RecipeRepository.cs

using RecipeSharing.Domain.Entities;

namespace RecipeSharing.Infrastructure.Persistence;

/// <summary>
/// Interface for recipe repository operations.
/// </summary>
public interface IRecipeRepository
{
    /// <summary>
    /// Gets all recipes from the repository.
    /// </summary>
    Task<IEnumerable<Recipe>> GetAllAsync();

    /// <summary>
    /// Gets a specific recipe by identifier.
    /// </summary>
    Task<Recipe?> GetByIdAsync(int id);

    /// <summary>
    /// Adds a new recipe to the repository.
    /// </summary>
    Task<Recipe> AddAsync(Recipe recipe);

    /// <summary>
    /// Updates an existing recipe in the repository.
    /// </summary>
    Task<Recipe> UpdateAsync(Recipe recipe);

    /// <summary>
    /// Deletes a recipe from the repository.
    /// </summary>
    Task DeleteAsync(int id);

    /// <summary>
    /// Saves all pending changes.
    /// </summary>
    Task SaveChangesAsync();
}

/// <summary>
/// In-memory implementation of the recipe repository.
/// This is a placeholder for future database implementations.
/// </summary>
public sealed class InMemoryRecipeRepository : IRecipeRepository
{
    private readonly Dictionary<int, Recipe> _recipes = [];
    private int _nextId = 1;

    public Task<IEnumerable<Recipe>> GetAllAsync()
    {
        return Task.FromResult(_recipes.Values.AsEnumerable());
    }

    public Task<Recipe?> GetByIdAsync(int id)
    {
        _recipes.TryGetValue(id, out var recipe);
        return Task.FromResult(recipe);
    }

    public Task<Recipe> AddAsync(Recipe recipe)
    {
        recipe.Id = _nextId++;
        _recipes[recipe.Id] = recipe;
        return Task.FromResult(recipe);
    }

    public Task<Recipe> UpdateAsync(Recipe recipe)
    {
        if (!_recipes.ContainsKey(recipe.Id))
        {
            throw new InvalidOperationException($"Recipe with ID {recipe.Id} not found.");
        }

        _recipes[recipe.Id] = recipe;
        return Task.FromResult(recipe);
    }

    public Task DeleteAsync(int id)
    {
        if (!_recipes.Remove(id))
        {
            throw new InvalidOperationException($"Recipe with ID {id} not found.");
        }

        return Task.CompletedTask;
    }

    public Task SaveChangesAsync()
    {
        return Task.CompletedTask;
    }
}