using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

namespace StellaOps.Provcache;

/// <summary>
/// Extension methods for registering Provcache services.
/// </summary>
public static class ProvcacheServiceCollectionExtensions
{
    /// <summary>
    /// Adds Provcache services to the service collection.
    /// </summary>
    /// <param name="services">The service collection.</param>
    /// <param name="configuration">The configuration section.</param>
    /// <returns>The service collection for chaining.</returns>
    public static IServiceCollection AddProvcache(
        this IServiceCollection services,
        IConfiguration configuration)
    {
        ArgumentNullException.ThrowIfNull(services);
        ArgumentNullException.ThrowIfNull(configuration);

        // Register options
        services.Configure<ProvcacheOptions>(configuration.GetSection(ProvcacheOptions.SectionName));

        // Register core services
        services.AddSingleton<IProvcacheService, ProvcacheService>();

        // Register write-behind queue as hosted service
        services.AddSingleton<WriteBehindQueue>();
        services.AddSingleton<IWriteBehindQueue>(sp => sp.GetRequiredService<WriteBehindQueue>());
        services.AddHostedService(sp => sp.GetRequiredService<WriteBehindQueue>());

        return services;
    }

    /// <summary>
    /// Adds Provcache services with custom options.
    /// </summary>
    /// <param name="services">The service collection.</param>
    /// <param name="configure">Action to configure options.</param>
    /// <returns>The service collection for chaining.</returns>
    public static IServiceCollection AddProvcache(
        this IServiceCollection services,
        Action<ProvcacheOptions> configure)
    {
        ArgumentNullException.ThrowIfNull(services);
        ArgumentNullException.ThrowIfNull(configure);

        // Register options
        services.Configure(configure);

        // Register core services
        services.AddSingleton<IProvcacheService, ProvcacheService>();

        // Register write-behind queue as hosted service
        services.AddSingleton<WriteBehindQueue>();
        services.AddSingleton<IWriteBehindQueue>(sp => sp.GetRequiredService<WriteBehindQueue>());
        services.AddHostedService(sp => sp.GetRequiredService<WriteBehindQueue>());

        return services;
    }

    /// <summary>
    /// Adds the Valkey-backed cache store implementation.
    /// </summary>
    /// <param name="services">The service collection.</param>
    /// <returns>The service collection for chaining.</returns>
    public static IServiceCollection AddProvcacheValkeyStore(this IServiceCollection services)
    {
        ArgumentNullException.ThrowIfNull(services);

        // Note: Actual Valkey store implementation would be registered here
        // services.AddSingleton<IProvcacheStore, ValkeyProvcacheStore>();

        return services;
    }

    /// <summary>
    /// Adds the Postgres repository implementation.
    /// </summary>
    /// <param name="services">The service collection.</param>
    /// <returns>The service collection for chaining.</returns>
    public static IServiceCollection AddProvcachePostgresRepository(this IServiceCollection services)
    {
        ArgumentNullException.ThrowIfNull(services);

        // Note: Actual Postgres repository implementation would be registered here
        // services.AddSingleton<IProvcacheRepository, PostgresProvcacheRepository>();

        return services;
    }
}