MoneyMap/MoneyMap/Pages/CategoryMappings.cshtml.cs

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using MoneyMap.Services;

namespace MoneyMap.Pages
{
    public class CategoryMappingsModel : PageModel
    {
        private readonly ITransactionCategorizer _categorizer;

        public CategoryMappingsModel(ITransactionCategorizer categorizer)
        {
            _categorizer = categorizer;
        }

        public List<CategoryGroup> CategoryGroups { get; set; } = new();
        public int TotalMappings { get; set; }
        public int TotalCategories { get; set; }

        [TempData]
        public string? SuccessMessage { get; set; }

        public async Task OnGetAsync()
        {
            var mappings = await _categorizer.GetAllMappingsAsync();

            CategoryGroups = mappings
                .GroupBy(m => m.Category)
                .Select(g => new CategoryGroup
                {
                    Category = g.Key,
                    Patterns = g.Select(m => m.Pattern).ToList(),
                    Count = g.Count()
                })
                .OrderBy(g => g.Category)
                .ToList();

            TotalMappings = mappings.Count;
            TotalCategories = CategoryGroups.Count;
        }

        public async Task<IActionResult> OnPostSeedDefaultsAsync()
        {
            await _categorizer.SeedDefaultMappingsAsync();
            SuccessMessage = "Default category mappings loaded successfully!";
            return RedirectToPage();
        }

        public class CategoryGroup
        {
            public required string Category { get; set; }
            public required List<string> Patterns { get; set; }
            public int Count { get; set; }
        }
    }
}