EnvelopeGenerator/EnvelopeGenerator.Infrastructure/DependencyExtensions.cs

using EnvelopeGenerator.Application.Contracts.Repositories;
using EnvelopeGenerator.Infrastructure.Repositories;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.EntityFrameworkCore;
using DigitalData.Core.Infrastructure;
using EnvelopeGenerator.Domain.Entities;
using DigitalData.Core.Infrastructure.AutoMapper;
using EnvelopeGenerator.Application.Contracts.SQLExecutor;

namespace EnvelopeGenerator.Infrastructure;

public static class DIExtensions
{
    /// <summary>
    /// Registers the required repositories for the Envelope Generator service to the given <see cref="IServiceCollection"/>.
    /// This method adds the repositories for various envelope-related entities, such as configuration, document receivers, envelopes, and users,
    /// as scoped services to the dependency injection container. Optionally, it can also configure the <see cref="EGDbContext"/> 
    /// with the provided database context options if specified.
    /// </summary>
    /// <param name="services">The <see cref="IServiceCollection"/> to which the services are added.</param>
    /// <param name="dbContextOptions">An optional action to configure the <see cref="DbContextOptionsBuilder"/> for the <see cref="EGDbContext"/>. 
    /// If not provided, the <see cref="EGDbContext"/> will not be configured.</param>
    /// <returns>The updated <see cref="IServiceCollection"/> with the added repository services.</returns>
    /// <remarks>
    /// This method ensures that the repositories are registered as scoped services, meaning that a new instance of each repository 
    /// will be created per HTTP request (or per scope) within the dependency injection container.
    /// </remarks>
    public static IServiceCollection AddEnvelopeGeneratorRepositories(this IServiceCollection services, Action<DbContextOptionsBuilder>? dbContextOptions = null)
    {
        if(dbContextOptions is not null)
            services.AddDbContext<EGDbContext>(dbContextOptions);

        services.TryAddScoped<IConfigRepository, ConfigRepository>();
        services.TryAddScoped<IDocumentReceiverElementRepository, DocumentReceiverElementRepository>();
        services.TryAddScoped<IEnvelopeDocumentRepository, EnvelopeDocumentRepository>();
        services.TryAddScoped<IDocumentReceiverElementRepository, DocumentReceiverElementRepository>();
        services.TryAddScoped<IDocumentStatusRepository, DocumentStatusRepository>();
        services.TryAddScoped<IEmailTemplateRepository, EmailTemplateRepository>();
        services.TryAddScoped<IEnvelopeRepository, EnvelopeRepository>();
        services.TryAddScoped<IEnvelopeCertificateRepository, EnvelopeCertificateRepository>();
        services.TryAddScoped<IEnvelopeHistoryRepository, EnvelopeHistoryRepository>();
        services.TryAddScoped<IEnvelopeReceiverRepository, EnvelopeReceiverRepository>();
        services.TryAddScoped<IEnvelopeTypeRepository, EnvelopeTypeRepository>();
        services.TryAddScoped<IReceiverRepository, ReceiverRepository>();
        services.TryAddScoped<IUserReceiverRepository, UserReceiverRepository>();
        services.TryAddScoped<IEnvelopeReceiverReadOnlyRepository, EnvelopeReceiverReadOnlyRepository>();

        services.AddDbRepository<EGDbContext, Config>(context => context.Configs).UseAutoMapper();
        services.AddDbRepository<EGDbContext, DocumentReceiverElement>(context => context.DocumentReceiverElements).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EnvelopeDocument>(context => context.EnvelopeDocument).UseAutoMapper();
        services.AddDbRepository<EGDbContext, DocumentStatus>(context => context.DocumentStatus).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EmailTemplate>(context => context.EmailTemplate).UseAutoMapper();
        services.AddDbRepository<EGDbContext, Envelope>(context => context.Envelopes).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EnvelopeCertificate>(context => context.EnvelopeCertificates).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EnvelopeHistory>(context => context.EnvelopeHistories).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EnvelopeReceiver>(context => context.EnvelopeReceivers).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EnvelopeType>(context => context.EnvelopeTypes).UseAutoMapper();
        services.AddDbRepository<EGDbContext, Receiver>(context => context.Receivers).UseAutoMapper();
        services.AddDbRepository<EGDbContext, UserReceiver>(context => context.UserReceivers).UseAutoMapper();
        services.AddDbRepository<EGDbContext, EnvelopeReceiverReadOnly>(context => context.EnvelopeReceiverReadOnlys).UseAutoMapper();

        services.AddSQLExecutor<Envelope>();
        services.AddSQLExecutor<Receiver>();
        services.AddSQLExecutor<EnvelopeDocument>();
        services.AddSQLExecutor<DocumentReceiverElement>();
        services.AddSQLExecutor<DocumentStatus>();

        return services;
    }

    public static IServiceCollection AddSQLExecutor<T>(this IServiceCollection services) where T : class
    {
        services.AddScoped<ISQLExecutor<T>, SQLExecutor<T>>();

        var interfaceType = typeof(ISQL<>);
        var targetGenericType = interfaceType.MakeGenericType(typeof(T));

        var implementations = AppDomain.CurrentDomain.GetAssemblies()
            .SelectMany(a =>
            {
                try { return a.GetTypes(); }
                catch { return Array.Empty<Type>(); }
            })
            .Where(t =>
                t is { IsClass: true, IsAbstract: false } &&
                t.GetInterfaces().Any(i =>
                    i.IsGenericType &&
                    i.GetGenericTypeDefinition() == interfaceType &&
                    i.GenericTypeArguments[0] == typeof(T)
                )
            );

        foreach (var impl in implementations)
        {
            services.AddSingleton(impl);
        }

        return services;
    }
}