using System;
using System.Collections.Generic;
using System.Linq;
using AvaloniaApplication4.AdditionalModels;
using AvaloniaApplication4.Models;
using AvaloniaApplication4.Views.ActionPages;
using Microsoft.EntityFrameworkCore;
using ReactiveUI;

namespace AvaloniaApplication4.ViewModels
{
	public class EditAndAddModuleViewModel : ViewModelBase
	{
        GlobalsData globalsData;
        User? user;
        Module module;

        bool isNotNew = false;

        List<BindingMdkWithModels> mdkWithModulesBinding = new List<BindingMdkWithModels>();


        public bool IsNotNew { get => isNotNew; set => isNotNew = value; }
        public Module Module { get => module; set => module = value; }
        public List<BindingMdkWithModels> MdkWithModulesBinding
        {
            get { return mdkWithModulesBinding; }
            set
            {
                mdkWithModulesBinding = value;
                OnPropertyChanged("MdkWithModulesBinding");
            }
        }

        public EditAndAddModuleViewModel(GlobalsData globalsData, User? user)
        {
            this.globalsData = globalsData;
            this.user = user;
            module = new Module();
        }

        public EditAndAddModuleViewModel(GlobalsData globalsData, User? user, Module module) : this(globalsData, user)
        {
            this.module = module;
            isNotNew = true;
            var all = dataBase.MdkWithModules
                .Include(x => x.IdMdkNavigation)
                .Include(x => x.IdModuleNavigation)
                .Where(x => x.IdModule == module.IdModule)
                .ToList();
            foreach (var obj in all)
            {
                var currentSubject = dataBase.Subjects.FirstOrDefault(x => x.IdSubject == obj.IdMdk);
                if (currentSubject != null)
                {
                    mdkWithModulesBinding.Add(new BindingMdkWithModels(currentSubject));
                }
            }
        }
        public void DeleteCurrentSubject(int idSubject)
        {
            var temp = MdkWithModulesBinding;
            var currentSubject = temp.FirstOrDefault(x => x.Id == idSubject);
            if (currentSubject != null)
            {
                temp.Remove(currentSubject);
            }
            MdkWithModulesBinding = temp;
        }
        public void AddNewSubject()
        {
            var temp = MdkWithModulesBinding;
            temp.Add(new BindingMdkWithModels());
            MdkWithModulesBinding = temp;
        }

        public void Save()
        {
            if (Module.CodeModule != string.Empty && Module.Name != string.Empty)
            {
                if (!isNotNew)
                {
                    dataBase.Modules.Add(Module);

                    //тут надо внести в базу все предметы которые относятся к модулю, исключая при этом повторяющиеся элементы


                }
                else
                {
                    var obj = dataBase.Modules.FirstOrDefault(x => x.IdModule == Module.IdModule);
                    if (obj != null)
                    {
                        obj.Name = Module.Name;
                        obj.CodeModule = Module.CodeModule;
                        //тут тоже самое, но немного сложнее, надо проанализировать уже имеющиеся записи и добавить только новые также исключая повторение
                        DeleteDuplicates();
                        var allItems = dataBase.MdkWithModules.Where(x => x.IdModule == obj.IdModule).ToList();
                        foreach (var item in allItems)
                        {
                            dataBase.MdkWithModules.Remove(item);
                        }
                        dataBase.SaveChanges();
                        foreach (var item in MdkWithModulesBinding)
                        {
                            var newObj = new MdkWithModule() { IdMdk = item.Id, IdModule = obj.IdModule };
                            dataBase.MdkWithModules.Add(newObj);
                        }
                        dataBase.SaveChanges();
                    }
                }
                dataBase.SaveChanges();
            }
        }
        public void Delete() 
        {
            if (isNotNew)
            {
                var obj = dataBase.Modules.FirstOrDefault(x => x.IdModule == Module.IdModule);
                if (obj != null)
                {
                    dataBase.Modules.Remove(obj);
                    dataBase.SaveChanges();
                    GoBack();
                }
            }
        }
        /// <summary>
        /// Исключение повторяющихся записей в списке предметов
        /// </summary>
        private void DeleteDuplicates()
        {
            for (int i = 1; i < MdkWithModulesBinding.Count; i++)
            {
                if (MdkWithModulesBinding[i-1].Id == MdkWithModulesBinding[i].Id)
                {
                    MdkWithModulesBinding.Remove(MdkWithModulesBinding[i]);
                }
            }
        }
        public void GoBack()
        {
            globalsData.GlobalUserControl = new AllSubjectsModulesAndProgramTemplates(user, ref globalsData);
        }

        public class BindingMdkWithModels: ViewModelBase
        {
            List<Subject> allMDK;
            Subject currentMDK;
            int id;

            public BindingMdkWithModels()
            {
                allMDK = dataBase.Subjects
                    .Include(x=>x.IdCodeAcademicSubjectNavigation)
                    .Where(x=>x.IdCodeAcademicSubjectNavigation.IdCodeAcademicSubjects == "МДК")
                    .ToList();
                currentMDK = allMDK.First();
                id = currentMDK.IdSubject;
            }

            public BindingMdkWithModels(Subject currentMDK) : this()
            {
                this.currentMDK = allMDK.FirstOrDefault(x=>x.IdSubject == currentMDK.IdSubject);
                id = this.currentMDK.IdSubject;
            }

            public List<Subject> AllMDK { get => allMDK; set => allMDK = value; }
            public Subject CurrentMDK { get => currentMDK; set => currentMDK = value; }
            public int Id { get => id; set => id = value; }
        }
    }
}