using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using EnvelopeGenerator.Application;
using EnvelopeGenerator.Application.Common.Interfaces.Services;
using EnvelopeGenerator.Application.Services;
using EnvelopeGenerator.Infrastructure;

namespace EnvelopeGenerator.DependencyInjection;

/// <summary>
/// Extension methods for registering EnvelopeGenerator services into an <see cref="IServiceCollection"/>.
/// Use <see cref="AddEnvelopeGenerator"/> as the single entry-point for projects that need both the
/// application layer (MediatR, AutoMapper, CRUD services, configuration sections) and the infrastructure
/// layer (repositories, DbContext, SQL executors).
/// For projects that do not need a database (e.g. lightweight API gateways or unit-test hosts), use
/// <see cref="AddEnvelopeGeneratorCore"/> to register only the application layer.
/// </summary>
public static class DependencyInjection
{
    /// <summary>
    /// Registers the full EnvelopeGenerator stack – application <em>and</em> infrastructure services – into
    /// the provided <see cref="IServiceCollection"/>.
    /// <para>
    /// Internally this calls <c>AddEnvelopeGeneratorServices</c> (application layer) and
    /// <c>AddEnvelopeGeneratorInfrastructureServices</c> (infrastructure layer).
    /// A <see cref="Microsoft.EntityFrameworkCore.DbContext"/> and / or <c>DbTriggerParams</c> must be
    /// configured through <paramref name="infrastructureOptions"/>; without it no database connection will
    /// be established at runtime.
    /// </para>
    /// </summary>
    /// <param name="services">Service collection to register services into.</param>
    /// <param name="configuration">
    ///     Application configuration. Used to bind <c>DispatcherParams</c>, <c>MailParams</c>,
    ///     <c>AuthenticatorParams</c>, <c>TotpSmsParams</c>, <c>GtxMessagingParams</c> and other
    ///     application-level option sections.
    /// </param>
    /// <param name="infrastructureOptions">
    ///     Optional callback to configure the infrastructure layer registration.
    ///     Typical usage:
    ///     <code>
    ///     services.AddEnvelopeGenerator(config, opt =>
    ///     {
    ///         opt.AddDbContext(o => o.UseSqlServer(connectionString));
    ///         opt.AddDbTriggerParams(config);
    ///     });
    ///     </code>
    /// </param>
    /// <returns>The updated <see cref="IServiceCollection"/>.</returns>
#pragma warning disable CS0618 // AddEnvelopeGeneratorServices / AddEnvelopeGeneratorInfrastructureServices are intentionally wrapped here
    public static IServiceCollection AddEnvelopeGenerator(
        this IServiceCollection services,
        IConfiguration configuration,
        Action<EnvelopeGenerator.Infrastructure.DependencyInjection.Config>? infrastructureOptions = null)
    {
        // Application layer: CRUD services, MediatR, AutoMapper, configuration sections.
        services.AddEnvelopeGeneratorServices(configuration);

        // Infrastructure layer: repositories, DbContext, Dapper type maps, SQL executors.
        services.AddEnvelopeGeneratorInfrastructureServices(opt =>
        {
            infrastructureOptions?.Invoke(opt);
        });

        return services;
    }
#pragma warning restore CS0618

    /// <summary>
    /// Registers only the <em>application</em> layer services (MediatR handlers, AutoMapper profiles,
    /// CRUD services, configuration sections) without any infrastructure / database dependencies.
    /// <para>
    /// Useful for projects that already manage their own DbContext or do not require direct database
    /// access, such as lightweight API gateways, console tools or unit/integration test hosts that
    /// use an in-memory database configured elsewhere.
    /// </para>
    /// </summary>
    /// <param name="services">Service collection to register services into.</param>
    /// <param name="configuration">Application configuration used to bind application-level option sections.</param>
    /// <returns>The updated <see cref="IServiceCollection"/>.</returns>
#pragma warning disable CS0618
    public static IServiceCollection AddEnvelopeGeneratorCore(
        this IServiceCollection services,
        IConfiguration configuration)
    {
        services.AddEnvelopeGeneratorServices(configuration);
        return services;
    }
#pragma warning restore CS0618

    /// <summary>
    /// Registers <see cref="EnvelopeMailService"/> as the <see cref="IEnvelopeMailService"/> scoped
    /// implementation.
    /// <para>
    /// Call this in addition to <see cref="AddEnvelopeGenerator"/> when the consuming project needs to
    /// send envelope e-mails directly (e.g. a Worker Service or the Web project). Projects that rely
    /// purely on MediatR commands to trigger mail delivery do not need to call this.
    /// </para>
    /// </summary>
    /// <param name="services">Service collection to register services into.</param>
    /// <returns>The updated <see cref="IServiceCollection"/>.</returns>
#pragma warning disable CS0618
    public static IServiceCollection AddEnvelopeMailService(this IServiceCollection services)
    {
        services.AddScoped<IEnvelopeMailService, EnvelopeMailService>();
        return services;
    }
#pragma warning restore CS0618
}