using Microsoft.Extensions.DependencyInjection;
using System;
#if NETFRAMEWORK
using System.Net.Http;
#endif

namespace ReC.Client
{
    /// <summary>
    /// Provides extension methods for setting up the ReC client in an <see cref="IServiceCollection"/>.
    /// </summary>
    public static class DependencyInjection
    {
        /// <summary>
        /// Adds and configures the <see cref="HttpClient"/> for the <see cref="ReCClient"/> to the specified <see cref="IServiceCollection"/>
        /// </summary>
        /// <param name="services">The <see cref="IServiceCollection"/> to add the services to.</param>
        /// <param name="apiUri">The base URI of the ReC API.</param>
        /// <param name="configureOptions">An optional action to configure <see cref="ReCClientOptions"/>. When omitted, defaults are used.</param>
        /// <returns>An <see cref="IHttpClientBuilder"/> that can be used to configure the client.</returns>
#if NETFRAMEWORK
        public static IHttpClientBuilder AddRecClient(this IServiceCollection services, string apiUri, Action<ReCClientOptions> configureOptions = null)
#else
        public static IHttpClientBuilder AddRecClient(this IServiceCollection services, string apiUri, Action<ReCClientOptions>? configureOptions = null)
#endif
        {
            AddRecClientOptions(services, configureOptions);
            services.AddScoped<ReCClient>();
            return services.AddHttpClient(ReCClient.ClientName, client =>
            {
                client.BaseAddress = new Uri(apiUri);
            });
        }

        /// <summary>
        /// Adds and configures the <see cref="HttpClient"/> for the <see cref="ReCClient"/> to the specified <see cref="IServiceCollection"/>
        /// </summary>
        /// <param name="services">The <see cref="IServiceCollection"/> to add the services to.</param>
        /// <param name="configureClient">An action to configure the <see cref="HttpClient"/>.</param>
        /// <param name="configureOptions">An optional action to configure <see cref="ReCClientOptions"/>. When omitted, defaults are used.</param>
        /// <returns>An <see cref="IHttpClientBuilder"/> that can be used to configure the client.</returns>
#if NETFRAMEWORK
        public static IHttpClientBuilder AddRecClient(this IServiceCollection services, Action<HttpClient> configureClient, Action<ReCClientOptions> configureOptions = null)
#else
        public static IHttpClientBuilder AddRecClient(this IServiceCollection services, Action<HttpClient> configureClient, Action<ReCClientOptions>? configureOptions = null)
#endif
        {
            AddRecClientOptions(services, configureOptions);
            services.AddScoped<ReCClient>();
            return services.AddHttpClient(ReCClient.ClientName, configureClient);
        }

#if NETFRAMEWORK
        private static void AddRecClientOptions(IServiceCollection services, Action<ReCClientOptions> configureOptions)
#else
        private static void AddRecClientOptions(IServiceCollection services, Action<ReCClientOptions>? configureOptions)
#endif
        {
            // Ensure default options are always registered even when the caller does not configure anything.
            var builder = services.AddOptions<ReCClientOptions>();
            if (configureOptions != null)
                builder.Configure(configureOptions);
        }
    }
}