DocumentOrganizer/Diligent.WebAPI.Business/Services/CategoryService.cs

using Dapper;
using Diligent.WebAPI.Contracts.DTOs.Categories;
using Microsoft.Extensions.Configuration;
using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Diligent.WebAPI.Business.Services
{
    public class CategoryService : ICategoryService
    {
        private readonly DatabaseContext _context;
        private readonly IMapper _mapper;
        private readonly UserManager<User> _userManager;
        private readonly IConfiguration _configuration;

        public CategoryService(DatabaseContext context, IMapper mapper, UserManager<User> userManager, IConfiguration configuration)
        {
            _context = context;
            _mapper = mapper;
            _userManager = userManager;
            _configuration = configuration;
        }

        public async Task<CategoriesParentChild> GetRootCategories(int userId,int parentCategoryId)
        {
            var user = await _userManager.FindByIdAsync(userId.ToString());
            var role = (await _userManager.GetRolesAsync(user))[0];

            if (role == "SuperAdmin")
                if (parentCategoryId == -1)
                {
                    return new CategoriesParentChild
                    {
                        Categories = _mapper.Map<List<CategoriesNamesResponse>>
                        (await _context.Categories.Where(k => k.ParentCategory == null).ToListAsync()),
                        ChildParentRelations = await GetByParentChild(parentCategoryId)
                    };
                }
                else
                {
                    return new CategoriesParentChild
                    {
                        Categories = await GetChildCategories(parentCategoryId, userId, role),
                        ChildParentRelations = await GetByParentChild(parentCategoryId)
                    };
                }

            var userCategories = new List<UserCategories>();

            if(parentCategoryId == -1)
                userCategories = await _context.UserCategories
               .Where(k => k.UserId == userId && k.Category.ParentCategory == null)
               .Include(t => t.Category)
               .ToListAsync();
            else
                return new CategoriesParentChild
                {
                    Categories = await GetChildCategories(parentCategoryId, userId, role),
                    ChildParentRelations = await GetByParentChild(parentCategoryId)
                };

            return new CategoriesParentChild
            {
                Categories = GetCategoriesFromUserCategories(userCategories),
                ChildParentRelations = await GetByParentChild(parentCategoryId)
            };
        }
        public async Task<Category> GetCategoryEntityById(int? id) =>
            await _context.Categories.Where(x => x.Id == id).FirstOrDefaultAsync();

        public async Task<List<IsGrantedCategory>> GetCategories(int userId)
        {
            var grantedCategories = await _context.UserCategories.Where(k => k.UserId == userId).ToListAsync();
            var allCategories = await _context.Categories.ToListAsync();
            var result = new List<IsGrantedCategory>();
            for (int i = 0; i < allCategories.Count; i++)
            {
                var newCategory = new IsGrantedCategory
                {
                    Id = allCategories[i].Id,
                    Name = allCategories[i].Name,
                };
                bool isGranted = false;
                for (int j = 0; j < grantedCategories.Count; j++)
                {
                    if(grantedCategories[j].CategoryId == allCategories[i].Id && userId == grantedCategories[j].UserId)
                    {
                        isGranted = true;
                        break;
                    }
                }
                newCategory.IsChecked = isGranted;
                result.Add(newCategory);
                isGranted = false;
            }

            return result;
        }
        private List<CategoriesNamesResponse> GetCategoriesFromUserCategories(List<UserCategories> userCategories)
        {
            var res = new List<CategoriesNamesResponse>();

            for (int i = 0; i < userCategories.Count; i++)
            {
                res.Add(_mapper.Map<CategoriesNamesResponse>(userCategories[i].Category));
            }

            return res;
        }
        private async Task<List<CategoriesNamesResponse>> GetChildCategories(int parentCategoryId, int userId, string role)
        {
            if (role == "SuperAdmin")
                return _mapper.Map<List<CategoriesNamesResponse>>(
                    await _context.Categories
                    .Where(k => k.ParentCategory != null && k.ParentCategory.Id == parentCategoryId)
                    .ToListAsync());

            var userCategories = await _context.UserCategories
                .Where(k => k.UserId == userId && k.Category != null && k.Category.ParentCategory != null && k.Category.ParentCategory.Id == parentCategoryId)
                .Include(t => t.Category)
                .ToListAsync();

            return GetCategoriesFromUserCategories(userCategories);
        }

        private async Task<List<CategoriesNamesResponse>> GetByParentChild(int categoryId)
        {
            var categories = await _context.Categories.Include(x => x.ParentCategory).ToListAsync();
            var categoryById = categories.Where(x => x.Id == categoryId).FirstOrDefault();

            List<CategoriesNamesResponse> dto = new();
            while (true)
            {
                if (categoryById == null) break;
                dto.Add(new CategoriesNamesResponse
                {
                    Id = categoryById.Id,
                    Name = categoryById.Name
                });
                categoryById = categoryById.ParentCategory;
            }

            dto.Reverse();

            return dto;
        }
    }
}