summary>
        /// <param name="entities">Entities</param>
        public virtual void Delete(IEnumerable<T> entities)
        {
            try
            {
                if (entities == null)
                    throw new ArgumentNullException("entities");

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

                this._context.SaveChanges();
            }
            catch (DbEntityValidationException dbEx)
            {
                var msg = string.Empty;

                foreach (var validationErrors in dbEx.EntityValidationErrors)
                    foreach (var validationError in validationErrors.ValidationErrors)
                        msg += Environment.NewLine + string.Format("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage);

                var fail = new Exception(msg, dbEx);
                throw fail;
            }
        }

        #endregion

        #region Properties

        /// <summary>
        /// Gets a table
        /// </summary>
        public virtual IQueryable<T> Table
        {
            get
            {

                return this.Entities;
            }
        }

        /// <summary>
        /// Gets a table with "no tracking" enabled (EF feature) Use it only when you load record(s) only for read-only operations
        /// </summary>
        public virtual IQueryable<T> TableNoTracking
        {
            get
            {
                return this.Entities.AsNoTracking();
            }
        }

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

        #endregion
    }
}