using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Web;
using Weee.DAL;
using Weee.Models;

namespace Weee.Service
{
    public class PowerConsumptionDataService : WeeeLCADataService
    {
        public PowerConsumptionDataService(WeeeDataContext db)
        : base(db)
        {
        }

        public IQueryable<LCARiskAssmtSurveyForm_PowerConsumption> GetList(int LCAID)
        {
            if (!AuthorizedLCAs.Contains(LCAID)) throw new Exception("not authorized");
            return _db.Set<LCARiskAssmtSurveyForm_PowerConsumption>().Where(x => x.LCAID == LCAID)
                .OrderByDescending(x => x.ID);
        }

        public LCARiskAssmtSurveyForm_PowerConsumption Save(LCARiskAssmtSurveyForm_PowerConsumption toBeSave)
        {
            var user = GetUserContext();

            CheckScenario(toBeSave);

            if (!AuthorizedLCAs.Contains(toBeSave.LCAID)) throw new Exception("not authorized");

            var typeModels = _db.Set<LCARiskAssmtSurveyForm_PowerConsumption>().AsNoTracking().Where(x => x.LCAID == toBeSave.LCAID && x.ModelType == toBeSave.ModelType).ToList();

            var entry = _db.Entry(toBeSave);
            if (toBeSave.ID == 0)
            {
                toBeSave.CreatedBy = user.Id;
                toBeSave.CreatedDate = DateTime.Now;
                entry.State = EntityState.Added;

                typeModels.Add(toBeSave);
            }
            else
            {
                toBeSave.ModifiedBy = user.Id;
                toBeSave.ModifiedDate = DateTime.Now;
                entry.State = EntityState.Modified;
                entry.Property(x => x.LCAID).IsModified = false;
            }

            if (typeModels.Count(x => IsStandbyPower(x)) == 1)
            {
                var standbyPower = typeModels.First(x => IsStandbyPower(x));

                if (standbyPower.ID != toBeSave.ID)
                {
                    var sumWorkingHour = typeModels.Where(x => IsNotStandbyPower(x)).Sum(x => x.WorkingHour);

                    standbyPower.WorkingHour = 8760 - sumWorkingHour;
                    _db.Entry(standbyPower).State = EntityState.Modified;
                }
            }

            _db.SaveChanges();
            return toBeSave;
        }

        private bool IsStandbyPower(LCARiskAssmtSurveyForm_PowerConsumption powerConsumption)
        {
            return powerConsumption.Scenario.Contains("待機") || powerConsumption.Scenario.Contains("關機");
        }

        private bool IsNotStandbyPower(LCARiskAssmtSurveyForm_PowerConsumption powerConsumption)
        {
            return !IsStandbyPower(powerConsumption);
        }

        private void CheckScenario(LCARiskAssmtSurveyForm_PowerConsumption toBeSave)
        {
            if (_db.Set<LCARiskAssmtSurveyForm_PowerConsumption>().Any(i => i.LCAID == toBeSave.LCAID && i.ModelType == toBeSave.ModelType && i.Scenario == toBeSave.Scenario && (toBeSave.ID == 0 || toBeSave.ID != i.ID)))
            {
                throw new Exception($"同機種型號的使用场景不得重複：{nameof(toBeSave.Scenario)}");
            }
        }

        public void Delete(int ID)
        {
            var entry = _db.Set<LCARiskAssmtSurveyForm_PowerConsumption>().Where(x => x.ID == ID).Single();
            var LCA = GetLCA(entry.LCAID);
            if (LCA.Status != LCAStatus.New && LCA.Status != LCAStatus.Processing) throw new Exception("Business logic error , should not delete data in this status: " + LCA.Status.ToString());

            var typeModels = _db.Set<LCARiskAssmtSurveyForm_PowerConsumption>()
                .AsNoTracking()
                .Where(x => x.LCAID == entry.LCAID && x.ModelType == entry.ModelType && x.ID != ID)
                .ToList();

            if (typeModels.Count(x => IsStandbyPower(x)) == 1)
            {
                var standbyPower = typeModels.First(x => IsStandbyPower(x));
                var sumWorkingHour = typeModels.Where(x => IsNotStandbyPower(x)).Sum(x => x.WorkingHour);

                standbyPower.WorkingHour = 8760 - sumWorkingHour;
                _db.Entry(standbyPower).State = EntityState.Modified;
            }

            var ToBeDelete = _db.Entry(entry);
            ToBeDelete.State = EntityState.Deleted;

            _db.SaveChanges();
        }
    }
}