using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Web;
using EnVisage.Models;

namespace EnVisage.Code.BLL
{
    public class CompanyManager : ManagerBase<Company, CompanyModel>
    {
        public CompanyManager(EnVisageEntities dbContext)
            : base(dbContext)
        {
        }
        protected override Company InitInstance()
        {
            return new Company { Id = Guid.NewGuid() };
        }

        protected override Company RetrieveReadOnlyById(Guid key)
        {
            return DataTable.AsNoTracking().FirstOrDefault(t => t.Id == key);
        }

        public override DbSet<Company> DataTable
        {
            get
            {
                return DbContext.Companies;
            }
        }

        #region Public Methods
        /// <summary>
        /// Loads a first Company with parentId == null.
        /// </summary>
        /// <param name="isReadOnly">Indicates that object will not be saved later in the code. Use <b>false</b> if you need to save an updated object.</param>
        /// <returns>A <see cref="Company"/> object.</returns>
        public Company LoadParent(bool isReadOnly = true)
        {
            var parent = DbContext.Companies.AsNoTracking().FirstOrDefault(t => t.ParentCompanyId == null);
            if (parent == null)
                throw new BLLException("There is no Parent Company in the database. It should be created on application start.", false);
            return parent;
        }

        public CompanyModel LoadWithChildCollections(Guid? value, bool isReadOnly = true)
        {
            CompanyModel result = (CompanyModel)base.Load(value, isReadOnly);
            if (value.HasValue)
            {
                var clients = DbContext.Company2Client.Where(x => x.CompanyId == value.Value).ToList();
                result.ClientId = clients.Select(x => x.ClientId).ToList();
                result.Client = clients.Select(x => x.Client.Name).ToList();

                var company2Views = DbContext.Company2View.Where(x => x.CompanyId == value.Value).ToList();
                result.ViewId = company2Views.Select(x => x.ViewId.Value).ToList();
                result.ViewName = company2Views.Select(x => x.View.Name).ToList();
            }
            return result;
        }

        public override Company Save(CompanyModel model)
        {
            Company company = null;
            if (Guid.Empty.Equals(model.Id))
            {
                company = base.Save(model);

                if (model.ClientId != null)
                {
                    foreach (var clientId in model.ClientId)
                    {
                        var client = DbContext.Company2Client.Create();
                        client.Id = Guid.NewGuid();
                        client.ClientId = clientId;
                        client.CompanyId = company.Id;
                        DbContext.Company2Client.Add(client);
                    }
                }

                if (model.ViewId != null)
                {
                    foreach (var viewId in model.ViewId)
                    {
                        var company2View = DbContext.Company2View.Create();
                        company2View.Id = Guid.NewGuid();
                        company2View.ViewId = viewId;
                        company2View.CompanyId = company.Id;
                        DbContext.Company2View.Add(company2View);
                    }
                }
            }
            else
            {
                company = base.Save(model);

                var clients = DbContext.Company2Client.Where(x => x.CompanyId == model.Id).ToList();
                clients.Where(x => model.ClientId == null || !model.ClientId.Contains(x.ClientId)).ToList().
                    ForEach(x => DbContext.Entry(x).State = EntityState.Deleted);

                var company2Views = DbContext.Company2View.Where(x => x.CompanyId == model.Id).ToList();
                company2Views.Where(x => model.ViewId == null || !model.ViewId.Contains(x.ViewId.Value)).ToList().
                    ForEach(x => DbContext.Entry(x).State = EntityState.Deleted);

                if (model.ClientId != null)
                {
                    foreach (var clientId in model.ClientId.Where(c => !clients.Select(x => x.ClientId).Contains(c)))
                    {
                        var client = DbContext.Company2Client.Create();
                        client.Id = Guid.NewGuid();
                        client.ClientId = clientId;
                        client.CompanyId = company.Id;
                        DbContext.Company2Client.Add(client);
                    }
                }

                if (model.ViewId != null)
                {
                    foreach (var viewId in model.ViewId.Where(c => !company2Views.Select(x => x.ViewId).Contains(c)))
                    {
                        var company2View = DbContext.Company2View.Create();
                        company2View.Id = Guid.NewGuid();
                        company2View.ViewId = viewId;
                        company2View.CompanyId = model.Id;
                        DbContext.Company2View.Add(company2View);
                    }
                }
            }
            return company;
        }
        #endregion
    }
}