ECommerce/ECommerce.Core/Services/CategoryService.cs

using System;
using Commerce.Contracts.DTOs;
using Commerce.Domain;
using Commerce.Domain.Entities;
using Generic.Contracts.Generics;
using Generic.Services;
using Microsoft.EntityFrameworkCore;

namespace Commerce.Core.Services;

public class CategoryService
{

    private readonly Context context;

    public CategoryService(Context context)
    {
        this.context = context;
    }



    public async Task CreateCategory(CategoryVM categoryVM)
    {
        var category = Category.ToEntity(categoryVM);
        await context.Categories.AddAsync(category);
        await context.SaveChangesAsync();
    }


    public async Task UpdateCategory(CategoryVM categoryVM)
    {
        if (categoryVM.Id == null) throw new ArgumentException("Category ID is required for update.");

        var existingCategory = await context.Categories
            .FirstOrDefaultAsync(x => x.Id == categoryVM.Id);

        if (existingCategory == null) throw new KeyNotFoundException("Category not found.");

        // Update properties
        existingCategory.Translations = categoryVM.Translations?.Select(t => new CategoryTranslation
        {
            Language = t.Language,
            Info = new CategoryInfo
            {
                Name = t.Info.Name,
                Description = t.Info.Description,
                TechnicalDetails = t.Info.TechnicalDetails?.Select(td => new Commerce.Domain.Entities.TechnicalDetail { Key = td.Key, Value = td.Value }).ToList() ?? new()
            }
        }).ToList() ?? new();

        existingCategory.Photos = categoryVM.Photos ?? Array.Empty<string>();
        existingCategory.ParentCategoryId = categoryVM.ParentCategoryId;
        existingCategory.IsBundle = categoryVM.IsBundle;

        await context.SaveChangesAsync();
    }


    public async Task RemoveCategory(Guid id)
    {
        var category = await context.Categories.FindAsync(id);
        if (category != null) context.Categories.Remove(category);
        await context.SaveChangesAsync();
    }



    public async Task<CategoryVM> GetCategory(Guid id)
    {
        var category = await context.Categories.FindAsync(id);
        return category != null ? Category.ToVM(category) : new CategoryVM();
    }



    public async Task<(List<CategoryVM>, int)> FetchCategory(
        CategoryFilter categoryFilter,
        Pagination pagination
        )
    {
        var query = context.Categories.AsQueryable();
        query = query.ApplyAdvancedFilter(categoryFilter);
        // query = query.ApplySorting(sortBy);
        if (categoryFilter.Random ?? false)
        {
            query = query.OrderBy(x => Guid.NewGuid());
        }
        else
        {
            // query = query.ApplySorting(sortBy);
        }
        var count = query.Count();
        query = query.Paginate(pagination);

        var lang = categoryFilter.Language;
        return (await query.Select(x => Category.ToVM(x, lang)).ToListAsync(), count);
    }



    public async Task<List<Category>> GetAllCategories(string name = "")
    {

        var categories = await context.Categories.ToListAsync();
        if (!string.IsNullOrEmpty(name))
            categories = categories.Where(x => x.Translations.Any(t => t.Info.Name.Contains(name, StringComparison.OrdinalIgnoreCase))).ToList();
        return categories;

    }


    public async Task<List<Category>> GetAllCategories_Tree(string name = "")
    {

        var cate = await context.Categories
                            .ToListAsync();


        if (!string.IsNullOrEmpty(name))
        {
            cate = cate.Where(x => x.Translations.Any(t => t.Info.Name.Contains(name, StringComparison.OrdinalIgnoreCase))).ToList();
        }

        var lista = cate.Where(x => x.ParentCategoryId == null).ToList();
        Console.WriteLine($"{lista.Count}");


        foreach (var cat in lista)
        {
            cat.ChildCategories = NewMethod(cate, cat.Id);
        }

        Console.WriteLine($"{lista.Count}");

        return lista;



        // if (!string.IsNullOrEmpty(name))
        //     categories = categories.Where(x => x.Name.Contains(name));

        // var lista = await categories.ToListAsync();
        // return lista;

    }

    private static List<Category> NewMethod(List<Category> categories, Guid parent)
    {
        var toreturn = new List<Category>();

        var children = categories.Where(x => x.ParentCategoryId == parent).ToList();

        foreach (var item in children)
        {
            item.ChildCategories = NewMethod(categories, item.Id);
        }

        return children;
    }

    public async Task<List<Category>> GetChildCategories(Guid categoryId)
    {
        var categories = new List<Category>();

        categories = await context.Categories.Where(x => x.ParentCategoryId == categoryId).ToListAsync();

        if (categories.Count != 0)
        {
            foreach (var category in categories)
            {
                categories.AddRange(await GetChildCategories(categoryId));
            }
        }

        return categories;
    }

    public async Task<List<Category>> GetChildrenList(Guid categoryId)
    {
        return await context.Categories.Where(x => x.Id == categoryId)
           .Include(x => x.ChildCategories)
           .SelectMany(x => x.ChildCategories)
           .ToListAsync();


    }


    // public async Task<List<Category>> GetRandomCategories(int categoriesNeeded, int productsNeeded)
    // {
    //     var count = await context.Categories.CountAsync();
    //     var categories = new List<Category>();
    //     var random = new Random();
    //     var randoms = new List<int>();
    //     for (int i = 0; i < categoriesNeeded; i++)
    //     {
    //         var newRandom = random.Next(count);
    //         if (!randoms.Contains(newRandom))
    //         {
    //             randoms.Add(newRandom);
    //             categories.Add(await context.Categories
    //                 .Skip(random.Next(count))
    //                 .Take(1)
    //                 .Include(x => x.Products)
    //                 .FirstOrDefaultAsync()
    //             );
    //         }
    //     }

    //     return categories;

    // }

    // public async Task<Category> GetCategoryAsync(int id)
    // {
    //     return await context.Categories.FirstOrDefaultAsync(c => c.Id == id);
    // }

    // public async Task<List<Category>> GetCategoriesPaginated(Pagination pagination)
    // {
    //     var query = context.Categories.AsQueryable();
    //     query = query.Skip((pagination.CurrentPage - 1) * pagination.PageSize)
    //         .Take(pagination.PageSize);
    //     return await query.ToListAsync();
    // }

    // public async Task<List<CategoryVM>> GetRandomCategories(int count = 4)
    // {
    //     return await context
    //         .Categorys.OrderBy(x => Guid.NewGuid())
    //         .Take(count)
    //         .Select(x => Category.ToVM(x))
    //         .ToListAsync();
    // }
}